Amplifier Enclosure

[joetama]

I'm in the process of building my own amplifier right now. I have pretty much everything on order part wise except a case. I have done googleing, calling, emailing and yet nothing that looks promising. I found one company that I liked but they are out of business apparently. I'm getting to the point where I might just use two large heatsinks as the sides of the amplifier and get sheet metal and make the rest of the enclosure and have a local machine shop make the front plate.

Anyway, does anyone on here have links or advise about enclosures or building one from scratch?

Also, where is a good place to get heatsinks from? The only place I have found that makes what I'm looking for is Conrad.


Thanks,
Joe

[Gir]

eBay usually has some good heatsinks, but I know some of the guys have a good place for them. I can't remember it right now...

[---k---]

I once saw in AudioXpress someone recommend (and I know this is going to sound strange, but) a cake pan! The specifically recommended the real thick ones by Wilton Industries with the rolled edge. I don't remember what you use for a bottom. I guess a flat plat and use small angle brackets to attach it to the side of the pan..

I have seen one of the pans they recommend (Wilton is about 5 miles from my house and every July they have a blow out sale). They are thick and have a nice black finish. I can see how they would make a nice enclosure. But, I have never used one as such.

Anyway, just an off-the-wall suggestion.

[Hdale85]

Cake pans were for tube amps I believe and yeah I've seen that used a bit.

[Doug Fraser]

Here are the 2 threads where this has been discussed.

https://www.htguide.com/forum/showthread.php?t=30047

https://www.htguide.com/forum/showthread.php?t=25289

They pretty much reference the same vendors

I too did a search and this site has the cases I like the best

http://www.modu.it/homeeng.html

and specifically this one

http://www.modu.it/pesantedeng.html

or this one



Doug

[joetama]

Thanks guys.

Sorry about the two other threads. I must not have search for the right parameters.

[Paul Ebert]

The modu enclosures are very nice, but you pay a lot for shipping, I seem to recall.

Joe, you might check www.diyenclosures.com. I've bought a few from him (he's a fellow diy'er that has tried to make a business of this on the side) and have been pleased with them. Unfortunately, as he went through his initial stock, he didn't want to replentish it until the initial was gone, so it kind of languished. But if you can find something that fits your needs I think you'd be pleased.

One other idea I've toyed around with is using black acrylic for the faceplate. Wouldn't work too well if the amp generated a lot of heat...

[Martyn]

I designed my own using heatsinks for the sides:

[relder]

I'm getting to the point where I might just use two large heatsinks as the sides of the amplifier and get sheet metal and make the rest of the enclosure and have a local machine shop make the front plate.

That's basically what I did, if you have a diyaudio acct. you can see pictures here My Aleph at diyaudio.com

Other random URLs I've bookmarked (haven't dealt with any of them):

http://par-metal.com/

http://www.lansing-enclosures.com/main/index.html

http://www.hexateq-av.com/diy_zone.html

[joetama]

Ok...

Thanks for the links and advise.

I think I am just going to build my own out of heatsinks and sheet metal.

Relder did you just drill the holes in the top yourself?

I was debating doing something like that or just using some perforated sheet metal.

Also, what material (Aluminum, Steel, Stainless) and gauge did guys use?

I've cut and bent sheet metal a little before, but it was pretty thin stuff and I just used snips and a block of wood+hammer. What methods did you guys use for cutting and bending. (I don't think I'm going to bend much if at all for this project)

I have a local machine/weld shop that has built things for me in the past. I wonder if they could just cut the metal to the size I need it.

[cjd]

Couple other places to consider:

Par-metal

And, if you want to do your own, one of the best sources I've found:

Online metals

C

[relder]

Relder did you just drill the holes in the top yourself?

Yep, my drill press was definately my friend on that project.

I was debating doing something like that or just using some perforated sheet metal.

Also, what material (Aluminum, Steel, Stainless) and gauge did guys use?

I've cut and bent sheet metal a little before, but it was pretty thin stuff and I just used snips and a block of wood+hammer. What methods did you guys use for cutting and bending. (I don't think I'm going to bend much if at all for this project)

I have a local machine/weld shop that has built things for me in the past. I wonder if they could just cut the metal to the size I need it.

I ordered aluminum plate from onlinemetals.com to size, or a touch over size (can't remember). I think it was 1/8" for the top and 3/16" for bottom, back. The cuts from onlinemetals.com are done with a shear press thing, so the edge finish ain't great, also, the shear puts some small indentation marks (running the entire length) where it pressed the two pieces apart. I bought a Freud non-ferrous metals blade for my table saw, which does leave a decent finish (only light sanding required after that), to trim up the pieces, make them square and get a decent finish. I then used pieces of L channel aluminum to screw the pieces together.

[chasw98]

Go to Apex Jr. Steve usually has some overstock heatsinks at a good price if you are thinking of building your own case.

http://www.apexjr.com/Sinks.htm

[benchtester]

I designed my own using heatsinks for the sides:

Martyn: That's a real nice looking enclosure. :T

[Hdale85]

I like the ones on ebay I have bought them and they are excellent.

eBay links not available

This guy is awesome will cut the sinks down to any size you want and the prices will be a little less if you email him and deal outside of ebay. Very fast shipping as well!

[Paul Ebert]

For those of you who have bought aluminum plate from onlinemetals.com, how was the finish? Did you have to sand out scratches or the like?

My other question is: anodized, painted, or left bare? I seem to recall that anodizing in small quantities (1) is expensive. Is this still the case?

[relder]

For those of you who have bought aluminum plate from onlinemetals.com, how was the finish? Did you have to sand out scratches or the like?

My other question is: anodized, painted, or left bare? I seem to recall that anodizing in small quantities (1) is expensive. Is this still the case?

You may have to sand out some scratches and printing. I left mine bare after carefully sanding in one direction to create a brushed look. Still looks great, but easily fingerprinted.

[Hdale85]

If you like the brushed aluminum look you can get some medium grit sand paper and sand in one direction several times until you get the finish you want and then go over it with a clear coat.

[joetama]

What aluminum number do you guys use?

I'm guessing 6061 is the most common?

[David_D]

What aluminum number do you guys use?

I'm guessing 6061 is the most common?

Hi Joe,
6061 is the most commonly available aluminum. It is extruded and not cast. Although softer than some, an anodized coating will add a sufficient tougher layer. If you do consider anodizing, I have some tips. All of the platers I have dealt with deal on lot charges. So, one could have an entire enclosure anodized for the cost of the face plate. If you are thinking about an off the shelf enclosure then I would use the same grade of aluminum for the face plate, as different grade require different anodizing recipes and this would increase one’s lot charge. Also, I would anodize all the materials black as this minimizes color variances across aluminum grades and large panels. I have seen large panels of aluminum that have had a clear anodize finish be infinite shades of silver to brown across a single piece.
Sorry for rambling on. I have a lot of custom machined pieces anodized in my business.

[joetama]

No problem with the rambling. It's welcome, sometimes that is where the best ideas come from.


David what grade of aluminum would your recommend? Is there a major benefit to Anodizing vs Painting? Also, what is the usual charge for such anodizing?

[David_D]

No problem with the rambling. It's welcome, sometimes that is where the best ideas come from.


David what grade of aluminum would your recommend? Is there a major benefit to Anodizing vs Painting? Also, what is the usual charge for such anodizing?

Hoffman rack enclosures are made out of 6063-T6 alloy. These are a typical sheet metal bent enclosure. Cast enclosures and extruded enclosures are made out of different alloys.
Due a search for aluminum on McMaster-Carr’s site and they have a very good description of each kind of grade. I would contact the manufacturer of your specific enclosure and choose the same grade. This would keep anodizing costs down, but may be outweighed by the cost of the raw aluminum faceplate.
Anodizing normally runs me about $60-$85 a lot of 4-16 pieces of like materials.
On a side note, laser engraving looks great over black anodize. (It turns the characters a silver color) Most places can engrave off of a pdf file and is very cheap, my machinery tags which are 2” x 6” and has about 6 lines & a graphic. (Company name, logo, & address) run me about $12 each.

[Hdale85]

Umm engravings can very greatly by cost. If you go to a local place and have it done it can be very expensive for just one piece. The way you get it real cheap is by doing bulk orders of engraving and what not. I was looking into doing some panels before and this was the case of course they were making the entire panel and not just engraving it. I guess it just depends on where you go

[joetama]

My GF is an artist and she silk screens for fun (painter by training).

I got a bunch of little metal plates for her to play with. So, pretty much the cost of a screen & the ink and I can get everything put on the amplifier I want.

