Paint removal.

PostPost by: john.houston » Wed Aug 09, 2006 10:37 pm

I have just taken delivery of my +2 project and have realised the first job must be to strip all the paint off ,down to the gel coat. I spent an hour with some wet and dry, and now have a dead arm! Can anyone advise how to remove the paint easily and safely. Many thanks, John
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PostPost by: ElliottN » Thu Aug 10, 2006 2:40 am

You'll get a fair bit of advice and some good tips no doubt but there's a lot of manual labour in getting to a good finish, so get down to the gym and start working on those biceps!
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PostPost by: alaric » Thu Aug 10, 2006 6:13 am

I'm not speaking from first hand experience but a common approach is to use an inch wide chisel (that's how my paint was removed) and accept that the gel coat is going to be damaged in the process. With a bit of practice this is apparently quite a quick approach. The gel coat will need completely repairing anyway.

Apparently chemicals can stay in the fibres, and a grinder can take off way too much too quickly and clog up.

Good luck.
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PostPost by: curly type 26 » Thu Aug 10, 2006 8:03 am

Wood chisel best method great stress releaver but be warned wear a pair of safety goggles/glasses because sooner or later yes youve guessed ouch! and the odd dig or two in gell coat wont matter and whilst you are doing this you can dream about finished car have fun Curly :D
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PostPost by: SADLOTUS » Thu Aug 10, 2006 8:36 pm

I've just marked off 60 hours on the garage wall like an Alcatraz prisoner, and still going, although not much left now. I used a 1/2" chisel, sharpened to a Samuri sharpness every ten minutes. very theraputic - for a while. Yes I also chipped the gelcoat a few times. seven coats down to the gel. On some places and the tricky areas I used the water soluble Nitromors in 6"-10" squares and only enough to get through each coat down to the undercoat, the Nitromors was easy to control at this size and with a bucket of water handy I could neutralise it quickly. Books and articles vary between using and not using Nitromors, I just tried to keep it under control and always washed down well afterwards. The bodywork/paint man said he uses it with no probs but then he's yet to paint mine. I'll let you know when the paints been on a year!
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PostPost by: john.houston » Thu Sep 14, 2006 10:42 pm

The chisel (very sharp) has worked.I have found that someone has beaton me to it .20 years ago someone stripped it but damaged the gelcoat (virtualy removing it)causing thousands of bubles in the paint due to trapped moisture in the strands expanding .The paint was a well applied job but just poor groundwork.What do I do to get a good base to work off ?? Still happy !!!
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PostPost by: carrierdave » Fri Sep 15, 2006 4:32 pm

I?ve just removed the paint from my car.
I have read many threads on the subject and all of the options have there associated problems and risk.
I chose to use a half inch or inch chisel along with a hot air gun. It takes a bit of practice but you apply a bit of heat to the area so that it becomes warm to the touch and then use the chisel to get under the layers of paint.

Obviously you need to be careful with the application of heat but I found that it made the paint more flexible. If you apply too much heat then the paint burns.

With just a chisel I found that the paint chipped too much leaving very small indents/holes in the gel coat and undercoat.

I also found that you could remove large areas on one go especially on the roof and bonnet.

Good luck

Dave
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PostPost by: purplepete » Sun Sep 17, 2006 2:08 am

I started out with an electric sander"just testing to see how difficult it was going to be"-the answer is..three afternoons,and its down to original grey primer,and theres an annoying film of red dust over every surface in the workshop!!
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PostPost by: cabc26b » Tue Sep 19, 2006 1:23 pm

I have strripped paint off of loti using two methods - Fiberglass safe chemical stripper ( Intersolv) with plastic scrappers that removed the paint and left the gelcoat intact ( was a S1 Europa circa 67 and had white gel coat applied) I did not keep thr car long enough after to verify the paint stick issue that some have mentioned - The whole process took about 40-50 hours using chemicals to strip - I am in the middle of sandding paint off an s1 elan ( circa 64) I am about 30 hrs into the job and have removed the top 2 layes of paint ( red/primer/darkblue/primer) and am working on the last layer ( medium blue ?) I scuffed the top layed with 100 grit on a random orbital , then went to 150 on the orbital to remove the top layers. I am now blocking with 150 and 220 . I suspect I will put another 30 hours into the sanding, so, much longer that using chemicals ( europa has a lot more surface)

I am not seeing the gelcoat like the europa, so am wondering if the early cars used it or not ( i remember reading somewhere that elirtes were not gel coated) ?
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PostPost by: tower of strength » Fri Oct 27, 2006 8:29 pm

I have spent the grand total of 8 hours scraping away at the black stuff in my engine bay with a sharp 1" chisel, and the theraputic aspect had past by the second hour. Then I tried 60grit in a small orbital sander, this was just as slow but gave a better finnish(less digs and nicks). A friend gave me a 3M Scotchbrite abrasive wheel, he uses these for paint removal on timber, and in 15minutes with an electric drill I have achieved more than in the previous 8 hours!! It lifts paint and old filler like you wouldnt believe , the down side is a scratched gel coat.seeing as I have micro blistering every where this is not such an issue for me as I'm going to have to reapply a resin coat to most of the car anyway. Using very light pressure hardly touches resin any how, so the damage is minimal!! I rekon the whole car can be stripped in less than a day with a couple of these :D . I'm reduced to scraping and sanding only in the tighter corners.

