Triac PC spindle taper

All info relating to the Denford Triac series of CNC milling machines

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Choco
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Joined: Sat 09 Jan , 2021 23:51 pm

Triac PC spindle taper

Post by Choco » Mon 03 Feb , 2025 15:46 pm

Hi, I'm trying to figure out what taper is inside my Triac. It's made in 1998. It is the Non ATC model. It came with the easy change tool holder. I think they came with either an R8 or BT30 taper for the manual change models ? Pics of the tools that came with it. It looks like BT30 ?
If it's BT30 it should be easier to convert to power draw bar ?
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Steve
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Re: Triac PC spindle taper

Post by Steve » Mon 03 Feb , 2025 21:39 pm

It’s a BT 30

Choco
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Joined: Sat 09 Jan , 2021 23:51 pm

Re: Triac PC spindle taper

Post by Choco » Tue 04 Feb , 2025 0:44 am

When denford released the triac versions, the ATC and the manual version. It says in the manual the ATC came with the BT30 and the manual iso30. Has the bt30 spindle the dog legs to stop the tool rotating? Or is the spindle the exact same between the bt30 and iso30 versions?

moray
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Re: Triac PC spindle taper

Post by moray » Tue 04 Feb , 2025 1:26 am

The difference between BT and ISO is primarily the top/small end of the taper, although I think there may be differences in the large end where BT tooling gets held by the toolchanger.
ISO has a parallel shanked section extending past the small end of the taper, whereas BT simply stops at the end of the taper.

Provided the drawbar is long enough (and the correct thread - some older tooling may have an imperial thread), either will work in a manual spindle.

IIRC only very early ATC Triacs had the drive dogs fitted.
I've never paid that much attention to non-ATC Triacs, but for the available spindle torque on a Triac, the dogs don't really do much. BT/ISO/DIN tapers are self-locking, so provided the drawbar is suitably tight enough, the toolholder shouldn't spin in the spindle.

I suspect the ATC and non-ATC spindles will be identical. It's just that the ISO tooling will help with drawbar installation, as it'll extend part way up in to the void where the ATC gripper mechanism would be.

Choco
Posts: 12
Joined: Sat 09 Jan , 2021 23:51 pm

Re: Triac PC spindle taper

Post by Choco » Tue 04 Feb , 2025 1:51 am

That's great info thank you. I'll be looking at converting it to a pneumatic draw bar at some stage. It's the gripper collet that grips the pull stud up I think will be the difficulty if denford don't still sell it.

Choco
Posts: 12
Joined: Sat 09 Jan , 2021 23:51 pm

Re: Triac PC spindle taper

Post by Choco » Tue 04 Feb , 2025 13:22 pm

Just got a quote for the power draw bar conversation. Eye watering is an understatement, 627 pounds :(
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