Who can anneal copper head gaskets in the N/E ? Long story short, a particular company who will remain nameless, has messed up my copper head gasket once again for my Belly Tanker, powered by a GMC Jimmy 302. The gaskets are being sent back to me without being annealed, after the first two gaskets had different bore sizes !!!!! I beleive 800F to 900F is required to properly anneal a copper head gasket ? I don't feel real comfortable using a torch to anneal the gaskets, due to the amount of money I paid, for one off gaskets. Thx....
Any industrial processing facility can do it, there would be a batch charge, my guess is like $75. You would have to furnish the heat specs as well as any fixturing that would be required, outside of a big plate or something over it to maintain flatness. Bob
What are the temp's you wish to reach and for how long if I do use a furnace/oven , 800 F ? If annealing using a torch, what color are you looking for ? Any tricks ? Thx, Neil...
Neil, I used to anneal the copper head gasket for my Enfield. You can use either an oxy/acyetelene torch or a propane torch. I would hold the gasket with a pair of pliers and heat the gasket until it was bright red. It doesn't have to be uniform, because after the copper has been heated and allowed to cool naturally, (DON"T quench it!) you're all done. Simple as that. Hope that helps. Greg.
I soot the gasket on one side with straight acyetelene and then using a normal soft flame heat the opposit side and burn the soot off. When I do my Dodge Bros gasket I think I'll use the propane torch to burn off the soot
Find someone that works in the airline 'bidness, that might have access to a heat treating oven for aluminum........We have one here at work, that stays on 24-7, and the temps we use for solution heat treating, the range is 820-920 degrees. If thats' the temps you are looking for.....................10 minutes and you should be good.
Excellent, thanks for your help.... I was concerned with using the torch as this will be my first time annealing an expensive, copper head gasket... Thanks to all... Neil....
I used to anneal copper head gaskets for English motorcycles by laying the gasket on a piece of steel plate, heating it with a welding torch and sliding it off the plate into a bucket of water. Don't remember where I learned this but it was probably some English repair manual. Copper is the opposite of steel, you heat it and quench it to anneal. You shouldn't need to anneal a gasket that has never been used, it should be soft to start with. What does the manufacturer say? 800 - 900 degrees seems pretty high. ................Later............................. Here is an interesting tutorial on the use of copper head gaskets, from a gasket manufacturer. It seems I was doing it wrong all those years ago. http://www.headgasket.com/preinstall.html
from the above post... NOTE: It is unclear if annealing is needed in all applications. There are no controlled tests to date that definitively proove the benefit of annealing. It is felt that annealing will allow copper to "deform" slightly to fill in the surface marks left by machining and to deform where a steel wire "O" ring has been placed around the cylinder bore. Annealing makes the copper soft. This may defeat your purpose if you are trying to optimize on head gasket streignth. If our GWG P/5 gasket dressing is used we believe that annealing is not needed in most cases. After the gasket has been worked to proper size it is ready for use. It may be necessary to re-anneal the gasket if it has work hardened. Annealing is a heat treatment that softens copper. The gasket may work harden somewhat if you have worked with it but it still should be soft enough for use. Since there is oxygen within the copper it can only be annealed (using flame heat) a few times before it becomes somewhat brittle. I don't rec. reannealing more than three times. OXY/ACETYLENE TORCHES may give TOO MUCH HEAT. We do NOT REC. this method. Heat the metal until it appears just dark red while in a dark location. More red or orange is not necessary. Ideally, a temperature of about 900d F is optimal. Let air cool. Once cool (in about five - ten minutes) brush with the"Scotch-Bright" pad on a flat hard surface to clean and flatten. A flaky post annealing residue is normal after annealing in air. Bright annealing in an inert gas oven is optimal and prevents this oxidation.
If you want to use the torch then use a large tip, propane will do you don't need o/a. Lay the gasket out flat on a firebrick (you can buy large bricks cheaply from kiln supplies places) or series of firebricks, or put some small BBQ type rocks in a tray, and heat all over as uniformly as you can. Cheater tip: You don't need to do anything to the copper, when you light your torch just turn out the lights. You will be able to see the colour of the copper change easily. When it is a dull cherry red (not bright orange red) it is ready. It can be hard to see in bright lights as the copper develops a black oxide coating as you heat it up. Air cooling would be better but it won't cause a problem if you quench it, just make sure you get the whole thing in as quickly as possible. Don't feed it in slowly. To clean it up after the best thing to use is sulfuric acid solution. Either 10:1 water to acid or if you are not in a hurry 20:1 (you can put your hand in this strength solution without damage ...unless you have a cut or scratch). Leave it in until it is all powdery looking copper colour again then give it a once over with a soft brass brush. Sulfuric acid can be bought in small quantities from jewellery supplies stores.
