18Watt.com

lavrgs wrote: ↑

Mon 05/31/21 7:12 pm

Josh do you prefer us going to Reverb or will you sell direct?

Either way is fine, PM me if you want to get it directly.

Thanks,
Josh

I think I sent a PM but when I check my profile its looks like it's empty...

lavrgs wrote: ↑

Fri 06/04/21 11:08 am

I think I sent a PM but when I check my profile its looks like it's empty...

I didn't get anything, shoot me an email instead. support at jmpguitars dot com

Thanks,
Josh

Just sold a tremolo TMB reverb, so there are now officially 3 tremolo tmb reverb owners

Does that include future owners...?
I am considering making a chassis, that I will call a composite; it would be constructed of machined side walls and use flat aluminum panels for front back and top. I think I've seen the original JTMs did this. Are there any big negatives? - maybe not practical for mass production but since this TMB board is on the larger size my plan to use a Mojotone chassis may have to be adjusted. What would be the ideal chassis size for the TMB Reverb? The "standard" chassis is 17 x 6.5 x 2.5

lavrgs wrote: ↑

Sat 06/05/21 11:15 am

Does that include future owners...?
I am considering making a chassis, that I will call a composite; it would be constructed of machined side walls and use flat aluminum panels for front back and top. I think I've seen the original JTMs did this. Are there any big negatives? - maybe not practical for mass production but since this TMB board is on the larger size my plan to use a Mojotone chassis may have to be adjusted. What would be the ideal chassis size for the TMB Reverb? The "standard" chassis is 17 x 6.5 x 2.5

You will be the proud n°4!!!
I decided to use only dumble type chassis on future tremolo TMB reverb builds. The one I buy are 490x200x65mm. Pretty big, but comfy.
https://www.tube-town.net/ttstore/tt-ch ... anguage=en

Thanks, I'll start a layout based on that chassis size

lavrgs wrote: ↑

Sat 06/05/21 12:15 pm

Thanks, I'll start a layout based on that chassis size

Here's mine:

lavrgs wrote: ↑

Sat 06/05/21 11:15 am

I am considering making a chassis, that I will call a composite; it would be constructed of machined side walls and use flat aluminum panels for front back and top.

How would you attach the pieces to each other? Angle aluminum? Or would you weld it together? I've been making chassis for hi-fi gear from rectangular aluminum extrusions. They're 1/8" thick, sized 10" X 2", 8" X 3", etc. I cut them to length, cut out the bottoms for working inside the chassis, then add front and rear panels that are anodized and engraved. It's a huge amount of time and work cutting all the pieces, and I probably won't continue this process when my current small inventory is used up.

I think there are more off-the-shelf solutions for instrument amps than for hi-fi. And they're cheaper, too. A pre-made chassis for the type of gear I frequently build would cost upwards of $400 if the shop did everything (anodized and/or painted and engraved/silkscreened).

It's a never-ending problem.

Jack

TriodeLuvr wrote: ↑

Sat 06/05/21 4:14 pm

lavrgs wrote: ↑

Sat 06/05/21 11:15 am

I am considering making a chassis, that I will call a composite; it would be constructed of machined side walls and use flat aluminum panels for front back and top.

How would you attach the pieces to each other? Angle aluminum? Or would you weld it together? I've been making chassis for hi-fi gear from rectangular aluminum extrusions. They're 1/8" thick, sized 10" X 2", 8" X 3", etc. I cut them to length, cut out the bottoms for working inside the chassis, then add front and rear panels that are anodized and engraved. It's a huge amount of time and work cutting all the pieces, and I probably won't continue this process when my current small inventory is used up.

I think there are more off-the-shelf solutions for instrument amps than for hi-fi. And they're cheaper, too. A pre-made chassis for the type of gear I frequently build would cost upwards of $400 if the shop did everything (anodized and/or painted and engraved/silkscreened).

It's a never-ending problem.

Jack

My design started yesterday but when I get to a point that it's ready for review I'll post it. With a 19+ inch run I may need some center braces. The cosmetics will probably be some kind of engraved plastic - last time I sent it out and it was too expensive- since I am doing a retrofit on my mill I would like to see if I can make something. That's a ways out - later this summer. I'm at a point where I should sell an amp before I make any more but I like what I have. The Mojotone clone may be used as a donor for transformers or may be sell it.

lavrgs wrote: ↑

Sat 06/05/21 5:15 pm

TriodeLuvr wrote: ↑

Sat 06/05/21 4:14 pm

lavrgs wrote: ↑

Sat 06/05/21 11:15 am

I am considering making a chassis, that I will call a composite; it would be constructed of machined side walls and use flat aluminum panels for front back and top.

How would you attach the pieces to each other? Angle aluminum? Or would you weld it together? I've been making chassis for hi-fi gear from rectangular aluminum extrusions. They're 1/8" thick, sized 10" X 2", 8" X 3", etc. I cut them to length, cut out the bottoms for working inside the chassis, then add front and rear panels that are anodized and engraved. It's a huge amount of time and work cutting all the pieces, and I probably won't continue this process when my current small inventory is used up.

I think there are more off-the-shelf solutions for instrument amps than for hi-fi. And they're cheaper, too. A pre-made chassis for the type of gear I frequently build would cost upwards of $400 if the shop did everything (anodized and/or painted and engraved/silkscreened).

It's a never-ending problem.

Jack

My design started yesterday but when I get to a point that it's ready for review I'll post it. With a 19+ inch run I may need some center braces. The cosmetics will probably be some kind of engraved plastic - last time I sent it out and it was too expensive- since I am doing a retrofit on my mill I would like to see if I can make something. That's a ways out - later this summer. I'm at a point where I should sell an amp before I make any more but I like what I have. The Mojotone clone may be used as a donor for transformers or may be sell it.

Please post a pic when the work is at the point where you're comfortable showing it. I'm also using a mill, but its a bench-top model with limited movement. That really eats a lot of time when larger pieces are involved. On the upside, it's CNC, so I can engrave and fill panels without sending them out. Here are a couple photos of a subchassis I'm building for my current project. All of this is my own work, including setting the PEMs and anodizing the bias panel. It's nice to have this capability, but the work is tedious at times. I often wish I could concentrate on design and leave the mechanical stuff for someone else.




Jack

TriodeLuvr wrote: ↑

Sat 06/05/21 8:05 pm

Please post a pic when the work is at the point where you're comfortable showing it. I'm also using a mill, but its a bench-top model with limited movement. That really eats a lot of time when larger pieces are involved. On the upside, it's CNC, so I can engrave and fill panels without sending them out. Here are a couple photos of a subchassis I'm building for my current project. All of this is my own work, including setting the PEMs and anodizing the bias panel. It's nice to have this capability, but the work is tedious at times. I often wish I could concentrate on design and leave the mechanical stuff for someone else.




Jack

Beautiful work!

Here is the general concept for the composite chassis. Placement of items should be considered "rough" outline, but suggestions are welcome.
Front has 7 holes for pots 1 for input 2 for toggle switches and 1 for a F*nd*er style pilot
Back has IEC hole 5 cliff jack hole 1 switch hole
The side panels are 3/8 thk all sheet metal is 0.06 - may change the top if transformers need more support.
The front and back panels support the top panel but I may add a bracket in the middle with a couple extra screws. While this would not be a production chassis the bare metal is around $20 for the sheet metal and just over $15 for a 24" rectangular bar... most shops would cut to size. Drilling and cutting shapes is up to you...hard ones are PT and IEC...files and nibblers... Bottom line don't start yet 9-)
EDIT UPDATED PDF to include EIGHT volume holes , Cap Can hole, threw in some 9 pin sockets

Steel or aluminum? .06 is fairly thin, but you can use fender washers to strengthen/reinforce the transformer mounts.

Why only 7 knobs? Are you not using reverb or something?

Thanks,
Josh

JMPGuitars wrote: ↑

Thu 06/10/21 3:27 pm

Steel or aluminum? .06 is fairly thin, but you can use fender washers to strengthen/reinforce the transformer mounts.

Why only 7 knobs? Are you not using reverb or something?

Thanks,
Josh

Aluminum for all items.
Hmmm did I count wrong...dang? easy fix...
my first pass uses a spacing of 1.5 inches for the holes. 2 inches for the tubes but is not based on any particular criteria. On the rear I grouped the cliff jacks and offset the switch from that group.

Updated the pdf in the post above

JMPGuitars wrote: ↑

Thu 06/10/21 3:27 pm

...you can use fender washers to strengthen/reinforce the transformer mounts.

I used Marshall washers in mine.

TriodeLuvr wrote: ↑

Thu 06/10/21 8:17 pm

JMPGuitars wrote: ↑

Thu 06/10/21 3:27 pm

...you can use fender washers to strengthen/reinforce the transformer mounts.

I used Marshall washers in mine.

Did it look like this?

JMPGuitars wrote: ↑

Fri 06/11/21 6:02 am

TriodeLuvr wrote: ↑

Thu 06/10/21 8:17 pm

JMPGuitars wrote: ↑

Thu 06/10/21 3:27 pm

...you can use fender washers to strengthen/reinforce the transformer mounts.

I used Marshall washers in mine.

Did it look like this?

marshall-washer.jpg

I use that at amplifier shootouts.

TriodeLuvr wrote: ↑

Fri 06/11/21 9:17 am

JMPGuitars wrote: ↑

Fri 06/11/21 6:02 am

TriodeLuvr wrote: ↑

Thu 06/10/21 8:17 pm

I used Marshall washers in mine.

Did it look like this?

marshall-washer.jpg

I use that at amplifier shootouts.

Ha!