Using stainless steel chassis

[beasleybodyshop]

So I made up several SS dumble style chassis yesterday - any disadvantage to using this? Can I still bolt solder lugs to chassis and maintain a good ground?[/b]

[menger66]

If it's stainless weld ground lugs, seems like stainless would be very hard
on drill bits, could you post some pix? mark

[Leo_Gnardo]

Can I still bolt solder lugs to chassis and maintain a good ground?

Sure why not? I always scratch up the surface where lugs are to be mounted no matter what metal and/or finish, hoping to let the lug get a better grip on metal not paint, oxides, anodization (oxide again), and even stainless.

Disadvantage is your chassis won't rust, in case you like that look.

Some audiophools claim SS isn't a suitable chassis material because the magnetic properties are different from ordinary steel, but I havent' run into any problems on the SS chassis I've rarely seen. You would have to build identical circuits on different chassis and listen real hard to pretend you could hear the difference.

[JazzGuitarGimp]

You would have to build identical circuits on different chassis and listen real hard to pretend you could hear the difference.

And with component tolerances and slight differences in lead dress, how can we even be sure the two circuits will truly sound identical to begin with?

[beasleybodyshop]

Thanks for the insight Leo.

I made like 10 of these SS chassis, I couldn't let that fancy mirror finish stuff go to waste!

[beasleybodyshop]

My only bitch is going to be drilling holes in it.

[gktamps]

Cobalt drill bits for the smaller stuff. It's going to be tough for the larger holes. Laser or waterjet cutting would be the trick.

[beasleybodyshop]

Cobalt drill bits for the smaller stuff. It's going to be tough for the larger holes. Laser or waterjet cutting would be the trick.

I dont have access to a either of those things, I wonder to myself how quickly i would destroy a forstner bit on super low speed

[katopan]

Real, real slow and keep it cool by cooling fluid or only doing a tiny bit at a time. Once it heat hardens it'll be an absolute battle.

[Leo_Gnardo]

You would have to build identical circuits on different chassis and listen real hard to pretend you could hear the difference.

And with component tolerances and slight differences us lead dress, how can we even be sure the two circuits will truly sound identical to begin with?

Good question. Few to none would bother doing the comparison builds and making the comparison and I have a feeling the items you mentioned plus differences in tubes would swamp any difference due to chassis material.

[jaysg]

You want to use Loctite thread locker on the threads of machine screws and nuts where ground is made. I recommend Kep Nuts (have a washer attached). The washer digs in for better electrical contact. It's ugly, but you might also want to tap any holes used for ground. I use a lot of nylok nuts for normal mechanical stuff.

If you have to do any drilling, you need a drill press. Hand held will just skid, even with a center punched starting point.

[Tubetastic]

You want to use Loctite thread locker on the threads of machine screws and nuts where ground is made. I recommend Kep Nuts (have a washer attached). The washer digs in for better electrical contact. It's ugly, but you might also want to tap any holes used for ground. I use a lot of nylok nuts for normal mechanical stuff.

If you have to do any drilling, you need a drill press. Hand held will just skid, even with a center punched starting point.

Interesting point regarding Center-punching on here about drilling/centerpunching SS:


Centre punching with conventional conical shaped punches can result in enough localized work hardening to make drill entry difficult. This can make the drill tip deflect or wander, glaze the surface and/or blunt the drill tip and result in drill breakages, particularly where small diameter holes are being drilled.
Where a punch mark is needed to help get the hole started, a light mark using a three-cornered pyramid tip punch is a better idea.

[TUBEDUDE]

Chassis punches work better than drill bits for the larger holes, say 1/2" or larger.
The lads at Weber blue printed and amp on steel and stainless with no real difference. See the Weber site.
I wouldn't ruin my forschner bits on metal, I use those for wood only.

[Diablo1]

Can I still bolt solder lugs to chassis and maintain a good ground?

Some audiophools claim SS isn't a suitable chassis material because the magnetic properties are different from ordinary steel, but I havent' run into any problems on the SS chassis I've rarely seen. You would have to build identical circuits on different chassis and listen real hard to pretend you could hear the difference.

Two categories of stainless steel, ferritic and austenitic. Ferritic stainless is ferromagnetic, like plain carbon steel. Also, lots of folks have built amp chassis using aluminum too. Aluminum isn't ferromagnetic. If you don't use a ferromagnetic material, then you don't get any magnetic shielding. However, it's unlikely you need magnetic shielding for amps.

[Mescalero]

You may find that it has lower thermal conductivity than aluminium too. That is, if you count on it for heat sinking considerable power in small areas.