Sheet Metal Gauge

kafka007 · 11th November 2006, 08:43 PM

I'm building a fairly standard tube amplifier chassis using a sheet of brass screwed into a wooden frame. It'll be supporting 3 fairly heavy transformers (pwr + 2 opt), a choke, caps and of course the tubes. I was thinking of using brass. What gauge material do you recommend for such a top plate?

jayme · 11th November 2006, 09:10 PM

You could get some steel support rods or flat bars and make a support cross under the top plate. You wouldn't need much, and the extra support would make the brass gauge relatively moot.

Also, if you could roll the edges on the brass, it would structurally re-enforce the load support. Cut a notch out of each corner and roll each long edge.

Tom Bavis · 11th November 2006, 09:22 PM

I've used a metal angle under the transformers to strengthen it (you might be able to locate it so that the transformer bolts go through it).

leadbelly · 12th November 2006, 01:22 AM

You'll be good with 1/8" or 8 ga. sheet.

HollowState · 12th November 2006, 02:54 AM

A sheet of 1/8th inch brass will cost you a pretty penny to say the least. It will also tarnish easily unless you clear lacquer it. Why not use aluminum plate? It's just as functional and a lot less money. Just be sure to get a piece that's tempered. The most common is 6061-T6. (or T-351 or T-651) Tempered aluminum machines very nicely and is not gummy. Or use a piece of aluminum rack panel.

I also prefer to support a standard chassis with aluminum right angle strips that I buy at Home Depot. (no affiliation)

Victor

Geek · 12th November 2006, 03:50 AM

And avoid any H32 tempers, I broke drill bits on a plate only 2.4mm thick

speaker · 13th November 2006, 06:40 PM

Quote:

Originally posted by Tom Bavis
I've used a metal angle under the transformers to strengthen it (you might be able to locate it so that the transformer bolts go through it).

Absolutely!

Metal angle works great with thin top plates. In the past I've run the angle stock directly under the transformers & near the power tube sockets. The top deck of the amplifier was rock solid. Below is a link for the OP for angle stock similar to I used. I bought something very close to it at Home Depot.

Aluminum Angle Stock

Geek · 14th November 2006, 12:24 AM

Quote:

Originally posted by speaker
Aluminum Angle Stock

Ouch!!

Check out a local welding shop. I pick up mine for 1/3 of that and in CAD.

speaker · 14th November 2006, 11:30 AM

Quote:

Originally posted by Geek

Ouch!!

Check out a local welding shop. I pick up mine for 1/3 of that and in CAD.

The above is an odd profile hence the price I'd think. The stuff I bought at Home Depot was even on both sides and cost a lot less. Around here the local welders work mainly in steel not alu.

kafka007 · 14th November 2006, 12:41 PM

Thank you all for your suggestions. Some clever bracing may be the right solution. I was looking at some .040-.078" thick brass before. I don't know if it will sag soo much under the weight of the transformers without the bracing. Looking at it the other way, I'm concerned about going too thick to use my Greenlee punches, so I have my doubts about using 1/8" thick material.

I'll definitely explore the aluminum angle suggestion. I imagine it wouldn't be needed anywhere there weren't a heavy object to support. Given the transformers I'm using, it looks like I won't need to make any big holes that would have to be cut through the angle stock. The alu should drill out pretty easily. If it's a tight fit into my wooden box, I might not even need to secure it to the sides to provide support.

11th November 2006, 08:43 PM	#1
kafka007 diyAudio Member Join Date: Nov 2006	Sheet Metal Gauge I'm building a fairly standard tube amplifier chassis using a sheet of brass screwed into a wooden frame. It'll be supporting 3 fairly heavy transformers (pwr + 2 opt), a choke, caps and of course the tubes. I was thinking of using brass. What gauge material do you recommend for such a top plate?

12th November 2006, 01:22 AM	#4
leadbelly diyAudio Member Join Date: Dec 2002 Location: Calgary, Alberta	You'll be good with 1/8" or 8 ga. sheet. __________________ Aerodynamics are for people who can't build engines. Enzo Ferrari

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Sheet metal cooling	Skorpio	Pass Labs	1	10th May 2008 12:49 PM
Metal dome should always go with metal cone? Is this a rule?	Jay_WJ	Multi-Way	5	5th February 2007 06:53 PM
Metal Oxide vs flamme proof vs metal film	ostie01	Parts	28	26th June 2006 06:38 AM
Construction: The best way to cut a hole for an IEC power inlet into sheet metal	PaulHilgeman	Parts	10	16th October 2003 08:36 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read

11th November 2006, 09:10 PM	#2
jayme diyAudio Member Join Date: Sep 2005	You could get some steel support rods or flat bars and make a support cross under the top plate. You wouldn't need much, and the extra support would make the brass gauge relatively moot. Also, if you could roll the edges on the brass, it would structurally re-enforce the load support. Cut a notch out of each corner and roll each long edge.

11th November 2006, 09:22 PM	#3
Tom Bavis diyAudio Member Join Date: Jun 2002 Location: Macedon NY	I've used a metal angle under the transformers to strengthen it (you might be able to locate it so that the transformer bolts go through it).

12th November 2006, 02:54 AM	#5
HollowState diyAudio Member Join Date: Aug 2006 Location: Taxland, New Jersey	A sheet of 1/8th inch brass will cost you a pretty penny to say the least. It will also tarnish easily unless you clear lacquer it. Why not use aluminum plate? It's just as functional and a lot less money. Just be sure to get a piece that's tempered. The most common is 6061-T6. (or T-351 or T-651) Tempered aluminum machines very nicely and is not gummy. Or use a piece of aluminum rack panel. I also prefer to support a standard chassis with aluminum right angle strips that I buy at Home Depot. (no affiliation) Victor

12th November 2006, 03:50 AM	#6
Geek diyAudio Member Join Date: Sep 2004	And avoid any H32 tempers, I broke drill bits on a plate only 2.4mm thick

14th November 2006, 12:41 PM	#10
kafka007 diyAudio Member Join Date: Nov 2006	Thank you all for your suggestions. Some clever bracing may be the right solution. I was looking at some .040-.078" thick brass before. I don't know if it will sag soo much under the weight of the transformers without the bracing. Looking at it the other way, I'm concerned about going too thick to use my Greenlee punches, so I have my doubts about using 1/8" thick material. I'll definitely explore the aluminum angle suggestion. I imagine it wouldn't be needed anywhere there weren't a heavy object to support. Given the transformers I'm using, it looks like I won't need to make any big holes that would have to be cut through the angle stock. The alu should drill out pretty easily. If it's a tight fit into my wooden box, I might not even need to secure it to the sides to provide support.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)