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  1. #31
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    Quote Originally Posted by Stustoys View Post
    Damn things happen fast in your shed. Looking good.

    You could..... you know.... fix the direction of rotation issue. I wont tell
    I could, but not in the way you're probably thinking... Oil pump no workies if you run the motor backwards! However the round piece that the clutch rod goes into at the front is basically just a thick piece of tube with a helical slot milled in it, which then pushes the linkage through to the back of the headstock one way or the other. I could make a new one with the helical slot in the opposite direction, and that would work. But I couldn't be bothered, I'll just get used to it.

    Certainly hasn't FELT like it's been happening fast, I can tell you... lol.

  2. #32
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    That is a very cool 3 jaw. I want one now, must have cost a fortune as there is so much more work in it.

    Sent from my SM-G973F using Tapatalk

  3. #33
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    Quote Originally Posted by caskwarrior View Post
    That is a very cool 3 jaw. I want one now, must have cost a fortune as there is so much more work in it.

    Sent from my SM-G973F using Tapatalk
    I suspect the body may be forged or semi-steel as well, rather than straight cast. It rings like a bell when you tap it with a small hammer, rather than going donk... Although when it's back together that effect may abate somewhat. Given it's probably not much newer than the lathe, as you say it must have been a truly eye watering price 60 odd years ago. I don't think I'm game to run the Mario Pinto at 1800rpm (definitely not with anything sizeable), but if I needed to run a 3 jaw at that speed for some reason, I think I'd be prepared to chance it with this one (none of the chucks have speed ratings on them).

    It'd be nice if I had the internal jaws for it as well, I only have the 2 piece and the external jaws for that one - then again, maybe that's all it ever came with. New non-mangled jaw tops for that one are on the future project list, along with more tool holders, jaw tops for the other one, etc, etc...

  4. #34
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    Decided I wanted to play with it today, instead of just cleaning tooling etc. For some reason I don't have a chuck key that fits the camlocks on the actual spindle, so that seemed like a good little project. Remembering that I had some interest in the taper turning attachment, I went all out for you lot and made it tapered JUST so you could see the taper turning attachment set up.

    Not in the slightest bit because the chuck key for the 9" chuck is tapered and I liked the look and figured I'd kind of match it, nor at all that I just wanted to try the taper turning attachment out - no, purely for your edification.

    IMG_1542_1400x1050.jpg

    So that's what it looks like in action, setup for just under a 1 degree taper (was about what worked out with the dimensions I ended up with). I really don't think that the 'support' at the headstock end is needed at all. That particular support is a welded unit someone has knocked up, and I suspect the threaded bar going into it was also made up because someone 'thought' it needed it. It probably had the hole tapped on the headstock side in case of wanting to turn a taper right up at the tailstock end, in order to allow the bar to stick out towards the headstock, which was most likely the clue to a previous genius that THINGS ARE MISSING™. Or maybe it didn't have the hole, and they tapped one in because 'all the other taper turning attachments I've seen need TWO supports!' - I haven't actually checked if they're the same thread or not (it's guaranteed to be imperial thread if it's a modification). Both the SAG180 and SAG14 manuals I have only show one rod, but the taper turning attachments themselves are a bit different (I suspect mine is a very early version, possibly even one of the first they offered). Nonetheless, the size of the casting it all rides in, and the basic layout are quite similar, so I strongly suspect it was originally delivered with just the bar that's on the tailstock end, and that cast support with the lever (which engages in a slot in the bar).

    Notice the big blue chips floating around - I started with 1" bar, and wanted 14.5mm at the square end. Bit over 10mm off the diameter? Eh, 5mm DOC for a roughing pass sounds about right! It's going to take a fair while before I get bored of that...

    Also swung the taper setting part around to a more exaggerated angle before pulling the supports back off the machine, just in case anyone was struggling to see quite what was going on:

    IMG_1543_1400x1050.jpg

    The lever hanging out under the 'snout' is what locks out the taper turning attachment, effectively it clamps the sliding bush that holds the end of the cross slide screw to the snout. Going back to one of the posts on the first page will show you the sliding bush that rides inside that snout. Forgetting to unlock this lever before hitting the powerfeed with a taper set and the outboard supports installed would result in rather horrible noises, I'd imagine. Hopefully if I ever DO manage that particular feat of stupidity, the supports will slide along the bed rather than something else yielding.

    Fortunately not today though, todays stupidity was limited to attempting to do 1mm DOC passes by dialing in '40' on the cross slide. Was rather confused for a moment after the second pass, when only 0.8mm had come off the radius... Then realised I'd somehow subconsciously decided that '40' was 40 thou, thus 1mm - which it would have been originally, but I needed to dial in '50' to get 1mm. I knew that was going to do my head in. What's worse is I did the same thing again later...

