The Spray Painting Thread

["Z" UTE]

Andrew, if you are almost taking the paint back to starting point, you will get the bulk of the clear off faster by using 240 dry, 320 tends to clog fairly rapidly, and leaves bad scratch marks in newer paint.

So do the repairs, and prime them up, give everything a dry block back with 240, then a wet rub with 800. Do not forget to spray your guide coat, as the guide coat will show any areas that need to be reworked filled or reprimed. Being acrylic, you can give all the repair areas a quick coat of colour, then do the entire car in colour without too much of a break, the patches of black just have to flash off before the once over coat of black. Again just wait for flash off before applying the clear.

Try your spraying pressure and technique on a test piece, I have an old TA22 door, for that purpose, it must have 50 coats of paint on it by now. A half saecond pull on the spray gun trigger with the gun held about 200-250mm from the test piece should give you a elipse about 200mm high and about 35mm thick in the middle, the paint should almost be at the run stage, but not quite. When applying the paint to the car, position your gun at 90 deg to the panel again about 200-250mm off, squeeze your trigger before you actualy get to the panel, and release after you have reached the end of the panel, You must travel slow enough to get a wet film, but not so slow that the paint/clear runs. (you should practice this on your test panel) Your next pass has to overlap the previous pass by 50%. Your wrist must be locked in the straight ahead position, no rotating allowed, this way you maintain a constant angle and distance from the job, which results in a very even coverage of the panel.

When sanding use a long board, and sand at a diagonal from one edge to the opposite, then turn the board through 90 degrees and sand again edge to edge at the diagonal. ie. you are aiming for a "pommy flag", if you get my meaning.

If you have no long boards, use a piece of 40mm x18mm pine(Bunnigs always have it in stock, about $2-3 per metre), cut to the length of a sheet of sandpaper, round of the ends and corners with a qiuck rub with coarse sand paper. Wrap your 240-800 around the stick and go to town.

I have PM'd you my phone number, so if you get stuck or have a major problem give me a bell.

cheers Chuck.

[Jeri]

hi .. i've cut out the rust on the sills of my 22,, now that i have access inside the sills...

what would be the best option/ product to prevent any more rust in future???



thanks

Its been about 9-10 months, since i've touched my 22.... Bought a house in the last 8 weeks, and just brought the car to my new place 3 weeks ago.. Now its time to get stuck back into it, in between house renos...

My next step is to re-plate and fix all the rust cut outs, im thinking of buying a welder...

My question is...

is a gasless welder good enough to do the job?
I've found two

1) at repco MECHPRO Portable 100amp gasless mig welder for $299

2) at bunnings OZITO 90amp gasless mig welder for $299

Which one would be better?
If u guys could please help me or give me a few ideas, i really want to get this car finished this year.....

Thanks

["Z" UTE]

Gasless MIG welders are only good for rough as guts work. They suffer from limited temperature control, and spatter all over the shop. For the small amount you have to do, get a pro to do it, and dont waste your money on the gasless mig.

cheers Chuck.

[1JZ-Rolla]

agreed Chuck, there's only one place that I can think of where you'd want a gasless mig, and that's welding outside in the wind.

[pac]

you have to spend at least 6-7 hundred for descent gasless mig which you can add gas to anyway as long as you change the wire. if you not looking for a uniform weld gasless is fine for patches, spot welding and most car repair welds. remember you will grind down the weld anyway around the patch repair so doesn't matter on first apperance, they do the job and great for home use or small business

[o_man_ra23]

Question, is this the only purpose you will have for the MIG, or will you be welding everything you see like I do??

If it is the former, Chuck's advise of getting a pro to do it is the best option, it will probably be cheaper, will definitely be neater, and in the rocker sill where you have made a few incisions, it is structural, so the pro will do it stronger.

If you are going to weld a lot, the cheap MIGs you have suggested are a complete waste of money. They have extremely poor wire feed control, and the wire feeders after a month or so start sticking and cause your welds to look like bird shit. The cheapest MIG worth buying that I found was $900. It has served me well these past 3 1/2 years, and will continue to do so for many years to come.

[Steve M]

MIG welds are very brittle and prone to cracking if you have to grind them back flat like you would on a panel.

Cheap MIGs will require you to be good at filling holes with weld as you'll blow many of them due to lack on temperature control.

I've used a gas MIG (Transmig 135) with four setting plus wire feed control and that was difficult to get welding right on 0.7-0.8mm steel. It was about $700-800 from memory and it did do the job, but the new TIG machine we have does it much better (more $$ too though).

I've tried using gasless wire in the transmig and it was quite shit. I don't recommend it.

["Z" UTE]

Yes the normal MIG wire is quite hard, if you are repairing panels try something like silicone bronze, much softer, and requires less heat to melt and fuse to the panel, reduces the heat distortion in the panel you are repairing.

Switch back to the usual wire when doing structural work.

cheers Chuck.

[Steve M]

I wish I'd known about different fillers when I was doing panel work last, it would have made it much easier.

[o_man_ra23]

Heads to BOC in the morning for some silicone bronze wire in 0.6mm...

[Jeri]

Sounds like I'd be wasting my time by buying a gasless welder,
the thing is that i have a few more places to weld apart from the right hand side sill
(1 on roof, another small 1 on other sill, end of rear wheel arch completely gone, small bits on corners of rear and front windscreens)...

if i get it done by a pro how much would be the average price that some1 would charge?

or would it be better to get a gaswelder?


thanks guys for all your help.....

[Z2TT]

Well my painting went pretty crap, want to do the whole rear 1/4 now with a gun.

But question is, when I mask it off where the roof begins, and when I spray all my paint and then clear on, and remove the masking, there will be a huge line of new paint that is very higher than the original on the roof because of all the coats, like a visible line. Will the thinners melt this off ?

Or.

Is is the roof not supposed to be masked off so the paint lays itself on better at the blending point?
And then just sand away all the overspray and then shoot the clear? and then again sand off all the overspray from the clear?

Got no idea how am going to do it, whether to use tape or not.

Need help as I can't decide.

[o_man_ra23]

Jeri - depends on the business and how they feel on the day. I've had Aluminium work done for $70 cash, which was welding 4 items on, and cutting holes. If you make up the repair plates (ask the welder how they want them made, and use zincalume sheet, but you will need to grind off the zinc at the edges ever so lightly) and pay with folding stuff without a receipt, then you should get away with it fairly lightly.

["Z" UTE]

Z2TT, yup you will have a humungous step in the paint. Shops paint to the edge of a panel, or to a joint line that is normally covered with trim.

You will have to apply 3 masks to the car. Start out big, ie. mask around the area that will be your totally finished panel. Then mask a smaller area that will contain the colour onto the repair area. The third mask is the primed area. So paint your primer on, but do not build an edge at the tape, lightly sand the area to accept colour, remove that smaller mask. apply colour extending beyond the primer but do not form an edge of paint at the masking tape. Remove that mask, and spray your clear just beyond the colour, again do nort form a paint edge at the tape, remove the last mask, and apply a light coat of thinners, walk away have a cuppa or a frosty one and come back and marvel at your skills.

cheers Chuck.

[JZA70R_92]

a good trick is to apply the masking tape to your newspaper or whatever, the trick is put the newspaper over your panel your going to work on make sure masking tape is stuck well to the panel then flip it over. this will cause you to have a soft edge.