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PostPost by: john.houston » Fri Oct 27, 2006 10:29 pm

Hi Mark .Many weeks after this posting I am down to a bare shell .Pity I never got a chance to try that maybe the next one !!! So many helpful people have given me good advice. The process I intend to follow is
Fill every mark in the bodywork to my own satisfaction.
Get the body as hot as possible to dry out the moisture.
Prime using Polyeurethane 2 pk primer
At least 1 week later 2pk finnish.
I was told by my glass supplier not to redo gel as it would entail Resin A, tissue, Resin A again and then gel . The moisture content seems to be the trouble to sort. I even considered Epoxy and tissue but this job was daunting.. Have you ever put a gel coat on before ? I am still open to ideas.
:lol: Regards john
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PostPost by: tower of strength » Fri Oct 27, 2006 10:49 pm

Hi John,

I've only just started on the body shell after a few weeks on the chassis/gearbox. I'm being advised by a lecturer in car body repair techniques, he's currently running a two year course for GM (VX220) and Lotus repairers, His recomendation is to dry the shell out using infra red heaters (I've got a couple of floodlight style ones) then agressively sand the microblistered areas and coat with resin, on stress cracks he recomended grinding into the glass, then sesin, tissue and more sesin, filler to finish. My car has had a new nose that was poorly fitted (only bonded on the inner and outer wings) so I've had to grind out loads of old filler. Also the whole front of the car is delaminating, the grey gel coat has separated from the grp matting!!! so this must also be ground off and replaced. Unless I've got wrong information, a gel coat is merely a layer of resin applied to the mould that is allowed to "go off" prior to the matt being layed up with more resin. This ensures that the finished product when released from the mould has a smooth surface with no matt showing. Colour pigments can be added if desired to any resin layer. A friend who used to do grp mouldings often put different coloured pigments in his mouldings (usually black for the inside of wings and bonnets) and a different colour in the gel coat!!
To make my life easier I'm using cellulose high build primer in beige then 2K top coat. . . .. eventually!!!

If funds permit, i may pay a local body shop to put the top coats on for me to cut back at home.

Keep us posted of your progress!!

Mark
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PostPost by: reb53 » Sat Oct 28, 2006 9:01 am

Having made a few things in glass over the years my interpretation of "gel coat" is the same as that of Marks.

A coat of resin, sometimes coloured , is painted into the mould and when it has gone off sufficiently, clothe and mat lay-up can begin. This gives a resin coat on the surface without any danger of fiberglass strands being on the surface. If you don't wait long enough for it to go off this can happen. I would always wait until it was practically hard before starting to lay up the glass itself.

Merely painting resin onto a surface would leave a horrible looking sticky mess that seemed to take forever to harden, and if it eventually did was impossible to finish.

I've not done dozens of cars so can't speak from a position of great experience. However, the last car I did was 15 years ago and no stress cracks have yet appeared, the paint looking much the same as when it went on.

Once I had the paint off, using thinners, the extent of gelcoat cracks could be seen. These I drew along with a pencil to get an idea of how big an area needed doing. Looked a bit like a spiders web. Tried every sort of sander/grinder until settling on using the nose of a belt sander which allowed cutting through the cracked gel coat to the glass underneath.
Then one layer of resin/tissue followed by filler. NONE of the cracks have come back and we have some pretty rough roads over here.

Of all the fillers I tried an English one called Davids was the best as its hardness most closely approximated that of the original glass which meant sanding didn't result in hollows and bumps as did some of the others.

Ralph.
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PostPost by: john.houston » Sat Oct 28, 2006 11:13 am

Hi.Doug + Ralph. You have got me back to thinking about gel coat again.As I mentioned the glassfibre supplier was so possitve about not putting on a single gel coat .He was sure that a one off gel would not bond good enough and at some point it would "lift" .He said the only way was was to use tissue and laying up resin and then while tacky apply the gelcoat sort of doing the job in reverse.This would give strength and flexibility . What do you think??. The quality of my shell is like yours Doug nearly a bucket full of stuff .
Doug good shout on the infra red heaters thanks.
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PostPost by: reb53 » Sat Oct 28, 2006 8:47 pm

Hi John

I have never seen a satisfactory explanation of how you can paint resin back onto a fibreglass car and get a gel coat back again.

Even properly formulated thixotropic. non-sag resins that are made specifically as gel resins have the consistency of thick water.
This is OK when they are going on the inside of a mould and will be backed up with layers of clothe/mat but on the outside you'll end up with a dribbley, bumpy, brittle mess that you then have to somehow get a good surface on.
Even if it adheres properly I suspect it would still be brittle and crack prone with a pretty short life before you're back where you were.
I agree about the "one layer of tissue and then laying up resin".
After that I used a thin skim of body filler applied with a 30cm. steel ruler.
With not much practise you can get close to the finished contour in one sweep.

Did huge areas of the car like this including both doors in their entirety.
Finished with a standard one third sheet orbital sander.
The most critical thing I found in the whole job was the choice of filler.
If it is a lot harder than the surrounding glass it tends to not get as sanded and removed at the same rate which leaves it slightly proud and you have a gentle bump.

If it is softer it gets removed quicker and you get a hollow.
I suspect the majority of fillers are made for steel bodied cars where there would be less of a problem.

I don't know if the filler I used is still available but it turned out to be ideal.
It was English, called Davids with a number after it as they made a few types, ( including a chopped strand one that was useless).
I think the number was P38.

Have fun!

Ralph.
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