Hollowing

[Andy London]

I bought the Scorpion and Stinger set up and we (son & I) finally got around to putting it together today. I was a little suprised the tips do not come sharpened or angled but we followed the instructions.

I am assuming the goal is to get a burr much like a scraper, which I attempted to do but I can't feel a burr and the cut is not that great or perhaps I expect to much. Should one be able to get nice long shavings from the cutters much like a scraper? I can't get a burr to save my soul on the tear drop shaped unit, kind of fustrating.

I went to Don's site as the instructions with the unit are somewhat hard to read and I have done everything he states to do....any feedback will be appreciated.

I just put new wheels on from Oneway....I tried grinding them per the instructions which is 10 degrees and nothing, so I tried grinding them the same as I do our scrapers as he receive amazing results with them....still no good, tried a diamond stick, tried a white wheel then tried my belt sander, generally one of these works but I just can't get a burr on the steel for some reason.....

Thanks
Andy

[Gary Max]

I love it Andy---I thought is was the only person who used a belt sander on lathe tools.
Hope you have good luck figureing this out.

[Andy London]

I love it Andy---I thought is was the only person who used a belt sander on lathe tools.
Hope you have good luck figureing this out.
Actually, on the parting tool, I can get the best cutting edge from the belt sander....I am one of these whatever works.....maybe that's why I have no room for more tools as I already have too many :D

[Jim Becker]

The small cutters on hollowing tools should typically only be "sharpened" by honing the top once you have the shape. You do not need a burr and trying to raise one, especially with the grinder, will likely result in a "gone" cutter. Those things can be ground away very, very, very quickly. I use a diamond hone to keep mine sharp with a very occasional trip to the grinder to use the side of the wheel to dress the top slightly for a sharp edge. You can hold the cutter in the actual tool or in a cheap boring bar designed for metal working. (I got mine from Enco)

[Andy London]

Yjamls Kim, as you are probably aware, these cutters are round when you get them, you grind a flat spot then shape the front, much like a scraper, if I am understanding you, one uses a diamond stick on the flat part, this would be opposite to a scraper then...am I understanding you properly??

[Jim Becker]

Any of the cutters I've ever seen, bought and used already had the flat spot on the top....and only required minor and occasional reshaping at the grinder (with a very, very light touch) and then kept keen with a diamond stone/hone on the top, flat surface.
----
Edit:

I looked at the pictures of the cutters that Don Pencil is supplying and they appear to be "roll your own" relative to profile and are simply 3/16" HHS drill rod. You might consider picking up some of the harder cobalt steel cutters available for the Stewart or Jamison systems. They will slip into a 3/16" hole and since they are basically square in area, are very easy make slip-proof with the allen screw. They usually come pre-profiled, too. I've also bought this material in bulk from Enco.

[Andy London]

Thanks Jim!, I'll order some cutters and see how it goes. I was a little suprised at the cutters with this system, you are correct in that they are just round HSS you form yourself, I expected a little more for four hundred bucks....CDN

[Jim Becker]

Try Model #383-5212 at:

http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=383-5212&PMPXNO=940311 (http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=383-5212&PMPXNO=940311)

3/16" cobalt steel. Just grind a radius on one end with about a 30º bevel and you have your cutter. It will last a whole lot longer than the HHS round drill rod you were supplied. You can cut the blanks in half to make them easier to use...grind your end profiles first so you have more to hold onto with your tool or vice grips or whatever you use to keep your fingers away from the wheel!

J