Introduction: DIY Mandrel Bender

Picture of DIY Mandrel Bender


Step 1: Tube Holding Blocks

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Step 2: Die

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I got a gear weld on blank and cut the profile of the 5/8 tube in it , using a 5/8 ball end cutter.

Step 3:

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Step 4: Making a Cut Out for Clamp

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Step 5:

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Step 6:

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Step 7: Clamp Placement

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Placed clamp to see how it fits now it's ready for welding

Step 8: Prep for Welding

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Step 9: Welded

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I tig welded the clamp to the die using stainless steel filler rod

Step 10:

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Step 11: Back in Mill

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I put the welded parts back into the milling machine indicated it straight ready for the cut with the ball nose cutter

Step 12: Blended in Ball Nose Cut

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Step 13: Machine Clamp

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I screwed in the opposite side of the clamp to the die in the vice so I can hold it ,so I can machine it with the ball nose cutter

Step 14: Finished Machining Clamps and Die

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Step 15: Clamp

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I tested the clamp on a piece of .625" inch round tube

Step 16: Mandrel

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To make the mandrel I'm using a piece of M8 metric threaded rod , I put two stainless screws on the end of it getting them ready to weld together

Step 17: Mandrel

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After welding together I forged it with a hammer to harden it.

Step 18: Grinding Mandrel to Size

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Step 19: Grinding Mandrel

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To bring it to the right size and shape I put the end of the threaded rod into a drill then I sanded it on a disc sander,

Step 20:

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Step 21: Finished

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Step 22:

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Step 23:

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Step 24: Checking Fit of Mandrel

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Step 25: Tube Guide

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I machined a tube guide from brass

Step 26: Tube Guide

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I drilled holes to mount onto a plate

Step 27: Tube Guide Support

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Step 28: All Together

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Step 29: Crank Handle

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Step 30: Bottom of Crank Handle

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I made a cut out for the tube clamp and a bored hole that locates the die

Step 31: Ready to Test

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Step 32:

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Step 33:

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Step 34: Worked Perfectly

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Step 35: Time to Make Some Parts

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Takdashark (author)2017-02-18

First off, amazing work! Ia little confused how the threaded rod mandre functions. I feel like I'm missing something. The rod would and get stuck in the part of draw through with it, so there's definitely something I missed or it magic!

redchapman (author)2017-01-19

This is really cool, thanks for sharing! Can I borrow that ball nose cutter? Haha.

I was searching around online and found these guys:

Would you recommend them as well?

rionela (author)2015-11-10

very good i was thinkung to make the die mobile or somthing like this ones

ARJOON (author)2015-10-20

impressive work but that tig weld :S

romulobc48 (author)2015-06-21

vincent7520 (author)2014-03-16

Only on Instructables can you find people crazy enough to make a bender that I'm sure works even better than the manufactured ones !!!…

Thank you.

This is perfect.

Again thanks for posting.

NovelUserName (author)2014-01-17

Very Impressive how well that works!

About This Instructable




Bio: I'm an inventor , machinist , welder .
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