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Thread Chaser Size

mountainman

Jedi Trainee
Offline
The captive fender nuts on my 1959 tr3 are in bad shape and in need of cleaning the threads. Can someone tell me what size thread chaser I need and where would be a good place to buy one?
Thanks
Greg
 
1/4"-28...you can use a regular tap that should be available at any decent hardware store or Home Depot. I chucked the tap in a variable speed reversible drill which makes things go much faster. Just be careful when first starting in the thread so you don't cross thread it.

Edit: If you can find a spiral point tap , that will work much better at getting the tap started correctly. You may have to go to a machine supply place to find one of those however.
 
Just FYI, A lot of those captive nuts will spin inside the cage if you don't use a pair of vice grips or channel locks to hold the tabs as you thread.
 
rlandrum said:
Just FYI, A lot of those captive nuts will spin inside the cage if you don't use a pair of vice grips or channel locks to hold the tabs as you thread.
I do have a couple that are turning 2 inside rear fender well and one on the very back of the rear fender. That was my next question "how do you get to them to keep them from turning?
ps; I will oder the sirial point taps
Thanks alot
Greg
 
mountainman said:
That was my next question "how do you get to them to keep them from turning?
If they are already turning, then your only hope is to get in there somehow and pinch the cage shut on the nut. I found that "needle nose vise grips" would reach most of them, but sometimes you just have to cut the bolt or grind the head off to gain access to the caged nut.

To keep them from spinning in the future, I chase the threads with a tap every time, and use copper-based anti-sieze on the bolts, every time.

Been using an old 1/4-28 tap & tap handle mounted on an air ratchet for chasing the holes; but that might be a little violent for most folks. Haven't ruined a nut yet, though.
 
I used a set of these...

42275.jpg


The ones at the bottom (with the rounded nose) work great. They also work well for removing damaged cages so new ones can be welded on.
 
Thanks again,
rlandrum I'll see if I can find a set of those pliers.
 
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