Rounding slitting saw cutters

I need to make a thin slot that has a "U" profile. I was thinking about rounding slitting saw by running it in reverse and knocking the edge off with a stone. And then removing the burr with a hone if it forms.

Will this work?

Thanks, Alex

Reply to
Alex
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You will lose the saw kerf . I would cut almost all the way first , then do the rounding and finish the very bottom of the cut . After that the saw will be pretty much useless for cutting . Should work fine for a one off though . Luck Ken Cutt

Reply to
Ken Cutt

Hi Alex I don't exactly know what you are trying to achieve but I think it would be to mill a slot for a woodruff key ( a moon shaped key usually found on tapered shafts ) If this is the case Woodruff cutters can be begged, stole, or borrowed and are used as an end mill or slot drill would be mounted. If this isn't the case the method that you are suggesting would work but you would have to make sure that you ground sufficient clearance on each cutting edge. I hope this has been of some help to you, if not, and you think I may be able to help you can e-mail me at snipped-for-privacy@hotmail.co.uk

Reply to
paul.makin

Not really.

When you round the corners over, the teeth will have zero clearance.

This means that as the work is fed into the cutter, the the teeth will rub against the work, instead of cutting it.

The teeth on your slitting saw are composed of two ground faces (if not more) - rake and clearance. The rake face is the one over which the chip slides as it is cut. The trailing face which "gets out of the way" of the material being fed into the cutter is the clearance face. I can't really explain it to you without a picture, but *all* cutting tools have these faces. Turning tools, endmills, slitting saws, facemills and flycutters, drill bits, boring bits, counterbores, countersinks, etc.

Without clearance you rub. As you feed, the saw will flex and likely break. Sometimes such abominable cutting conditions "work" (just barely) in soft materials with very rigid cutters, powerful machines and good sense/experience, but I'd imagine you won't be successful.

Regards,

Robin

Reply to
Robin S.

Well, the rounded edge won't have any relief and won't cut very well, depending upon the radius of the corner. Bigger is worse. If you're putting the slot in aluminum or brass it won't matter nearly as much as in steel. Bob

Reply to
Bob Engelhardt

Can you drill a hole and then slit up to the center of the hole?

Reply to
tomcas

Good idea, but won't work in my case.

Reply to
Alex

Cut it with a regular end mill and finish the bottom with a round ended mill ?

Reply to
Snag

It will work. To make it dull an useless. :-) Go to a T&C-grinder. He will make that job for you. Don't know what he will ask for, maybe $30..40?

If you don't want to spend that money, you can do it, but different: You have to stone that radius on every tooth by hand. Work from the side of the blade. You see the relief of the teeth and you have to keep it when stoning them round.

Nick

Reply to
Nick Mueller

How wide? How deep? Randy

Reply to
Randy Replogle

0.030" wide, 0.040" deep
Reply to
Alex

Shaper!

Nick

Reply to
Nick Mueller

Flycutter.

John Martin

Reply to
John Martin

I'm going to leap in here and say "do it". Run the saw backwards at normal speed 50-80fpm oil it well and use the edge of the stone. You will wear several grooves in the stone and it will take a bit of time. To put this into context, I cut 2 feet of slot in 1/4" steel plate last week with a 5" slitting saw that I had "freshened" the rounded teeth on by this technique. Although I kept the teeth square, rounding them won't affect the rake enough to stop them working.

Mark Rand RTFM

Reply to
Mark Rand

Rounding the teeth won't affect the rake *at all* and we're not worried about the rake anyway. It's only the clearance that would suffer as a result of this abuse. As I understand, jeweler's slitting saws break easily under the best conditions. Rounding the teeth and not adjusting the clearance appropriately is not even close to ideal, and indeed a vast leap from "rounding" the edges of the teeth on a

5" (how wide was it?) slitting saw.

I like Nick's suggestion of stoning clearance on to every tooth. Perhaps it would take 15min, but a lot faster than making a trip to the local tool supplier (and that tool wouldn't be standard anyway). A flycutter is another excellent suggestion. A bit of a trick to grind the tool, but you're home free once it's done, and it will cost only time.

Regards,

Robin

Reply to
Robin S.

I'll give you one of my 144 teeth slitting saws and sit by drinking a beer or two or three ... :-)

Nick

Reply to
Nick Mueller

O-ring groove.

Gunner

Political Correctness

A doctrine fostered by a delusional, illogical liberal minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.

Reply to
Gunner

Slitting saws shouldn't have a set on the teeth at all. The clearance is ground into the saw... the hub is a thou or so thinner than the periphery. a saw with all of the clearance on the teeth would not be very re-sharpenable. In this particular case (shallow groove), clearance isn't necessary at all anyway.

Regards Mark Rand

Reply to
Mark Rand

Mark, I'm referring to what the Machinery's Handbook calls "radial relief" on the tooth's land, and the "clearance surface", called the heel. I tend to call the whole thing just "clearance" but "relief" would be more correct.

All cutters have rake and relief. Everything else is just a special adjustment of either of these general qualities of a cutting tool.

What you're referring to is called "axial relief" and is of no consequence in this situation.

Only the radial relief is removed by rounding the edges of the teeth in the manner being discussed. The rake remains untouched, and you're right that there is no axial relief in a jeweler's slitting saw. Radial relief is required to allow the cut to occur. Removing it will cause the teeth to rub, and not cut.

Regards,

Robin

Reply to
Robin S.

Not very deep, try several passes with a ball endmill.

Reply to
ff

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