    On a minor detour now, a little rant if you will about the mysterious persons past who have 'fixed' things without spending even the briefest moment to think about how it actually works - which may also explain why I'm being rather a smartass about the taper attachment bits. Todays example:

    IMG_1536_1400x1050.jpg

    Oh noes, the holder won't go low enough to get the 26mm parting blade on centre! Let's just hack off the bottom of the holder with the bench grinder... Now, I don't know about you guys, but to me that pair of unused 6mm tapped holes offset above centre line in the parting tool just scream "bolt a block to me". All that had to be done, was to drill a pair of holes on the centreline of a piece of 25mm square bar, bolt it to the parting tool, and voila - the bottom of the 32mm body would be hanging down below the bottom of the 'shelf' in the holder. Probably would have taken exactly the same amount of time as hacking away at the hardened holder on the grinder... This is not the only holder that's encountered a grinder either, there is another that's had a very light tickle - even though the tool in it has had the bottom milled off it. Don't know why they didn't just take another 1mm off the bottom of the tool. The keen eye will also note that the height adjustment stud for this particular holder in the photo has been welded in - I can only assume that the thread is stripped, and being a hardened holder unviable to drill and retap (I'm certainly not going to cut the weld off to confirm that). Fair enough I guess, but surely you'd take the frigging adjustment bobbin off before you did it - or at least clean the weld spatter off the bottom of it once you're done. Guess I know where the gouges in the locking cam on the toolpost came from....

    Other notable examples of brain not engaged that spring to mind - way back at the beginning of this thread somewhere I mentioned that the tailstock quill lock didn't work that well, and had a couple of random washers added to it.

    tailstock lock.jpg

    How it's SUPPOSED to work, is that part 1828 is a bronze bush, sliding fit in the bore with a circular cutout in it to match the radius of the tailstock quill, and it's pinned to the stud 1880. Part number 1829 is basically an identical bronze bush, except that it is free to float on the stud. Part 1830 is a steel part, sliding fit in the bore, but with internal threads to match the stud, and the handle screws into the side of it. Note that it has a shoulder on it - this does NOT ride against the tailstock body, there is about a 3mm gap when it's assembled. The idea is that when you use the locking handle, the steel part does up on the stud, and squeezes both 1828 and 1829 together to clamp the tailstock quill between them. Problem with mine (sans washers) is that the knob on the handle fouled the body before it locked fully. So someone very smart has jammed a couple of big fat washers between the shoulder on part 1830 and the tailstock body, and now the lock lever stops in the right place. The lock doesn't real good, of course, because when you do it up it's now only pulling on 1828 whilst pushing on the tailstock body - part 1829 might as well be off getting drunk at the bar while 1828 is valiantly trying to use his tiny frame to wedge the quill against the well lubricated 50mm tailstock bore. So, after I ducked from the rebounding washers I lobbed over my shoulder, I put a couple of shims salvaged out of car shocks in between 1829 and 1830. 0.6mm worth of shims got the handle to the right place, and the lock works very well. Of course, being a 1.25mm pitch thread, turning 0.6mm off the back of 1829 would have had the exact same effect, but it would have been a bit of a trial and error process - and of course, this is reversible.

    Another one that had me shaking my head was when I looked at why the change gears seemed to be just rattling around loose on the shafts, despite the retaining bolts being tight, and the washers being in place. Turns out, for some bizarre reason, someone had put smaller washers behind the factory ones - small enough that they fit inside the bore of the gears. So the bolt was just doing up on the washer stack, but the gears weren't actually being clamped against the shoulder on the shaft... Again, washers went over the shoulder, flattened the factory washers out (they were cupped enough to not quite clamp on the gears), and now the gears are actually held in place against the shoulder by the washer.

    I really can't figure out the thought process that went on here, it almost seems like when they took off the bolt and factory washer, they saw that the shaft was below flush in the gear, and went "Bloody wogs, can't get anything right, better fill that up..." Probably a more likely scenario though is that the when the factory washers got cupped out, someone put the extra washers on the front, to help pull the outer edges of the factory washers down against the gear (instead of taking the 10 seconds it took for me to belt them flat again with a big hammer). Then someone else came along later, changed the gears around for some reason, and forgot where the washers were, and didn't even look at what these obviously not original washers were supposed to be achieving.

    Some others I've already mentioned, like the missing thrust bearing race inside the taper turning snout, and the greased powerfeed rod bearing. The leadscrew however, at the tailstock end, has no seals. Instead, it uses hardened washers with an eccentric groove ground on one face. The washers also have a keyway in them, and the idea is that one goes each side of the support casting, grooves facing the casting. When the leadscrew rotates, the grooves wipe the oil around the mating faces. Except they don't do that very well when the 4mm dowel pins that engage the keyways are left out of the leadscrew sometime in history.

    I really shouldn't complain too much, I guess, as everything has just been a fairly simply fixable problem - no permanently compromised parts, or worn out beyond repair. But by the same token, the fixes have usually been so simple I'm really wondering about the mechanical aptitude of the person who got there before me - I kind of really hope it wasn't someone who was running the machine, and using it to repair other things.... Given the amount of paint over many, many things (including the 'replacement' taper turning support, and the adjustment nuts for the end of the leadscrew), I have to suspect much of it may have been done by ESP machinery many many moons ago - or at least was done before they acquired it and (presumeably) blasted paint all over it for sale.

