Bulkhead re-spray tips

[Robin]

I need to tidy up the bulkhead on my Vitesse mk2 - primarily because of brake/clutch fluid drips affecting the paint around the master cylinders. So my plan is to remove the cylinders, wiper motor , and heater and then rub down the area ready to spray a primer and top coat using aerosol cans. Three questions;

1. Is newspaper and masking tape ok to use to cover non-painted areas or should I use something else?

2. How long do I need to leave the paint to dry before rubbing down between coats.

3. How fragile are the brake / clutch pipes i.e. can I simply move them out of the way or will they break?

Any other tips?

Thanks

 

 

[pirate]

I'm doing mine at the moment part of the restoration.

Newspaper and masking tape is fine I have covered the engine with an old sheet just to keep overspray off, I'm using a compressor and spray gun.

If your putting a few coats of primer on, you can spray the next coat as soon as the last one is touch dry without rubbing down, it will bond ok.

I would give the primer overnight to dry before lightly rubbing down before top coat, be careful as you can soon rub through to bare metal again.

If the pipes look to be in good order not pitted with rust you should be able to move them enough to do the repair.

hope it helps.

[Paulfc]

Hi, I've just done mine with aerosol etch primer in readiness for covering with an epoxy primer and then top coat. Out of interest, I used Halfords etch primer which I found excellent. it gave a quality coverage and no runs. I had to finish off with an alternative etch (I had a time constraint and couldn't get to Halfords) which was much thinner and needed a much longer and more careful application. Lesson learnt: don't assume all paints are the same quality/consistency. Well  worth investing 5 minutes assessing the characteristics of the product you've chosen before applying.

Paul 

[NonMember]

The only problem with using newspaper for masking is that the solvents in the paint can disolve the ink and imprint it on the panel you're trying to protect. That only really happens if you get it actually wet, though, so it's very unlikely. However, I find that I receive quite  a lot of small parts shipped in big boxes with half-a-roll of plain brown paper for packing, so I keep that paper for masking purposes to avoid any risk.

Other than that, I agree with @pirate - put a good few coats of primer on at ten minute to half hour intervals, then leave overnight before top coat. The "light rubbing down" really is just to remove any dustiness or greasiness and might not even be necessary.

[dougbgt6]

Yep,

I did mine as three sections, battery compartment, middle section and pedal end. The battery compartment, and pedal end needed extensive cleaning up, sanding, de-rusting and rust killer primer. The middle section was in OK condition so just some light sanding to key in more top coat. I sprayed and completed the sections one at , easier to mask off whole sections than everything individually. Newspaper and masking tape works fine, I undid the pipe retaining clips then lifted the pipes slightly, wrapped them in newspaper and sprayed around them. I didn't do any sanding between coats and resprayed when touch dry.

Doug

[Bfg]

1.  I often use pizza or cereal packaging card for masking,  or the end-of-roll vinyl wallpaper.  It can be folded and better holds its shape without draping. I find blue masking tape better than the cream coloured stuff. It's less sticky but holds everything well enough for the duration of painting.  However, when painting in the engine bay - it's also worth covering the underside of a felt insulated the bonnet !  In short, consider where dust, fluff, flies, rain, coffee mugs &/or children's sticky fingers might come from. ☺️  

2.  remove or mask over any fittings that weren't painted, painted over screws, nut and bolt heads, and plastic parts.  Likewise mask up wiring and rubber hoses, seals etc. When painted over they make the whole job look tacky and cheap.   NB. a decent pair of kitchen scissors to cut the masking tape makes detailed masking so much easier than trying to tear the tape.   And wash your hands frequently throughout the whole preparation and painting process ..because fingerprints are naturally oily and acidic.  Personally I can't get on with wearing gloves ..as I rely on tactile feel as much as the visual  Also, applying masking tape when wearing gloves is to me like giving Data a Chinese finger puzzle !  (Trekkies will know what I'm talking about). 

