Ian Vincent Posted January 28, 2017 Report Share Posted January 28, 2017 (edited) From what I remember of my school metalwork classes, you don't have to quench copper to anneal it. You can let it air cool if you want. It will still be soft and malleable. Best is to quench in mild sulphuric acid. Cleans it up a treat. Rgds Ian Edited January 28, 2017 by Ian Vincent Quote Link to post Share on other sites
peejay4A Posted January 28, 2017 Report Share Posted January 28, 2017 You can cool either way for copper and brass. Air or sand cooling for steel or else you'll harden it. Quote Link to post Share on other sites
Motorsport Mickey Posted January 28, 2017 Report Share Posted January 28, 2017 "Best is to quench in mild sulphuric acid. Cleans it up a treat." Don't arf make you cough , mask or not.! In our Toolroom engineering classes when completing our apprenticeships we frequently visited other expert establishments to observe and question their methods and reasons why and how they carried out certain functions of metalworking. Amongst them a specialist welding shop and of great interest a local blacksmith (because of a dearth of blacksmiths in the 1970s this was an afternoon out on a bus ...yippee !) to observe and question them regarding metal work hardening and softening techniques. Their practice when annealing any copper items larger than a couple of inches square was to build a covered area in "firebricks" (making a makeshift oven) and then after achieving the required temperature normally gauged by colour change to allow it to air cool in a "protected" area away from chills, quenching was regarded as possibly introducing an element of work hardening to the surface area which is after all why the item is being annealed. Mick Richards Quote Link to post Share on other sites
Andy Moltu Posted January 29, 2017 Report Share Posted January 29, 2017 Why re-use a head gasket unless you are stuck in the middle of a long trip? You've got the head off so unless your budget precludes it get hardened valve seas inserted. Quote Link to post Share on other sites
Motorsport Mickey Posted January 29, 2017 Report Share Posted January 29, 2017 (edited) "Why re-use a head gasket unless you are stuck in the middle of a long trip?" Cos the solid copper head gaskets aren't cheap (never bought one but I'd guess over £80) and part of the justification of costs hinges around them reusable after annealing. On the competition engines I always used the steel shim gaskets. Mick Richards Edited January 29, 2017 by Motorsport Mickey Quote Link to post Share on other sites
boxofbits Posted January 29, 2017 Report Share Posted January 29, 2017 It might pay to at least re/cut first and then grind the valves in as if the seat is badly burned it will take some time to lap only. Kevin Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.