Craftsman Vari-Slo Question - Model 100 Drillpress

[7th Kahuna]

Over the weekend I acquired a Vari-Slo assembly for a 1952 Model 100 Craftsman drillpress. It is missing three parts, two of which are fairly simple to replace but the third is the clamping pad. I see some folks have simply replaced it with a bolt with a longer thread, but the head casting is still so clean I'd hate to do that. It will tear it up. I have searched for information on the clamping pad but google has let me down.

Can anyone tell me anything about it? What is it made of? Is the pad round or square? Does the face have a curved surface to match the arc (matched, tighter, looser, flat) of the head casting? Does anyone have a picture of one. I figure I might be able to make something out of Teflon.

And because I know this thread is useless without pictures, here you go:

 

[nine4gmc]

Lucky you, I wish I had one to compare but mine has the stock 4spd pulleys...

 

[WWIIjeep]

IIRC, the pad is a zinc-aluminum alloy die casting, and it's round, and is not curved to the shape of the quadrant.

 

[7th Kahuna]

I was pretty happy to get it, came with a drillpress too.

But I suspect the quill has issues so it may end up being a parts machine.

I have a '58 or '59 Model 100 that had it's column cut down. I think it's going to get it's full height back.

 

[7th Kahuna]

IIRC, the pad is a zinc-aluminum alloy die casting, and it's round, and is not curved to the shape of the quadrant.

Thanks WWIIjeep. I suspect the plastics of the early 50's wouldn't have held up well. I wonder how tight it has to be to lock it in place? Hard to tell if the design offers any leverage to the clamp.

 

[WWIIjeep]

I wonder how tight it has to be to lock it in place?

Not very. You only have the leverage of the knob--a little over an inch in diameter--and even at that, you shouldn't really twist it anymore than snug.

The really critical thing with the Vari-Slo is that you not try to force it, and definitely don't move it unless the motor is running.

 

[7th Kahuna]

Not very. You only have the leverage of the knob--a little over an inch in diameter--and even at that, you shouldn't really twist it anymore than snug.

The really critical thing with the Vari-Slo is that you not try to force it, and definitely don't move it unless the motor is running.

Sounds like you might have some first hand experience with it. What do you think, would Teflon or polyethylene do the job or should I consider finding someone to turn me one out of aluminum? Sounds to me like the plastic would work. I might already have a piece of solid nylon dowel I could work with.

Thanks for the warning on adjustment. I am aware of the need to have it running. In fact, from what I have read, I actually questioned the value of the Vari-Slo. My intent has been to find the basic Multi-Speed Attachment and just do it manually, but the only one I have seen was way over priced.

 

[WWIIjeep]

Sounds like you might have some first hand experience with it. What do you think, would Teflon or polyethylene do the job or should I consider finding someone to turn me one out of aluminum? Sounds to me like the plastic would work. I might already have a piece of solid nylon dowel I could work with.

Yeah, I've had experience with 4 or 5 of them over the years, including having to fix 2 of them because the support casting that fits around the column was broken.

I don't have one right now to check the exact details, but I think the clamping pad is held on the end of the locking screw by a set screw or pin. So the question is, whether or not plastic will work that way, if that is in fact the way the clamp pad is held on.

from what I have read, I actually questioned the value of the Vari-Slo. My intent has been to find the basic Multi-Speed Attachment and just do it manually, but the only one I have seen was way over priced.

The Vari-Slo can be very handy as long as you work within its capacity. Belt slippage can be a problem, especially at slow speeds drilling metal. It may be necessary to replace your existing belts with cogged-style belts (more flexible and grip better on small pulley diameters) to get the best performance.

 

[7th Kahuna]

^ Interesting that you mention the support casting breaking. From what I have been able to discern, there are at least two versions of the Vari-Slo. The first thing I noticed different (in the drawings mind you) was they appeared to have reduced the amount of material in that casting, substituting a raised spine for a thicker body. If your memory is correct, another change seems to have been the addition of a set screw to lock the pad in place. Mine has none. There is actually nothing to keep the pad from falling away except that the 'post' behind the pad makes the total depth of the pad greater than the space between the control arm and the head casting. That's my theory anyhow. It would be nice to see one in the wild.

