I am on the final stages of stripping down a Focus 08 and all straightforward so far until I got to the gland packings on the two control knob shafts. I have stripped down the valves as far as I can and the gland with the retaining bush just surrendered it’s packing with no fuss. But the one with the internal thread is taking some doing. I am working wet and masked up as the original spec was for asbestos packing so I’m assuming that’s what’s in their still. I have got half way down with scraping between the threads but as my angle of entry decreases the harder it’s becoming. It doesn’t look it in the photo but the top 10mm or so is clear and I’m only just over halfway. I am worried about damaging the threads. I have tried a vinegar bath for an hour and tried again and my next step is just to leave it in overnight but I am hoping someone might have some advice!
A tap might help with cleaning but the remaining packing is now very close to what I’m assuming will be a shoulder before it reduces in diameter. The taper of the tap might mean it doesn’t quite get far enough down. I might just about get my thread gauge in there to check thread. Will have a play tomorrow and see what the vinegar has done overnight. Thanks.
Yes, very true.. but not all taps have a taper.. plug taps are threaded all the way down. Have you got any of the small 'o' ring picks or dental picks?.. Very useful and widely available on fleabay? Good luck with it.
Not sure I’ve got a plug taper and likely not the right size and gauge, though I’ve not been in that section of the toolbox for a while. An O-ring pick got me this far. I’m sure if I keep at it, I will get there eventually.
Not sure if this is available in the UK but I've used it on well stuck asbestos gasket and it makes it a breeze to remove. 18 oz Chisel Gasket Remover | Fastenal
I couldn’t find that exactly but have found similar sounding products. Got a few things to try now, thanks!
Wouldn't it be easier to check the external threads on the part that screws in ? I've found that getting the old graphited string packing out requires a lot of patience. It seems as though you work for ten minutes or more for each short length of a single fibre of the stuff.
Well of course that would be much easier Henry, but if I make life too easy for myself I’ll have nothing left to work on!
Absolutely. Anyone can do things the easy way but the greater the challenge, the greater the sense of achiement.
Getting there with the rebuild, slowly. Made the new seals today, punched a new viton pip for the nrv, a lead gasket for the cap and using graphite foil for the glands. I am hoping for some advice on these threads though. They didn’t appear to have any kind of thread seal on them when I took them off to remove the gland packings but wondered whether I should use something on reassembly? I would usually just coat with copasil but could gas tape them or get a loctite thread sealant. Thanks
No need for anything on the threads, the gland packing does the job. As you tighten the nut, the graphite foil will compress and make the seal just as the small rubber washer on the spindle of a Tilley or Bialaddin control cock does.
Thanks Henry, I understand the gland nut will compress the foil which will seal around the valve shafts, but the graphite would stop against the internal shoulder and these threads are at the other end of the fitting. Sorry, photo not the best. Do I still not need any sealant? Is that due to the fine threads or how the fitting seats against the centre column? Or am I misunderstanding?
Oops, the photo' didn't show. Perhaps it's me that's misunderstanding, although I'm familiar with most systems, I don't have a Focus and appreciate that there may be something in the design that's specific to that particular brand which I'm not familiar with. To be honest, I'm beginning to feel a little out of my depth and would hate to give wrong advice, especially as your lantern uses gasoline. So unless another Focus owner comes in with advice to the contrary, by all means use a smear of copper grease or gas tape on the threads, it won't do any harm but will definitely give you peace of mind.
No, I’m fairly certain it will be me over complicating things Henry! Reckon you’re right, a turn or two of gas tape won’t hurt.
