Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => AmpTools/Tech Tips => Topic started by: fdesalvo on January 11, 2009, 07:04:37 pm

Title: pics of my new bare tr chassis- questions: defects?
Post by: fdesalvo on January 11, 2009, 07:04:37 pm

Inside of my chassis, there are some raised spots around the pot holes.  What's the best thing to use to levl this so my pots aren't crooked? 

Edit: see pics below

Title: Re: best tool to smooth rough edges in aluminum
Post by: tubesornothing on January 11, 2009, 07:46:43 pm

Its called a "deburring tool" or you could (sort of) use a counter sink.  kbctools.com, among others.

Title: Re: best tool to smooth rough edges in aluminum
Post by: jhadhar65 on January 11, 2009, 09:46:00 pm

Take a drill bit in hand that's a couple of sizes bigger than the hole.  Give it a few twists and viola!  Remember to just hold it in your hand - no drills or screw guns.  Makes short work of it.

Title: Re: best tool to smooth rough edges in aluminum
Post by: fdesalvo on January 11, 2009, 11:00:43 pm

I appreciate the answers. guys.  I am going to post some pics so you can see what I'm talking about- it's on the inner side o my twin chassis, so I can't fit a conventional tool in there.  Please see below and advise if I need to make some changes.

The outside is powdercoated and some of the overspray hit the inside of the control holes.  Additionally, you will notice they are countersunk to "allow the face of the pot to make better contact with the chassis..."  ::)

(http://i443.photobucket.com/albums/qq151/frank_desalvo/IMG_0358.jpg)

I've used a conical grinding bit to grind away as much of the overspray to ensure a good mechanical ground connection, but I'm not sure if I did enough.  It's difficult as hell.  You'll see that the "burr" is actually a raised ring of material left by the manufacturer.  If worse comes to worse, I'll just run the pot/input buss into a bolt below the input- that way I know I have a solid ground for the preamp/pot/input buss.

Title: Re: pics of my new bare tr chassis- questions: defects?
Post by: JayB on January 14, 2009, 03:04:18 pm

Something like this works for tight places for a fast deburring. Or, it's dremmel time.


http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92188

Title: Re: pics of my new bare tr chassis- questions: defects?
Post by: fdesalvo on January 15, 2009, 01:37:43 pm

Thanks, dude- as it turns out- it wasn't a bur bt an intentional lip carved into the inside eedge.  It's actually genius- the pots fully contact the chassis.