2 types of BT35?

V

vegard

Aluminum

Joined

Jan 28, 2006

Location

San Diego, CA

• Nov 14, 2017

• #1

Hi,
I just put a kitamura MyCenter 1 in my garage, and I am trying to get it tooled up.

Looks like there are 2 types of BT35 with slightly different pull stud bores and the v-flange slightly different? I just learned this while trying to use my brand new holders...

I got 4 nikken sk10 collet chucks and a couple centaur ER16's that are the wrong type (looks like MAS BT35 vs regular BT35) These are brand new...

What gives here?? I guess there are machines out there that use this other spec of BT35?

Anyone know a source for ER chucks with the old BT35 to fit my kitamura? I am not even sure how to tell which one I am looking at online, as no one seems to differentiate the two specs, but so far 100% of what I have bought new has been wrong....

See here http://www.lyndexnikken.com/cp/303A/E189.pdf

Thanks

Vegard

 

V

vegard

Aluminum

Joined

Jan 28, 2006

Location

San Diego, CA

• Nov 14, 2017

• #2

Here's a dumb idea: It looks like the MAS BT35 could be machined into regular BT35. Hard turning maybe? It might cut through the case hardening though...

I would need to remove:
.063" from the flange and pull stud end
.0091 per side on the taper.
open the pull stud pilot ID by .020 or turn down the pull studs.

How bad an idea is this?

 

V

vegard

Aluminum

Joined

Jan 28, 2006

Location

San Diego, CA

• Nov 14, 2017

• #3

quick sketch with the v flange lined up:

 

M

mneuro

Cast Iron

Joined

Sep 15, 2014

Location

Denver

• Nov 14, 2017

• #4

Why do more work than you have to? If they are new, can you just return them? Command sells BT35 holders.

BT35 - Command Tooling Systems

 

V

vegard

Aluminum

Joined

Jan 28, 2006

Location

San Diego, CA

• Nov 14, 2017

• #5

Good call. Looks like command is the correct type. I am still stuck with the Sk10 chucks, so I may still cut those down.

 

mhajicek

Diamond

Joined

May 11, 2017

Location

Maple Grove, MN, USA

• Nov 14, 2017

• #6

I would shy away from recutting the taper unless maybe you have a really precise lathe to do it on. A tiny amount of error there will make a huge difference.

 

G

Garwood

Diamond

Joined

Oct 10, 2009

Location

Oregon

• Nov 14, 2017

• #7

I think BT35 is BT35. Maybe you got cat35?

I would not touch the taper on a lathe, but the flange can be cut by any heavy lathe. Toolholders are not that hard you just a stout lathe that will not notice the index slots.

The last one I turned down I took the entire flange off in one pass. It got me past the index slots so it wasn't an interrupted cut anymore. Like .400 DOC and .007/rev peeled it right off.

 

L

LKeithR

Stainless

Joined

Sep 1, 2011

Location

Langley, B.C.

• Nov 14, 2017

• #8

Good info on tapers here...

http://www.tools-n-gizmos.com/specs/Tapers.html

 

B

bassbrawls

Aluminum

Joined

Sep 19, 2006

Location

Florence, Oregon

• Nov 15, 2017

• #9

Are there part #'s on the holders? It almost looks like one is a standard BT35, and the other is a dual contact BT35... but I could be wrong. I wouldn't mess with re-machining the tapers and flanges as you might cause damage to your spindle.

 

G

guest

Guest

• Nov 16, 2017

• #10

It's strange. There is one on ebay that lists the toolholder as MAS BT 35. That Lyndex page sure had two different versions.

Kitamura MyCenter1 CNC Drilling Center | eBay

edit to add: OP should measure the drive keys on the spindle and see which one is correct. The difference is the width of the keys and the distance from the gage line to the v-groove. Those are tool changer accomodations.