Using a helicoil to fit a gear shift knob

[untakenname]

Hi, I'm looking at getting a heavier gear shifter and have found one I like but the thread size I need (M10x1.25) is discontinued, could I get one that's M12x1.25 and then use a M10x1.25 helicoil to reduce the size so it fits?

Looking at the specs on the helicoil website the outside diameter for an M10 insert is 12.10mm which is .1mm outside the limit but could always drill it out.

I've never used a helicoil before so don't know how much force is needed to insert one, could I wrap the gear knob in tape and some cloth then put it in a vice or would it be likely to slip and ruin the finish? It might probably be best to clamp the helicoil tool instead but don't know how much leverage is needed to put one in.

Cheers.

Edited by untakenname on Sunday 14th February 15:09

[steveo3002]

id go with a bit of oil wiped on the gearstick threads , then smear epoxy glue inside the new knob and plonk it on , should be plenty strong enough and will unscrew as normal

[untakenname]

Cheers, using expoxy hadn't occured to me, may give it a go first and see how well it holds up.

I've got a few M10 thread bolts so will practice with them, have some JB weld around somewhere.

[paintman]

Drilling out the hole & cutting the new thread with the helicoil tap are the bits that might need the knob to be clamped. Putting the helicoil itself in requires little effort.

[anonymous-user]

I would use a thin walled plastic tube, insert it into the knob and screw the knob in. A lot of gear knobs were plastic/rubber literally force fitted. I've done this on a ford type 5 stick and it works well, I used thread locking stuff too but can't remember which but it's brilliant