Author Topic: Large diameter tube bending die .  (Read 4891 times)

Offline NeoTech

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Large diameter tube bending die .
« on: November 08, 2012, 06:13:42 PM »
So i have this idea of making a bending die.. buying a big chunk of 200x50mm thick steel plate is out of the question.. its so bloody expensive its ridicolous..

so i came up with this.. its made out of 50x50mm barstock. The dies are cut in blocks of 50x50x50 and then milled into an angle that divide the 360degress to 12 pieces. The blocks is then welded onto a 6mm disc, and a lid disc of 6mm..  for roll pins, 28mm OD tubes with 4mm wall is turned and welded into the places where the pins will go..

The whole assembly is then turned for the pipe diameter after assembly.



Am i totaly insane.. or is this feasable?
Machinery: Optimum D320x920, Optimum BF20L, Aciera F3. -- I have not failed. I've just found 10,000 ways that won't work. http://www.roughedge.se/blogg/

Offline BillTodd

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Re: Large diameter tube bending die .
« Reply #1 on: November 08, 2012, 07:10:10 PM »
My brother made a 8" former for a one & a bit inch tube, by laminating it out of plates -welding the plates together through holes in the sides (I turned the radius for him).

He fabricated another larger one using the inner half of bent sections of tube, by welding the quadrants to circular plates.

It is not too disimilar to what you are proposing, so yours should work if the tube has sufficient support

I'll post photos later

[edit]

In the attached picture you can see the holes in the face where a bead of weld holds the plates together.

 
« Last Edit: November 09, 2012, 08:27:33 AM by BillTodd »
Bill

Offline NeoTech

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Re: Large diameter tube bending die .
« Reply #2 on: November 09, 2012, 02:17:36 PM »
ah, nice.. that radius tool there looks a bit sketchy but it seems to have worked.. need to make me a radius turner as well . =)
Make a tool to make a tool so you can make the jigging tool to hold the actual work.. yeap.. many steps ;D
Machinery: Optimum D320x920, Optimum BF20L, Aciera F3. -- I have not failed. I've just found 10,000 ways that won't work. http://www.roughedge.se/blogg/

Offline BillTodd

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Re: Large diameter tube bending die .
« Reply #3 on: November 09, 2012, 02:37:08 PM »
The bottom part has a couple of ball races in a short spindle. The spindle is clamped into a Z section fabricated from 1/2" (13mm) plates.

It worked surprisingly well: (here it is at work on a smaller diameter former)

Bill

Offline NeoTech

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Re: Large diameter tube bending die .
« Reply #4 on: November 09, 2012, 05:26:32 PM »
Well if it aint broke, dont fix it.. that looked easy enought to realize in a short amount of time. =)
Machinery: Optimum D320x920, Optimum BF20L, Aciera F3. -- I have not failed. I've just found 10,000 ways that won't work. http://www.roughedge.se/blogg/