Classic cars forum & vehicle restoration.

[Ray White]

Here I have the complete new set of special screws and nuts required for assembling the side screens to their respective frames.

Unfortunately, the 3/16" BSF threads on the nuts and bolts are a disappointingly loose fit.


If I use these fixings, what would be the best way to unsure they stay done up.?

I have some thread locker...would that work with stainless steel (nuts) against chrome? or does it need heat to cure?

[Vintage Fly Guy]

You could perhaps try two or three turns of plumber's PTFE tape on the threads where the nut will be when tightened (so its hidden) to take up the slack, but give you a chance of undoing them again if you need to?

Check them regularly and if they start coming undone then you could always try putting a small dot of a rubbery, waterproof, type glue (such as 'Evo-stick Serious Glue') on the threads where the nut will sit. This might allow you to undo them again if you need to, rather than using something that sets rock hard.

Be careful not to get that glue on anything else when applying it, as it sticks to everything and doesn't like coming off (particularly on cloth type materials), so apply sparingly and accurately and keep it off your fingers! See if that works and check them to make sure they aren't coming undone after each journey until you're confident they're staying put.

I'm not a huge fan of threadlock as it can be a terrible job to undo something if too much has been applied. So where there's no heat involved and it's not safety critical, I'd experiment a bit and try to use something else. The opinions of others may vary though!

NB Before doing this, do check that the loose fit hasn't been done intentionally for some reason or other. It doesn't look like the domed heads of the bolts are slotted either, so do give some thought as to how you'd remove them again if you ever needed to, before 'welding' them together with some sort of adhesive.

[Ray White]

Thanks for your ideas. I tried PTFE tape but the threads seem too slippery for it although perhaps if I persevered with it I might get somewhere. Incidentally, you can get liquid PTFE so that might work better ...?

I know what my luck is like...if I try using glue it will somehow find it's way onto the screens!

[ukdave2002]

A cheap way of fixing worn shafts is to knurl them, a bit of a bodge but sometimes needs must! you could try something similar by holding the screws by the thread in mole grips, then turning them to slightly rough up the threads.

Not perfect by any stretch of the imagination, but may work?

Or use a medium thread lock like Loctite 242.

[Ray White]