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  1. #46
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    Hi Mathu, Guys,

    Thanks for the video !

    That tool you have made would be the right shape for a form tool. However that wasn't what I meant when I said about a radius on the nose of the tool. The radius would only be 0.25 mm to maybe 0.75 mm and would not create flats on the nose of the tool. The radius would follow the clearance angles so you would still have a very sharp cutting edge. This is normally done by hand using a fine stone. Mine is around 400 grit ! You have to be very careful not to rub the sharp edge off, or groove the stone.

    One other thing that strikes me is the rotational speed ! A large diameter needs to be turned slower than a small one. Its actually harder to get a good finish if the workpiece is running too fast.
    Best Regards:
    Baron J.

  2. #47
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    Looks pretty good. I have noticed scratches can appear much worse in pictures than in 'the flesh'. I have taken a pic of a job that looked near perfect and found it looked scratched when uploaded to the forum. Might be something to do with the way the camera converts the raw image into a jpeg file? Photography is not my thing.
    Chris

  3. #48
    BobL is offline Member: Blue and white apron brigade
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    Not seeing scratches usually a lighting issue. I used to take things outside to see scratches until I installed my 4000 lumen LEDs above my lathe but even that is not enough. Assuming everything else is equal, which it probably isn’t, When you’re over 60 you need twice as much light to see what a 20 yr old sees.

  4. #49
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    186518786_540003296995434_5572078766478204698_n.jpg



    getting better, i think it's my sanding that's putting marks in the workpiece :/ hmm.

    otherwise they are coming out okay.

  5. #50
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    Doesn't look like sanding marks to me. Pretty hard to tell exactly whats going on once you've sanded it, try taking an 'as turned' photo before sanding it. Might give us some more clues as to what is happening.

    How are you doing the tapered parts? The finish makes it look like you're freehanding it by moving the carriage and the cross slide at the same time, lots of little stairsteps in it. Very hard to avoid when freehanding, requires far more co-ordination than I possess.

    If you're doing it by rotating the compound slide and using that, something is definitely moving. My best guess would be you need to adjust the gibs on the compound and cross slide, do a Google search on adjusting South Bend gibs to find out how to do it on your machine.

    If your gibs aren't tight enough, particularly the compound slide could be moving sideways on the slideways as you go. If it's loose enough, you turning the handwheel on the compound could be enough to wobble it side to side, changing your depth of cut. Which might explain why the effect is worse on the tapered section (assuming you're using the carriage to do the straight portions).

    Either way, well worth spending the time to make sure the gibs are adjusted as best as you can, one less variable to deal with. The finish on the straight portion is hard to pick exactly what is happening post sanding, but the bigger part looks like it might have a bit of tearing going on still, which could be speed/tool geometry/lack of cutting lube. There also appear to be a couple of sharper gouges which might come back to gib adjustment, or something flexing. Very difficult to say exactly without being able to put hands on your machine and feeling/seeing/hearing what it's doing.

    Do local TAFEs still offer those relatively affordable night time 'intro to machining' type courses? Just thinking given no-one has volunteered to give you a hand, might be worth the investment. If you can grind a tool at the TAFE course, and get a good finish on the machine there, you've got a good frame of reference. If the same tool and steel taken home then doesn't give the same result, you know you need to delve into sorting out whatever issues your machine may have. A few hours 'hands on' with some decent guidance equals many many hours of reading and experimentation at home, particularly in the early stages of this game.

    *edit* There IS a way to get rid of a lot of the marks, and blend the stair-step effect out, but I'm a bit hesitant to suggest it given your level of experience, and likely some shouts of horror from other posters. Nonetheless, watch enough Youtube videos and you'll discover this trick for yourself, so use of a flat fine cut file on the part whilst it's spinning in the lathe is a very effective method failing all else. If you attempt this, be VERY aware of the serious danger involved, particularly with respect to what happens if you stick the tip of the file into the jaws - or your knuckles/fingers. I often tend to run the spindle in reverse if I need to file something close to the jaws, and hold the 'wrong' end of the file with a light grip, so that if it were to be grabbed it most likely gets thrown away from me. Still requires acute awareness of where your hands are though, and it's far preferable to get a good finish straight off the tool and keep the filing trick for minor deburring/blending of edges/radii rather than bulk removal.

  6. #51
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    Quote Originally Posted by Jekyll and Hyde View Post
    Doesn't look like sanding marks to me. Pretty hard to tell exactly whats going on once you've sanded it, try taking an 'as turned' photo before sanding it. Might give us some more clues as to what is happening.

    How are you doing the tapered parts? The finish makes it look like you're freehanding it by moving the carriage and the cross slide at the same time, lots of little stairsteps in it. Very hard to avoid when freehanding, requires far more co-ordination than I possess.

    If you're doing it by rotating the compound slide and using that, something is definitely moving. My best guess would be you need to adjust the gibs on the compound and cross slide, do a Google search on adjusting South Bend gibs to find out how to do it on your machine.

    If your gibs aren't tight enough, particularly the compound slide could be moving sideways on the slideways as you go. If it's loose enough, you turning the handwheel on the compound could be enough to wobble it side to side, changing your depth of cut. Which might explain why the effect is worse on the tapered section (assuming you're using the carriage to do the straight portions).

    Either way, well worth spending the time to make sure the gibs are adjusted as best as you can, one less variable to deal with. The finish on the straight portion is hard to pick exactly what is happening post sanding, but the bigger part looks like it might have a bit of tearing going on still, which could be speed/tool geometry/lack of cutting lube. There also appear to be a couple of sharper gouges which might come back to gib adjustment, or something flexing. Very difficult to say exactly without being able to put hands on your machine and feeling/seeing/hearing what it's doing.

    Do local TAFEs still offer those relatively affordable night time 'intro to machining' type courses? Just thinking given no-one has volunteered to give you a hand, might be worth the investment. If you can grind a tool at the TAFE course, and get a good finish on the machine there, you've got a good frame of reference. If the same tool and steel taken home then doesn't give the same result, you know you need to delve into sorting out whatever issues your machine may have. A few hours 'hands on' with some decent guidance equals many many hours of reading and experimentation at home, particularly in the early stages of this game.

    *edit* There IS a way to get rid of a lot of the marks, and blend the stair-step effect out, but I'm a bit hesitant to suggest it given your level of experience, and likely some shouts of horror from other posters. Nonetheless, use of a fine cut file on the part whilst it's spinning in the lathe is a very effective method failing all else. If you attempt this, be VERY aware of the serious danger involved, particularly with respect to what happens if you stick the tip of the file into the jaws - or your knuckles/fingers. I often tend to run the spindle in reverse if I need to file something close to the jaws, and hold the 'wrong' end of the file with a light grip, so that if it were to be grabbed it most likely gets thrown away from me. Still requires acute awareness of where your hands are though, and it's far preferable to get a good finish straight off the tool and keep the filing trick for minor deburring/blending of edges/radii rather than bulk removal.


    Thank you great information. yeah, i have noticed the saddle/ coss slide and compound, when force from the workpiece puts pressure back on the tool it can and does move from time to time.

    okay i'll look into the gibs.

    Yes, i am freehanding the whole piece

    i'll also look into some cutting liquid

  7. #52
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    Quote Originally Posted by mathuisella View Post
    Thank you great information. yeah, i have noticed the saddle/ coss slide and compound, when force from the workpiece puts pressure back on the tool it can and does move from time to time.

    okay i'll look into the gibs.

    Yes, i am freehanding the whole piece

    i'll also look into some cutting liquid
    If you're freehanding the taper you're setting yourself a very difficult goal to get a smooth seamless surface there. Certainly can be done with enough skill and practice, but far easier for mere mortals like me to rotate the compound and use that for tapers where possible. May require you to go without the live centre, which shouldn't be much of an issue with your current workpiece lengths as long as you don't get crazy with the depth of cut (and assuming the spindle bearings aren't worn or loose).

