The Steel Guitar Forum

I have a 20-year-old Session, and I have a problem with the face plate that holds the LKR moving lever. The plate is secured by two bolts. On one of these bolts, the hex head has been damaged (through repeated use of the wrong size allen key probably ) and I can no longer get it to turn.

So I have two questions :

1) what can I do about the defunct head ? Presumably, my best bet is to get the damaged bolt out and then replace it - but how to get it out ?
2) what size allen key should I be using anyway ?

mickd..A small pair of vice grip pliers, if it is where you can access it. An "easy-out" if it's recessed. If you are "mechanically challenged" (nothing personal intended)take it to a machine shop, they will have the tools to remove it.Should not cost much.You can probably get the bolt, and wrench there also.

In the U.S., we have what we call "nut houses" where they sell nuts, bolts, screws, etc you can purchase the proper size allen bolt, and wrench.

BF

I know in some situations the wrench goes bad rather than the bolt...if this is your problem just grind the wrench down til it gets past the part that has been worn off. Just a thought...Bill

The bolt head is flush with the side of the guitar, so it would have to be an 'easy out' - thanks.
Its definitely the bolt head itself that's damaged - you can see where the hex edges have been worn away.
I'm hoping a fellow Sierra owner will tell me what size allen key he's using - don't want to bother Tom over such a trivial thing.
(we have 'nut houses' here too, but I'm steering clear in case they insist on me moving in )

On my Sierra's, they are 9/64.
Hope that helps.

Roy
Thanks. I took a look in my Session manual & it has a diagram showing the bolts and it has them labelled as "10/32" so maybe this is something that has changed over the years.
Someone told me that "9/64" "10/32" and so on tells you something about the pitch of the bolt rather than the size of the allen key you need to engage the bolt head
Mick

Sometimes a damaged hex. head can be removed with a Torx bit - if you're lucky.
Tony

Mick,
on my Sierra Crown the Allen head size of the bolts that hold the plate of the mobile knee lever brackets ("hub assembly") is 1/8" (one eighth of an inch, roughly 3.2 mm).

9/64" would be nine sixty-fourth of an inch or 3.57 mm. The number combination 10/32 measures screws and bolts, where 10 is the screw size and 32 the number of threads per inch. 8/32 would be a smaller screw with the same number of threads, 10/24 would be the same size screw with less threads. The length of the screw has to be specified additionally, like 10/32 x 3/4": three quarters of an inch long.

Aren't you glad you all switched to metric on the island?

If I had your problem on my Sierra, I'd drill out the bolt and put in a new one. If the threads in the plate were damaged in the process, I'd tap a new metric thread.

Good luck,
Rainer

Well, I just went through a box of allen keys belonging to a friend of mine and I found one that fits really well - haven't tried loosening the bolt yet, but it looks like it should do the job. Good to know that alternative remedies (Torx, Easy-out)exist should I make a mess of it.

I still don't know what size this latest key is - though from what Rainer says, I'll guess it's 1/8". I think the key I was using before was 3mm, which would explain the damage

I've got a box of allen keys and half of them are metric and half Imperial and I don't know which is which

Thanks for all the help

I have replaced the bad screws with standard sizes of torq screws and no longer have a problem.