Marshall 20 watt kit or chassis available?

[Matthews Guitars]

Does anyone know if there's an aftermarket (or even a used) chassis available for the 20 watt lead and bass Marshall design?

That'd be a 2061 (original) or 2061X (reissue) by model number, or 2017 in the PA version which was never reissued.

The reissue will have different back panel punchings as compared to the original.

I have an original 2061 and a friend has the 2061X. And I want to build another one for myself, just because...and because I already have a set of
transformers for it. Ebay bargain, how could I pass it up?

[WhopperPlate]

Not the exact same but can fit the same
Circuit

https://www.tubesandmore.com/products/c ... 8-watt-tmb

[cdemike]

I'm guessing based on the back panel piece that you have a back plate and maybe a faceplate too? If not, I'm pretty happy with my Modulus chassis. I didn't run into issues with shipping from the UK (may not be an issue for you, depending on your location), and Michael was great to work with. I chose Modulus over others because their aluminum chassis are thicker than most other brands I could find, but my amp has some very large transformers, so that may not be a concern for you.

[Matthews Guitars]

I'm actually more interested in a true replica of the 20 watt lead & bass chassis, I was just checking to see if one already exists.

I love the simplicity of the model, just a volume and a tone knob for each channel. It has a purity and harmonic complexity to it that I think is easily lost in more complex circuits with a full suite of tone controls.

I have a '73 built original. It has quickly become my favorite amp, its responsiveness and harmonic complexity is just otherworldly. I want another one for a stereo rig.

I absolutely have the option to have new chassis made to exact specs. And this may happen. I already make Marshall spec (highly precise replica) front and rear panels for JMP restorations, adding this model's back and front panels is just routine business for me.

[cdemike]

I'm actually more interested in a true replica of the 20 watt lead & bass chassis, I was just checking to see if one already exists.

I love the simplicity of the model, just a volume and a tone knob for each channel. It has a purity and harmonic complexity to it that I think is easily lost in more complex circuits with a full suite of tone controls.

I have a '73 built original. It has quickly become my favorite amp, its responsiveness and harmonic complexity is just otherworldly. I want another one for a stereo rig.

I absolutely have the option to have new chassis made to exact specs. And this may happen. I already make Marshall spec (highly precise replica) front and rear panels for JMP restorations, adding this model's back and front panels is just routine business for me.

That'll be a cool rig! Aluminum isn't terribly difficult to machine, especially if you're patient and do things the "right" way. I machined said Modulus chassis myself using hand tools. Results weren't my prettiest or most precise work, but if I had access to a drill press (really more space; I live in apartment) I'm pretty confident this chassis would be much prettier. I needed to drill holes to mount my transformers, route transformer wires, make space for a rear panel switch, mount a standalone rectifier (like the ones in 50w JMPs), and to mount the circuit board. Even with my caveman setup all of the above worked out fine. In any event, you'd really just need a punch, a hammer for the punch, a drill press, some reasonably sharp bits (step bit would also work fine), and some cutting fluid, you'd be in business for any round holes you'd need to make and probably get both precise and presentable results. Square holes are slightly different, but a step bit and an angle grinder would get you there. If you do the machining, remember to get a de-burring tool.

[Matthews Guitars]

I won't have the time or the inclination to hand make the chassis. I work full time and commute. I'll instead draw up prints for the chassis based off the original,
email them to my local sheet metal shop, and have them make a run of them. Maybe 10 pieces, whatever it takes to get a good per unit cost. And then, I'll use one for my project,
and offer up the others for sale at a reasonable price. I'm sure they will sell.

[cdemike]

Sorry, I was imprecise with my language. Rather than scratch-build a chassis, I was suggesting you pick up a JTM45 or 18-watt style chassis without holes drilled yet and drill the holes to match your plates. Those are easy to come by and will probably a lot cheaper than hiring a machine shop to put together aluminum chassis for you. You'd really just need the tools I mentioned (plus a power drill) and the chassis, but in total, I doubt you'd be out more than $150. If you're really not feeling confident about it, just start with a thinner chassis that'll be easier to work on like:
https://www.mojotone.com/Undrilled-Aluminum-Chassis

A higher quality option like this might check the boxes; I don't have access to 2061 faceplate measurements, but Modulus does make their chassis measurements easily accessible:
https://modulusamplification.com/18w--- ... 3037-p.asp

If you do end up getting those made, I don't think you'll have too much trouble selling them, though. So probably not a bad option, but it might be significantly more involved on a logistics side.