320 pounds of heat sinks....

I've read past posts but still stuck whether or not I should spend the time trying to determine what's what and then trying to separate the metals. I was originally just going to take them direct to my buyer as is but I'm thinking I could do better than the $0.50/lb he's offering. I guess I'm still confused on cast aluminum versus normAl aluminum. Could I make better money going to a regular scrap yard if I knew how to separate the metals? I wouldn't ask this question cause I know it's been brought up several times but I'm sitting on some good poundage and I'm still confused. Help a newby out. Thanks.

What sort of heatsinks? Post a pic.

Being that I have over 300 pounds they vary. All of them from computers or servers though. I'll get photos up soon.

They should be Alum extrusions. Some are flat that, i put in the sheet alum, the find or bladed ones are Ext.

I'm hoping someone will share info on the heavier based ones that I've read are copper. Extrusion...... Is that cast? Does cast pay the same?

Almost top to bottom with alum prices. Ext. pays better around .55 a lb here. and cast was at .38 last time and may be lower now. Ive never foumd a cast heat sink tho. If you think its cast alum, hit it with a hammer and it will break, not bend.

The heat sinks with the copper/alum you need to separate for the best money. I just took a load in from computers and tv boards.
I had some classified as old sheet alum. for .55lb
some were alum. MCL (?)which paid .62lb
and the rest were Ext. at .70lb.
I didn't have any cop/alum mix in mine, if they have the copper bottom I think you can shear the fins off in a vise. Then the sinks with copper slugs put it in a vise and right along the slug drive a flat blade screwdriver in and pry the slug out.

I had a bunch with the copper "plug". I pried the fins back and cut through the aluminum extrusion and steel fan bracket until I hit the copper. Then I pried the extrusion off the copper. The yard gave me "copper foundry" (their highest rating) for the plugs. That part was great, the not so great was they gave me aluminum sheet for the fins instead of extrusion.

Bill

Glad i asked. I had no clue what extrusion was, based off the prices Mechanic shared, it was the highest paying. I guess i just need to identify the copper and remove that. Is extrusion heavy? i have a bunch what came out of servers and they are definitely bottom heavy, i was hoping someone would tell me they are copper. I need to take a grinder to them i guess.

All heat sinks with fins is extruded alluminum. If they have copper on them then take the copper off. Sheet alluminum is always bent or pressed to form the shape, extruded is drawn through a die to form the piece. If you look at the end of the heat sink you can tell thieres no way that alluminum could have been bent to make the fins. Cast alluminum is always pored into a mold and most of the time you will be able to see mold marks and the inside corrners will be rounded. I hope this helps, I don't know any other way to put it without being there to show you.

Scrapcrazy. just scratch the bottom with a nail or scerw or cut the side with wire cutters or a file and see what color it is on the inside.

Quote:

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All heat sinks with fins is extruded alluminum.

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I have to disagree there. On this last load I had a big heatsink with a big flat plate and fins, but when you looked at it close the fins were thin sheet bent and pinned to the plate with alum pins. That one went as old sheet. The yard resorted my load while they were weighing it and the majority went as the MCL, and I'm still not 100% sure what they classify MCL as.

Mech688, Ive come across those too. they were in old sterio receivers. also Ive found a couple that were solid ext. and they were nice and heavy. have to guess around 2 lbs a piece

Here are some photo's of Cu/Al heat sinks I had. I seperated the larger sections of Cu by heating them on a propane "turkey" cooker in a SS basket. All I needed to do was heat them hot enough to melt the solder that holds them together. The ones with the Cu tubing I cut the tubing and sold them as Cu/Al radiators.

http://i597.photobucket.com/albums/t...s/P3100093.jpg

Here's a different type.

http://i597.photobucket.com/albums/t...s/P3100092.jpg

Here's one that looks like the bottom is Al but the grinder revealed it was Cu.

http://i597.photobucket.com/albums/t...s/P3100095.jpg

Best of luck, Mike.

Thanks everyone! I have so many of them and its obvious that some are copper and I think it would be worth my time to take the questionable ones to the grinder. It sure would be nice to find some hidden copper in some of this heavy ones. This may be this weekends project. I'll keep you posted.

Alum by me is
Dirty/furnace
Transmissions
Cast
Paint
MLC
Extruded
Alum Cans
Al rims
Cu/Alum Raidators

I would also have to disagree with you happyscraper. I have seen literally hundreds of different heat sinks. Some I will buy as extrusion, some as old sheet and some as MLC.

BTW Mechanic, MLC stands for "mixed low copper clips". This basically means that it is aluminum that has a small % of copper in it. My yard uses it as a catch-all, kind of like old-sheet. The difference between old sheet and MLC is the thickness of the aluminum.

On another note...has anyone done a price analysis on whether it makes fiscal sense to seperate the copper from AL/CU heat sinks? I know some yards will pay you Cu/Al radiator prices for them. I personally don't think the copper recovery is there to justify that price, but if you come to my yard I will pay you close to $1 a lb. with the fan still on them!

Lots of alum info here by grade type... GENERAL ALUMINUM INFORMATION from Aircraft Spruce

my yards here refuse to recognize qny heat sinks as extruded, even after I show them the extrusion marks on the sides and show them it couldnt possably havr been molded, most yrds still have no clue when it comes to comp scrap.

I stand corrected, I have come across like in the pics by miked, like the one in the background, upper left.

Well I brought every single one of my heat sinks to my local yard today. I was trying to hold out but I needed to clear out space, getting rid of them freed up three 20 gal tubs. Based off of the yard I went to today I came away with the understanding there are 3 types of heat sinks. But who knows, they seemed rather confused themselves. Before I brought them to the yard I separated and sorted as I thought was correct. I removed the copper in the ones that didn't take too much time plus I discovered some heat sinks from certain servers were completely copper including the fins, That was an awesome discovery, each one weighed 2.8 pounds and I had 34 of them. I also learned you will find sinks that are bottom heavy and usually shinier on the base than the fins, those were copper 9 out of 10 times. The yard separated and paid in 4 grades.
1.All copper #2 copper $2.80/lb
2. all aluminum. $0.50/lb
3. copper base with aluminum fins $0.80/lb
4. Aluminum with misc. Copper .$0.75/lb

I misplaced my ticket so i don't know the exact grades they classified them,
Not even sure if they did it right but I'm satisfied cause if I would have sold them to my E scrap buyer they
Would have sold for $0.50/lb and today's take averaged $0.87/ lb.
I'm happy believing I made all the right choices with this transaction. I've only been doing this for 4 months
Now and am still learning. If there's one thing I would do different, I would figure out a way to separate more of the copper
From the aluminum.

I honestly think that everytime ive brought in alum I got paid differently. First yard I used would lump it all together regardless if it was sheet, cast, ext, etc. Then they would pay separate for cast. I started using a new yard, and the kid running the scale got confused when he saw all the alum options on the ticket screen, so it got graded as old sheet. Whatever.

I made sure to sort mine before I got to the yard. I also grinded the parts that looked like aluminum but were obviously Copper after being grinded. I wouldn't accept being paid for just aluminum if I knew it was copper. I'm sure the next time I go, even if it's the same guy, he'll be confused all over again.

I've been to three different yards locally, and they all do the same thing. When I give them a copper and aluminum heat sink, they pay me a dirty aluminum price. It's usually like $0.18-$0.25 or something horrific like that. So, now I just keep one in my truck, and anytime I go to a different yard, I ask what they will pay for it. Hopefully I find one soon that will give me a fair price. For now, I am just stockpiling them.

Some of you talk about old sheet aluminum, is ther a diffrance in price? The yards I go to all sheet aluminum pays one price, right now it is .50 it dosn't metter if it's thin, thick,painted or what ever.Although it must be clean of all other metals to get that price.