  5. #35
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    I had a minor brainwave, and measured the thread on the headstock side taper support rod. Measures out at 18.7mm diameter, and matches 10tpi on my thread gauges, which would probably make it 3/4 UNC. Of course, 2.5mm also matched, but checking with a ruler over a longer distance proves it to be 10tpi, which basically cements it being an addition. Pretty much every time I've looked at something on this machine, and thought 'I don't think that's how it originally was', the threads have been imperial. Anything factory is metric threaded (except of course the leadscrew and originally the various slide screws). Still haven't unscrewed the rods and tried swapping them over, but I'd expect that the thread into the taper slide is metric, for the reason I mentioned earlier (turning tapers at the tailstock end).

    This would also make the lever on the tailstock side support make far more sense - after all, why would you go to the effort of having basically a quick release on one support bracket, and then have a fiddly threaded arrangement at the other end? In theory you should be able to leave that single support bracket mounted on the machine in whatever place suits your need, flip the lever up to disengage it from the rod, and use the machine as per normal, with the rod just sliding freely through the support bracket. The rod has a big chamfer on the end which would probably allow it to self align if you came out of the support on the headstock side, but there is a bit of a shoulder that would probably snag if it ended up on the tailstock side of the support... Dunno.

    Either way I'd say the headstock side support bracket and rod have been made up and added later, either due to being perceived as 'missing', or perhaps attempting to solve some sort of problem (possibly real or imagined) of deflection somewhere during use - which I can't see being a real problem. Time will tell I guess, if next time I use it (whenever that may be) I only put the one support on and find it causes problems.

  6. #36
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    Hi J&H,

    Other notable examples of brain not engaged that spring to mind - way back at the beginning of this thread somewhere I mentioned that the tailstock quill lock didn't work that well, and had a couple of random washers added to it.

    La Principessa Italiana - Graziano SAG 180-tailstock-lock-jpg




    I tend to use split collets quite a lot, I'm a little surprised that they didn't just use a screw threaded into one side, rather than going to the trouble of using a pinned in screw. They have used a threaded handle and could have clamped the screw anywhere from that end.
    Best Regards:
    Baron J.

  7. #37
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    Quote Originally Posted by BaronJ View Post
    Hi J&H,

    I tend to use split collets quite a lot, I'm a little surprised that they didn't just use a screw threaded into one side, rather than going to the trouble of using a pinned in screw. They have used a threaded handle and could have clamped the screw anywhere from that end.
    Not sure why they did it like that, possibly a concern about the threads pulling out of the bronze bush over time or failing when a hamfisted operator really heaves on the locking lever I guess. Or maybe it made it easier at the factory to 'fit' the parts upon assembly in order to get the handle in the right place.

  8. #38
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    Been a bit lazy lately, lots more time thinking about doing things than actually doing anything. Nonetheless, slowly getting a few smaller jobs out of the way, printed a knob for the tailstock handle out of black polycarbonate, sanded and polished it and it's ok. Also turned up the little mushroom shaped pieces to act as the friction locks for the tailstock graduated dial, which amused me somewhat given they were 8mm at the large OD, and 6mm long, hanging out of a 230mm chuck. Few other little bits and pieces moving along slowly in the background.

    I also now have this:

    IMG_1563_1400x1050.jpg

    The parts have been arriving slowly, I've actually already had the Z axis on for a couple of weeks now. I wanted to use a KA200 scale on the cross slide for reasons that will be very apparent shortly, but none of the packages seem to offer that option, so I bought all the bits seperately. Picked up the SDS6-3V on eBay, brand new from someone in QLD, the 1020mm long 1um KA300 scale was on sale from a seller on eBay which came (strangely enough via UPS) out of China, and the 340mm 1um KA200 came from Aliexpress, which was a catalogue size but not a stock size, apparently, so it had to be made first. Which is why it only turned up today. I know there's not a whole lot of point in 1um scales, but it didn't actually end up costing me any more all up than a 5um 2 axis package without the slimmer KA200 scales would have. And I have a spare axis that I can either decide to use at some point, or swap that readout to the mill, and buy a 2 axis readout and another scale to put on the knee of the mill.

    IMG_1557_1400x1050.jpg

    KA300 mounted for the carriage on the convenient machined pads the factory left me - if anyone was previously wondering why on earth I left them unpainted, now you know .

    IMG_1559_1400x1050.jpg

    IMG_1561_1400x1050.jpg

    Think this shows why I wanted the KA200 scale specifically on the cross slide - it fits just perfectly in the space. Cover sits just below flush with the lowest part of the cross slide, so no edge for chips to build up against (for easy cleaning), and the entire assembly sits in the space above the coolant gutter on the carriage, so nicely protected from 'accidents' involving the tailstock. And I've lost an entire 5mm of tailstock movement in the process, which given the quill moves 160mm, I'm really not bothered by that at all. The slight odd staggered mounting pattern for the read head bracket is because I used the existing M6 holes - not a fan of adding holes anywhere to mount things if there are existing ones that can be made to work. Seen too many cars and machines which are more holes than metal from all the different things that have been mounted in a given spot over the years.

    Cable management needs some.... attention... yet, lol, but I'm pretty happy with how the actual mounting of the scales ended up.

    In the process of mounting the readout, I also discovered an unsung advantage to running a VFD. (The part was a spigot to put in the end of the tube for the brackets on the back out the readout to bolt to, once the radius was profiled I milled two flats in and cross drilled a hole. The radius allows clearance for the readout to tilt up and down a bit.)

    IMG_1553_1400x1050.jpg

    IMG_1555_1400x1050.jpg

    The advantage is that when you have a crash, the overcurrent protection trips very fast. Still not sure whether I failed to take the 0.5mm of backlash out of the cross slide on the last pass, whether I caught the corner of the tool at the OD, or whether the load of the 1/2" radius form tool at full engagement was just to much for the part in question (a piece of scrap which had a random hole drilled up the guts from some past endeavour). Either way, I heard the crunch of the part climbing up onto the tool, and the motor was already off before I'd even had time to react. It did maybe half a revolution total with the tool dug in there, no noticeable damage to anything other than the part (even the HSS tool was fine). I think had it been running straight off 3 phase like normal, this would have been a much more exciting crash by the time either I'd reacted, or the fuses had blown. Not exactly going to rely on it to save my ass, but it is nice to know if you have a serious oops that the VFD will likely shut it down fast enough to keep the damage to a minimum.

  9. #39
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    Quote Originally Posted by Jekyll and Hyde View Post
    lots more time thinking about doing things than actually doing anything.
    lol I said pretty much the same thing to someone just the other day.

    Seems I've fallen a little behind.
    Just to be a pedantic prick 1828 is the pin, the bronze bushes are 1829 and 1829/1. But hey even I managed to work out what you meant.

    I wonder if they felt they needed a taper support at the headstock when cutting tapers away from the headstock. Not really seeing it myself but then I have never used one.

    Quote Originally Posted by Jekyll and Hyde View Post
    I know there's not a whole lot of point in 1um scales
    You think they are a waste on a lathe? I have them on my mill.......... because well why not lol

    Its come up great so far. Is the end in sight yet? Got to be close surely.

  10. #40
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    Quote Originally Posted by Stustoys View Post
    lol I said pretty much the same thing to someone just the other day.

    Seems I've fallen a little behind.
    Just to be a pedantic prick 1828 is the pin, the bronze bushes are 1829 and 1829/1. But hey even I managed to work out what you meant.

    I wonder if they felt they needed a taper support at the headstock when cutting tapers away from the headstock. Not really seeing it myself but then I have never used one.


    You think they are a waste on a lathe? I have them on my mill.......... because well why not lol

    Its come up great so far. Is the end in sight yet? Got to be close surely.
    Guilty as charged your honour, I completely screwed up my numbers. Not sure how I managed to mangle that so badly. Have to see if I can fix that, although most people who are going to read it probably already have...

    They may well have felt that they needed a taper support at the headstock for that reason, but it really wouldn't do anything that the one at the tailstock end doesn't. I'm quite certain it's a pointless modification personally, until such time as I turn a taper and find a reason why it isn't....

    On an old manual machine 1um probably isn't really needed for the most part - how many machines can realistically hold to 0.001mm anyway (or even 0.005mm)? Cutting deflection, slight movement in slides, etc - not to mention the issues you well know about actually MEASURING to that tolerance. I have a hard enough time positioning the 5um on the mill to x.000 (instead of x.005 for example), usually involves me using the handwheel like a small hammer to tap the last digit into place, and/or dragging the locks as I approach (because they change the reading too). Not sure why I bother half the time anyway, but that .995 or .005 staring at me just gets to me (even worse when you get .000, make the cut and look up to find its gone .995 again)... So far, it looks like it would be even harder to get the Graziano carriage positioned 'triple 0' even with 5um, as it's got a bit of stick-slip and one rotation of the handwheel is about 19mm of travel. Getting within 0.02mm is about as easy as getting within 0.002mm on the mill, so unless I develop a knack it's going to be pretty pointless!

    In hindsight I probably should have at least broken the sliding surfaces on the carriage up with the scraper to create at least a little bit of oil pocketing...

    There is of course one good argument TO go with 1um on the lathe though, and that's if you run in diameter mode on the cross slide, whereby you effectively halve your resolution. So a 1um scale gives a minimum increment of 0.002mm, but a 5um scale gives a minimum increment of 0.01mm. So if you're targeting 20.50mm on the diameter, and set that on the cross slide, you could actually be anywhere from 20.4951 to 20.5049 (if I've done my maths right). Flip side of that is, how many of us can successfully cut within 0.01mm of a target diameter regularly on our machines? I've certainly missed it slightly more times than I've hit it, although time will tell I guess whether the Graziano and the DRO combined will allow me to better that (and I may just be crap!).

    As you pointed out though, given the minimal cost difference with the Sino or other Chinese scales most of us run, why NOT go with 1um. Having the greater accuracy there certainly gives us the best possible chance of hitting a target figure, if we can align the rest of the planets. And hence why I have 1um (beside the fact that I actually ended up getting the 1ums slightly cheaper than 5um normally are!)

    I don't know where the end is....

    There are a lot of little jobs of varying importance that I want or would like to do. The missus has been working on digitally reconstructing the threading data plate which I put in the scanner. Part of the feeds section is obliterated, but the bigger issue is that it's been battered around and the metal is quite stretched, so there is no way it's ever going to sit flat again. I want to get a replacement done, probably laser marked and then laser cut (lots of holes in it), but possibly screen printed. I definitely want that back on the machine for the convenience.