Thanks again for your help.

 

[Joe B.]

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[7th Kahuna]

^ thank you

 

[7th Kahuna]

For Reference:

Craftsman Part Description

Clamping Pad SR-370

 

[Joe B.]

^ thank you

No problem. I happen to have mine dissembled because of a move. That little plug falls out pretty easily and I have seen is show up a few times on forums as missing. Hopefully this helps out some other folks down the road.

 

[7th Kahuna]

I'm sure it will.

Quick question, is that something in the center of the 'post'? Can't tell if I am seeing dirt, a shadow, or a set screw.

 

[Tim338]

It looks like a easy part to make if you have a lathe. I would make it out of aluminium or brass if it was me. If you don't have a lathe let me know and I make you one.

 

[Joe B.]

I'm sure it will.

Quick question, is that something in the center of the 'post'? Can't tell if I am seeing dirt, a shadow, or a set screw.

There is nothing in the center. It is just a flat surface. That marking looks much darker in my pictures than in real life. I suspect it is just where the threaded screw pressed against it. My drill press is in almost new condition so it did not take much use the make that mark.

Also, for the historical record, my drill press is from 1958 per the date on the original manual. I think it is safe to assume that the Vari-slo was installed when it was new.

It looks like a easy part to make if you have a lathe. I would make it out of aluminium or brass if it was me. If you don't have a lathe let me know and I make you one.

I would take Tim up on this generous offer! I think I have all of the dimensions shown. Let me know if you need anything else.

 

[torqueman2002]

Thank you for solving a mystery for me.

This part fell on the ground when I unloaded my CM 150 DP with Vari-Slo. I had no idea what it was for until this thread.

The PO used bolts to tighten the Vari-Slo.

 

[7th Kahuna]

It looks like a easy part to make if you have a lathe. I would make it out of aluminium or brass if it was me. If you don't have a lathe let me know and I make you one.

Tim, I would really appreciate that. I figured plastic I might be able to do with a dowel cutter and a drill press but I don't currently have any means to make one of metal.

 

[7th Kahuna]

There is nothing in the center. It is just a flat surface. That marking looks much darker in my pictures than in real life. I suspect it is just where the threaded screw pressed against it. My drill press is in almost new condition so it did not take much use the make that mark.

Good to know. I couldn't figure how it would have functioned if there had been something there.

I would take Tim up on this generous offer! I think I have all of the dimensions shown. Let me know if you need anything else.

There are some terrific folks on this board. Yourself included. Thanks again.

Thank you for solving a mystery for me.

The PO used bolts to tighten the Vari-Slo.

I'm glad you didn't toss the pad. I purchased mine at an estate sale. The drill press had been moved around a bit. I'm sure the part fell out and is sitting on a counter somewhere and nobody knows what it is.

I have seen a couple of these with that pair of bolts. The only purpose I can see for the lower bolt is to provide leverage while adjusting the speed. Originally that lower bolt would have just been a set screw used to adjust and lock the position of the Vari-Slo to the head casting. You can see it in the drawing at the top of the thread.

 

[Tim338]

Tim, I would really appreciate that. I figured plastic I might be able to do with a dowel cutter and a drill press but I don't currently have any means to make one of metal.

PM me your address and I will get on it. Might be a few days before I get to it. But when I get it done I will mail it out.

 

[Tim338]

I lied, I did manage to get it done today. I made it from 6061.

 

[Joe B.]

I lied, I did manage to get it done today. I made it from 6061.

That is very cool and generous of you. Nice looking work.

 

[Tim338]

Thanks, I like to help a guy out every once and a while. Just waiting for an address so I can get it sent out.

 

[7th Kahuna]

PM me your address and I will get on it. Might be a few days before I get to it. But when I get it done I will mail it out.

Message Sent.

I lied, I did manage to get it done today. I made it from 6061.

Looks great. Thanks again.