Cat40 toolholder hardness

All,

So I have to make a Cat40 Renshaw probe holder. I have a couple of damaged holders ( the holder side, NOT the taper side) So I thought I could cut off the bad end, face it off and tap the required holes in the end.

So I learned the fast way that holders are hardened. Of course I already knew that, just forgot in the excitement of making a tool. So how hard are tool holders? And I get to experience tapping hardened steel.

The Renishaw book describes drilling & tapping the holder, so how does everyone else do this?

And while you are at it, please see my other thread about interfacing to a Yasnac MX2 control. Please.

ca

Reply to
clay
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Typically work hardening materials with tough skin usually they soften up somewhat once you are into them by a hundred or so deep. Most of our hacked up kennametal stuff I traded with MR Gadget to get he needed mods done and boeing wouldn't give him shop time.

Anyw I would tap drill oversize in your situation its not like the treads are under a lot of stress 50 percent should be fine use a hand tap they have very gradual taper and also a good EP lube.

Sorry pretty sure yasnac has been outlawed in my area.

Reply to
over a barrel

Oh and you can stuff a lathe tool in a mill vice and spin it in your mill spindle orks great for modifying holders otherwise oftentimes a bitch to get em accurately / securely up chucked.

Reply to
over a barrel

The lathe bit in a vice trick was what I had planned. Until I ran into the hardening. So I will try attacking it with a grinder, see if it is actually case hardened. thanks.

ca

Reply to
clay

I think you will find they are an alloy steel hardened to around 50/60 RC

Reply to
tpow

Just adhesive bond the thing ..... you're not cutting metal with the tool.

Reply to
john

Velcro....greatly enhances crash survivability...

Reply to
over a barrel

Are we men or mice here? Sheeze.

They're only case hardened 8620 steel. Mill bore and thread mill. If you don't want to spend the money on a thread mill (Harvey Tool, TIALN coated single form thread mills ~$75 USD give or take), c-bore / spot face through the case and drill and tap using conventional methods.

Reply to
Black Dragon

you can get these holders with soft ends for only a few bucks..........don't know what op is f'in about for.

Reply to
tpow

Speaking of thread mills these guys have good pricing. The one time I used them they had the thread mill in stock and shipped quick.

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Have also used this outfit with good results:

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Best, Steve

Regards, Steve Saling aka The Garlic Dude © Gilroy, CA The Garlic Capital of The World

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Reply to
Garlicdude

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