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

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

torque on silca pads
torque on silca 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
Reply
 
Thread Tools Search this Thread
Old 13th January 2018, 08:24 PM   #1
MaccAu is offline MaccAu  Australia
diyAudio Member
 
MaccAu's Avatar
 
Join Date: Sep 2009
Location: Gold Coast - Australia
Send a message via AIM to MaccAu Send a message via MSN to MaccAu Send a message via Yahoo to MaccAu torque on silca pads
Default torque on silca pads

What is the best torque for applying to the silpads? for the following. I dont have a torque set but maybe i can get away without or get one if needed

Re: torque on SPK4-0.006-00-58 - for Thyristor to heatsink?
Tensile Strength 5000 psi

Re torque on SP900S-0.009-00-105 - for Sanken Output transistors on an amplifer - shape of the sanken output transistors 200w MT200
Tensile Strength:1300 psi

Sam

Mouser Parts links (digikey has actual photo of item) for Sanken
SP900S-0.009-00-105 Bergquist | Fans, Thermal Management | DigiKey
__________________
1980s are rad

Last edited by MaccAu; 13th January 2018 at 08:39 PM.
  Reply With Quote
Old 13th January 2018, 08:41 PM   #2
JonSnell Electronic is offline JonSnell Electronic  United Kingdom
diyAudio Member
 
JonSnell Electronic's Avatar
 
Join Date: Dec 2012
Location: The Jurassic Coast, England. GB
Hand tight is the norm. Depends on the nut/bolt type. If steel more torque than brass but if silicon heat sink compound is used, hand tight is fine.
Have a look at the chart;
https://mdmetric.com/tech/Standard_t...ing_torque.pdf

Hope that helps.
__________________
Support for Fender, Marshall and all Valve Equipment; Audio Innovations, Audiorama FU29, Quad and Leak. www.jonsnell.co.uk
  Reply With Quote
Old 13th January 2018, 09:54 PM   #3
Elvee is offline Elvee  Belgium
diyAudio Member
 
Elvee's Avatar
 
Join Date: Sep 2006
Since this one is fiber-glass reinforced, it has no practical limit by itself, but the object you want to cool certainly has, especially if it is partly or totally made of plastic (remember though that even full-metal parts also have a limit)
__________________
. .Circlophone your life !!!! . .
♫♪ My little cheap Circlophoneİ ♫♪
  Reply With Quote
Old 13th January 2018, 10:12 PM   #4
scottjoplin is offline scottjoplin  Wales
diyAudio Member
 
scottjoplin's Avatar
 
Join Date: Dec 2015
Location: Penrhyndeudraeth
Use these to allow for expansion and contraction Belleville washer - Wikipedia
__________________
Woofer Assisted Wideband is the New Testament renounce the anachronistic acronym FAST
  Reply With Quote
Old 13th January 2018, 10:24 PM   #5
multi-volti is offline multi-volti  United States
diyAudio Member
 
multi-volti's Avatar
 
Join Date: May 2005
Location: Michigan
Old Motorola (obviously old) semiconductor databooks used to have app notes discussing things like heatsink mounting surface flatness (25-50 micro-inch iirc) and hardware torque for different packages. 6-32 screws on a TO-220 package probably had only a single-digit-to-low-double-digit torque (#-inch) need (wild guess 6-12 oz.-inches?). The flatness and grease or silpad assure no air gap so there is good heat transfer/low thermal resistance. Tensile strength probably relates to limits on the screws...shouldn’t be approaching any failure limits...finding semiconductor mounting requirements would probably be more meaningful than limits associated with failure. The heatsink flatness probably assured the bulk of the work for good heat transfer. There was probably no pressure spec for thermal compound used before pads because the flatness made it happen.

I also remember hole diameter recommendations for mounting screws to avoid deforming the semiconductor surface into the hole, causing potential die damage inside the device package.
__________________
Murray
  Reply With Quote
Old 15th January 2018, 11:10 PM   #6
llwhtt is offline llwhtt  United States
diyAudio Member
 
Join Date: Jun 2008
Location: SoCal
Motorola AN-1040 has all of the mounting specs for different transistor case types, TO-3 is 6 in/lbs and TO-220 is 8 in/lbs. It also has specs for different insulator types, mica, silpad, etc.

Craig
  Reply With Quote
Old 16th January 2018, 02:35 AM   #7
multi-volti is offline multi-volti  United States
diyAudio Member
 
multi-volti's Avatar
 
Join Date: May 2005
Location: Michigan
Cool- Thanks, Craig...I had my units pretty mixed up...started to get nervous thinking pounds vs inches & flinched...chose ounces...oops
__________________
Murray
  Reply With Quote
Old 16th January 2018, 11:52 PM   #8
llwhtt is offline llwhtt  United States
diyAudio Member
 
Join Date: Jun 2008
Location: SoCal
I didn't notice your torque specs, I was just adding the document # that shows all of that data. AN1040 shows in/lbs, my torque driver is in in/lbs but the guys on the other side of the pond want it to be lb/ins which is probably more correct.

Craig
  Reply With Quote
Old Today, 10:02 AM   #9
Kay Pirinha is offline Kay Pirinha  Germany
diyAudio Member
 
Join Date: Oct 2011
Location: Somewhere in Germany
Quote:
Originally Posted by llwhtt View Post
I didn't notice your torque specs, I was just adding the document # that shows all of that data. AN1040 shows in/lbs, my torque driver is in in/lbs but the guys on the other side of the pond want it to be lb/ins which is probably more correct.

Craig


What the hell is this? Torque is defined as the product of force times lenght, not as a division!


Best regards!
__________________
"Bless you, Sister. May all your sons be bishops." (Brendan Behan)
  Reply With Quote

Reply


torque on silca 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
Max torque for M4 bolt into 8mm Aluminium triplej Construction Tips 13 18th January 2014 01:28 PM
high torque ac motor recommendations loheswaran Analogue Source 0 18th November 2012 08:40 AM
Torque Bass Amp T100 1EB Need Transistor Trev666 Vendor's Bazaar 2 14th June 2012 02:46 PM
Please Recommend a Torque Screwdriver Seraph Everything Else 12 17th August 2008 01:42 PM


New To Site? Need Help?

All times are GMT. The time now is 12:06 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki