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MG MGB Technical - wet sanding clear coat

I am picking up my Ol'Lady's 79 MGB form the paint shop today. From what the painter told me it has a primer/sealer, 2 coats of color and 5 coats of clear. He told me he puts 5 coats of clear for it could be wet sanded and buff after the clear dries.

The shop itself does not do the wet sanding and buffing after the paint dries. AND the people they recommend want $600 - $1000 to do it. If I do not think I can do it myself I will have to pay this. I do not want to screw up the new paint job. But if it is something I can do myself I would rather tackle it and save some money?

The issue is The person I talked to is now on vacation and the others there give me conflicting info on a few questions. I do not know what type of paint it is yet I will ask today when I pick it up.

SO

Is this a job someone that has never done it before can handle?

How long should I wait (letting the paint cure) before I wet sand?

What grade sand paper should I use to wet sand?

Any advice on the wet sanding process itself?

Now how about the buffing
I have a new in the box orbital buffer

What buffing compound is recommended?

Any advice on the buffing process itself?

RSF Bob Fowler

Bob, you should wet sand using Superfine Wet or Dry paper using soap until the surface is dead smooth and no orange peel is apparent. Then machine buff using Farecla G3 compound on a foam backing pad sprayed with a little water until a deep gloss appears. Take care on body folds for fear of breaking through but the whole process will take you many hours to complete somewhere about 10-12 hours probably. Mask everything that you dont want covered with this stuff as it is very difficult to remove once dried and wear very old clothes during the process
Iain MacKintosh

I learnt how to colour sand from a couple of web sites. These 2 are worth a look:-

http://www.mckennasgarage.com/xke/index.htm

http://www.camaros.net/techref/articles/JD%20Paint%20Article.pdf

The first one is a little OTT but the pictures and other stuff is good.

IIRC I used 1200 paper, wet, followed by 2000 paper, wet. Then I used 2 grades of Farecla compound either on my rotary polisher or by hand, G3 and G10.
David Witham

Just called the shop and they used a acrylic urethane. If that makes a difference.

Thanks I will look at this thread and the links more latter when I get the car back home
RSF Bob Fowler

FWIW, 3M make a variety of product, paper and various grades of compound for manual or power use, for this process and I got good advice from the local professional auto paint supplier.
Edd Weninger

Just got the car back. It looks great!!!. The manager of the paint shop said he did not recommend I wet sand it at all. He suggested I wait for 30 days then clean and wax it.

It does look real good the way it is so Maybe he's correct and I do not need to wet sand.

Other people I have talked to say to wait a couple months before waxing.

I am headed over to a high end paint supplier in the next couple days to see what they say and to pick up some good wax.

Any other suggestions are very welcome and much appreciated.

Thanks
Bob
RSF Bob Fowler

Colour sanding and compounding are sometimes called rectification. It is quite possible that they are very good with a spray gun so the straight from the gun finish is good enough for you.
David Witham

You can wax straight from the gun but the main purpose for wet sanding is to denib the surface and to establish that mirror finish which is seldom possible without rubbing. If I were you I'd try an experiment on a small portion of a panel and just see if it improves the finish enough to warrant a complete flat down and machine polish. You can of course skip the wet sand and machine polish only with G3 compound finishing with Hi Top to give the best possible result.
Iain MacKintosh

For buffing, sorry but leave the orbital in the box, and get a polisher, looks like an angle grinder, but goes much slower. You can pick one up new on eBay here is a uk one item 140104281939.

Get some G3 compund.

Start with a clean car (obviously!!) and work in the cool shade, early morning is best.

With a cloth, smear the G3 over the panel.
Attach the sponge, blue will be ok, cover up everything in line with the mop. Dip JUST THE MOP, not the electrics in water, and polish slowly. (you will get drenched, so will everything in sight)
The water is to cool the mop, keep dipping the mop in water. It will get very hot quickly. If it does, it will burn the paint.

Those orbital polishers are very hard work, any pressure to cut the paint and you just orbit round a stationary pad. No pressure and it wont cut into the paint.

Like Iain says, be careful at edges and points as it is easy to cut right through the paint. If your paintshop is good, you should only need a light cut to get a mirror finish, then hand wax. I cheat a bit and use a mild cutting polish (autoglym resin polish) to freshen up the paint followed by a sealer (autoglym high gloss. The autoglym will polish chrome and leave a slight film to resist corrosion too.
Martin Layton

If you are happy with the way the paint looks now, leave it alone. Just wax it when ready. If you decide to wet sand it use 1500 or 2000 grit wet. After sanding buff it out using 3M's Perfectit II followed by their swirl mark remover. Martin is correct, the only use for an orbital machine is waxing and polishing.
John H

I agree with John H, leave it alone. The gut wrenching sight of a burn through,will ruin your day.....for years.

Dont wax it until the paint has DRIED, stick your nose right down next to the paint,when you can no longer smell it, weeks...then its dry and set up.
wc wolcott

Before you risk anything, why not try a polisher on the family runabout and try to restore the "showroom finish"?

That way you learn how to do it, and improve the look of your shopping chariot.

It really isn't difficult, I got a very nice finish on my 'bike from a rather orange peely spray job with mine.

Martin Layton

Be very careful if you decide to practice on the family car, The automakersdon't put on one more drop of paint then needed
John H

Thanks all!!

I am happy with the way it looks now so I will not be wet sanding it.

Also I think I will take Martin's advice and practice one of my older cars first. It I screw it up I will not be as mad as if I screw up the MGB. And the Ol'Lady will not kill me!!

The manager at the paint shop told me to wash it today with Maguires auto was So I did. I followed the directions and use the right amount of soap and Cotton towels.

As I was cleaning it I noticed what seemed like a very slight oily film. I could wipe it off with my finger. I figured this was just residue from the clear coat? I do not think it was the soap. I rinsed the care several time and did not use that much soap in the first place.

Am I correct or could this be something else?
RSF Bob Fowler

fresh paint doesnt wipe off. fresh paint also doesnt require anything but water, SOFT WATER, hard water will permanently stain it if not immediately wiped off. Even if the shop put it in a bake oven,the paint is still gassing off,it is not set up yet.
wc wolcott

There won't be any residue from the clear coat but you might ask the body shop if they polished it when done. It's not unusual for a shop to polish a paint job when done as it will remove small nibs and imperfections , this is not to be confused with waxing.
If your paint looks great and has minimal orange peel you found both a good painter and the weather cooperated the day he shot it. The car manufactures only get the same quality paint jobs day after day because all of their paint systems are climate controled.
John H

Today I went out to work on the car and the Oily residue is gone. The car also looks shinier I'm not sure why!!

I do see some orange peal now. Not a lot though.

Is the orange peal removed by wet sanding or polishing/waxing. It its wet sanding I am not that concerned about the little bit of orange peal it has.

Today I started installing the sound deader mating. I will finish that up tomorrow then install the carpets.

Again than to everyone for your advise.

Bob
RSF Bob Fowler

Bob. Who did you use to paint your car. I am in Richmond.
D Enghauser

Bob I grew up in a body shop, and now have a restoration shop of my own, and I can tell you that if your happy with the way it looks now, then leave it alone. It is VERY easy to burn an edge on a B around the body line, and the fender/quarter beads if your not experienced with a buffer. If you want to attempt it err to the side of caution with every step, tape those edges w/good quality masking tape, and pay attention to the edge of the buffing pad(that's the part that will burn the paint, because it's moving the fastest). Even the guy at the paint store where I've been buying my paint was afraid to rub his car out after painting it, because just like the prep work, the final finishing can make or break a good paint job. I don't want to scare you, just better inform you, to protect your investment.
Robin Meier

I had it done at Earl Scheib's. But I had a friend that that had a relative that knew the owner. So when the owner called the manager he made sure my paint job was done right.

I seen some of the other paint jobs they did and was not to impresed but I was asured that mine would look better and it does.

RSF Bob Fowler

And it has a life time warranty!!!
RSF Bob Fowler

This thread was discussed between 12/04/2007 and 15/04/2007

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