Making tools from Stainless?

According to the web, 416 stainless has less than 0.15% Carbon in it, so it shouldn't harden very well (close to 12L14 except for the chromium). If it had 0.40% - 0.80% you could harden it and it'd be tough as a punch. You'll be fine as long as nothing snags your arbor/saw.

Bruce
 
BGHansen said:
According to the web, 416 stainless has less than 0.15% Carbon in it, so it shouldn't harden very well (close to 12L14 except for the chromium). If it had 0.40% - 0.80% you could harden it and it'd be tough as a punch. You'll be fine as long as nothing snags your arbor/saw.
Bruce
Click to expand...
That is interesting! I didn't realize it had so little carbon. I have been hardening 416 in the past making bolsters for knives and it does seem to get harder. Much less prone to scratching when hardened and the file skates across it. I never thought to measure how hard it actually got after treatment though since it was a decorative part and not the blade.

I thought about heat treating these arbors but am worried that the part may warp slightly with the heat and require grinding back to true. I may give it a try with one of my original parts though that I don't intend to use and just see what happens.
Thanks!
Stuart
 
Thanks for the datasheets Tony. Looks like crucible specs it at minimum RC35 when heat treated so probably worth going for it- time to crank up the HT oven!
 
You're most welcome. I like to refer to those whenever I start a project with a new material. Lots of hidden information can be gleaned from studying the datasheets from the people who make the stuff. Of course, some of it is sales pitch, but the actual specifications are generally not inflated or embellished and you can depend on them.
 
StuNY said:
I have started making my own r8 arbor's for slitting saws etc and for the first couple grabbed a bar of 416 stainless that was the right diameter. They cut very easily, gave me a nice finish and work very well in the mill. Any reason I shouldn't be using stainless for these (other than cost)? I like the idea of not having to worry about rust etc, and they sure are purty! I am not planning to harden them so wonder if I am fine with it or should be using regular carbon steel/tool steel. They are 5-6 inches long and at widest point 1.25" diameter, turned between centers and I am using carbide inserts in toolholder.
Thanks!
Stuart
Click to expand...

Great idea, now I know what to do with some old barrel stubs.
 
Before I heat treat my original R8 mandrel I thought I would use an indicator to see just how straight it was to see if it warps after HT. Since I turned it between centers and it seemed to cut well I had assumed it was pretty accurate- it didn't visibly wobble like my original Grizzly arbor did. Nope! Mounted in the spindle and snugged down it shows 0.004" of runout where the blade mounts! So then out of curiosity I did same with the one I finished last night using a straight shaft that fits in 7/8 collet. Runout was 0.0005". I always assumed that a direct R8 mandrel should be more accurate but guess I learned what you all already knew- collet is better!

Even at 0.0005" runout though, the slitting saw still makes that odd "cutting with a handful of teeth" throbbing sound. I am wondering if the slitting saw blade is not all that accurate. When I put an indicator on the blade from above at the full 3" diameter there was about 0.003" wobble as I spun it. The mandrel hub itself shows no measurable (by me!) wobble. I have another saw blade arriving today to check and see if consistent with above.
 
Almost every slitting saw I have ever seen has at least one tooth or more that is slightly bent. The saw cuts with an intermittent scratchy sound; this is normal. As long as the cut is clean, I don't worry about it.
 
StuNY said:
That is a relief Mike- thanks!
Click to expand...

Yup, you're welcome. If you don't mind, I'd like to offer some tips for using these saws:
  • These saws are intended to take a full depth cut from the start. Sneaking up on final depth just wears the blade and dulls them faster.
  • Proper cutting speed is the critical cutting parameter. I'm attaching a sheet from Martindale that will help. Speed is dependent on the material being cut; it will be much faster than you think.
  • Proper feed is almost as important. You want a positive feed; that is, you should feel a slight resistance to feed as you make a pass. Some folks use power feed but I find it better to feel the cut.
  • Most slitting saws have zero set so chip clearance is a major issue. Anything you can do to help clear the chips helps - air, a brush, and the coarsest saw you have that will do the job.
  • Heat is bad for a zero set blade. Using a lot of cutting fluid helps lube and cool the blade. I use a lot of paper towels under the blade to catch all the lubricant I apply. I also wear an apron to catch the oil that gets on me!
  • You should have the right number of teeth in the cut. The table I attached will give some valuable guidance. Having at least 3 teeth in the cut is a good rule of thumb. I use the coarsest saw I have for the job to clear chips but sometimes you only have blades with too many teeth. You can still use them but you have to feed slower.
  • Sometimes you need a slot width that is wider than the blades you have available. With zero set blades, you can stack em' if your holder will center the blades. This is why I like the Sierra American design; it allows me to stack several blades on top of each other while maintaining the concentricity of the stack. Of course, the blades have to be of the same diameter.
  • Use the smallest diameter blade that will do the job. This improves rigidity.
Hope this helps. And don't worry about that out of line tooth - the saw will cut fine.
 

Attachments

  • HelpfulHints13_16.pdf
    83.5 KB · Views: 26
You must log in or register to reply here.
Back
Top