Torque Arm Installation - Rear Hub - Best Practice?

[portals]

By 2 piece pattern I was thinking of your CNC part but in 2 overlapping pieces, using the two 5mm eyelets and not a jubilee clip. Then precise orientation of the 3 holes and the flats is no longer critical, in fact the holes can be oversize, exhibit waterjet taper and what not. Just take out the slack by applying the opposite of in-service load to the 2 parts before torquing up.

Having two arms linked might give more scope for lining everything up however again there is an obvious weak link in the connecting bolt?

Surely better to just have one piece that is a good fit?

You lost me at 'exhibit waterjet taper and what not '...

 

[lenny]

waterjet taper

The Spraying Tapir at Newquay Zoo c. 2000

Remember This? Pictured is our much missed (but only by some) interactive highly educational sign about Tapirs at Newquay Zoo c. 2000 – 2005/6. It is based on one at Rotterdam Zoo that I sa…

newquayzoohistory.wordpress.com

 

[portals]

Also - a smear of jbweld between the matting faces might reduce the shear strain on the screws

Nice idea but I wouldn't then easily be able to take off TA for example to fix a puncture?

Will look in to what I need for stronger 5mm bolts, current ones are probably over 20+yrs old but still look good, they've led a stress free life so far as only ever held the derailleur guard on ;-)

 

[saneagle]

The only comment I have is that mild steel is better than nothing, but harder steel would be better, so whoever cuts it, ask them to make it from the hardest steel they have. Apart from that, it looks pretty good. I made some custom ones out of 5mm plate in two halves with the hole open on one side to get the grinder in to make the axle profile, then I welded the two halves together to make the enclosed shape.

 

[matthewslack]

For a perfect fit I would either make from scratch by hand, or limit CNC to the axle hole. Then drill the 5mm holes with the part in situ.

 

[Nealh]

A one piece TA design means there is no nut /bolt join to fail or move.
When I need a TA , I make my own from what ever steel I have laying about.
2mm/2.5mm is the thickest I have used and have had no issue with the thickness.
The critcal point is drilling preping the axle hole for a snug fit, drill, dremel and small files are the tools I use.

Make the TA larger then needed, once the TA fits over the axle snuggly align/drill any fixing holes . Then one can shape the TA.

For my BPM front hub I made two TA's to fit the crappy Suntour forks.
Rear hubs I use just one on the brake side.