Hand Slotter.

[BaronJ]

One of the things that I am going to make based on recent experience with making replacement mill gears and the mill table traverse drive is a hand slotter to make keyways in pulleys. Using the saddle on the lathe is hard work and very time consuming not to mention the wear that this must produce winding the saddle up and down in one spot, so I thought that making a device to go onto a QCTP would be a good Idea. Then the saddle can be locked in place and the wear avoided. Plus the extra leverage of a long handle must make it easier.

[Bryan]

I made one of those once. It was disappointing.
Then I got a shaper. It never disappoints.

[franco]

BaronJ,

I fabricated one of these using the dimensions from an article in MEW August-September 1991 which described building one from a set of castings. If you can find a copy of this article it provides a good starting point. It is wonderful for 1/8" and 3mm keyways, and has cut quite a number of these, but see posts 16 and 19 in this thread for photo and further comments:

http://www.practicalmachinist.com/vb...5/#post1547213

I did cut a 3/16" internal keyway 2" long in steel with it when building the Blanchard lathe, but this was hard work! Still better than traversing the carriage though.

Frank.

[Michael G]

I bought a set of second hand broaches to get around the keyway thing. While I have a shaper that I could use for small keyways in gears, handles etc it does a very good job. I push them through with a 10t hydraulic press. Occasionally I need to make up a bush for a bore but the cutting tools are fine. One benefit I have found with buying second hand sets is that people tend to put extra bits in there so while originally the set may have come with say 4 broaches mine arrived with 6.

Michael

[PDW]

I bought a set of second hand broaches to get around the keyway thing.

I bought a slotter but then I've done 1 keyway less than 6mm in the last 15 years and that only 2 weeks back. More like a 10mm key in 100mm of cast iron for my usual work sizes.

I think I might have a broach or 2 from 15+ years ago taking up space. I'll have a look - if I remember in 2 months when I get back to the shop.

PDW

[BaronJ]

BaronJ,

I fabricated one of these using the dimensions from an article in MEW August-September 1991 which described building one from a set of castings. If you can find a copy of this article it provides a good starting point. It is wonderful for 1/8" and 3mm keyways, and has cut quite a number of these, but see posts 16 and 19 in this thread for photo and further comments:

http://www.practicalmachinist.com/vb...5/#post1547213

I did cut a 3/16" internal keyway 2" long in steel with it when building the Blanchard lathe, but this was hard work! Still better than traversing the carriage though.

Frank.

Hi Frank,

Thanks for the link. That design is similar to the one I've started making. Mine is intended to handle a 5 mm wide key and has a much shorter stroke about 40 mm. I used one of the tool holders from the QCTP that I made a little while ago. I'll post some photographs when I get chance.

[Anorak Bob]

Baron J,

Have a look at this old thread where you will find more interesting information regarding hand slotters as made by Frank and Bryan along with a link showing the handiwork of bloke in the UK called Rob. http://www.woodworkforums.com/showth...28#post1259028

Bob.

[Bryan]

Thanks Bob, I thought I had posted that but couldn't find it. I searched for 'slotter' but didn't think of 'slotting'.
(Another vote here for predictable thread titles.)

[BaronJ]

Baron J,

Have a look at this old thread where you will find more interesting information regarding hand slotters as made by Frank and Bryan along with a link showing the handiwork of bloke in the UK called Rob. http://www.woodworkforums.com/showth...28#post1259028

Bob.

Thanks Bob,
A very interesting thread. Its a pity there isn't something about the shape of the tool required for cutting simple slots. The handle on mine will be horizontal and apart from the fact that mine will use a rectangular 12 mm by 10 mm ram, not a lot different.

One thought did occur to me that it would be useful for making calibration marks on dials and such.

[Anorak Bob]

Thanks Bob,
A very interesting thread. Its a pity there isn't something about the shape of the tool required for cutting simple slots. The handle on mine will be horizontal and apart from the fact that mine will use a rectangular 12 mm by 10 mm ram, not a lot different.

One thought did occur to me that it would be useful for making calibration marks on dials and such.

BaronJ,

Too much rooting around for calibrating. A saddle stop and a single point threading tool tipped on its side will suffice.

BT

ps. and Bryan. I'd be more guilty than anyone as an originator of obscure thread titles. Might sound clever at the time but it sure makes successful searching down the track near on impossible.I'm attempting to cut it out.

[BaronJ]

BaronJ,

Too much rooting around for calibrating. A saddle stop and a single point threading tool tipped on its side will suffice.

