MadModder

The Shop => Tools => Topic started by: Chazz on July 28, 2011, 10:19:58 AM

Title: Cutting down a lathe tool holder?
Post by: Chazz on July 28, 2011, 10:19:58 AM: As most if you know an AXA QCTP will hold up to a .5" x .5" shank tool. Has anyone ever taken a .63" x .63" or even a .75" x .75" shank tool and milled the bottom and sides to fit the AXA tool holder?

The reason I ask is, I got an import .5" x .5" RNMG tool holder and the neck is so skinny it looks like it will snap just looking at it. I'm pretty sure the holder will deflect if I try to take any sort of serious cut? :scratch: So I checked Kennametal and Sanvik and their smallest Round insert tool holders they have start at .63" x .63", but look a lot more robust.

Any thoughts? Thanks,
Chazz
Title: Re: Cutting down a lathe tool holder?
Post by: DaveH on July 28, 2011, 10:49:24 AM: Chazz,

These insert tool tip holders can be quite hard.
I have done a couple, (only off the bottom) I attack it with an angle grinder, then finish on the mill with an insert tip cutter.

Subtle eh :doh:

DaveH
Title: Re: Cutting down a lathe tool holder?
Post by: JimM on July 28, 2011, 11:46:06 AM: I've also done this to a few of mine (the big ones are cheap on Ebay !)

The toolholder material is bloody hard, went through 3 end mills before I gave up. In the end, best method I've found is taking off the bulk with a hacksaw/bandsaw, then finishing with a file.

Jim
Title: Re: Cutting down a lathe tool holder?
Post by: bry1975 on July 28, 2011, 01:20:14 PM: As DaveH mentioned wouldn't a very thin metal cutting disk work a treat with a decent angle grinder?

Bry
Title: Re: Cutting down a lathe tool holder?
Post by: websterz on July 28, 2011, 05:31:08 PM: Quote from: bry1975 on July 28, 2011, 01:20:14 PM
As DaveH mentioned wouldn't a very thin metal cutting disk work a treat with a decent angle grinder?

Bry

Yes it will, just be careful of thin cut-off discs on angle grinders...they tend to flex...and explode.
Title: Re: Cutting down a lathe tool holder?
Post by: doubleboost on July 28, 2011, 05:49:58 PM: http://madmodder.net/index.php?topic=4102.msg61126#msg61126
Title: Re: Cutting down a lathe tool holder?
Post by: doubleboost on July 28, 2011, 05:52:55 PM: Sorry i made a propper mess of that i was trying to copy a link ti some tool holders i modified
Perhaps one of the mods would sort it for me :thumbup:
John

edit
I have sorted it for you John
Don
Title: Re: Cutting down a lathe tool holder?
Post by: John Hill on July 28, 2011, 08:28:50 PM: I needed to cut down a few tool holders, the first one was quite hard but a drill would make some impression so I drilled a number of divots all to the same depth (as near as I could manage) then used an angle grinder to take it down to the bottom of the divots. I was suprised how 'true' the sureface was doing it that way.

Then I got smart and realised the tool holders could be held in the lathe tool post, but on their side, then I chopped the next couple of holders with a fly cutter I made, but it was really hard on the HSS tools in the fly cutter.
Title: Re: Cutting down a lathe tool holder?
Post by: bry1975 on July 28, 2011, 10:24:19 PM: Anyone have access to a Plasma cutter?
Title: Re: Cutting down a lathe tool holder?
Post by: Erik Boring Head on July 30, 2011, 03:50:42 PM: I've cut a sandvik holder from 16mm to 14mm with a home made flycutter with an insert tip, on my mill

that went well :D

Erik
Title: Re: Cutting down a lathe tool holder?
Post by: AdeV on July 30, 2011, 03:57:54 PM: Quote from: bry1975 on July 28, 2011, 10:24:19 PM
Anyone have access to a Plasma cutter?

I do - it's a bit of a beast, but it's a bloody good cutter.
Title: Re: Cutting down a lathe tool holder?
Post by: nickle on August 02, 2011, 06:19:00 PM: I bought myself a set of insert tools for my mini lathe that were a bit high. I mounted one in the four jaw chuck and "faced" the bottom off it with a hss tool. once I had the first one done I was able to use it to face the back of the others. The nice thing about it was that I was able to bring the tool height to bang on center for all but one of the holders. no packing required, just straight in the toolpost.

Hope this helps.
Title: Re: Cutting down a lathe tool holder?
Post by: kvom on August 03, 2011, 08:39:14 AM: You can make an attachment for the toolpost to hold a larger shank. Might be easier than modifying the holder. I've done this for some boring bars. Straight piece of steel with a channel to hold the holder, and cut down on the opposite side to fit an AXA holder.
Title: Re: Cutting down a lathe tool holder?
Post by: Chazz on August 03, 2011, 10:10:02 AM: Thanks Lads, I guess NOW I'll have to get 2 tool holders :drool: One to Mill down and one to face down on the lathe :headbang: and see what happens. I don't think I'll aneal the holders prior to 'working' and then re-harden as I have nill experience in heat treating yet, and, I'd be concerned with twisting or distorting the tool holder. (They are not cheap).

Cheers,
Chazz
Title: Re: Cutting down a lathe tool holder?
Post by: Jonny on August 03, 2011, 07:56:11 PM: Wont be much bother those holders arent very hard just use good cutters.
The knurling one is hardened, not recommended.

Turned plenty of decent tool holders down in 4 jaw chuck, Kennametal Top notch, Sandvik, etc when i had a toy lathe. Just need decent cutters.
Grinding takes too long.
Title: Re: Cutting down a lathe tool holder?
Post by: DaveH on August 03, 2011, 08:11:42 PM: Quote from: Jonny on August 03, 2011, 07:56:11 PM
Grinding takes too long.

Not the way I use an angle grinder it don't :lol: :lol: :lol: :lol: :lol: :lol:

DaveH
Title: Re: Cutting down a lathe tool holder?
Post by: doubleboost on August 04, 2011, 06:12:14 PM: Quote from: DaveH on August 03, 2011, 08:11:42 PM
Quote from: Jonny on August 03, 2011, 07:56:11 PM
Grinding takes too long.

Not the way I use an angle grinder it don't :lol: :lol: :lol: :lol: :lol: :lol:

DaveH
I can use a angle grinder to within 25 thou :bugeye: :bugeye:(on a good day)
Trouble is the heat can make things go very hard :( :( :(
John