Amp Chassis

[Structo]

I recently bought a 17x8x2.5 aluminum blank from Watts Audio.

I wanted room to work!

Wasn't going to paint it but the aluminum had some marks on it, like from the rolling mill.

So I painted it black.

I used Rustoleum Self Etching Primer
Then top coat or 4 Gloss Black Acryilc Lacquer.

Takes forever to dry/harden.

[Littlewyan]

Fowler's black steel chassis with the grey cage on top looks pretty cool. I saw a 6AQ5 Marshall in another thread fit into one of these as well. Think about it, it looks like its supposed to be nice clean hi fi, but really its a mean gain monster

[Phil_S]

I used Rustoleum ... Takes forever to dry/harden.

Yes, you really have to be patient and careful with Rustoleum. Unfortunately, it is stinky, too. My experience says you need to leave it in warm dry place for at least 48 hours before handling it, and preferably 5 days or so. In the cooler weather, I leave it in the basement where the furnace lives. In the a/c season, the den windows face west and it gets toasty in the afternoon. Once it cures, it is very durable. I like white.

[TUBEDUDE]

You might be able to find a local business that will powder coat the chassis.

[Littlewyan]

I once painted a pedal I built. Started with few coats of primer, about 4 coats of the actual paint and then lacquer. I sanded down between each coat with finer grit paper each time and finished it off with TCut to make it shine. It had a pretty good shine to it, bit scratched though as I didn't sand it with fine enough grit paper before the TCut but it as good for a first attempt.

Would I do it again...............hell no! Least not without a workbench next time or a room where there is no wind or dust. I had to do it in my garage without a workbench and kept getting dust and all sorts on it. Was an experience though.

[davent]

How big/small are you looking to do? I've done a couple small builds with flat pack transformers and get everything inside a regular 2" deep chassis.

Last one...
[IMG:800:600]http://i216.photobucket.com/albums/cc30 ... 8b4c96.jpg[/img]

[IMG:800:600]http://i216.photobucket.com/albums/cc30 ... 0e8f91.jpg[/img]

[IMG:800:600]http://i216.photobucket.com/albums/cc30 ... ab4861.jpg[/img]

[IMG:800:600]http://i216.photobucket.com/albums/cc30 ... 1f126f.jpg[/img]

[IMG:800:600]http://i216.photobucket.com/albums/cc30 ... 5e2373.jpg[/img]

[brewdude]

Thats pretty awesome.

[xtian]

Last one...

Woah! Who are you? (This is where you say, "I'm batman.")

Super nice build!

[JMFahey]

Beautiful build, congratulations.

[John_P_WI]

Yes, definitely a beautiful build. There is a lot of KOC / TUT influence there...

BTW, I'm really digging the remote power scale pot, the whole build looks like a piece of lab test equipment.

Beautiful....

[Littlewyan]

That looks great! What about heat? I bet it gets quite hot in there.

In answer to your question I'm not sure yet, I'm just getting together ideas for what I COULD build. There are a number of amps I do want to build such as a JTM45, TW Rocket and a single ended amp (RJ's Eagle Supre maybe). Just looking for different ways of doing it as buying a head cabinet each time is quite expensive. The head cab I bought for my TW Express head was £136 and the one for my JTM1 was £98!

I may even build my own head cabs yet, thats another idea...

[johnnyreece]

I just picked up a chassis-like object today. The maintenance department of our school system has a scrap pile, and they gave me free rein to pick through it today. Wahoo! Picked up one for-sure chassis, one that might work, and an old PA speaker with the 70v transformer attached (might be able to do something with it...). Maybe I'll decide what my next project will be soon, and actually do something!

[davent]

Thanks everyone for the kind words!

Heat isn't an issue with the small build, the backplate is totally perforated so air flows freely through and the power tube's a little 6aq5, hot at the top end but at it's base not so much, was a concern but the laser thermometer shows not something to worry about.

With what you've described for builds, this isn't a style that's going to work for those you have in mind.

How're your metal fab skills, Blaze Amps has some interesting approaches for open chassis builds.

Can't get a direct link the gallery so be sure to check it out.
http://www.blazeamps.com/

KOC, yup! The style i had used in hifi builds, horizontal tubes inside, flat pack trasformers, (the most economical power source for these little amps i've found in Canada so far), shaft extenders, mix of pcbs/eyelet boards etc.. Some of that covered by KOC. Directly from KOC, the power scaling circuit, current regulated heater supply (KOC/Morgan Jones and others), much of the power supply nuances, voltage clamp for the preamp, did use a circuit from a phono pre for that. All 'n all big influence, one of many.

Fun way to build small low powered amps.
Thanks again
dave