1974 XS/TX650 rebuild

**th62** · Jan 9, 2021, 03:45 PM

Here's how they were made. i started with two strips of 3mm ally, 50mm x 230mm. worked out PI for 34mm fork legs and did two 90 degree bends Pi apart. I used a bit of angle iron with the edge radiused for the bends as this aluminium fractures if bent to acutely. I then bent the ally around a 34mm dolly, bringing the 90 degree bends together with a 3mm gap between when clamped tight. Of course I had to stuff it all up when I shaped it, didn't I, made two right handers instead of a right and a left. The joys of getting old. Oh well, soon as I make a lefty I'll shape, drill and polish Some polishing was done beforehand for the areas I won't be able to get to after bending.. I'll post pics of the completed brackets when finished. . i started with two strips of 3mm ally, 50mm x 230mm. worked out PI for 34mm fork legs and did two 90 degree bends Pi apart. I used a bit of angle iron with the edge radiused for the bends as this aluminium fractures if bent to acutely. I then bent the ally around a 34mm dolly, bringing the 90 degree bends together with a 3mm gap between when clamped tight. Of course I had to stuff it all up when I shaped it, didn't I, made two right handers instead of a right and a left. The joys of getting old. Oh well, soon as I make a lefty I'll shape, drill and polish Some polishing was done beforehand for the areas I won't be able to get to after bending.. I'll post pics of the completed brackets when finished.

**NeiljohnUK** · Jan 13, 2021, 10:24 AM

Interesting issue with the side case polishing, granularity from a cold spot during casting perhaps?

I have a fellow BMW boxer owner nearby who polished his engine (R80 sand cast casings) over a winter, had to repolish annually. Though the Ariel Red Hunter owner I met who did the same went so far the casings became porous and wept engine oil, ended up having to paint the inside with epoxy which stopped it to a degree, but as the metal was full of oil it didn't stick too well in some places. Modern water based engine paint is rubbish, my F800 has corrosion under all over, starting at any sharp edge where it's thinnest it creeps until it flakes it off, coat regularly with ACF-50 now to stop it getting any worse!

**tonyfoale** · Jan 13, 2021, 11:25 AM

Originally Posted by NeiljohnUK

the Ariel Red Hunter owner I met who did the same went so far the casings became porous and wept engine oil,

They didn't become porous they started life that way. It was a legal requirement for Brit bikes of that era to leak oil.

**th62** · Jan 17, 2021, 01:22 AM

This afternoon I taught myself to mig aluminium. The key was finding the right volts, wire feed, stick out, speed and watching the heat build up, that had me stumped for a bit, wondered why each successive run was worse than the last - heat build up!. Oh, a steady hand also helps, but that's beyond this old codger now, hence the wobbly runs. Excellent penetration too, after welding an external edge joint, I ground it down flat then belted the hell out of it trying to separate the joint. Not too bad for an hour or so practice. A whole new world of aluminium fabricating has opened up now, should have taught myself to weld aluminium year's ago. Talk about messy though, splatter everywhere. And I burnt the crap out of my arm from flash, the flash is 10 times brighter than when welding steel.

**tonyfoale** · Jan 17, 2021, 03:58 AM

Originally Posted by th62

This afternoon I taught myself to mig aluminium. ........... Not too bad for an hour or so practice. A whole new world of aluminium fabricating has opened up now, should have taught myself to weld aluminium year's ago. Talk about messy though, splatter everywhere.

Are you using the inbuilt wire feed or do you have a spool gun?
I am surprised at the dirty surrounds and splatter, are you using pure Argon or is Aluminium wire available with flux in wire like steel is? Although I have welded aluminium over 6 decades with Oxy/Act and TIG over 2 decades I have only used MIG for steel. I have seen some videos of Aluminium MIG but those showed a cleaner finish.
You have done a great job with such a small amount of practice. I relate totally with your comments on wobbly runs, being fairly ancient myself I am starting to have the same problem particularly with TIG where I have to hold the gun with one hand at least with MIG I can use both hands.

**th62** · Jan 17, 2021, 03:39 PM

No spool gun, so I set the machine to operate properly without one: I used 5356, .8mm wire and drilled out the tip to 1mm, threw away the liner recommended for ally as too much birdnesting and used a steel liner, installed a ribbed feeder wheel and loosened off the wire reel preload.

I have tried before using a disposable argon cartridge with dismal results - not enough pressure.

**tonyfoale** · Jan 17, 2021, 05:17 PM

Originally Posted by th62

No spool gun, so I set the machine to operate properly without one: I used 5356, .8mm wire and drilled out the tip to 1mm, threw away the liner recommended for ally as too much birdnesting and used a steel liner, installed a ribbed feeder wheel and loosened off the wire reel preload.

I have tried before using a disposable argon cartridge with dismal results - not enough pressure.

Years ago I replaced the standard spiral type liner with a teflon version sold for Aluminium welding, I was welding steel but I thought that being teflon the wire would slide nicely. It did that OK but it only lasted about 1/2 day because the wire wore off a fine amount of teflon which formed a thin insulating layer in the tip preventing current flow. That was the second of two of life's lessons about teflon flowing.