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Square holes for carriage bolts
Chris_R - 17/7/04 at 09:44 AM

Say for example that you wanna use carriage bolts to hold your master cylinder and pedal box to the bulk-head? Is there an alternative to drilling a hole and using a square file to allow the bolt to fit? Thought carriage bolts may be easier than having a spare pair of hands holding a spanner on the other side of the bulk-head. Rescued attachment carriage_bolts.jpg
Rescued attachment carriage_bolts.jpg


James - 17/7/04 at 10:11 AM

Easier than filing out a square hole?

Can you get the carriage bolts in high tensile?

I'm not sure I'd bother! Holding a nut/bolt has got to be less effort than filing!

All the best,
James


Chris_R - 17/7/04 at 10:16 AM

Well, less time consuming. The theory is that once you've put the bolt in the hole you can still hold in on the threaded side. Besides, eager for the machines to take over the world, that way I can become the chosen one.

[Edited on 17/7/04 by Chris_R]


chris.russell - 17/7/04 at 10:22 AM

why don't you just put a small tack weld on either the nut or bolt? what way you can still remove the pedal box on your own


Chris_R - 17/7/04 at 10:36 AM

I'd try to deny that that's a good idea, but it would be futile. Cheers Chris.


madforfishing - 17/7/04 at 06:15 PM

I expected you to quash that idea with ' My bulkhead is made of Aluminium! '


Chris_R - 17/7/04 at 06:37 PM

It's not done yet so I do have the option. Plus, I've got a large alu panel to use up.


nicklondon - 18/7/04 at 08:22 AM

i have only ever used carriage bolts in wood, the square bites into the wood as you tighten the nut.


Chris_R - 18/7/04 at 10:35 AM

The thought struck me when I was putting my steel weights bench up. It uses carriage bolts with wing nuts for ease of assembly.


DaveFJ - 19/7/04 at 08:06 AM

I was considering using carriage bolts for my seat runners - just so I don't have bolt heads sticking out and spoiling the lovely fully panelled flat bottom .....


Terrapin_racing - 20/7/04 at 01:42 PM

You can get special washers which have two tabs - one sits against the bolt head flat (to prevent it turning) and the other goins into a small hole drilled adjacent to the bolt hole - can't recall what they are called?
Also bolt locking plates - see centre of photo Rescued attachment special.jpg
Rescued attachment special.jpg


DaveFJ - 20/7/04 at 01:46 PM

you mean tab washers ?


Terrapin_racing - 20/7/04 at 01:55 PM

yes - how did I miss that one .


Peteff - 20/7/04 at 05:26 PM

Thinking of spending a lot of time under there are you?. The MOT tester will really appreciate it though, nothing to snag his barnet. Tab washers are for getting muck out your ears round here.

[Edited on 20/7/04 by Peteff]


dmottaway - 20/8/04 at 04:12 PM

thought you might be interested in this. its is a bit out of date, but might be an interesting hunt.

also, if the metal you want to put the hole into is not too thick (or you have Popeye type arms) you could use a panel, or sheet metal, nibbler to square up a drilled hole.

be aware, though, that the metal has to be at least as thick as the shoulder on the bolt lest you have a problem getting the pedal box to sit against the bulkhead.

dave


mad4x4 - 23/8/04 at 03:27 PM

Use a bench grinder to grind off the "flats" leave a small taper so as it pulls into the hole it tightens up.


MikeP - 25/8/04 at 05:09 AM

http://upper.us.edu/faculty/smith/reuleaux.htm


silex - 30/8/04 at 12:31 PM

You can drill square holes if you really want, but it is a bit of a clart on.

No this isn't a joke - yes you can drill square holes.

Requirements:

1 x drill bit - triangular in design.
1 x square hole template.

The drill is not fluted in any way, just flat side and it should taper to a point at the end - a bit like a triangular needle file (in fact they are excellent drills for small holes)

Note, if it does not taper, you will need to drill a round hole to start with, big enough to slide the triangular drill into.

The drill has to be harder than the metal you cut and the hole template harder than the drill (otherwise your template goes bye bye)

Place template onto metal to be cut and fix firmly. Start to drill into the middle of the template hole. Once the drill has pierced the metal you will feel it start to bounce around inside the jig plate. After a short time, all the material is removed and the hole will match that of the jig plate.

Depending on your triangular drill and the size of the hole you may get slightly radiused corners.

It works fantasically in aluminium, and very good in thin steel. I have personally done 12mm thick ally and 5mm of steel.

Also, its more economical if you have a large number of holes to cut.


silex - 30/8/04 at 12:35 PM

Sorry MikeP, I should have looked at your link first - Doh !


MikeP - 30/8/04 at 11:13 PM

LOL, np. I thought the article was a little academic, good to hear it can actually be done!