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Spray painting, air compressor and stuff questions
I have read a bit of MrToweds 70 page thread looking for the painting bit but got lazy and decided to start a new thread. Please feel free to use this for any painting advice / questions you have but I will start.
What do I need?
I have one of these with one of those on the end.
These
Those
Do I just pour the paint in the paint gun reservoir, fire up the compressor and spray away?
I am planning on practising on the garage door as it is flat, metal and needs painting.
1) What kind of paint do I need for aluminium?
2) What kind of paint do I need for fibreglass?
3) What pre-coating do I need for fibreglass?
Please put a number against your answers so I can link them to the question. If other people add questions (please do!) put numbers against them too so we can link all the questions and answers even if the answers arrive a while after the original question (hope this makes sense)
couple of things:
1. always filter your paint before you put it in the gun, proper paint strainers (a bit like coffee filters) are cheap.
2. For ali you will need to apply an etch primer first, normal primer will look like it adhering ok but will eventually lift.
3. For fibreglass I always use a light coat of etch followed by a standard high build primer.
4. Cant stress enough how important wiping down fibreglass with pre paint is, the wax used to help release fibreglass from the moulds can cause havoc with paint, I usually try and wipe down the whole surface 2 or 3 times.
5. For top coat your limited really without proper breathing gear as 2k is nasty stuff, I have used it in the workshop without and felt ill for hours after. So really cellulose is the best bet for home spraying. Contrary to popular belief it is still readily available from most good paint factors. Jawal still stock it for sale by mail order. The other advantage with cellulose is that given its put on thick enough and given enough time to harden even a ropy finish can usually be rescued with lots of wet sanding with fine paper and polishing.
6. don't be afraid to ask your local paint shop for advice, they are usually glad of the opportunity to talk about something other than the run of the mill stuff they deal with to the trade every day.
I went with Cellulose from Jawel. 5 litres of high build primer, 5 litres of standard thinners, 5 litres of silver paint and 5 litres of gloss thinners came in at a little over £100 including delivery (via ebay). On Jawel's advice I gave the body a couple of coats of etch primer before laying on their high build primer.
I used a gravity fed gun (paint pot on top) with a 2.2mm nozzle for the high build primer, and a suction fed gun (paint pot beneath) with a 1.5mm nozzle for the etch primer and top coat. My compressor is a cheap 50 litre job rated at 1.5hp with an 8cfm output and it did the job well enough. I had to redo a couple of patches where I didn't quite get enough paint on, but that was more down to my lack of experience than the kit I was using. I'm pleased with the results and it wasn't as hard as I'd feared it would be.
Spraying your car is all part of the Sammio experience. I'd recommend it to anyone.
I agree with Towed, spraying is one of the best learning experiences of a Sammio build!
There are a few posts over on my build thread where I posted as i went that are worth a giggle at some of the things that went wrong for me.
In retrospect I'd say the biggest difference was adding an external water trap / regulator so that you get a more consistent pressure, it made a heck of a positive difference to me! I also tried both hvlp and suction spray guns and I settled on a cheepo suction one as I could get better results with it. But each to their own, and I'm sure by the time you're finished you'll know how you like to do it.
just be prepared for a LOT of sanding, filling,sanding,filling,flatting,filling <repeat as necessary>
