Problems with my chassis.........

Brentsp · Post by **Brentsp** » Thu May 12, 2005 3:22 pm

The chassis itself has pre drilled threaded holes to mount to the headcab, not the snap on clamps that you can change out. When I was mounting the chassis back into its headcab I had problems with the bolt screwing into the chassis hole. When I would look at the bolt after trying the bolts threads were eaten and smoothed off about 1/2". I tried new bolts and it does the same exact thing. So the problem lies in the chassis holes itself. The threaded holes are somehow not lining up with the bolt right and eating the threads. What do I need to do to fix this? Get some dye bits with threads and re-drill into the holes to make new threads? This is on my bogner XTC btw.

Post by **VelvetGeorge** » Thu May 12, 2005 3:28 pm

You can try rethreading the holes with a tap. But your chances of success are about 50/50. How thick is the chassis where the threaded holes are?

George

Brentsp · Post by **Brentsp** » Thu May 12, 2005 3:30 pm

With out looking at it its maybe 1/8"

Post by **VelvetGeorge** » Thu May 12, 2005 3:33 pm

You could punch 3/8" square holes and put in cage nuts. Just an idea.

George

Brentsp · Post by **Brentsp** » Thu May 12, 2005 3:51 pm

VelvetGeorge wrote:You could punch 3/8" square holes and put in cage nuts. Just an idea.

George

Hmmm.....how does the cage nuts stay in place? BTW I just got off the phone with Bogner and the chassis is hardened steel. He said the bolts would probably go before the chassis hole.

Billy Batz · Post by **Billy Batz** » Thu May 12, 2005 3:54 pm

They have like a little snap and groove action. The grooves catch inside the square hole. Check it out youll see what I mean. http://www.metroamp.com/store/product_i ... ucts_id=76

Brentsp · Post by **Brentsp** » Thu May 12, 2005 3:57 pm

Billy Batz wrote:They have like a little snap and groove action. The grooves catch inside the square hole. Check it out youll see what I mean. http://www.metroamp.com/store/product_i ... ucts_id=76

Ah yeah thats the same ones on my metro chassis.

Post by **VelvetGeorge** » Thu May 12, 2005 4:53 pm

But you'll have a hard time stamping the squares in your chassis if it's hardened. You might try the tap idea first and see where it gets you.

George

dynaman · Post by **dynaman** » Fri May 13, 2005 4:19 pm

Try running a screw through the problem hole with the chassis out of the cabinet. If the screw threads properly, put the chassis back in the cab and install a screw in THAT hole FIRST. Leave it loose so the chassis can moved around some to properly thread the other screws. The hole alignment between the cab and chassis might be off slightly and can be cured by drilling the cab's hole to a slightly larger size.

If the hole still doesn't accept a screw (and the chassis really is hardened steel), then you should clean the hole with a tap of the same size and gage of the original screw. There's a good chance that there are screw shavings jammed into the hole.

If this doesn't work and youfind that the threads in the chassis are just plain bad, you drill and tap to the next size. Or you could drill and tap a new hole next to the bad hole.

If the chassis' mounting ears are the kind that bend to the outside, you could just use a regular screw with a nut.

Do yourself a favor and make sure the screws you're using are soft. Don't use stainless, hardened black oxide, or grade 8, etc. If a soft screw gets out of alignment and you keep forcing it, the screw will destroy itself rather than destroy the chassis threads.

dynaman · Post by **dynaman** » Fri May 13, 2005 4:23 pm

Oh yeah, make sure you're using the proper screw! An english screw will thread into a metric hole for a few turns before jamming up.