    While you're looking up gib adjustments, look up what slide locks you have at your disposal, and use them whenever possible. Different machines have different amounts of locks - my old AL335 had locks on every slide, so I kept the compound locked whenever not using it, and locked the carriage for parting off. If using the compound, I'd normally lock the cross slide and carriage. The Graziano only has a lock on the carriage, and I have to lock the compound by tightening the gib right up (otherwise it creeps back while cutting). The aim of the game is to reduce any movement to the minimum viable.

    For radiused sections, a form tool is often used on bigger machines, but that is likely going to be a bit of a problem with your machine without using a few tricks on anything other than a pretty small radius (3-4mm maybe? Depends on a few things), and grinding them is going to be a bit difficult freehand. As the length of cutting edge engagement increases, the amount of rigidity required also increases dramatically. A ball turning tool/attachment solves that issue, and I think would be the best bet for your machine if you wish to do various radii on a regular basis. Can be bought or made, plenty of plans/pictures on the interwebz.

    In terms of cutting liquid - if you just want a little bit of something something to try out and see if it helps first, Bunnings and Total Tools list Suttons 'Venom' for $15 for 250ml. Should work well, given one of the use cases on the bottle is for endmills, and I seem to remember someone on here being fairly impressed with it at some point.

    A cheaper option is you can buy 'thread cutting oil' for use in pipe threading machines fairly easily in 5l containers at a not horrendous price, which I think is what a lot of US machinists use. Think Total Tools list Ridgid brand 'Dark' threading oil for about $42 (special order) for example. Haven't got around to getting some myself, as I run carbide and generally don't have that much use for it, so no idea how well it works, but it should be pretty good (although may stain stainless steel and some other things being the 'dark' type, but they've reformulated it some years back so who knows). Sydney tools list Ridgids 'Nu-clear' for $38 if you wanted something that shouldn't discolor any metals, but looks like its mail order only. Gives you an idea of how much it 'should' be in that size anyway (I've seen some threading oils for in excess of $100 for 5l, which may or may not perform better than the others).

    There are also the 'old school' options, like lard. Seems like a biohazard waiting to happen after it's been festering in corners of the machine to me, but apparently works very well. Not sure on the details, think it gets mixed with something else. Not sure if you can just use a $4 200g jar from Coles, or whether you need to eat lots of bacon...

    Any number of other options exist of course, those are just the cheap and easy to get options that I know of. Just be aware if you're getting some/most of these fluids hot enough to make smoke, they may be emitting some fairly nasty byproducts, and even in 'normal' conditions you may want to consider your ventilation etc. One of the reasons I tend to stick with running dry carbide mostly.

  8. #53
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    I think i figured it out. the compound/cross slide move back a little bit, so i gotta tighten up/adjust the gibs. I don't think there's a way for me to lock the cross slide on my lathe ( hercus / south bend model C )

    but when it's all seemingly going well and no chatter, the whole lathe cabinet with lathe bolted upon it wobbles very very slightly, almost un-noticable when there's a load from the tool to the workpiece.

    I cant bolt it to the floor though as i'm renting this place :'(

  9. #54
    Join Date
    Sep 2012
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    York, North Yorkshire UK
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    Hi Guys,

    Non of my machines are bolted to the floor ! I use pieces of old conveyor belting to stand them on. The rubber belting absorbs small dips and bumps providing a good surface for them to sit on !
    Best Regards:
    Baron J.

  10. #55
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    Quote Originally Posted by BaronJ View Post
    Hi Guys,

    Non of my machines are bolted to the floor ! I use pieces of old conveyor belting to stand them on. The rubber belting absorbs small dips and bumps providing a good surface for them to sit on !

    Ohh thank you

    any chance of a picture or two ?

    do you put a square piece under each " leg" of your lathe, or cabinet on which the lathe sits upon ?

    or a single big length ?


    any ideas where i could find such a material ? i'm not near a mining town lol ? what thickness is it ? and is it neoprene or does it have sewing/linings through it ?


    how about cutting sections from an old tyre ?

    I found a 4mm thick rubber mat near me that would fit my entire lathe over it 2metres long x 1metrewide x 4mm thick

  11. #56
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    Sep 2012
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    York, North Yorkshire UK
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    Hi Mathu, Guys,

    All the rubber belting is 1/2" or 5/8" inch thick. My local scrapyard has miles of the stuff, varying from a couple of feet wide to well over six feet wide. Most of it came from the mining industry, either as scrapage or replacement.

