Neck suddenly needs a shim

[eukatheude]

Hi. I've this (allegedly) Fender body with a Roytek fretless neck stuck to it. The truss rod wasn't strong enough to keep it straight, so i tried unmounting and reverse clamping it. It didn't help, and moreover now i can't setthe action low enough. I don't recall there was a shim in there when i took it apart (weeks ago) so i'm wondering what the issue is, since i did nothing to the pocket or the neck heel. So it must be a mounting issue. What have i done wrong?
(And by the way, any way to check if the body is actually a Fender? There's no serial number or Fender neck plate, though the pickups don't look, and more importantly don't sound, like Krapteks.)

[eukatheude]

Anyone?

[mongo2]

Originally Posted by eukatheude

moreover now i can't setthe action low enough.

I often use a flat shim for cases like this. It's easy enough to try one and see if it helps.

If not, the next thing I'd try is a reverse shim.

[eukatheude]

Flat shim as in a shim that covers the whole heel? What do you suggest to use as material? I only have the most minimal tools available, as in a screwdriver and a pair of scissors.

[Scott in Dallas]

Card stock, like from business cards will work.

[mongo2]

Originally Posted by eukatheude

Flat shim as in a shim that covers the whole heel? What do you suggest to use as material? I only have the most minimal tools available, as in a screwdriver and a pair of scissors.

I've used layers of masking tape for flat and wedge shaped shims. Business cards or other thin pieces of non-corrugated cardboard also works. I've even used the flat plastic promotional "credit" cards I get in the mail all too frequently.

I also use bass wood of various thickness from the hobby shop for full pocket shims.

[Growly Lytes]

We know how to get the action right again but the question is.....
What caused this to happen ?