Repurposing a Torx Bit as a Broach.

I've been working on the brake set-up for my BadAst Astro Van build. This is a bracket I developed to hold the Wilwood Prop Valve I will be using.
http://images46.fotki.com/v1637/phot...MVC020F-vi.jpg
With the valve bolted on. Clear access to both of the outlets on the bottom of the valve and it's not going anywhere. Once the lines are made and bolted in it will be pretty solid.
http://images51.fotki.com/v1638/phot...MVC021F-vi.jpg

I ran into a bit of an issue with the prop valve placement. It is too low. The outlet for the front brake line I need to plug is to close to the bracket underneath it. I didn't think it would be a problem finding a low profile inverted flare plug to fill the hole but I have found nothing that will work. The regular plugs are to tall and I do not want to remake the bracket OR the hardlines, so.... I will make a low profile plug.
I puttered around in the shop the other night trying to figure out how to tighten the plug and came up with this. I bored a .173 diameter hole in a test piece of aluminum.
http://images41.fotki.com/v1634/phot...MVC001F-vi.jpg
Then I used a short Torx bit to "broach" a hole for the driver. I started it with a few taps from a hammer to make sure it was straight then just pressed it into the test piece with the 4" vise.
http://images45.fotki.com/v1636/phot...MVC005F-vi.jpg

Continued in next post.
Mark

This worked great! I have some 3/8-24 threaded brass rod coming from McMaster Carr today. Hopefully the technique will work as well on the brass.
http://images61.fotki.com/v1635/phot...MVC011F-vi.jpg
Making the inverted flare side is easy. A 3/16 drill and 90degree c'sink work perfect for that. Getting the "driver" side done will be the challenge.

I got the threaded rod and made a couple of plugs tonight. Went as easy as I was hoping. The Torx driver pushed in just as easy as it did with the aluminum test piece. I'm happy.
I got a foot of the 3/8-24 rod and used about half of this piece I cut off...
http://images54.fotki.com/v1642/phot...MVC002F-vi.jpg
Dilled a pilot hole and ran a 90 degree chamfering tool into the drilled hole to make the bevel.
http://images51.fotki.com/v1638/phot...MVC005F-vi.jpg
The beveled hole.
http://images41.fotki.com/v1634/phot...MVC009F-vi.jpg

For the broaching job, I drilled the hole out to .173 dia. That is the one I used in the aluminum piece.
http://images46.fotki.com/v1637/phot...MVC010F-vi.jpg
I ran the fitting into a 3/8-24 nut so I could get the "broach" tapped in straight.
http://images45.fotki.com/v1636/phot...MVC011F-vi.jpg
Just a couple of light taps with hammer got the broach started.
http://images46.fotki.com/v1637/phot...MVC012F-vi.jpg
I then clamped the assembly into the vise and pressed away...
http://images59.fotki.com/v1640/phot...MVC013F-vi.jpg
Continued in next post.

Didn't take much to do the job.
http://images52.fotki.com/v1639/phot...MVC014F-vi.jpg
I ran one into the prop valve.
http://images52.fotki.com/v1639/phot...MVC016F-vi.jpg
And checked the clearance. We are good to go.
http://images52.fotki.com/v1639/phot...MVC017F-vi.jpg

I made a couple of them while I was doing it. Now that I've made one the whole process only takes about 10 minutes. :)
http://images54.fotki.com/v1642/phot...MVC018F-vi.jpg
Now, on to bigger and better things!
Mark

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Thanks astroracer! We've added your Broach to our Metalworking category,
as well as to your builder page: astroracer's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-broach"> <img src="/uploads/163381/homemade-broach.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-broach">Broach</a> <span> by <a href="http://www.homemadetools.net/builder/astroracer_2">astroracer</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/broach'>broach</a> </div> </div> </div> </div>
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Very well done! :-)

Thank You Sir! I made a few more yesterday. A bit shorter then the previous attempts. They give me plenty of clearance now with no worries.
https://images45.fotki.com/v1636/pho...MVC005F-vi.jpg

I don't know why these aren't available off the shelf... Not only do they provide for clearance I need but I think they look 100% better then those tall plugs do. My plug is on the right. :)
https://images34.fotki.com/v1633/pho...MVC006F-vi.jpg
Mark

Quote:

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Originally Posted by astroracer

Didn't take much to do the job.
http://images52.fotki.com/v1639/phot...MVC014F-vi.jpg
I ran one into the prop valve.
http://images52.fotki.com/v1639/phot...MVC016F-vi.jpg
And checked the clearance. We are good to go.
http://images52.fotki.com/v1639/phot...MVC017F-vi.jpg

I made a couple of them while I was doing it. Now that I've made one the whole process only takes about 10 minutes. :)
http://images54.fotki.com/v1642/phot...MVC018F-vi.jpg
Now, on to bigger and better things!
Mark

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Lovely = got the same valve; had similar issues - I salute your solution!

