Mesa Nomad 55 with one of the 12AX7 snow capped and a neat ring around the top of the glass envelope. Obviously due to the bed-spring gauge of spring inside the can. 2Kg to halve the spring length, probably 2/3 compression in use. No point in replacing without changing all the springs or something. How to reform a weak straight compression spring (easily available) to conical or otherwise fit inside the can and the glass touching end be centrally posistioned. ? Secondly there is no dedent to stop the cans rotating other than use of heavy springs - catch 22. What to do, retrofit, without taking the amp apart to get to the inside of the chassis. So far I've discovered a working , but not elegant solution. One of those brass-eyelet hand pincer/dies pushing the die pin outwards to deform a pip in the aluminium, outwards, 1/4 way round so it locates in one of the 2 chassis cutaways. Needs some rubber padding on the outside so the other anvil half does not excessively damage that local area. Any other solutions anyone else has found, particularly forming or re-forming spring metal to something like conical My attempts are very wonky.
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