    I just went and was allowed to just take what ever I wanted, free of charge. Basically they can't get rid of it, no one wants it. Be aware that its tough stuff and very heavy. I used a wetted Stanley knife and a steel rule to slice pieces off.

    When cutting it to size when you get it home use some washing up liquid in the water, it makes it a lot easier to cut. All mine has a canvas core, but some has a thin wire mesh core and is almost impossible to cut without a shear/guillotine.

    As far as pictures, yes I can take a picture , but I doubt that it would tell you much other than the whole machine sits on it and makes sweeping up swarf and stuff easy ! However avoid getting any oil on it. It doesn't seem to affect the rubber but creates a real slip hazard. I use a degreaser to clean any drips up.

    26-05-2021-002.jpg 26-05-2021-001.jpg

    Will these do ? One under the mill and the one under the lathe.
    Best Regards:
    Baron J.

  12. #57
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    Quote Originally Posted by BaronJ View Post
    Hi Mathu, Guys,

    All the rubber belting is 1/2" or 5/8" inch thick. My local scrapyard has miles of the stuff, varying from a couple of feet wide to well over six feet wide. Most of it came from the mining industry, either as scrapage or replacement.

    I just went and was allowed to just take what ever I wanted, free of charge. Basically they can't get rid of it, no one wants it. Be aware that its tough stuff and very heavy. I used a wetted Stanley knife and a steel rule to slice pieces off.

    When cutting it to size when you get it home use some washing up liquid in the water, it makes it a lot easier to cut. All mine has a canvas core, but some has a thin wire mesh core and is almost impossible to cut without a shear/guillotine.

    As far as pictures, yes I can take a picture , but I doubt that it would tell you much other than the whole machine sits on it and makes sweeping up swarf and stuff easy ! However avoid getting any oil on it. It doesn't seem to affect the rubber but creates a real slip hazard. I use a degreaser to clean any drips up.

    26-05-2021-002.jpg 26-05-2021-001.jpg

    Will these do ? One under the mill and the one under the lathe.
    Thank you.

    i found some conveyer belt 12 mm thick 200mm wide and about 10 metres of the stuff.

    So i'm thinking i cut it up and put some under each post/leg of the lathe's cabinet

  13. #58
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    Quote Originally Posted by mathuisella View Post
    Thank you.

    I found some conveyor belt 12 mm thick 200mm wide and about 10 metres of the stuff.

    So i'm thinking i cut it up and put some under each post/leg of the lathe's cabinet
    Hi Mathu, Guys,

    You will find that if its clean, gaffer tape, the cloth stuff will join pieces together without any fuss !

    As you can see in the pictures I have mine extended out well in front of the machines, it is much nicer to stand on in winter when the floor is icy cold.
    Best Regards:
    Baron J.

  14. #59
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    Quote Originally Posted by BaronJ View Post
    it is much nicer to stand on in winter when the floor is icy cold.
    Maybe one of these John? https://www.bewarmer.co.uk/
    Chris

  15. #60
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    So i got myself some rubber matting
    feels nicer to stand on that's for sure.
    As you can tell i've been using the lathe a bit... Also that's the GMC grinder that smoke came out of :'(

    the matting was 1200*1700*10 and cost $25. it fits nicely under all 4 legs and i don't hear the lathe machine bounding/vibrating on the concrete anymore. I still feel it needs to be weighed down though. ( bolts to the floor would be best but i cant )
    196370815_236027307990123_3367525255444109091_n.jpg







    As you can see in this picture i'm using a brazed carbide tool and it works very well at removing material and leaving a pretty nice finish.
    198646887_267051945217739_8039311089065180746_n.jpg



    After it's all said and done, i sand it all and it finished up looking like this compared to the old one. I believe it's a bit better Note: sanded down from 180 to 2000 grit sand paper.





    194238914_549239736458989_2857886596862305643_n(1).jpg197189617_483398322726416_951264615408267653_n(1).jpg

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