Slitting Saw Woes

Great news. I sharpened the ends of the teeth on the blade and gave it another go on a scrap collet I made (broken tap in base). It worked great and I used the same arbor as before, same cutting speed plus a little cutting fluid and the blade just chomped its way through the collet, with a full depth cut. I believe the problem I encountered before was due to the ends of the teeth being dull. It was uneventful (except for my cheering when I was done). Bonus is; the blade is still very sharp.
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:):):):):):):):):)
 
Did you just give it a touch on the periphery? That looks like a nice shop made grinding jig.
 
ericc said:
Did you just give it a touch on the periphery? That looks like a nice shop made grinding jig.
Click to expand...

Yup, just a faint touch is all it took and what a huge difference it made. The jig is not my idea. I got the plan from one of Harold Hall's books. It was simple to make and works great. I'm planning on making one of his grinding rests and that will make setup for this jig much easier but for this run I just rigged up something temporary. Fine tuning the blade setback from the grinding wheel was made with a small machinist hammer. This will be a simple process when I get the grinding rest done.

I'm not sure but the plan for this jig might be on his website. He does offer quite a few plans for free.
 
I got the impression that a lot of the problems had simple causes. Spinning too fast was one of them. Loading up the gaps was another. I tried running the air hose past the teeth as they came out of the cut, to clear out the chips, and a lot of my problems went away.
Cheers
Roger
 
The thing that has gone unsaid in this conversation is that collets are hardened, which makes them tough to cut from the start.
 
I've also had slitting problems while using my X2 Mini-Mill. Several posts in this thread discuss need for the proper rpm. It seems that my X2 doesn't have enough torque at the proper rpm. So I too have burnt up some HSS blades (from Little Machine Shop (LMS). My recent post "Mini-Mill - Ideas on Improving Low Speed Torque?" wonders what might be done to solve the problem. This can also be a problem when doing large diameter drilling and boring on the mini-mill.
The only reply so far (thanks cmantunes) is "Carbide slitting saws. You can safely multiply that SFPM by 3 or 4 (that's what I do). Drawback is the price of carbide vs HSS. I tend to buy carbide slitting saws directly from China to avoid breaking the bank." My brief search shows even the Chinese ones are $$$. Maybe someone can suggest a source?
 
I have not seen any "cheap" carbide slitting saw blades. Ebay is only the place where you may be able to find carbide for less, or Tormach TTS.
You can also call Martindale to see what they charge, but they have a minimum order. I did see a Robb Jack USA carbide saw blade on ebay for $50.00
 
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