LOL, how do *you* like to remove / install a tweed chassis?

[King Fan]

I've done this a ton now, but every single time I think "there's gotta be a better way." I can drop 'em right side up, sorta, tho the PT creates some weird torque. But for install that gets crazy, so I tend to do it upside down with the amp on a carpet or foam block. None of my methods are trivial, stable, elegant, or foolproof. How do you do it? Especially if you have a method you like.

 

[Timbresmith1]

Face (grill cloth) facing down.

 

[D'tar]

 

[Phrygian77]

Face (grill cloth) facing down.

For a tweed?

 

[Lowerleftcoast]

every single time I think "there's gotta be a better way."

The best... with two more hands helping. Rarely does that happen. hah.

 

[King Fan]

And for graduate students, how do you like to do one of those big-iron jobs that has a PT hanger bolt?

 

[Jimy]

Upside down. Let gravity work for you. I put the amp on blocks so that I have good access to the top surface.

 

[telemnemonics]

Little ones get the thumb up and big ones get a bracket supporting the PT end.
Actually I've done upside down too just to start the fasteners.
None are in and out often enough to create shreddy licks!

 

[dankilling]

Upside down to get the nuts and bolts in place, then lay it back onto the back panel. Snug up the bolts and it will be in the right place every time.

 

[D'tar]

Thought they were open to the back so we never had to remove them!!!

 

[JohnnyCrash]

“How do you like…”

I don’t! Haha!

I usually lay it on the floor and lie on my back. I think it’s because my uncle was a mechanic and also because my dad made me hold the flashlight on our own car repairs.

I finally have a workbench, but I don’t think I’ll be building any tweed style chassis hangers to benefit from the new working level.

I’ve currently got a ‘62 Bassman repro (with a PPIMV) I’m starting and a ‘65 (with a hotrodded Bass channel)… those hanging shorties are a pain to install in their own way.

 

[wangdaning]

Put it on its side with something holding the chassis up to the correct height, like blocks of wood or books. More specifically, put it so pt side is at the bottom. Hold the top side with one hand and secure the bolt hand tight. Now you can let go and use both hands to secure the bottom (pt) side completely. Finally, secure the top completely.

Edit: By secure completely I do not mean as tight as possible.

 

[corliss1]

Should need arise to pull a tweed-style chassis, I always put the amp on its side.

 

[telemnemonics]

Love it when the chassis nut falls under the board?
Charged caps or discharged?
This is the time to do dumb stuff!
Kind of dumb to require a small self traveling conductor to be inside the chassis where all the juice jumps at the chance to be conducted.
Gravity needs to be managed here, or as I recall anyhow, I don't like losing small conductors in the chassis!

 

[King Fan]

Heh. So we have right-side-up, upside down, on its side, on its front, and (in part) on its back? The prosecution rests.

FWIW I used my chassis-building cradle yesterday to elevate the amp upside down, spare the handle, get gravity on my side, and retain access to the screws. But it was still a total cluster, especially feeling around for the PT hanger, inserting its bolt, and threading its keps on blindly. Plus the cradle solution wasn't very stable. I'm now thinking I have a cheap generic amp stand somewhere, with padded arms. Not 100% level, but close. Next time...

 

[Mark the Moose]

Glue two short pieces of 1x1 to the cabinet sides under the chassis. Henceforth, when you remove the mounting bolts the chassis will just rest on those blocks.

 

[King Fan]

Glue two short pieces of 1x1 to the cabinet sides under the chassis. Henceforth, when you remove the mounting bolts the chassis will just rest on those blocks.

Now *that's* a good idea. Why didn't I think of that? I did something similar in my Princeton Reverb to help the tray slide into place. There of course you have to make 'em short enough to avoid the chassis bolts, but I picture that's not an issue here.

 

[D'tar]

Glue two short pieces of 1x1 to the cabinet sides under the chassis. Henceforth, when you remove the mounting bolts the chassis will just rest on those blocks.

Works wonder on a blackface etc. Unfortunately the tweed chassis are way more narrow than the cab with inches on either side.

K ing Fan, what tweed are you working? Pt support? Did you build a Bassman without me noticing?

 

[schmee]

You build a new one inside a BF style chassis!

 

[chas.wahl]

Let's see: you could build a 4-sided frame that fits into the amp, height just shy of the projections you can't remove easily (like tubes), width just shy of the battens for fastening the back panels, and depth to suit, but at least that of the chassis itself (2-5/8" or thereabouts). Put holes in the top member of the frame, so that the chassis can be slid in over the top of it, and then clamped to the frame somewhere with the projections in the holes. If you wanted to stabilize the frame and fix it in place for use, you could fasten it with a couple screws to the cab sides (not too deep) that would have holes just ahead of the speaker side of the battens, and therefore not visible unless one's head is inside the cab.

The frame could/should have an outrigger to support the PT, since that's a basic part of what makes installation hard -- the fact that it's an assembly with a poor center of gravity, being somewhere outside the chassis itself. You'd need to have mounting screws long enough to allow the washers and nuts to be installed with the chassis resting on the frame. Once the nuts are threaded on, then unclamp chassis from frame and raise the chassis off the frame using the mounting bolts. Then unscrew the frame from cab sides and pull it out.