Slitting saw

[stephenc]

Someone school me on slitting saws .

I need to cut a slit in some 7/8 dia 01 tool steel
The slit can be anywhere from .030-075 wide and will be about .680 deep .

Is this feasible with a slitting saw , and what should I be looking for as far as tooth count . And name brands .

I won't say money is no object , but I'd much rather spend a few bucks and be successful .

I know zero about slitting saws ... absolutely zero .

[Dave_C]

Well, from the info given I'd say maybe because you don't say how long this slot would be. It may not be the best use of the saw but I've used them for odd jobs like this and if you have a good blade and arbor you can make some good cuts. Holding it solid is key as well. It can't be bending while you're trying to slot it with a saw and given that you might be using a mill to run the saw, holding it while you cut from the side might be the challenge. Maybe you have a horizontal setup?

.680" deep is pretty deep for a 7/8" rod!

Maybe someone else can offer some better advice but if you have a good arbor the saws blades are not expensive! Good arbors can be though.

Dave C.

[stephenc]

The slit will across the bar not lenght ways .. so 7/8 of an inch

I had planned on making my own arbor

To hold the work my plan is to simply bolt a lathe Chuck to the table . The piece is fairly short

[mcostello]

Not going to take it all in one cut, are You?

[Harold_V]

Slitting saws have side cutting surfaces, while screw cutting saws have none, although they have a slightly concaved grind to yield minor relief. You don't really want the entire blade in contact with the resulting slot.

Because of the depth involved, the teeth will be in contact over a fairly large area. That's assuming you take the cut in one pass (which most likely would work just fine). As a result, you would be best served to procure a blade with coarse teeth, which likely eliminates a screw slotting blade. The prolonged cut will generate a large volume of chip, which can fill and overwhelm the gullet in fine toothed cutters.

Mind surface speed. A cutter large enough to achieve the depth you require must be run quite slowly, the speed being determined by the diameter of the cutter, and the acceptable surface speed for the given material. It will seem very slow, but, especially in tool steel, it must be.

Don't climb cut. That's a recipe for disaster. Lubricate well during the cut. And, remember, you'll be using a tool with multiple teeth, so feed rate may seem unreasonably fast. Make sure you're taking at least a thou per tooth, otherwise the blade will rub and not perform well.

It likely stands to reason that the wider the blade, the more stable it will be. Narrow blades will often favor one side and create a less than true path. Make sure the blade is sharp, with no damaged edges, which will readily deflect the cutter.

Oh, yeah! Keep your fingers and acid brush out of the cut. Not doing so tends to have a way of ruining your day.

If the cut is across the end of the piece in question, no reason why you can't hold it in a vise. It wouldn't be nearly as difficult to set up. That's assuming the piece is long enough to grip. If it's short, use an identical diameter at the opposite end of the vise, so the vise jaws must grip parallel. It should be very short, and near the opposite edge, so the majority of effort is concentrated on the object being machined.

H

[RSG]

That's well dispensed advice Harold!

Other than I'd like to know your thoughts on why you shouldn't climb cut with the saw? In my mind the blade thickness he wants to use would be rigid enough and wouldn't it labour and dull faster conventional cutting?

[WJH]

I once tried to do a deep cut with a screw slitting blade. The blade now has a rounded top edge, and is garbage.


Sent from my iPhone using Tapatalk Pro

[earlgo]

Hang on to your pucker strings.
I have made cuts similar to this in one pass using the Delta T&C grinder and a 7" .030 thick cutoff wheel. Makes a lovely yellow light and one needs a handy fire extinguisher. Once it is de-burred, the cut itself is quite smooth.
Release...
--earlgo

[Dave_C]

Don't climb cut. That's a recipe for disaster

Most of our manual mills have enough backlash to let the saw grab and given the number of teeth in the cut it can grab quite vigorously! Even to the point of pulling the piece out of the clamping device.

I'm a bit confused over the "putting it in a lathe chuck clamped to the table" as that would make the piece stick straight up if my minds eye is following this procedure.

If the OP wants to cut across the end of the 7/8" piece then I suggest putting it in a mill vise and do it as Harold suggested.

Dave C.

[John Hasler]

I've made cuts that deep with a screw cutting blade (but in mild steel). The key is that the passes must be no deeper than the gullet (but deep enough not to rub).

Since you've got lots of money don't cheap out like me. Buy real slitting saws. And make sure your arbor is very, very concentric.

[warmstrong1955]

I agree with not cheaping out. I bought an arbor and a couple of blades from Enco, to build a bunch of TPS levers. All mild steel. No problems at all, and I made about 30 of ‘em.

I had a project come up where I needed to slit some 4140 Q&T (prehard) and didn’t get past one slit, and the blade was dull. I changed blades, and dulled it right away too.

Bill

[stephenc]

I really like Harolds advice .. clear concise and super easy to understand.
If I was a tenth as clear as he is on what I want to do life would be good .

So knowing I was as clear as mud ... the reason for the lathe Chuck .
I want the piece to be sticking straight up . It puts the work in proper relation to the cut i want to make .
If I use a vice I will have to tilt the head 90 degrees

Earlgo mentions using an abrasive cut off wheel , this is a route I hadn't considered
And it might be the easiest .
I have a surface grinder and the actual width of the slot isn't critical just so it isn't to wide or narrow .
What I am looking for is a slot cut as " square " as possible which is why I don't simply cut it in the power hack saw .