Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Swap Meet Sell your stuff here, who knows, some other fanatic might be interested!

Wanted TO-247 Beryllium Oxide pads
Wanted TO-247 Beryllium Oxide pads
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
Closed Thread
Thread Tools Search this Thread
Old 28th June 2002, 06:28 PM   #1
dshortt9 is offline dshortt9  United States
diyAudio Member
dshortt9's Avatar
Join Date: Apr 2001
Location: Milwaukee, Wisconsin
Default Wanted TO-247 Beryllium Oxide pads

I would like about 25 for a Pass Aleph 2 project.
Old 28th June 2002, 10:55 PM   #2
P.Lacombe is offline P.Lacombe  France
diyAudio Member
Join Date: Jul 2001
Location: Orleans, France
Don't make pollution worse ! Beryllium Oxide is very toxic.
Use mica pads, with a little silicon grease. Works very fine.

Regards, P.Lacombe.
Old 29th June 2002, 02:44 AM   #3
cocolino is offline cocolino  Germany
diyAudio Member
cocolino's Avatar
Join Date: May 2002
Location: Bavaria (south of veal sausage equator)
Use mica pads, with a little silicon grease. Works very fine.
Or even somewhat better regarding termic conductivity: Kapton pads
Old 29th June 2002, 07:23 AM   #4
AudioFreak is offline AudioFreak  Australia
Warp Engineer
On Holiday
AudioFreak's Avatar
Join Date: Oct 2001
Location: Queensland, Australia
Wanted TO-247 Beryllium Oxide pads
I dont feel like an argument here but when all things are considered, mica is the best for TO-247/TO-3P devices.
Old 29th June 2002, 02:11 PM   #5
grataku is offline grataku  United States
diyAudio Member
Join Date: Dec 2000
Location: -
are you building a nuclear reactor or an amp?
If it was thermally conductive, would you use something like asbestos for your transistor pads? BeO has pretty much the same effects on your health as asbestos.
Before you use funky materials in your stereo take a look at their material safety data sheet (MSDS), they are all over the web.
Old 29th June 2002, 07:44 PM   #6
P.Lacombe is offline P.Lacombe  France
diyAudio Member
Join Date: Jul 2001
Location: Orleans, France

The most important : surfaces and isolating pad must be perfectly plane and surgically clean. Use pure silicon grease, not compound which is too pasty. Mica or Kapton works well...

Regards, P.Lacombe
Old 29th June 2002, 08:23 PM   #7
dshortt9 is offline dshortt9  United States
diyAudio Member
dshortt9's Avatar
Join Date: Apr 2001
Location: Milwaukee, Wisconsin

OK, I may be overdoing it. I'll stick with mica. I work in a factory that made machined beryllium parts for the space program and also have worked for the worlds largest supplier of rare earth and inorganic chemicals so I'm well aware of the hazards of beryllia. BUT, Thanks for the warning anyway. I'm sure the majority of people are unaware of the dangers involved.
Old 1st July 2002, 05:55 PM   #8
Peter Daniel is offline Peter Daniel  Canada
diyAudio Member
Peter Daniel's Avatar
Join Date: Jul 2002
Location: Toronto, Canada
Wanted TO-247 Beryllium Oxide pads Send a message via AIM to Peter Daniel
I was under the impression that BO pads were the best around and that's why I'm using them exlusively. When handled properly I don't think they create much danger, at least I wouldn't compare them to asbestos which has totally different material structure (they still use asbestos in aerospace industry).
I like that Forum, because I'm always learning something new.
Old 1st July 2002, 06:18 PM   #9
Claus is offline Claus  Denmark
diyAudio Member
Join Date: Feb 2001
Location: Denmark / Germany
You should not use Beryllium Oxide at all.

Extremely toxic by inhalation and ingestion. Typical LD50s for beryllium compounds are between 0.5 and 5 mg/kg. Probable human carcinogen. Serious respiratory irritant. May be harmful by skin contact.

KCN (Potassium Cyanide)
LD50 oral 5 mg/kg

"The Lethal Dose 50 (LD50) test involves the administration of a substance to a group of animals at increasing doses in order to determine the dose that kills 50 percent of the test subjects within a set time frame."

Get my drift.

Old 1st July 2002, 06:21 PM   #10
sam9 is offline sam9  United States
diyAudio Member
sam9's Avatar
Join Date: Jun 2002
Location: Left Coast
Default sam9

I used to work for company that used Beryllium Oxide. Yes, it's dangerous and probably not for the DIYer, but it isn't the work of the devil either. We complied with OSHA and EPA in using it. A solid piece of it is pretty harmless. You can touch it it without fear if it is clean, as in dust free. Its a ceramic and the danger comes if you break it. That releases ihaleable ingestible dust. Worse is if you cut it - lots of dust. Obviously, using in in fabrication requires precautions and ways of containing the dust. Not diffucult in a production situation. Not practicle in your garage.

Once included in the final assembly of a product its inert. Later disposal is a problem because breaking, cutting or crushing release dust from it. I don't recall for sure, but I don't think burial was a problem since it doesn't tend to leach out - just sit where you left it.

In short not something to mess with, but certainly far from being in the same category as nuclear waste.

That was 10+ years ago, so maybe more is known now.

Closed Thread

Wanted TO-247 Beryllium Oxide padsHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
beryllium ScanSpeak and other new goodies stuman Multi-Way 8 24th April 2009 09:57 PM
Beryllium Tweeter kevinlomax Multi-Way 12 19th February 2005 09:51 PM
Beryllium Oxide Question psychokids Solid State 11 27th December 2004 05:18 PM
Aluminum oxide insualtion pads for TO-247 Peter Daniel Swap Meet 21 15th July 2003 03:06 PM

New To Site? Need Help?

All times are GMT. The time now is 12:23 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio