Hand-made aluminum heatsinks

vdi_nenna

Member
Paid Member
2000-10-10 7:27 pm
PA, USA
Hi everybody,

My brother Lou and I finished a set of heatsinks. They are 2"x6"x15" each in dimension, with about 48 fins per sink. I have pictures of them and I'm going to put them up on my site soon.

Some background on them...
All the parts are milled, not saw cut. Fins and seperators were cut to about 3-4 thousandths of of an inch for tight tolerance. All part were polished and de-burred (no sharp edges). All the holes were drilled close for 1/4-20 rods, so there is very little play.

Once you see the work and if anyone is interested in having this kind of work done, email me from this site. We can make them to your specs.

Vince
 

vdi_nenna

Member
Paid Member
2000-10-10 7:27 pm
PA, USA
All Thumbs...

I'm going to try to use Photo Shop tomorrow night and make the pix smaller for faster up and downloading of pages. They are too damn big right now, and I'm real fired up about the whole thing, that's why only the thumbs right now. I can't wait to show them. Pretty nice work by my bro!



(It's ready)

http://homestead.juno.com/vincenet3/Homepage.html

[Edited by vdi_nenna on 03-22-2001 at 12:10 AM]
 

vdi_nenna

Member
Paid Member
2000-10-10 7:27 pm
PA, USA
What do you think??

So...how do they look now?? I think this design makes it easy to put on a front and back plate. Now if I could just start on that new amp project!!

BTW- Thanks for the advice on the pix Petter, they were already in a jpeg format. The pictures were 1600x1400, I [email protected] each! In Adobe Photo Shop they were 4.5 megs (.ppd or .pdd)! I cropped them and resized them close to 800x600. Then converted back to jpeg. It worked nicely. Thanks!

Vince

http://homestead.juno.com/vincenet3/Homepage.html
 

Jason

Powder Monkey
Paid Member
2000-10-08 1:19 pm
Melbourne
www.diyaudio.com
The pictures look great... I've always been a fan of nice clean pictures (with a reasonable size!) and quick loading thumbnails ;)

As far as web design advice goes, i don't know how much you can really do when you're using a free homepage creator - might I suggest downloading an evaluation of dreamweaver from macromedia, nothing comes close IMHO and it's basically WYSIWYG ;)

http://www.macromedia.com/software/dreamweaver/download/

I would love to hear a justification for the splash page though ;)
 

vdi_nenna

Member
Paid Member
2000-10-10 7:27 pm
PA, USA
Jason, Do you mean the first enterance page? Well, the counters aren't really good, so I thought that having a home page then entering the index section would lower the occurance for bogus hits. 'Cause everytime you go back to the first page, it's a hit, right? Plus, I look at web pages sort of like a book, that would be the (soft)cover. :)

ps. thanks for the input!!

[Edited by vdi_nenna on 03-22-2001 at 10:07 AM]
 

Jason

Powder Monkey
Paid Member
2000-10-08 1:19 pm
Melbourne
www.diyaudio.com
Yes the front door page, or 'splash' page :) What are you trying to measure? Unique visitors? These will be in your web statistics (does your host provide statistics?).

This might go over your head but if you really wanted to hack it you could open up a two frames, one with the counter in it and the other with your site in it. That would fairly accurately measure the number of unique visitors you're getting, but then you would need to add target="_top" to all your external links (to break out of the frames).
 

vdi_nenna

Member
Paid Member
2000-10-10 7:27 pm
PA, USA
Heat transfer and Attaching Transistors...

...I guess these two go hand in hand. I was planning on trying to attach the trans. directly to the heatsink. But, I don't think this is the best way, because no matter how straight and perfectly lined up the pieces are, you still get gaps.

A way around this is to attach a solid rod across all the fins and seperators, or an L-bracket. But first, add liberal amounts of silicon grease to the rod or L-bracket. Then, attach the trans. to the rod or L-bracket. This will also give you slight more surface area.

Lou tells me that Aluminum is dirty. I guess he means when working with it it get diry because of the cutting grease. He said to use 2 part water and one part clear vinegar to clean the parts (if milled).

On this site, look under Amplifiers> Construction> Massive Class A Heatsinks. The plans are nice. The guy who set it up is a nice guy, very helpful too.

I decided to try this because I'm tired of looking for large heatsinks. This method allows me to have 2 sides of the case already finished and provides an easy way to attach a front and back panel.

I'm going to assemble these sinks around my Zen amp, that runs on two amps right now. I'm going to rise that to 3 amps. I did some basic calculations and they are more then enough for that design. When I'm done, I'll put the whole thing on my site.

Does anyone know the proper way to take case temps from a trans.??

Vince

ps, they were not milled flat after assembly. They are however very flat just by quickly putting them together, as they are in the pictures. I could probably get a flatter surface by making minor adjustments and then torquing the ends. My brother says there is a adhesive that can be applied to the end where the bolts are attached. He said that high temps don't effect the adhesive. The aluminum would melt before the adhesive does. His words, not mine...

[Edited by vdi_nenna on 03-23-2001 at 01:39 PM]
 
Remember to not use Fe

For rods and nuts, please consider not using anything with Iron, and if you do, check that it is not magnetizable (you get stainless in magnetizable and un-magnetizable). Parts with iron in them are not recommended at all. Brass is a much better alternative if it is strong enough for you.

Most cases are made of steel, but steel is crap. Use aluminum or better still copper since Aluminum does not have perfect magnetic properties either (it is in fact paramagnetic)

Goint into a detailed discussion on magnetism is beyond my scope of expertise, but Iron content is certainly always an enemy (ferromagnetic), particulary since there will be large currents in the output stage.
 

vdi_nenna

Member
Paid Member
2000-10-10 7:27 pm
PA, USA
Fe Parts in Case

What are the effects, Petter? Most mid-hi fed. audio equipment uses sheet metal. I understand that most of it isn't high current apps, but how much difference can 12 bolts and 4 rods have? Wouldn't the surrounding case be more of a concern?

I checked and they are magnetic. Brass parts wouldn't be that much more in price, I guess, if I can find them. I have to check my sources...

thanks!!
 
Cheap boxes

If you look inside even very expensive audio equipment, you will find a lot of cheap parts. One of the most expensive portions of an amp (and let's face it, they are ALL designed to a budget) is the box.

Building boxes out of Al is a pain in the butt. They are expensive, and box manufacturers don't necessarily have equipment for this.

Folding some cheap strong iron is easy, and if you paint it afterwards, nobody can tell the difference anyway.

Anything magnetizable is bad in the box, end of discussion. Ideally, you would put transformers externally as well.