    The VFD needs a home - currently it just sits on it's back on the floor. My intention is to mount it under the motor with a little roof over it, but needs some thought applied as to how to actually MOUNT it rather than it just sitting on the ground inside the cabinet (not a viable option due to the fan underneath). This ties in to one of my other 'wants' which is to build a pair of pedestals that go under the headstock and tailstock to lift it up 6 inches or so (have some hefty channel kicking around for that job). Thinking I'll build the mount for the VFD on that somehow. Also want to wire the original start switch into the VFD, along with the 'reproduction' stop switch I 3d printed to match it.

    Then there is the whole 0.8mm too narrow gib for the compound to think about, which brings along the question of should I scrape the compound before making a replacement, which then brings the question should I scrape the cross slide....

    Also want at some stage to replace the solid cross slide nut someone made when they metric converted it. The original design was a 3 piece arrangement (split vertically) with a wedge section in the middle, that pushed the rear outer part towards the back of the machine, but I'll make the later SAG14 style, which was split horizontally, and had 4 springs and screws to pull the lower half up against the upper half, and also had an oiler feeding into the middle (where the adjustment screw was on the SAG180 design). The SAG14 design is actually particularly clever, as if I understand it correctly it can expand a bit when it travels over an unworn portion of the screw.

    One of the pistons for the toolpost is cracked, so I'd like to make a new one at some stage, although at this point I just put it on the tailstock side and it's not a problem. DEFINITELY want to make a bunch more toolholders though, I had 15 for the AL335, and having only 6 is just... painful, lol. At $90 each for Chinese ones, ain't gunna be buying them.

    And once I've sorted all that, and anything else I've forgotten at the moment (I'm sure there is something), I need to figure out how I'm going to store all the related crap. Current scheme in mind is to build a cabinet that fits under the chip tray with drawers etc. Should be a decent bit of room if I build the riser platforms like I mentioned, but planning out how to best utilise that space will be the trick, as it's not a 'square' space due to the shape of the chip tray.

    Of course, some or all of the above may never happen, since it's currently perfectly functional...

  11. #41
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    One of the things I've been wanting for the Graziano is a collet chuck. I had one for the AL335, an ER40 D1-4, but of course that doesn't fit the D1-5 Graziano, so it went with the AL335. I kept the collets though, as the mate who bought it has plenty of ER collets for his other gear.

    I could have bought one, but aside from being a tightass and not wanting to spend $100+ on a 125mm ER40 plate, they're all pretty low profile. Which would be fine, except that I have a bit of wear on the ways, and getting that close to the spindle the carriage gets a bit tight, so I was concerned that I'd end up with tapering parts from running up on the unworn section. Probably wouldn't have actually been enough to cause much of a problem, but I decided I wanted the collet face to be in line with where the tips of the jaws on the 3 jaw would be. I also wanted to make it set true, because... well, because. Partly that the 4 jaw only grabs down to 16mm, which I could solve by holding a collet block in the 4 jaw - but it's heavy to put on, and I wouldn't be able to run high rpm.

    So anyway, I had this lot:

    IMG_1564_1400x1050.jpg

    A D1-5 backplate that came with the Graziano, peppered with holes to the extent I'd struggle to find a clear spot to mount any other chuck of any decent size to it anyway, and a... part. I'm interested to see if one of the regular viewers of this thread manages to correctly identify it, so it's provenance will remain a mystery for the short term....

    Step one was to machine some 9mm OD plugs with an M6 thread inside to press into the holes around the base for the set true, as tapping them out proved to be no go. Combination of a bit of induction hardening and a blunt tap, I think. Then into the 4 jaw, dialed in true on both the face and the OD, and see if I could actually chew through it at all.

    IMG_1566_1400x1050.jpg

    Sure enough, got that all faced off (heavy interrupted cut, not just from the bolt holes at the start!), and bored the centre out to 75mm. That out of the way, I checked the fit of the backplate on the spindle, to make sure it pulled up properly, and indeed it required a light tap with a dead blow to release it, so moved on.

    Next step was to lop off a bit of some 76mm hydraulic ram I had, and turn it down to a press fit in the backplate which was 56.5mm. A painful process getting through the 3.5mm thick hardened outer, but I got there. I'm going to utilise my right to backpedal on DRO accuracy at this point, too. The last cut on the press fit diameter was at 56.506 on the DRO, and near as I can tell with my 0.01mm micrometer that's almost exactly what I got. Pressed it into the backplate, turned the OD to 74mm and faced it to length (after bulldozing off the hardened outer with a CBN insert). I'd left myself way too much material, so had 16mm to face off, which gave me a chance to experiment with a few tools. CNMG didn't really work that well for facing this material, but the KNUX with the massive 1.2mm nose radius and deep chipbreaker groove absolutely ripped. I got up to 3mm cuts off the face before I ran out of material to remove, and it just did it easy.

    Conversely on the OD the KNUX wouldn't break a chip unless at a very slow feed, trying to increase it just made death ribbons. The CNMG worked far better here. I figure it's something to do with how this material flowed over the chip breaker.
    Then drilled and bored the center out to 34mm clearance size, and pulled all but 2 opposing camlock pins out of the back plate, and threw it in the vise on the mill holding on the two remaining pins. This gave me easy indexing to align the 4 holes for the soon to be collet chuck, without breaking through into the camlock pins. Then refit the backplate on the lathe.

    IMG_1576_1400x1050.JPG

    You can just make out the shiny ring of hardened material at the outside edge of the 'plug' in the backplate, which works out well having that hardened surface for the set true screws to push on. From here, I mounted the part that would become the chuck, after lopping the end to rough length with the angle grinder, and started dialing it in with the screws. At which point one of the threaded plugs started to get pushed out from the load of the screw, which I'd kind of expected to happen even though I'd used green Loctite retaining compound. Fixed that by running the tig around the outside of them, which ended up costing me an M6 tap clearing the threads and a couple of corners of inserts when I machined them flush, as apparently welding this material the chuck is made of makes it incredibly hard.

    I then skimmed the end to suit the 50x1.5 thread of ER40 collet nuts, and machined the splines back. Much to my surprise, they turned off stupidly easy, with chips that almost looked like cast iron. I'd expected them to be hardened, but no. Still don't know what this thing was made off, it was machined all over so I figured it to be some decent grade of high tensile steel, but I'm suspecting it was actually cast steel (the hardness of the weld zone kind of hints at that too I think). Needless to say, the HSS Komet threading tool had no issues, and I got a very nice fitting thread (collet nut raided from my ER40 R8 chuck from the mill that I rarely use).

    Finally, I used the DRO to set up the taper turning attachment to 8 degrees, and started cutting the ER40 taper. That proved to be unviable, thanks to the 0.5mm backlash in the cross slide mostly (I think). If it was an OD, it would have worked fine turning towards the headstock, as the cross slide would always be pulled by the taper attachment. (if the taper had been small end towards tailstock, would have had to cut left to right on the OD to achieve that) But with the tapered bore, it constantly wanted to float and created a stepped bore, even with me leaning against the tool post as hard as I could. Running from inside out would probably have worked better, but I couldn't see anything inside the bore by the time I had the 25mm bar in there. Decided to abort that, and used the compound instead, which gave a much better result.

    IMG_1578_1400x1050.JPG

    IMG_1580_1400x1050.jpg

    As you can see I also decided to remove the extra bit of faceplate, the tapered bit was what I had to do to get rid of the 3 holes on the smallest PCD, and just happens to be stylish. OCD is a bugger.

    Camera makes the finish on the cast look horrible, as it's kind of porous...

    Checking the runout on various things held in collets (even on the low end of the collet clamping range) consistently gives around 0.005mm runout (or slightly less, but I'm reading between lines again!) close up against the collet nut. Given the M&G collets only claim 0.008mm runout, and Hardinge 'special accuracy' 5C collets claim 0.005mm, I think I'm probably happy enough with that...

    I haven't removed it from the spindle yet, but given the backplate is a good fit, I'm hopeful if I mark its position before removing it that it will still hold that accuracy when refitted. If not, there's always the option of adjusting the set true screws...

  12. #42
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    Quote Originally Posted by Jekyll and Hyde View Post
    Finally, I used the DRO to set up the taper turning attachment to 8 degrees, and started cutting the ER40 taper. That proved to be unviable, thanks to the 0.5mm backlash in the cross slide mostly (I think). If it was an OD, it would have worked fine turning towards the headstock, as the cross slide would always be pulled by the taper attachment.

    I don't have a taper attachment yet (or a Grazi'), but have been thinking about this.

    1. Why would "pulling" the cross slide (back toward turning centre line)
    be any better than the slide pushing out for the cut, toward the operator?
    I mean, backlash is backlash. You are either pushing on one side of the "slop" or the other?


    2. If for some reason I don't understand, cutting the front ID was inaccurate,
    what about reversing the spindle, flipping the taper attachment rod, and cutting the rear ID?

    (away from the chuck would be pulling cross slide back, away from centre line)

  13. #43
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    Quote Originally Posted by nigelpearson View Post
    I don't have a taper attachment yet (or a Grazi'), but have been thinking about this.

    1. Why would "pulling" the cross slide (back toward turning centre line)
    be any better than the slide pushing out for the cut, toward the operator?
    I mean, backlash is backlash. You are either pushing on one side of the "slop" or the other?


    2. If for some reason I don't understand, cutting the front ID was inaccurate,
    what about reversing the spindle, flipping the taper attachment rod, and cutting the rear ID?

    (away from the chuck would be pulling cross slide back, away from centre line)
    This is probably going to be as clear as mud, but I'll give it a go...

    Cutting the ID on the front side, with the narrow end pointing towards the change gears, the taper attachment is pulling the tool post to the rear of the lathe. (via the screw and nut). So as you approach the bore, the backlash is taken out slowly (or more accurately, it's gathered on the rear side of the toolpost).

    Now when you hit the bore, the cutting forces want to push the tool away. And since all the backlash of the screw is gathered on the back side of the toolpost, the tool is free to move away by UP TO the amount of backlash you have. Then the next bit of carriage travel, the taper attachment is just pulling the slack back out of the screw, instead of actually pulling the toolpost. The taper attachment is pulling on the screw (in tension), but the toolpost is pushing on the screw (in compression) from the cutting forces - effectively, the tool is basically free to float (in my case by 0.5mm). It could push away, it could dig in...

    If you think about it in terms of a regular cut (ignoring the taper attachment for a minute) it's exactly the same (just mirrored) as if you attempt to set the diameter for a cut on the backside of an ID bore, by winding the crosslide towards the front of the machine. Or do the same to cut an OD on the front side. The backlash is on the wrong side, as soon as the tool hits it'll want to jump away from the workpiece and will take a shallower cut than intended (and inconsistently so)...

    If you cut the OD with the same setup, (smaller diameter towards change gears), the taper attachment pulls on the screw, all the backlash ends up on the rear of the toolpost. The cutting forces are trying to push the tool to the front of the machine, which translates to the toolpost pulling on the screw against the taper attachment. Both the taper attachment and the cutting forces at the tool post have the screw in tension.

    As for point 2:

    Quote Originally Posted by Jekyll and Hyde View Post
    Running from inside out would probably have worked better, but I couldn't see anything inside the bore by the time I had the 25mm bar in there.
    Running inside out (carriage to tailstock) on exactly the same setup worked somewhat better, as cutting load and taper attachment both put the screw in compression, but I just couldn't see what the hell I was doing, how deep I was, etc, so I was struggling to pick up at the right point, and set the depth of cut with any accuracy. Only having a small handful of toolholders, I had no other boring bars installed in a holder, and at this point definitely didn't want to break the setup down so I could get a smaller one installed on centre, and then find that it chattered anyway. Also wasn't super confident it would completely alleviate the problem, and didn't want to overshoot the diameter finding out.

    Could also have flipped the boring bar upside down, or used an opposite handed boring bar, set the taper attachment to 8 degrees the other way and cut the backside of the ID instead, but would still have to cut towards tailstock (going in would have taper attach working in compression, cutting force in tension). See above...

    Whether that is the entire cause of my issues, dunno. More experimentation required at a later date when I have time, but certainly some reading on Practical Machinist and some critical thinking suggests that it will be a big part of it.

  14. #44
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    It has been some time since I've put anything in this thread... This time last year, I made a 350km move in the middle of Covid lockdowns to a 5 acre property (with 135sqm shed). Due to the way settlements worked out (and an exorbitant 'lease' fee being asked by the new owners of my old place), the move was actually done in two stages. Fortunately, just 1 month before OUR settlement, my folks had moved 180km in the opposite direction, and their new place is 10km away from here. So stage one was 3 trips over two weeks in the little rental moving trucks, and filling up Dads shed (and the spare room!) with the contents of my house and shed, as well as a trip with a car trailer and a trip with a box trailer. In the mix there was also loading the mill and lathe onto Shane from Total Crane Trucks truck, to go into storage at his place in Pakenham for 3 weeks, and a LOT of throwing things in a skip (yes, I've already wanted numerous bits of smaller scrap I threw in there). Then a 3 week 'holiday' at the folks new place, and repeat the process again, minus the 700km round trip part.

    As you can imagine, the year since has been full of things mostly unrelated to metalworking, and much more to do with helping the folks sort out various things around their 7 acres, in between sorting out a whole mess of jobs around here. I'm finally managing to get a bit of balance back now though, and as some of you might have seen in another thread I've been scooting things around my shed the last couple of days, figuring out layouts. Think I've now cracked it, and have worked out how to lay it out and still have room for a shaper and a surface grinder in the corner I've painted myself into.

    The major holdup on this particular front for the last year has been that I wanted to build the pedestals for the Graziano to make it easy to position it wherever I want, without having to stuff around with the bits of SHS for the skates etc - and it has literally taken me the last year to get through these. This picture was in the other thread, but here it is again:

    1662799374296_1400x1050.jpg

    The sides of the pedestals have been drilled and tapped to allow me to simply bolt my homemade skates I built years ago straight onto them. Thus, lift the lathe with the jacking screws, bolt on skates, undo jack screws, and away we go. Obviously, this photo was a test toast before completion.

    1662799374277_1400x1050.jpg

    So here they are, painted up to match the lathe. The construction is a mix of some heavy C channel I've had lying around for years that was never quite long enough to do whatever I wanted, infilled with bits of 6mm plate and some thickwalled pipe sections. The headstock pedestal is 42kg, and the tailstock one is 31kg.

    The other thing that made this drag on a bit, is that I really wanted somewhere to put the VFD, and not in sight. But there wasn't really any space...

    1662799374261_788x1050.jpg

    After much deliberation, I did end up making a mounting arrangement set down in the headstock pedestal. There is a little aluminium roof over the top of the VFD to stop oil dripping on it (yes, there are still oil leaks in there!), and the cables are tied to little loops on the side to make sure they go down, then back up into the VFD, meaning any oil that runs down a cable just drips off the bottom of the loop, and doesn't end up in the VFD. The start/stop switches on the front of the machine are also now operational.

    Aside from this, just before the move I bought a couple of lengths of 1045 steel to make toolholders. I completed the first one before I moved, and made sure my drawing was correct, and then all the blanks I'd cut got boxed up, moved, and sat on the shelf for a few months. I did manage to get them out, and currently I have 7 half machined toolholders on the bench, waiting for me to find time to get back to them. Basically they just need the big Vs machined in them, and the holes drilled and tapped, the rest is machined out. Well, except for the one that is going to directly take an insert parting blade, but that's a different story....

  15. #45
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    Meet the family...

    la famiglia.jpg

    8 brand new toolholders, one not quite so brand new (the one on the far left was the first I made over a year ago), and the proud grandparent bringing up the rear (an original Rapid Type B holder).

    The keen eye will notice one of these things is not like the others... It's also somewhat been the bane of my existence. I actually originally had one of the other holders left a bit oversize for use as a dedicated parting tool holder, but decided to convert that one at the last minute into a regular holder, and cut a new blank even longer, which would have left me enough steel to do another 7 toolholders in the future - even after stuffing up this replacement part:

    tenone 1.jpg

    That was originally being made from an offcut, however on attempt number one I very carefully measured the hole at 22mm, multiple times, and then very deliberately selected a 25mm drill bit to drill it out with. Absolutely NO idea why I did that, but note the 3mm difference... I could have sleeved it, but the edge of the sleeve would have been out in the rounded section that I turned on the lathe as a last step. And given it would have taken just as long as just redoing up to the point I was, instead I designated it as a test piece for rust bluing, ground my teeth, and cut a short piece off my second one metre length of 1045, to produce the specimen you saw before. It goes in the toolpost like so, for those who care:

    tenone 2.jpg

    So back to the parting toolholder, facemilled the block to size, cut the big T-slot where the previously shown part pulls on to clamp the holder. While the DRO is set up for that operation, use a HSS endmill shank that I ground to a point on the D bit grinder to scribe the centrepoints of the Vs onto the holder for the next step. Tilt the head to 45 degrees, install 20mm endmill, touch off ever so lightly on the block, then align to a scribe mark, zero the DRO there, and proceed to cut the two Vs 100mm apart, and 11mm deep, same as the previous 8 toolholders. Take it out of the vice, try it on the toolpost just as a matter of course. The locking lever goes straight past 90 degrees rotation where all the others locked, and all the way around to the other side, such that the eccentric cam is just past full throw and returning again, and the toolholder is barely clamped. ?

    After much head scratching, and some difficulty in measurement, I worked out that the endmill had pulled about 1mm out of the collet at some point during the job, meaning that my Vs had moved over by about 0.75mm. That in itself wouldn't have been a problem, but the corresponding DOWNWARD shift of the same amount was. There are only two truly critical measurement on these toolholders - one is the distance apart of the Vs, the other is the relationship between the T-slot face where the clamp pulls on and the depth of the Vs...

    A large amount of teeth gnashing, a disgusted stomp out of the shed for the day, and a number of hours of ill temper followed that particular discovery.

    Given this was going to be a parting toolholder, and as such in constant use, I couldn't see a way to fix it that I was happy with. I could get it to lock and hold properly by using 0.8mm aluminium as shims between the clamp and holder, but figuring out a good way to attach shims or anything else got too bloody hard, so again teeth grinding ensued, holder went in the 'small scraps for later' bin, and another length was cut.

    Having squared it to size, and cut the T slot section, upon scribing my guide lines for the 45 degree step, the line looked a bit close to the edge. Sure enough, somehow or other, I'd managed to move in 55mm from the edge before zeroing the DRO for the T slot, instead of 58mm. Not sure how I screwed that up, but I'm not a fan of the number 3 at the moment. I would have just moved the Vs over that amount, but the clamp on the tool post would have fouled in the T-slot, so I just continued on. Just means the little chamfer on that edge looks different to the other toolposts, but it was kind of always going to be different anyway. It DOES however stick out 3mm further than I'd originally intended .

    portautensile per lama a troncare.jpg

    You can sort of just see that the locking pin on the toolpost is dead centre of it's rotation, but more importantly the idea behind the longer toolholder. It's 20mm 23mm longer than the regular toolholder in this direction, which means it sticks out past the clamp on the back face of the toolpost by about 13mm. Thus I don't have to run any extra stickout on the parting blade just to keep the toolpost from fouling the workpiece, and it also allows me to reach behind a shoulder or other feature to some extent.

    The other reason for a dedicated toolholder like this is so I could run a 32mm high parting tool, but keep it as close in to the toolpost as possible, rather than having to have the typical arrangement where the holder for the parting tool hangs way out the side of the toolholder, and has a lot of leverage against the toolpost stud.

    Whether it was all worth it, time will tell. Time will also tell if I make another 5 toolholders with the remaining 1045.... The knurled height adjusters are already done and on the shelf... I did 18 of those in the end, as I replaced a couple of fat awkward shaped ones on some of the old home made holders that came with the machine - I tend to pick the holders up by the height adjusters, and I've just about dropped them on my foot a couple of times due to the awkward shape, but no more.

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