I was under the impression that copper very quickly age-hardened after annealing, so it almost had to be used straight away or it would be back to where it was before annealing. This was from a job I was involved in many years ago that involved deeply swaging holes in copper sheet for something. It basically meant you had to do the annealing yourself as if you sent it away, by the time it got back to you the next day you had wasted your time and money. Can anyone confirm if that is true?
Neil, I use Flatout Group Gaskets. Mark is a great guy to deal with, and their service is great! https://www.flatoutgroup.com/gaskets.aspx Instead of annealed, they have a rubber coated copper gasket, for better sealing. Price is good, service is great! We had one set of gaskets that were wrong-they sent the new, correct ones, that same week!
I don't think they have a CAD design for the Jimmy as of yet, as I contacted them late last fall. I already went through the CAD design process ($$$) with the other company who will remain nameless, I will only advise the name of a company if I am PM'ed...... I assume this is where you purchased your Caddy gaskets and not the GMC gasket ? Thx, Neil.....
Neil, that's correct, as I have not yet purchased a Jimmy gasket. A question here- did you receive a copy of the CAD file? If so, all you need to do is send it to Mark Adelizzi, [email protected]. If you haven't received a copy, I'd request it-after all, you paid for it! I know you've already spent the money, and that's rough. What I like about Mark is, once he has my design, I can order gaskets on Monday, and receive them by Friday! I know this, because after coating the heads and pistons, we didn't like the quench depth. I ordered thicker gaskets a week ago, and we already have them. That's hugely important to me!
You would really have to know the alloy to make the best decision. My experience in annealing copper involves the added process following machining and bending operations to remove stresses. Most alloys or copper will age harden regardless, but copper will always retain it's inherent soft qualities. If the gaskets are relatively straight and not nicked up in any way, I would just toss them on. Bob
I felt the 'o' ring and reciever grrove to be more important than annealing the copper. This 'soft' copper is a relative term and if any of you guys had to take a file 'back in the day' to BBC head gaskets to fit it to the combustion chamber then you know what i mean. We'd get a little too lean on the tuneup and it'd push the gasket so i have had a bit of experience of what hot-then-cooled copper is like and i can tell you this - it take a scientific tool to convience me that copper gets softer. The concept that this 'annealed' copper is soft enough to make a good seal is a lot of hooey. What you really need is proper head and deck surface finish - absolutely flat, no ridges etc, mirror-like surface with 'o' ring in deck or head with a receiver groove for the 'o' ring. The 'o' rings should be over .100 apart where the cylinders join each other, if closer then the 'o' rings should become a figure '8' so that the wire is a single strand between the cylinders. Closer than .100 and the copper 'piles' up because it has nowhere to stretch to and you'll have problems. Annealing is some sort of bandaid/compensate method for improper surface prep - if you do your machine work right you don't worry about how soft the copper is. If need be i can pull the head off and show you the surface finish on my engine with 17:1 compression and 2 stages of nitrous that i never worry about blowing a head gasket - that is the least of my worries.
Does anyone have experience using the "Flat Ring" which is approximately .005" thick in place of using an O-Ring ?
Neil, I haven't heard of the flat ring. Can you provide more info? Hopefully, someone will weigh in and answer your question!
One line in there puzzled me: "Our practice is to place the ring on the top of the gasket facing the head." I thought the 0-rings seated in grooves in the block, mainly because the bore offers a reference for the groove, whereas the combustion chamber in the head could be any shape?
I think they are talking about the 'flat ring' Neil asked about. It sounds as if there is no receiver goove on the heads?
Great thread. I'm a big fan of copper for its metalurgic properties. Annealing is about heating metal to relax it at the molecular level. I've heard two EQUALLY promising ideas here. First, annealing a copper gasket in place, or just pre-installation. SEEMS the copper plate would be very cooperative to compression, YET very strong across the area sealed! Now (2), when annealing metals, often the NEXT logical step is QUENCHING the item in water, thus realigning the metal molecules and, presumably, making the piece all the stronger. For THAT, one would need an oven rather than a torch. Which is better? I just do not have any info about copper in this situation. But, great, thought-provoking thread. Great proposition!
If i was making my gaskets from dead soft copper I would not need to anneal them. But I am starting with half hard copper which cuts much nicer and am doing what i was told years ago.
Hiya, Rich! Hey, bro. Please define those two terms for the unintiated among us. I assume both "dead soft" and "hard" copper are rolled stock, am I correct?
I checked again on melting temps. Copper is around 2,000. So, from what I read, if you do it with a torch, you make the copper GLOW red (not all the way to white-hot). That should relax the molecules and make them malleable to further uses. Similarly, if using an oven or kiln 900 or a thousand degrees should do it.
Having no experience with this, and not sure why it needs to be done, could you heat it on a bed of red hot coals?
This is a cool thread. I now know 100% more about copper head gaskets than I did five minutes ago. Carry on please!
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