Safe use of a slitting saw.

Discussion on all milling machines vertical & horizontal, including but not limited to Bridgeports, Hardinge, South Bend, Clausing, Van Norman, including imports.

Moderators: GlennW, Harold_V

earlgo
Posts: 1794
Joined: Sat Jan 29, 2011 11:38 am
Location: NE Ohio

Re: Safe use of a slitting saw.

Post by earlgo »

Success was had with a setup like this. The saw was about .040 thick. Just used standard cutting speeds and fed it slowly.

Image

Made 4 slots and didn't hurt anything, including my friend's saw.

--earlgo
Before you do anything, you must do something else first. - Washington's principle.
Glenn Brooks
Posts: 2930
Joined: Mon Nov 10, 2014 1:39 pm
Location: Woodinville, Washington

Re: Safe use of a slitting saw.

Post by Glenn Brooks »

This seems to be an old thread, but I will ask anyway...

I just bought a couple of 3" slitting saws from Grizzly tools, and tried one out this afternoon - cut off a small 2" part I shaped to replace a thumb nut from a bloc of 4" mild steel. So when cutting the part, i was surprised to observe the saw blade is elliptical in shape! Only 5 or 6 teeth did all the cutting, because of the obviously out of round shape of the blade.

I can't image this is normal, or is it? I mean how hard is it to manufacture a round saw blade??
Moderator - Grand Scale Forum

Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

Ahaha, Retirement: the good life - drifting endlessly on a Sea of projects....
oldvan
Posts: 553
Joined: Mon May 05, 2008 6:46 pm
Location: Western NY USA

Re: Safe use of a slitting saw.

Post by oldvan »

Glenn,

I think you got a bum deal. The slitting saws I have are old ones I picked up at a sale, and they seem to cut on all the teeth. Is your arbor straight?
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Safe use of a slitting saw.

Post by Harold_V »

oldvan wrote: Is your arbor straight?
A valid question, and certainly the possible cause of run-put, but the arbor may also be straight and not concentric. If it's bent, the saw blade will wobble sideways. If it's a concentricity problem in relation to the register, it may not be evident.

Assuming the blade is running true side to side, remove the blade and place the tip of a DTI on the register. If it runs true, the blades are not properly ground. They'll still work adequately, but you'll enjoy a limited lifespan because the few teeth that make contact will do all the work.

Remember that a saw blade has a lot of teeth, each one of which should be making a chip (assuming full contact). Too slow on the feed, depending on the duration of contact of the tooth with the part, may lead to premature wear. An idling tooth tends to wear, where a tooth producing a chip prolongs sharpness. Balance the thin blade and depth of cut with the feed rate. No hard, fast rules, it's more or less a "feel" you get when you start the cut. Cuts with great contact require a slow feed, so the gullet doesn't get overloaded with chips before leaving the cut.

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
revrnd
Posts: 366
Joined: Sun Dec 18, 2011 10:38 pm
Location: Ontario, Canada

Re: Safe use of a slitting saw.

Post by revrnd »

The machining of my 2 slits went well w/ a 3" saw. I used tapping fluid as a lubricant. "Timidly" I used .030" cuts. For the RPM, I just used the (CS x 4)/D.
OlderNewbie wrote:I just forged ahead and started to slit things, using what I thought was an appropriate SFPM and a feed that sounded OK, with plenty of brushed-on cutting oil (steel) or WD-40 (Aluminum). When things didn't sound as though I was getting a clean cut, as in 1018, I backed out and re-ran the already-slitted section before continuing. I did learn to back off some speed from normal SFPM, but not by breaking or dulling anything...just because I didn't like how it sounded. This thread has been helpful for me, helping affirm that I was doing more or less the right things, even if by accident. So my message is a bit different. Use some caution, but don't overthink this. Using a slitting saw really doesn't seem to be that hard.

John
Is WD-40 a suitable lubricant for aluminum? We always used alcohol while drilling.
User avatar
BadDog
Posts: 5131
Joined: Wed May 17, 2006 8:21 pm
Location: Phoenix, AZ

Re: Safe use of a slitting saw.

Post by BadDog »

WD40 is a common and inexpensive fluid that works well for aluminum machining, and so is commonly used in the home shop (where it also has other uses). It also isn't as problematic as alcohol would be collecting on the machine (and under the vise).
Russ
Master Floor Sweeper
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Safe use of a slitting saw.

Post by Harold_V »

What Russ said. Besides, at least for me, it smells much better (to me, at least) than kerosene, which is the recommended fluid for aluminum.

I've never tried alcohol, although it may be quite good for machining aluminum. Dunno! I do know the fire hazard would be of concern, though. Besides, that's a waste of good whisky! (Just kidding, of course!) I expect it is quite good for cooling, considering its rapid evaporation.

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
revrnd
Posts: 366
Joined: Sun Dec 18, 2011 10:38 pm
Location: Ontario, Canada

Re: Safe use of a slitting saw.

Post by revrnd »

Harold_V wrote:What Russ said. Besides, at least for me, it smells much better (to me, at least) than kerosene, which is the recommended fluid for aluminum.

I've never tried alcohol, although it may be quite good for machining aluminum. Dunno! I do know the fire hazard would be of concern, though. Besides, that's a waste of good whisky! (Just kidding, of course!) I expect it is quite good for cooling, considering its rapid evaporation.

