Welcome To the Hoffman Amplifiers Forum

September 06, 2025, 05:17:52 pm
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Galvanized chassis  (Read 5431 times)

0 Members and 1 Guest are viewing this topic.

Offline Bub

  • Level 2
  • **
  • Posts: 166
Hoffman Amps Forum image
Galvanized chassis
« on: November 02, 2010, 09:39:31 pm »
Hi Gent's,

Is there any reason not to use galvanized steel when building a chassis.

Thanks

Rob

Offline dynaman1

  • SMG
  • Level 2
  • *****
  • Posts: 120
Hoffman Amps Forum image
Re: Galvanized chassis
« Reply #1 on: November 02, 2010, 09:56:57 pm »
Not that I know of, but I'd grind to untreated bare metal for your ground and earth connections.

Offline Bub

  • Level 2
  • **
  • Posts: 166
Hoffman Amps Forum image
Re: Galvanized chassis
« Reply #2 on: November 02, 2010, 10:05:42 pm »
Thanks dynaman 1,

Great tip. I would have never thought of that.

Rob


Offline eleventeen

  • Level 4
  • *****
  • Posts: 2229
Hoffman Amps Forum image
Re: Galvanized chassis
« Reply #3 on: November 03, 2010, 12:34:34 am »
Ummm, there are several different types of galvanized. There is "hot dip", which will leave a much thicker layer of galv metal on the steel, often with small inclusions and irregularities in it which could cause problems if you need to achieve a nice finish somewhere. I'm not sure what the other types of galvanized are called, if anything. Other than what I said in the first sentence, I don't see any electrical reason why it would be a problem.

And also, there is the issue of whether the raw sheet metal was galv'ed and then bent, or, the already-bent chassis was galv'ed. I could see galvanizing flake off if it was raw (flat) sheet steel that was later bent around a curve.

Offline Bub

  • Level 2
  • **
  • Posts: 166
Hoffman Amps Forum image
Re: Galvanized chassis
« Reply #4 on: November 03, 2010, 12:49:36 am »
I think I'll skip the galvanized and buy a plain sheet. A friend of mine has a skid of 18 ga galvanized sheet so free was better but I only have one chance to build the chassis.

Thanks

Rob

Offline kagliostro

  • Level 5
  • *******
  • Posts: 7739
Hoffman Amps Forum image
Re: Galvanized chassis
« Reply #5 on: November 03, 2010, 05:11:57 am »
Galvanized chassis

galvanized with which metal ?

Kagliostro
The world is a nice place if there is health and there are friends

Offline supro66

  • Level 3
  • ***
  • Posts: 525
  • I love tube amps
Hoffman Amps Forum image
Re: Galvanized chassis
« Reply #6 on: November 03, 2010, 05:32:38 am »
I built my first one that way
Homedepot heating duct and angles







Doug sells the lugs drill hole attack a lug and you have a good solder point

Then I used leather contact paper

YES ALL SUPRO'S HAD THREE PIECES OF WOOD IN THEM



It plays well
« Last Edit: November 03, 2010, 05:37:02 am by supro66 »

Offline stingray_65

  • SMG
  • Level 3
  • *****
  • Posts: 926
Hoffman Amps Forum image
Re: Galvanized chassis
« Reply #7 on: November 03, 2010, 06:57:01 am »
Galvanized chassis

galvanized with which metal ?

Kagliostro

Zinc

Galvanized steel is for use outdoors or where corrosion would be a problem. the zinc oxidizes and creates an inert, protective layer.

Galvanized sheet metal is designed to be bent on a brake without flaking. you should however increase the bend radius by 50% to avoid the flaking. So if for example your 18ga material. cold rolled 18ga sheet would have a bend radius of 3/64" your galvanized 18 ga would be about 5/64" (a little more than 1/16).

(Bend radius is measured inside the bend)

The issue with Galvanized steel is cosmetic, Paint does not stick well to it, even paint designed for it. The protective layer I mentioned before will form and paint will peel. Left raw it forms a mottled chalky grey color.

Dyna is correct in suggesting to get to the base material on ground points. Grinding sounds excessive, 100 grit sand paper and some firm thumb pressure will get you there quickly. You will see it clearly when you get there.

IF you decide to tack weld corners, be aware that the gasses given off are hazardous.

Ray
« Last Edit: November 03, 2010, 07:00:51 am by stingray_65 »
My mind is aglow with whirling, transient nodes of thought careening through a cosmic vapor of invention (H. Lamarr)

 


Choose a link from the
Hoffman Amplifiers parts catalog
Mobile Device
Catalog Link
Yard Sale
Discontinued
Misc. Hardware
What's New Board Building
 Parts
Amp trim
Handles
Lamps
Diodes
Hoffman Turret
 Boards
Channel
Switching
Resistors Fender Eyelet
 Boards
Screws/Nuts
Washers
Jacks/Plugs
Connectors
Misc Eyelet
Boards
Tools
Capacitors Custom Boards
Tubes
Valves
Pots
Knobs
Fuses/Cords Chassis
Tube
Sockets
Switches Wire
Cable


Handy Links
Tube Amp Library
Tube Amp
Schematics library
Design a custom Eyelet or
Turret Board
DIY Layout Creator
File analyzer program
DIY Layout Creator
File library
Transformer Wiring
Diagrams
Hoffmanamps
Facebook page
Hoffman Amplifiers
Discount Program


password