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

Chip Amps Amplifiers based on integrated circuits

Case idea to make you resin-ate
Case idea to make you resin-ate
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 19th September 2005, 12:58 PM   #1
Nordic is offline Nordic  South Africa
diyAudio Member
 
Nordic's Avatar
 
Join Date: Sep 2005
Default Case idea to make you resin-ate

Ok, while I'm waiting for the parts to arive, I am building and rebuilding this silly little 3875 amp over and over in my head... bet I can do it without the circuit diagrame by now...

Now as I had this whole amp constructed and suspended in space (in my mind) It reminded me of a clear casting-resin paperweight I made in primary school in class with components in...

So I was thinking, asuming I could make a jig/mold to encase the whole amp and all its components (except the powersupply) in a resin square... I could even do it so the bottom of the chip sits flush with a side so it could still screw into a powersupply

Do you think it could work, in terms of dissapating heat, so that the resin would sorta act like a big heatsink, drawing the heat out evenly, and provide a larger surface area for cooling of.

or do you think it will end up as another paperweight.

we are talking about a unit here that will not be repairable...if it breaks, its a paperwieght.
  Reply With Quote
Old 19th September 2005, 03:03 PM   #2
owen is offline owen  United Kingdom
diyAudio Member
 
Join Date: Mar 2004
Location: Shilton
I cant see a significant reason why you shouldn't do this.

The chips will need heatsinks. Use the heatsinks to form the 2 sides - have the chips mountedto the heatsinks before you begin.

Then using some sheet acrylic, make a u shape that will form the mould. Secure on the outside using some hot melt glue.

Now is the tricky bit - suspend the power supply jacks, the RCA inputs and the speaker outputs from a jury rigged frame, at the final level of the back of the amp. Fill the mould with resin to the finished level on the back, and wait for setting.

carefully peel the mould from your unique crystal gainclone...

Do let us see the finished product!

Owen
  Reply With Quote
Old 20th September 2005, 02:33 PM   #3
elementx is offline elementx  United States
diyAudio Member
 
elementx's Avatar
 
Join Date: Jul 2005
Location: Cleveland OH
I would like to see that! Just curious, what kind of "resin" do you use? Can you give me any brands or webpages that have that stuff? I know exactly what you're talking about, but I have never come across it in a store. thanks!
  Reply With Quote
Old 20th September 2005, 03:42 PM   #4
Nordic is offline Nordic  South Africa
diyAudio Member
 
Nordic's Avatar
 
Join Date: Sep 2005
Just google for Clear casting resin, the stuff looks like glass when you are done... Oh you get dyes too.. so you could have clear, blue, red, amber etc... You also get opage resin, but I can't see why you'd want to use that.

Ok got most of the parts, and a few weak substitutes, hope to have it all working in a day or so....

Would still be a little while before I do the casting though, as I need to get some better parts from overseas
  Reply With Quote
Old 20th September 2005, 03:58 PM   #5
analog_sa is online now analog_sa  Europe
diyAudio Member
 
analog_sa's Avatar
 
Join Date: Aug 2002
Location: Cascais
Case idea to make you resin-ate
HI Nordic

Careful with the resin. Around 1980 i sold a few MC step-ups based on LM394 (not that it matters). Due to extreme idiotism and paranoia i poured some epoxy on top and bottom of the PCB in an attempt to make reverse engineering impossible. Once the epoxy set and i powered it up i had a shock. The sound was practically unlistenable. Don't know if it was a change in dielectric absorption due to impurities in the epoxy but it certainly thought me a lesson. Those 394s were not cheap.

Even if DA is not an issue the dramatic change in structural rigidity and damping will have quite an effect on sound.


One thing a chipamp does not need is improving the heat dissipation.
  Reply With Quote
Old 20th September 2005, 04:39 PM   #6
elementx is offline elementx  United States
diyAudio Member
 
elementx's Avatar
 
Join Date: Jul 2005
Location: Cleveland OH
Quote:
Originally posted by analog_sa
HI Nordic

Careful with the resin. Around 1980 i sold a few MC step-ups based on LM394 (not that it matters)....Once the epoxy set and i powered it up i had a shock. The sound was practically unlistenable.
So this was in 1980's? Do you think there has been an improvement in the resin to this date? I think that would be so cool to have your amp enclosed in a resin cube, or sphere even! Maybe it's worth trying. Even as a paper-weight it would look pretty cool!
  Reply With Quote
Old 20th September 2005, 04:58 PM   #7
dnsey is offline dnsey  United Kingdom
diyAudio Member
 
Join Date: Mar 2004
Location: Shropshire, England
If I remember correctly, casting resin cures a little cocave and tacky on the 'open' face, so you will need to arrange things so that this face can be filed and sanded flat.
  Reply With Quote
Old 20th September 2005, 05:31 PM   #8
tvi is offline tvi  Australia
diyAudio Member
 
tvi's Avatar
 
Join Date: Apr 2001
Location: Moonee Ponds, Vic, Australia
Should match with this Ice cube CD player
/www.monoone.com

Regards
James
Attached Images
File Type: jpg 25267.jpg (81.0 KB, 467 views)
  Reply With Quote
Old 20th September 2005, 06:06 PM   #9
Nordic is offline Nordic  South Africa
diyAudio Member
 
Nordic's Avatar
 
Join Date: Sep 2005
Yeah, I believe, there are quick setting resins on the market now, but last time I did this, the resin had to sit a good few days to crystalise properly, and then the hard part starts, sanding it all down....
  Reply With Quote
Old 20th September 2005, 06:19 PM   #10
rif is offline rif  United States
Neither a cowbow nor dog owner
diyAudio Member
 
rif's Avatar
 
Join Date: Jan 2003
Location: Southern NJ
Case idea to make you resin-ate
What about this stuff:

http://www.leevalley.com/wood/page.a...at=1,190,42942
  Reply With Quote

Reply


Case idea to make you resin-ateHide 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
How small can I make a case for a LM3875 kit? m0b1liz3 Chip Amps 9 3rd July 2008 11:10 PM
New idea: Make a thick ribbon thinner APi Planars & Exotics 1 8th August 2005 02:23 PM


New To Site? Need Help?

All times are GMT. The time now is 10:37 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki