LSS Chassis Bolt

Dual/Triple Rectos, Maverick, Blue Angel, Nomad, Road King, F-Series, Lone Star & Stiletto

Moderators: Guitarzan, Grandor, ned, Platypus

Vogelsong
Mark III
Posts: 394
Joined: Sun Nov 28, 2010 7:36 am

Re: LSS Chassis Bolt

Post by Vogelsong » Sun Nov 28, 2010 8:16 pm

I needed a laugh today, the funny thing is I just found this screw myself today and was wondering all the same stuff.

You guys are too much.
Vogelsong

G&L Comanche,
G&L Legacy,
RI 64 Vibroverb Custom
Original 66 Fender Reverb,
Original 59 Fender Bandmaster,
69 Fender Coronada II,
51 Gibson ES300,
Beater Strat,
Waldon Acoustic,

rfrakes
Mark II
Posts: 100
Joined: Thu Jun 07, 2012 11:49 am

Re: LSS Chassis Bolt

Post by rfrakes » Sat Jun 23, 2012 3:16 pm

I replaced mine with a cryogenically treated screw! Sounds much better now.

rfrakes
Mark II
Posts: 100
Joined: Thu Jun 07, 2012 11:49 am

Re: LSS Chassis Bolt

Post by rfrakes » Mon Jul 02, 2012 4:53 pm

I would think you would have to back this screw off a bit when sliding the chassis out or you might rip the foil shield.

Is this correct thinking?

Thanks, Ron

MrMarkIII
Dual Recto
Posts: 2828
Joined: Mon Jul 16, 2007 1:01 am
Location: SoCal

Re: LSS Chassis Bolt

Post by MrMarkIII » Mon Jul 02, 2012 7:04 pm

rfrakes wrote:I would think you would have to back this screw off a bit when sliding the chassis out or you might rip the foil shield.

Is this correct thinking?

Thanks, Ron
Yes. Remember to drain the caps, because sticking your hands inside the chassis can kill you.

User avatar
tele twister
Mark II
Posts: 67
Joined: Sun Oct 06, 2013 10:41 pm
Location: Illinois, USA

Re: LSS Chassis Bolt

Post by tele twister » Wed Dec 04, 2013 7:22 pm

Would it be possible for a loose shard of foil to fall down on the circuit board or tube socket and short something? I'm thinking about screwing a small repair plate there, 2" X 2" made of aluminum sheet metal.

My RoV2 had signs of an arcing on a tube socket when I got it,(used). Now I'm wondering if it was a shard of foil. My foil is all chewed up there.
'02 ROV 50 II Combo

Nicklotsaguitars
Mark III
Posts: 283
Joined: Tue Dec 22, 2015 12:15 pm

Re: LSS Chassis Bolt

Post by Nicklotsaguitars » Fri Oct 21, 2016 8:54 am

What that screw is doing is completing a Faraday cage. Contacting the foil of the cabinet it's sending the small charge running through the chassis, to the foil. This stops a lot of EM/RF noise.
As for repairing the foil, a bit of copper tape will work fine.

Recently put my Mark V in a headshell that didn't have the foil. It was a bit more noisy and the footswitch clicked/popped.
Put it back in the combo housing and all is fine.
some guitars and some amps

grritz
Bottle Rocket
Posts: 2
Joined: Mon Sep 04, 2017 5:43 am

Re: LSS Chassis Bolt

Post by grritz » Thu Sep 07, 2017 3:54 pm

I think it says something very positive about Mesa that they would even think about a "tension screw" to help prevent buzzing of the chassis against the cabinet.
I mean...what other amp maker does this?
I'm a Mesa Boogie newbie, but this is just another reason I'm soooo glad bought a Mesa amp!

Thanks, Mesa!

bandit2013
Triple Recto
Posts: 3120
Joined: Fri Feb 22, 2013 7:31 am
Location: North Carolina

Re: LSS Chassis Bolt

Post by bandit2013 » Tue Oct 17, 2017 5:28 pm

The RA100 combo has the same thing going on with the tension screw. Never seen one on the Roadster but there is a square hole in the chassis of the Mark V that appears to have been something deleted.

I guess no screw would make things airy, that is great as I play 'air' guitar most of the time anyway. (I know... to late..... )

Frankolino
Bottle Rocket
Posts: 13
Joined: Tue Jul 25, 2017 5:26 am

Re: LSS Chassis Bolt

Post by Frankolino » Tue Jan 02, 2018 9:51 am

Well, the screw is not therefore to make contact with the foil. Because there are 4 screws on the underside of the chassis to make contact to the foil and make a faraday shield to protect against RFI.
You can see that very well in the picture of a Nomad 55W I found in the internet.
( Bare screws on the left and right )


Image

Post Reply