3.  once the area is scraped and roughly cleaned, wire brushed, treated with rust eating chemicals, and the so forth -  I use aerosol carb cleaner and clean tissue to remove oil, grime, and other fluid, acidic, and polish contaminates.   <  EDIT : I guess this ought to have been #1 because scraping and cleaning is done before masking.  Sorry, I was answering your question and only then carried on to explain ' the process ' I follow >

4.  Whenever sanding / rubbing down focus first on the inside of corners and awkward / difficult faces.  Don't rub down the high spots first ..because when you're working the difficult places you'll probably be scratching those places again. So inside and difficult first and then ..only with the finer grit of wet 'n dry go over the whole. 

5.  once sanded through the grades to say 400 grit,  I like to use cold-galvanizing aerosol spray. This is zinc and so helps prevent further corrosion. I use this to fill in any light rust pitting and the edges of chipped original paint.   NB.  Any Painting is best done where there's no breeze and where the air temperature is above 15 deg.c.  If you're forced to paint outside then  cardboard boxes can be opened up and used as screens.   Damming around car's underside will help prevent a breeze from coming upwards. 

Drying time depends on air temperature & humidity, and also the temperature of the area / metal being painted.  ie. it can take ten times as long for paint to dry on a cold foggy day (because the drying evaporation of paint is so slow).  Even if you are using two-pack paints which cure by chemical reaction they are sensitive to cold. 

This is worth remembering especially when painting vertical surfaces ..where the paint might tend to run.  Pre-warming the area / the metal up will accelerate the drying process and prevent runs.

6.     Because cold galvanising is light grey in colour, it's easy to see where a light smear of filler will smooth out any fill deeper paint edges and pitting.  Fine-paste filler is useful for these shallow areas.  Once that's dried (also subject to temperature) it will also need rubbing down.  Inside corners first again, and using a wood or rubber block whenever you can ..even if that's only the size of a pencil eraser, will help you keep the edges straight and surfaces fair. 

7. then respray those areas with another coat of zinc, or if you prefer a base colour primer. 

8. Any paint you've recently applied will not be that hard, and primers and zinc rub dow easily anyways so only use fine wet 'n dry 400 then 600 grit.

NB. most primers are not moisture proof, so they do need a top coat. 

8.  many paint suppliers also sell tack-cloths. These are used to wipe the rubbed down surface off, to get ride of any fine dust particles.

9. spray your top coat colour,  spraying into the corners and difficult places first..  Not too much paint.  It is better to apply very light coats in quick succession (so they chemically adhere to each other). The object then is to apply just enough paint to get a wet look. Then stop.  Allow that to dry for a short while, and repeat. Do this as many times as is needed to get an even colour.

10.  Let this dry for 24 hours, and then if there's bloom (dullness) from over-spray then that might be very carefully rubbed smooth (corners first, block, etc) using 800 or 1000 grit wet n' dry with water and a drip of washing up liquid (to lubricate the action).

11. tissue dry and assess whether another top coat is needed.  If so, then use a clean tack cloth first.  Alternatively you might consider a clear lacquer if the paint's colour is good. I've used petrol resistant clear lacquer to good effect. I also find clear lacquer to be a better moisture barrier than most paints (rust proofing). 

11B. If you decide you're not going to apply any more paint, then any dullness from the very fine rubbing down can be polished out with colour restorer.  Again remember that freshly applied paint is still soft, so don't be too aggressive with it. 

12. Leave for as long as you can, for the layers of paint to harden, before refitting bulkhead ancillaries  ..minimum of 48 hours if you can. Otherwise you'll see washers imprinting themselves into the paint.  Gentle heat can be applied simply by closing the bonnet (after the paint is surface dry) and placing a fan heater on a low-setting under the engine bay. 

NB. When the area to be repainted is under / need brake fluids or the battery you might consider using an epoxy paint, or a petrol tank sealant like POR-15.  These are a thousand times more resilient to future chemical / acid damage than most car paints.     

Hope that helps,

Bfg.

[Robin]

That's brilliant - thanks to everyone for their tips and once again the Forum is just a fantastic resource of info.

 

Will post a pic when I've done it!