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Alive
8th May 2006, 19:52
Anyone in the Auckland know a good place for me to take a couple of small alloy party and have old threads drilled out, sleeved and re-tapped?

I'm in the last stages of piecing an 81 XJ550 together and need the mirrors fixed :)

Alive
8th May 2006, 20:51
Someone.... Anyone??? :rolleyes:

Madness
8th May 2006, 21:14
Any engine reconditioner will have Re-Coil thread repair stuff to do the job cheaply. Providing the studs on your mirrors are a standard size thread.

This involves drilling oversize, tapping new thread (special Re-Coil tap oversize also & non-standard) and inserts which are like a spring. This is a commonly accepted method of thread repair, particularly for threads in softer materials such as aluminium, as you retain the original male thread (often steel) and distribute the stresses to a larger surface area in the female thread of the joint.

The kits sell for up to $100, depending on size, with the tap making up most of that cost. The inserts are only $2 each roughly, so if you only have to do 2holes, use someone elses kit.

Alive
8th May 2006, 21:17
That has been previously done on one, but the thread is right handed instead of left (or however that works) but I believe it could be easily changed with the right coil.

Thanks for that, gives me something to go looking for :)

Madness
8th May 2006, 21:30
Re-Coil also manufacture solid thread repair inserts. They are self-tapping, with 2 notches in the underside. You wind them with a bolt & locknut & can Loctite them in place. They are called Re-Coil Ensat Tapper Inserts, available through Engineers Merchants. Left-Hand Thread repair inserts are probably like rocking horse shit, and repairing them manually would be expensive. I'd look for replacement brackets.

First thing to check.. Thread diameter & pitch (distance between threads). I have come across "Special" threads on bike bits (they dream them up at smoko) particularly on Suzuki's.

An example of different pitches.And approximate assoc. info
M12 x 1.75 = ISO Coarse, Common & available in all manner of fasteners. Tap cost$15, Left-Hand Tap cost$60
M12 x 1.50 = ISO Fine, Reasonably common, you can buy bolts etc. Tap cost$30
M12 x 1.25 = ISO Extra Fine, Japs love this one, Most common on Jap Cars, Harder to find the bolts, but available. Tap cost $40
M12 x 1.00 = ISO Extra Extra Fine, You find it occasionally, Bolts etc hard to find. Tap cost $50

Motorcycles have been known to have fasteners that will fall into the diameter (i.e measure 12.0mm) yet the pitches fail to measure up to anything standard.

Titanium
8th May 2006, 21:44
Machine part welding in Great South Rd Penrose. Do general extraction repair works, have used them on jet ski stuff. Always good work and good price.

Cheers

Alive
8th May 2006, 21:51
Thanks BMW :P

classic zed
27th June 2006, 10:24
I have "Time Serts" for them, basically it removed the thread, re-taps the hole and inserts a bigger steel insert which brings it back to standard.

I have done loads of repairs on bikes and cars with no problems, the kit can even replace damaged spark plug threads.

You can ring me on 09 424 0477 if you still need it done.

Alive
2nd July 2006, 21:27
I have "Time Serts" for them, basically it removed the thread, re-taps the hole and inserts a bigger steel insert which brings it back to standard.

I have done loads of repairs on bikes and cars with no problems, the kit can even replace damaged spark plug threads.

You can ring me on 09 424 0477 if you still need it done.


Hey Zed.... Cheers for that but I got Henderson Motorcycles to throw a coil in it for me, so it's all sorted :)