alistairolsen

Any engineers know the answer?

I need to machine up some mounts for wilwood powerlites. Due to the lug mounts on the uprights and the radial mounts on the calipers sharing fixing centres I will have to tap the radial mounting bolts into the alloy adaptor. These will be tpped to a depth of about 20mm on an M10 thread.

Can anyone tell me what grade of alloy bar I should be using (need 20x40 bar) and also should I helicoil it ( only 1.5 times dia deep iirc) and am I best to use standard or fine pitch bolts? Fine is better for torquing up, but caure pitch might take a better thread in the aluminium?

Cheers

nilrem

unsure as to the rest of the answers, but dont tap ally in metric fine... the threads will rip out. metric coarse FTW.

Heli-coils will add strength to the thread and i would recommend them, just incase you have to do runnig repairs!

put some copper slip on the bolts going into the tapping block, as the steel and ali will react, causing the bolt to be hard to remove in the future!

hope this hels a little!

polly_x

iTrader: (2)

Alistair, just buy them from Rally design instead of trying to make your own. They have them on the shelf and unless you are using some odd upright cant see it being a problem. They also sell the spacers for position both the mount to the upright and the radial side to the caliper.

Job done. I think the powerlite uses a BK56 mount bracket but best check with them.

Stu

alistairolsen

do they have off the shelf items for mazda mx5 uprights?

I fugured with the thread pitch. not sure if 2x diameter in alloy or 1.5 times diameter in helicoil is better, the helicoil is only threaded into the allow afterall!

Point taken on the copperslip, altho Ill probably use loctite for peace of mind but it whould provide the same effect

robbieg

iTrader: (9)

I'd say HE30 or HE15 grade alloy.

alistairolsen

HE30 is easy enough to get. Any particular reason? I have no ideas of the properties so any extra infirmation is always interesting!