I asked her if she was sure she could do it. Knowing I had doubts, she showed me pictures of a project that a guy at her school made. Apparently, if I remember the story right her best friend is sort of dating this guy but not. (Art kids are weird sometimes.) Anyway, he took all his aluminum rack panels off his DJ Rack, stripped them and printed these sweet looking swirls and lines on them with about different 20 colors. It was pretty intense. She said he had to use a special ink to get it to stick. I admit I wasn't really listening, I was thinking more along the lines of what the would mean for my project. I'm trying to find the link but I'm not having any luck.

[Hdale85]

I've thought of silk screening my amp racks. It's relatively simple you use photo sensitive transfer stuff and what not. So you just print it out on this paper from your computer and then use a light to transfer it to the other stuff or something. It's been a while but its really not hard.

[benchtester]

Labeling Amp enclosures

The laser engraving is good. It can remove anodizing or paint. I heard that you could remove black anodizing and then have the panel gold anodized to color the labels. I haven't tried this yet, but it sounds cool.

If you make a front panel out of wood or plastic (including Corian); the laser can burn depth. When I did Corian, I coated it with water soluble mold release (PVA) before the engraving. After the engraving, I squeegeed on contrasting paint. After it dried I washed off the mold release and excess paint.

For those that make their own circuit boards with the toner transfer method (iron-on), you can do the same thing for the front panel. I wet sanded the aluminum to get a satin finish. Transfered the toner labels. Then covered it with clear coat lacquer for durability. (While some people like the transparency film sheets, I like the water release decal paper.) It looked pretty good.

[David_D]

As far as laser engraving... This is not a traditional engraving process where it actually removes material from the aluminum. I do not know about softer materials like plastics. But, on anodized aluminum it sort of burns through the anodize leaving the aluminum underneath. You are right Dougie, cost will all depend on where one goes and the scope of the project. Upon doing an extensive amount of research to produce a suitable tag to put on my equipment, laser engraving was by far the most cost effective. Here's an example what laser engraving does to black anodized aluminum.

[rlim]

spray paint on aluminum?

Has anyone tried spray painting on aluminum and got decent results? How would one decide whether to spray paint or to anodize? I am currently making an amplifier enclosure myself and just cut some aluminum pieces yesterday. Not sure which route to take once I drilled all the holes. Seems like spray painting would be easier since I don't have anodizing equipment, but not sure what the outcome would be.

Richard

[Dennis H]

I think, for an amp, spray painting will work just fine. Clean and sand the aluminum before you paint it. If you were painting an airplane, you'd need to get into fancy primers, etc. to get the paint to hold up to the weather and keep the aluminum from corroding but, for an amp indoors, plain old flat black enamel should be good enough.

Edit: for the lettering, if you're on a budget, go to an office supply store and buy 'dry transfer' lettering sheets. They're good enough for ON, OFF, etc. Basically they are black or white letters on the back of a plastic sheet. Rub over the letters with a pencil or a pointed stick and they will transfer to whatever is underneath.

[Hdale85]

Just don't spray paint any heatsinks. The paint is far to thick and would alter the cooling properties of the heatsink. Anodizing is the best way as your whole chassis becomes a nice big heatsink If it's all aluminum. Well this works if its anodized or bare aluminum.

[Dennis H]

We can debate that one Dougie. I would think (but don't know for sure) that a thin coat of black paint on a heatsink would work better than bare aluminum or silver anodizing. Black radiates heat better than silver.

[Glen B]

I've purchased a few chassis from Par-Metal. They may not be the most exotic looking but the company is easy to do business with, prices are reasonable and they will punch holes to your specification if you furnish a drawing.

My DIY balanced power conditioner in a Par-Metal chassis:

[Hdale85]

Black may radiate heat but! Paint adds a rather thick layer of paint between the air and the heatsink. Black anodizing is a very very thin layer and actually bonds to the metal. No matter how thin you try and spray paint its always going to be thicker then anodizing.

[joetama]

I've purchased a few chassis from Par-Metal. They may not be the most exotic looking but the company is easy to do business with, prices are reasonable and they will punch holes to your specification if you furnish a drawing.

My DIY balanced power conditioner in a Par-Metal chassis:

Balanced power conditioner? More information is required.

[Hdale85]

I think there is a thread here somewhere on it. Or maybe its on Thomas's site or something?

[ThomasW]

Balanced power conditioner? More information is required.

https://www.htguide.com/forum/showthread.php?p=373259#post373259

[joetama]

Wow... Thanks...