Welcome To the Hoffman Amplifiers Forum

September 08, 2025, 03:42:06 pm
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Isolate terminal ground lugs from chassis?  (Read 2052 times)

0 Members and 1 Guest are viewing this topic.

Offline jonathan_kea

  • Level 1
  • *
  • Posts: 73
  • I love Tube amps
Hoffman Amps Forum image
Isolate terminal ground lugs from chassis?
« on: July 18, 2020, 09:31:52 am »
Now that I’ve got it working, I want to make some changes to the layout on my 5C1 build.

I’m working with a six lug terminal strip in the power supply and want to bring the 6v6 cathode resistor over so it can share a common ground with the filter caps.

The only problem is that I am out of lugs. Is there a proven way to lift the two outer ground lug connections off the chassis so they can accept positive voltage? I’m thinking about using nylon washers - has anyone attempted this before?

Offline Latole

  • Level 4
  • *****
  • Posts: 2522
Hoffman Amps Forum image
Re: Isolate terminal ground lugs from chassis?
« Reply #1 on: July 18, 2020, 09:58:04 am »
I don't know what you mean "....using nylon washer."

Post picture of your wiring.

I use that kind of terminal strips: Vintage parts.

https://www.tubesandmore.com/products/terminal-strip-5-lug-1st-lug-common-horizontal-package-5


 
« Last Edit: July 18, 2020, 10:00:29 am by Latole »

Offline vampwizzard

  • Level 3
  • ***
  • Posts: 501
  • Don't let the magic smoke out of the machines
    • Walbertedwards.com
Hoffman Amps Forum image
Re: Isolate terminal ground lugs from chassis?
« Reply #2 on: July 18, 2020, 10:00:26 am »
You'd have to isolate the terminal thats hitting ground as well as isolate the fastener from terminal.. i.e. youll need to use a nylon screw. Id look for other options.

Offline shooter

  • Level 5
  • *******
  • Posts: 11018
  • Karma Loves haters
Hoffman Amps Forum image
Re: Isolate terminal ground lugs from chassis?
« Reply #3 on: July 18, 2020, 10:01:26 am »
Quote
I’m thinking about using nylon washers

grab nylon screws and nuts while you're at it, otherwise you just make it taller  :icon_biggrin:
Went Class C for efficiency

Offline jonathan_kea

  • Level 1
  • *
  • Posts: 73
  • I love Tube amps
Hoffman Amps Forum image
Re: Isolate terminal ground lugs from chassis?
« Reply #4 on: July 18, 2020, 10:15:22 am »
Excellent point on the screw and washer! I would have use a metal screw and nut, totally defeating the purpose and probably catching my house on fire.

Latole - Will check into those horizontal terminal strips too. Might be a better fit. Thanks all!

Offline sluckey

  • Level 5
  • *******
  • Posts: 5075
    • Sluckey Amps
Hoffman Amps Forum image
Re: Isolate terminal ground lugs from chassis?
« Reply #5 on: July 18, 2020, 11:12:45 am »
Is there a proven way to lift the two outer ground lug connections off the chassis so they can accept positive voltage?
Bad idea. Don't do it.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline jonathan_kea

  • Level 1
  • *
  • Posts: 73
  • I love Tube amps
Hoffman Amps Forum image
Re: Isolate terminal ground lugs from chassis?
« Reply #6 on: July 18, 2020, 12:36:29 pm »
Agreed. Going to use an extra strip.

 


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