Mounting Chinese cutters on American arbor.

[BROCKWOOD]

I did not want or intend to buy the Chinese cutters. But at $99 for a set of 8, it moves me forward. I did buy a 7/8" arbor a while back. How do you mount these cutters with Bore: 22mm - 0.866142in (7/8 = 0.875)? Granted my NMTB 50 7/8" arbor needs a key slot & spacers, I'd rather not cut it down to 22mm. Are you all increasing the I.D. of the cutters? What is the general best way here?

 

[ddickey]

Probably buy the correct size arbor, that would be the best way.
I have turned down milling arbors before to fit the id of a face mill.
They're quite hard but doable. I mounted a brazed carbide lathe tool in the mill vise and lowered the quill.

 

[BROCKWOOD]

Thanks DDickey. An NMTB50 x 22mm arbor should be as fun to find as all the other milling stuff I've bought. Choose Van Norman as your mill of choice ............................ You'll see my humor & resolve!

 

[ddickey]

I looked around a little. Can't find anything. Ouch

 

[BROCKWOOD]

ddickey, I may just half n half the 7/8" arbor I have. It's 11" of shaft. So, I could undersize the 1st 5+" to 22mm. Then key each portion according shaft size & make collars specific to each portion. A fun little project that will also involve slotting internal keys. Something else to figure / learn!

 

[Moper361]

I ended up in similar situation .In the end i brought a cheap 22mm shell mill arbor and made up a end cap and a backing ring seems to do tbe job fine for what im doing. However finding that bt50 in this type arbor not so easy

 

[BROCKWOOD]

Thanks Moper. Looking good! I have another 7/8" arbor for the horizontal coming - only it has the key & spacers. So, I'll convert my current arbor that needs a key & spacers to 22mm. Both have a 12" usable bar length. I have a stub arbor similar to yours, but it is a 1" shaft.

 

[BROCKWOOD]

Surprise! My $99 Dp14 Chinese gear cutters made it all the way from China to me (was starting to think that was a $100 lesson in what not to do). Well - that might still become the case, but at least I have the cutters to answer that question! So, 1st pics & then the NMTB 50 arbor is next on the lathe. As is, the cutter won't clear the threads for the end nut.

 

[NortonDommi]

What do they measure at? Usually cutters are fractionally O/S on the bore. Even if bang on 22 mm that is under 0.0045" tight. If you have another arbor coming I think your idea of making what you have 22 mm is a good one as you are bound to pick up Metric and Imperial cutters as you go.
I bought some Russian gear cutters from before Glasnost and they were 3/4" exactly. Ended up making an arbor as I couldn't buy one. Had to make a toolpost grinder to do it too so was heaps of fun all round.

 

[BROCKWOOD]

The arbor shaft is spot on 0.875" & cutter inside diameter is 0.869+". Key is 0.242" wide on cutter. The arbor is actually 10" - whereas my newest addition 7/8" arbor is 12". The new to me has the keyway, key & spacers. I am lucky to have this arbor that needs a keyway & spacers to convert to metric! I'm not set up to do toolpost grinding yet. I'll just chuck the arbor up & sand it down to size for a day. Cutting the keyway & making spacers will be much more fun!



Bottom left corner is the arbor set for conversion. It looks skinny without any spacers on it.

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