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[PeteF]

The copper will have been crushed ever so slightly but the annealing will bring it back to size. The crushing will be so tiny anyway you don't need to worry about it.

[Alan R]

Hi REG--------Generally speaking plain Copper gaskets don't have a Fire-Ring as the material is man-enough against the combustion process...A composite gasket will have a Fire Ring ( Made out of a piece of solid metal ) to protect the edge of the weak, thin copper outer sheets and the similarly thin inner material from being burnt---Hence the name "Fire Ring"....PETE F, well-- that's a new one on me I must say but, at a microscopic level you could well be correct however the main point of Annealing is to bring the Copper material back into a soft, ductile state such that it can accommodate any slight imperfections on the Cyl. Head and Barrel mating faces and effect a good, gas-tight seal...Torque-----ride-----re-torque and then re-set your push rods as well...

[PeteF]

Alan, as I understand it, the pressure on the copper alters the molecular structure of the material by forcing the molecules closer together. This does reduce the thickness the tiniest bit (don't know how much - 0.0005 perhaps? even less?) and makes the copper less malleable. Heating to cherry red and keeping it there for a few minutes opens up the molecular structure again.
Don't think that a copper gasket will compensate for any damage to the mating surfaces. Certainly anything you can detect with a fingernail will not be sealed by the copper (though a sealant might help)
People expect too much of gaskets sometimes and are doomed to failure.

[Reg]

Thank you chaps, Copper gasket it will be.

[Alan R]

Hi PETE ....Bloomin 'ek mate--- keep it "real"..LoL !!.. this is Enfield Technology we are discussing.... (Now there's a contradiction in terms if ever ??)..........Seriously though, yes you are quite right and we mustn't forget work hardening from vibration as well....BUT Arfur Fowl ( 0,0005" ) shouldn't make any difference at all at our level...... I agree with REVBAND --- Plain copper gasket, re-anneal, re-use = simples !!

[Presto]

News to me Alan that the material for the composite gaskets supplied by our hosts for Enfields are constructed from metal - copper or any other metal. I thought they were a (man-made?) fibrous material - not a multi-layer metal construction - hence the need for a 'fire ring'.

[PeteF]

Sorry 😀

[Alan R]

Hi PRESTO------ The very word "Composite" itself means}---- Made up of more than one item or element....so a Composite gasket is made up of two or more pieces......There are many permutations that can be had ..... have a look at this ( Item B is what I had in mind )----------> http://scegaskets.com/wp_super_faq/what ... materials/

[Reg]

Positively the last daft question----I hope! Had a go at annealing the old gasket but it started to de-laminate itself. This and got caught red-handed with gasket ,mole grips etc. at the cooker "making the house smell like a garage" so decided to invest in a new one from our hosts which arrived today. And my question is: does it make any difference which way up it goes? There is a definite, almost engraved line following the bore and pushrod tunnels on one side. Sorry to appear a bit dim, but really don't want to have to take the head off again.

[Alan R]

Hi REG------If it started to De-Laminate then it was a Composite Gasket..... Alas it would seem that somewhere along the trail the message has been mis-understood I fear ......Have a re-read of my first reply to you and in particular the link referring to gasket materials.... You DON'T anneal composite gaskets weather they have an outer layer of thin Copper or not... You CAN anneal a plain Copper gasket if done in the appropiate manner....
I don't believe it makes any difference which way round you fit your new gasket UNLESS it says so in the fitting instructions OR the gasket has the word "TOP" or "UPPER FACE" or something similar stamped in it......
............Hard luck on getting caught ( been there--got the plasters and medals --- still with her !!)....