Harold
Harold, I've never used alcohol during machining alum' @ work, just drilling holes in fixture plates. Most of our work in the m/c shop was steel (progressive die sections). For tapping alum' Anchorlube was what was supplied. http://www.anchorlube.com/

I don't recall what we used for tapping steel. In the early 80s the tapping fluid that I was introduced to when I started my apprenticeship (a stinky dark brown fluid) was removed from use. Supposedly a carcinogen, not sure if the directive was corporate or governmental.

I don't ever recall seeing WD-40 in our plants. What was used in our shops was tightly controlled. If there wasn't a MSDS for a particular product, it wasn't allowed.
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Safe use of a slitting saw.

Post by Harold_V »

revrnd wrote:I don't ever recall seeing WD-40 in our plants. What was used in our shops was tightly controlled. If there wasn't a MSDS for a particular product, it wasn't allowed.
Now I understand.
Yeah, you're not likely to see WD-40 used, as it isn't a recognized cutting oil. That doesn't prevent its use as such, and it does a great job. If you have it at your disposal, and you aren't fond of the smell of kerosene, give it a go.

I have used all manner of lubricants for aluminum, one of which is nothing more than slightly dirty Stoddard solvent. The traces of oil that are included lubricate the cutting tool, preventing chip welding, which is really the main purpose. It's obvious if the lubricant of choice works, or not, the moment it's applied. I do NOT use it for tapping, however.

I tend to use commercial lubricants for tapping. It's all too easy to break a tap, usually on the last hole, so I try to eliminate potential problems.. Tapping, as most of us know, is a demanding operation, so anything that can be done to lower friction is wise. Proper lubricants do just that, which is why I miss the old formulation of ferrous tapping fluids. The removal of 1,1,1-Trichloroethane from tapping fluids for steel and alloys is still a sore spot with me, in spite of the potential hazards.

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
revrnd
Posts: 366
Joined: Sun Dec 18, 2011 10:38 pm
Location: Ontario, Canada

Re: Safe use of a slitting saw.

Post by revrnd »

Harold_V wrote:I tend to use commercial lubricants for tapping. It's all too easy to break a tap, usually on the last hole, so I try to eliminate potential problems.. Tapping, as most of us know, is a demanding operation, so anything that can be done to lower friction is wise. Proper lubricants do just that, which is why I miss the old formulation of ferrous tapping fluids. The removal of 1,1,1-Trichloroethane from tapping fluids for steel and alloys is still a sore spot with me, in spite of the potential hazards.
Harold
Harold is that what would've made up the tapping fluid I was speaking of? A lot of us that had used the "stinky stuff" bemoaned the fact that we never came across a tapping fluid that equalled its qualities.

Kind of OT, but I do recall my father saying that carbon tetrachloride (the cleaner) was banned from the plant prior to the 80s.
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Safe use of a slitting saw.

Post by Harold_V »

revrnd wrote:Harold is that what would've made up the tapping fluid I was speaking of? A lot of us that had used the "stinky stuff" bemoaned the fact that we never came across a tapping fluid that equalled its qualities.
If the fluid you spoke of was for use with aluminum, then, no, that wouldn't be the 1,1,1-trichlor. It was used for ferrous alloys and stainless, but not recommended for aluminum. For that, they had a different formulation, which may well be the same today.

If memory serves, a fresh can of the fluid intended for steel had the smell of cinnamon. Needless to say, that was added to make the fragrance more acceptable. Personally, I liked the smell, in spite of the fact that it most likely was not healthy.
Kind of OT, but I do recall my father saying that carbon tetrachloride (the cleaner) was banned from the plant prior to the 80s.
Yep! I expect that it was not too long afterwards that trichlor was also banned, at least by the EPA, here in the States. They have a similar smell, so it's easy to get them confused if you're not intimately familiar with both of them. Carbon tet, along with other solvents were banned due to the hazards they present. Vapor cleaners, for example, fell out of favor, but they did a beautiful job of cleaning.

Trichlor used to be added to the coolant in machine tools (along with oil, never straight). What it did for machining was hard to understand, being a very thin fluid, which you likely recall from the old, smelly tapping solution(s).

I used to use trichlor for washing electrical connectors after machining the bodies (for Univac). Just a few seconds after getting it on my hands, I could taste it in my mouth. I fully expect that that was not good for the body, and is likely one of the reasons it has been chiefly removed from the market. I used to buy it by the five gallon pail, and for not much money. Today, the price is prohibitive. What better way to get something off the market than to price it out of reach?

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
revrnd
Posts: 366
Joined: Sun Dec 18, 2011 10:38 pm
Location: Ontario, Canada

Re: Safe use of a slitting saw.

Post by revrnd »

Harold_V wrote: If the fluid you spoke of was for use with aluminum, then, no, that wouldn't be the 1,1,1-trichlor. It was used for ferrous alloys and stainless, but not recommended for aluminum. For that, they had a different formulation, which may well be the same today.

If memory serves, a fresh can of the fluid intended for steel had the smell of cinnamon. Needless to say, that was added to make the fragrance more acceptable. Personally, I liked the smell, in spite of the fact that it most likely was not healthy.

Harold
I should've been more specific, the stinky stuff was for steel, Anchorlube for alum'.
Post Reply