I feel honored to receive your praise in your 1st post. Thank You.
Mark

Hi
If you take a sherical diamond stone tool mounted on 1/8th shank you can use a dremmel to dish out the face of your already hardened Torx etc bits and then they will cut like the grape ape...

Thanks for posting. This was a great idea and will be using.

Nice Work. Your broach could have made a little better cut if you had simply ground the bottom of your Torx bit flat. But if it works, I'm just being picky. Nice seat of the pants engineering.

Thanks for this one - nice out of the box thinking!

Regards,
Ruaidhrí

Thanks guys! I thought about grinding the bit before I did the try out but, it worked just fine as it was so I just skipped that step. If I was pressing this into something less malleable then brass or aluminum a convex grind would probably be beneficial. These materials didn't need it.
Mark

Good great work. I think Tony Foale posted this technique as well. Kudos to both of you for a good solution. Grest pics too Astro.
Bob

Quote:

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Originally Posted by astroracer

Thanks guys! I thought about grinding the bit before I did the try out but, it worked just fine as it was so I just skipped that step. If I was pressing this into something less malleable then brass or aluminum a convex grind would probably be beneficial. These materials didn't need it.
Mark

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You're pretty much cold forging the Torx shape into the brass. Good and hard. But seems like a challenge to remove the tool after doing so. Secret?
Cupping the face converts it to actually cutting the shape. i.e. not as hard, easier to form the shape, and maybe easier to remove the tool after forming.

Good stuff

Quote:

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Originally Posted by jimirwin

You're pretty much cold forging the Torx shape into the brass. Good and hard. But seems like a challenge to remove the tool after doing so. Secret?
Cupping the face converts it to actually cutting the shape. i.e. not as hard, easier to form the shape, and maybe easier to remove the tool after forming.

Good stuff

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Had no problem at all removing the bit after forming. Wiggled it a bit with my fingers and it came right out. Really, this worked as easily as I documented it. I don't think it would have made any difference in the result if I had convex ground the tip prior to the forming. It's easy enough to do, try it and let us know what you think. :)
Mark

I cut them flat, but a dish would make the ape's banana eazyer to peal. Ive been using torques bit for almost 30 years for stuff like this.especialy on engine blocks with square head pipeplugs(steel) that are stuck and round out the holes with the proper remover's.just get the right sizz torques bit a few wacks and out they come. being a performance engine machinest/builder, Ive done a lot of those. some people like applying a lot of heat Ive never been a fan of flame on cast iron.for some reason the amuminum engine blocks dont have this issue....go figure. ( usualy replace all pipe plugs with brass on all engines. ezpecialy aluminum engines...witch in many cases have aluminum plugs or the kits sold are aluminum plugs....not good, dont even think of it.it's way to eazy to gauld aluminum with aluminum. I supose if weight was a issue a titanium pipe plug would work.

I have to see this Astro van! I love Astro vans!

Awesome use of the old noodle!! You might have just created your own "niche" market.
Great job and thanks for sharing.

THOSE TORX QALSO MAKE AWESOME BROKEN STUD REMOVERS!!! DRILL WACK IT IN AND REMOVE STUDS!!! IVE BEEN DOING IT FOR YEARS WITH THOSE.

Nice solution.
Could one not use grub screws (they come in 3/8 x 3/8 24 and are available off the shelf) with allen socket, they come in both stainless and HT or do they need to be brass.

"I don't know why these aren't available off the shelf... Not only do they provide for clearance I need but I think they look 100% better then those tall plugs do. My plug is on the right."

Quote:

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Originally Posted by Tonyg

Nice solution.
Could one not use grub screws (they come in 3/8 x 3/8 24 and are available off the shelf) with allen socket, they come in both stainless and HT or do they need to be brass.

"I don't know why these aren't available off the shelf... Not only do they provide for clearance I need but I think they look 100% better then those tall plugs do. My plug is on the right."

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Grub screws are just set screws. They don't have the correct seat to seal the flare on the inside of the fitting. You will see I had to make that seat as well in post 2. Brass is also a better material as it will deform a bit to help make the seal without tearing up the seat it is sealing against.
Mark

How did you remove the broach?

I thought that would be an issue as well but the bit popped right out with a bit of wiggling.