BT

ps. and Bryan. I'd be more guilty than anyone as an originator of obscure thread titles. Might sound clever at the time but it sure makes successful searching down the track near on impossible.I'm attempting to cut it out.

With respect to the title, since I can't go back and change it the moderator might be able to. If so then changing the word "Slotter" to "Slotting" if it is a more appropriate one.

[Bryan]

With respect to the title, since I can't go back and change it the moderator might be able to. If so then changing the word "Slotter" to "Slotting" if it is a more appropriate one.

No I think slotter is perfect. And I really should have thought to try slotting - that's more a case of user dimness on my part. And I find your posts very clear BTW.

Thanks Bob,
A very interesting thread. Its a pity there isn't something about the shape of the tool required for cutting simple slots.

Picture a parting tool. Reduce the front clearance because it doesn't need to feed during the cut. A couple of degrees should do. This will give the edge good support, allowing generous top rake, which will help your arm. I would start at full width but be prepared to narrow it down if the forces seem too high. Obviously the more rigidity you can muster in your setup the better.

[BaronJ]

Hi Guys,

It's been a bit hectic last couple of days, but as promised I did take some photographs.

Hand_Slotter-01.jpg Hand_Slotter-02.JPG Hand_Slotter-03.jpg Hand_Slotter-04.JPG

The first picture shows the QCTP that fits on the Myford toolpost in place of the original lantern and later square four tool ones.
A QCTP tool holder was pressed into service to form the body of the hand slotter. I cut a couple of pieces of 32 mm by 6 mm flat mild steel bar to form the wings. The wings were set at 30 degrees so that the pivot point was 20 mm behind the tool holder. I clamped the two pieces together and cut the ends with a hacksaw. I marked out and drilled the five holes 3.2 mm diameter. The tapping size for M4. Then using the wings as a drilling guide, drilled 3.2 mm right through the tool holder. I opened out the holes in the top of the wings to 6 mm.

The eagle eyed amongst you will notice another hole and two missing cap head screws. This was because the screw heads extended about three quarters of a millimetre outside the edge of the tool holder and I have to put a recess in the wings to clear them. I also had to shorten those two screws because the holes through the wings went through right where those two screws were.

Hand_Slotter-05.JPG Hand_Slotter-06.JPG Hand_Slotter-07.JPG

I made the ram from an old taper key that I found lying about. I milled the taper off and made it parallel to the bottom also reducing its hight to 10.5 mm and its width to 12 mm. I then set it up in the four jaw chuck and drilled a hole in the end to take a short length of 5 mm square tool steel. I cross drilled and threaded to put grub screws in top and bottom. Since I had a pair of 1/4" Whit X 1/4" allen grub screws just laying on the bench I used those. You will notice the brass shim under the ram. There is going to be one at the top but for some reason I haven't quite taken enough off, either the tool holder slot or the thickness of the ram. The tool holder slot should be 12 mm deep and 12 mm wide. So I've that to sort out.

Well that all I've done so far. I'll post more later.

Thanks:

[Anorak Bob]

BaronJ,

Looks good so far.

Something maybe worth considering is a way of providing a means of adjusting the play between the ram and housing. If the folded brass strip was either backed by a thicker piece of flat bar or even replaced with one solid piece of brass bar, then a couple of socket set screws installed from the rear face of the dovetail mount and bearing on the flat bar would facilitate some adjustment. Better though if you could incorporate this in your top plate design so you could make adjustment without having to remove the entire assembly from the QCTP.

Baron's Slotter.jpg

Bob.

[BaronJ]

BaronJ,

Looks good so far.

Something maybe worth considering is a way of providing a means of adjusting the play between the ram and housing. If the folded brass strip was either backed by a thicker piece of flat bar or even replaced with one solid piece of brass bar, then a couple of socket set screws installed from the rear face of the dovetail mount and bearing on the flat bar would facilitate some adjustment. Better though if you could incorporate this in your top plate design so you could make adjustment without having to remove the entire assembly from the QCTP.

Baron's Slotter.jpg

Bob.

Hi Bob,
You must be a mind reader. I completely agree !
I had intended to do just that. I don't particularly want to go from the dovetail side. I thought that I had measured the thickness of the ram correctly to allow for twice the thickness of the brass shimming, which is 1/16" thick. I think that I made a mistake when converting to metric. Anyway I have found some brass grub screws (I reckon they must be as rare as hens teeth) I'm not going to bother thinning off the ram. I'll just drill and thread a couple of holes in the top plate and use the brass grub screws directly on to the top of the ram. If I'm lucky I might be able to put locknuts on there as well.