replacing oil screen gauze

[Derek Sheldon]

After spending virtually the whole of my career soldering anything from wire as thick as your hair to 3 tonne mould cylinders in the security bank note industry I am taking a risk and putting myself up as something of an expert.
There are two main criteria required to make a good joint, cleanliness and a good heat source.
Both surfaces must be impeccably clean, degreased and back to bare metal.
The best method to supply heat for this particular repair is a good sized copper soldering iron heated by gas, say 3” x 1” x1”.
As suggested in a previous post Bakers No3 Soldering spirit is what I would also suggest.

H&S, toxic fumes will come from molten solder and from the soldering spirit, use in a well ventilated area and wear safety goggles and face mask. Also gloves as the spirit contains quite a nasty acid.

1. Having cleaned the appropriate surfaces apply some clean soldering spirit to the areas to be joined, I use a hard wood stick.
2. Tin (solder) the areas to be joined making sure that they are well covered on both the frame and the new cloth.
3. Lay the new wire cloth over the frame. Due to the 3D nature of the frame I always start by attaching the centre web joint. Hold the wire cloth down by using your hard wood stick and apply the heat, watch for the solder to flow. Remove the iron whilst holding the cloth down. Gradually solder your other joints working from the centre.

Tip. Solder the cloth in the areas to be drilled for the mounting bolts to around 1/2” this will allow easy drilling and not fraying.
Hope this helps. Good luck

[Colin Swinbourne]

Derek, this is very useful, and fortunately confirms what I covered during my apprenticeship 30+ years ago and what I’m trying to re-learn now whilst trying to make a new fuel tank! ...and at some point soon I’m also going to have to make some new sump gauze panels.
One question- what/ how do you clean the solder and flux residue to neutralise the flux and stop corrosion?

[Derek Sheldon]

Colin,
Glad you asked, missed that bit out. Imperative that the whole thing is washed down afterwards and if it’s going to sit for a while , oil it up
Good old soap and water, washing up liquid and a stiff wire brushing

[Chris KC]

Fantastic, thanks Derek, I will make a note of that for next time!

Probably still worth saying though that the mesh is useless if oil can flow around it...and a bare minimum of protection even if it can't!

[Stuart Giles]

One question- what/ how do you clean the solder and flux residue to neutralise the flux and stop corrosion?

If you have a dishwasher and it's a SWMBO free zone at the time, putting it in the dishwasher is very effective; dry it as soon as the dishwasher is finished to stop rust forming on the frame.

I find that a nice big copper iron heated with a propane torch or such  is the best thing for a job like this. This flux works really well on steel as well as stainless https://www.solderconnection.com/P584/A8...-Flux.html This flux is really aggressive so needs washing off straightaway after soldering.

[Dave Mann]

Whilst Bakers fluid is a good flux it is highly corrosive and all traces must be removed.

[Jeff Taylor]

Jon,

This is the sort of traditional 'copper iron' that I'd imagine Stuart is referring to - there's various sizes available. I've got one that belonged to my late father who was very good at soldering. On eBay look under 'Blacksmith Collectables' - there seems to be a few on there for not much money.

   

[Derek Sheldon]

Spot on, can’t think how many hours I have spent wielding one of those things

[JonE]

Thanks for all the latest!
(Guess what I found in a box and recently sold on ebay very cheaply after it sitting on there for 6 months...:-)

I'm still wondering whether, if the gauze holes are properly punched, it's necessary to solder the damn thing at all. Surely it will be clamped securely between frame and crankcase and easily removed....

[Chris KC]

Personally I want all the little strands at the edge embedded in solder where they can't fall off in my oil.