easier way to cut a square hole for xmfr - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 24th March 2008, 10:29 PM   #1
PRNDL is offline PRNDL  United States
diyAudio Member
 
Join Date: Oct 2006
Default easier way to cut a square hole for xmfr

I'm considering building another amp, and am wondering what the easiest way is to make a square hole for the power transformer.

The last time I used a jigsaw followed by filing the edges to fit. It wasn't hard, but took time and was fairly annoying.

Is there another method that is easier than the jigsaw and file?

Any recommendations are appreciated.
  Reply With Quote
Old 24th March 2008, 10:45 PM   #2
diyAudio Member
 
Join Date: Mar 2008
It's one of those jobs I don't like either.

One other way is to use a nibbling tool, but that can take a while for a big transformer.

Another crude method is to drill a series of small closely spaced holes around the perimeter of the desired rectangular hole, then cut between the holes with a cold chisel, then file.
  Reply With Quote
Old 24th March 2008, 11:20 PM   #3
Jeb-D. is offline Jeb-D.  United States
diyAudio Member
 
Jeb-D.'s Avatar
 
Join Date: Nov 2005
Location: SoCal
I gave up doing my own metalwork and now just use www.frontpanelexpress.com
  Reply With Quote
Old 25th March 2008, 12:04 AM   #4
diyAudio Member
 
benchtester's Avatar
 
Join Date: Apr 2007
Location: Oakland, Calif.
I am not sure of the material you are trying to cut, but for wood or aluminum you can use a router with a carbide burr or end mill, maybe 1/8" in diameter. Make a wood frame to guide the router to the square pattern. Make sure that the material is well attached or clamped to the frame, since the cutter may want to grab the material. Afterward, you will have 1/16" radius in the corners, which you can leave or clean up with a file.
  Reply With Quote
Old 25th March 2008, 12:56 AM   #5
diyAudio Member
 
Join Date: Mar 2008
That's it, time I bought a router.
  Reply With Quote
Old 25th March 2008, 01:17 AM   #6
diyAudio Member
 
zigzagflux's Avatar
 
Join Date: Oct 2006
Location: Charlotte, NC
2nd vote for frontpanelexpress.

Never again will I cut my own. My time is too valuable. A $130 perfect panel just can't be beat.
  Reply With Quote
Old 25th March 2008, 01:23 AM   #7
diyAudio Member
 
Join Date: Aug 2006
I'm way too much of a tightwad to spend $130 on a panel.

A while back I had to do some duct work. Decided there had to be a better way to cut a round hole into the side of a duct in a confined space. There is! Make a square one with a dremel tool and a cutoff disc. Not hard to get nice straight lines. Don't try to go too fast or put any lateral pressure on the disc. Even the slightest lateral pressure will break the disc. This isn't a big deal provided you're wearing safety glasses. The discs come in mutlipack at your local hardware store.
  Reply With Quote
Old 25th March 2008, 12:08 PM   #8
PRNDL is offline PRNDL  United States
diyAudio Member
 
Join Date: Oct 2006
It's aluminum.

I may use a router or rotozip to do this, but was wondering about it.
  Reply With Quote
Old 25th March 2008, 12:28 PM   #9
Sherman is offline Sherman  United States
diyAudio Member
 
Join Date: Feb 2004
Location: Chicago area
Depending on the thickness of the metal you may be able to use a 'nibbler'. This is a tool that cuts rectangular holes by cutting out little rectangles of metal. It has handles like pliers that you squeeze together. Advantages- cheap ($10 US), easy to use. Disadvantages- big holes can make your hand tired!

I use them in thinner chassis for square holes for things like IEC inlets.
__________________
--Sherman
  Reply With Quote
Old 25th March 2008, 01:36 PM   #10
diyAudio Member
 
Ty_Bower's Avatar
 
Join Date: Mar 2007
Location: Newark, DE
Quote:
Originally posted by CarlyBoy
Make a square one with a dremel tool and a cutoff disc. Not hard to get nice straight lines. Don't try to go too fast or put any lateral pressure on the disc. Even the slightest lateral pressure will break the disc. This isn't a big deal provided you're wearing safety glasses. The discs come in mutlipack at your local hardware store.
I made the hole for the PT on this chassis using a Dremel with the cutoff wheels. It came out looking real nice, but took forever. The aluminum is 1/8" thick. I must have gone through at least two or three discs on each side of the hole. Definitely buy the cutoff wheels in the biggest pack they sell (25?). Go for the "heavy duty" ones, too. I wouldn't even dream of attempting this on a steel chassis.

Click the image to open in full size. Click the image to open in full size.

I've been told the Gyro brand cutoff wheels are about 100 times better than the Dremel. You can find them here:
http://www.gyrostools.com
# 11-32156 and grab their mandrel model # 80-1800
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Circuit simulation on Linux just became a bit easier tcpip Solid State 29 10th November 2013 06:55 PM
Wire frames...is there an easier way? Spasticteapot Planars & Exotics 7 19th January 2007 02:42 AM
Easier AlephX...Can you diy it ? aht Pass Labs 4 14th January 2005 04:04 AM
LM741-Is there an easier or better way? Bose(o) Solid State 7 21st April 2004 10:56 AM


New To Site? Need Help?

All times are GMT. The time now is 01:53 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2