Paint Prep: Tips and Tricks

[Aussie Mike]

Hi All,

With all the talk about paintwork and body prep lately I thought it would be useful to start a thread where we can share skills and techniques we've picked up. We could also share info on products and materials we've found that work make the job easier.

This sort of info in one spot could help others tackling their paint prep or thinking about it.

Cheers

[stiffy]

My advice is to get a pro to do it.........

I have seen too many dissapointed people after they have spent $1000's of dollars and 1000's of hours with average results.

IMO the paint and trim (especially on a cobra) are the most important 2 factors to making a nice car. No one attempts their own interior so why do the paint.


my 2 cents worth


STIFFY

[Rebel1]

I disagree with Mr. Stiffy.

Many many cobra builders have never built a thing in their lives ... until the cobra.

The purchase of a Cobra kit is that one accepts they are going to do/make/build/fabricate/invent all manner of things quite foreign to most non trade folks.

It's a project, like building a boat/airplane/house and one should attempt whatever they want to fulfill their sense of achievement.

Like Stiffy, I have seen some horror stories. In most cases i find the horror also extends to what you cant see. ie. Suspension not refurbished, shocks and springs from the wrecking yard, poor drive train alignment, lousy wiring etc.

That just reflects the nature of the builder. Oftenwise, that builder is as proud of their creation as a builder with a triple digit showpiece.

On the other hand, I have seen some excellent work done by non practical/non-trade type folks( like school teachers) . It is just attention to detail and patience that is the key. Ohhh and ask heaps of questions.

I encourage folks to attempt the paint job. If after the first coat of primer one realizes it looks crappy, not much money is lost.

My hint for painting: Use a blunted hacksaw blade to apply bog to curved surfaces. Specially the tops of guards.

[hsv300]

I agree with both Stiffy and Rebel i personally would not try to do the paint but i think if the builder wants to have a go thats his decision.

[Aussie Mike]

Many times I've thought "Bugger this, I'm better off paying someone to do it" But then thought about the satisfaction from making a part or a mod that has worked out well.

Body work is just another challenge that requires learning a new set of skills. Unfortunately these skills are something you gain with practice not easily learned by reading a manual.

So If you have the time and patience why not give it a go. So you spend a couple of grand on materials and it all goes pear shaped, get a professional to paint it. It's easy enough to sand it all off. But if you have a go and have a win, hooray! you've learned some new skills and had fun doing it yourself and probably saved a bunch of money.

So back to the reason for this thread...

Les get your camera out and take a few pics of this hacksaw blade technique and share it with us. I'm certainly keen to learn.

I find a hacksaw blade just hand held is a usefull bodywork tool. It's good for scraping off the peaks and dags of filler as it's going off. It's usefull for trimming the edges of green fiberglass.

Cheers

[boxhead]

I will supply a tip that I have used and can vouch does work.
The fibreglass that most of our cars are made of is flexable, it can be heated with a heat gun (these can be bought at any hardware store) and you can "adjust" the body shape.
Example being my sills.
The R/H sill on my CR had more waves than Bondi beach, but over the period of 1 week, I systematically heated the sills and clamped long straight lengths of 4x2 timber to the inner and outer edges.
I did this each night when I got home from work and allowed the glass to cure and cool down over that night and the next day.
Here is a before picture,

Looks like I forgot to take some during the process, but you can see that toward the front the sill rolls under and tapers down alot, this is were it was very wavy.

I will be using the same process to push down the leading edges of the cockpit where they slide under the door, also I will attempt to put more curvature in the leading edge of the bonnet, it sits about 2mm low in the centre.

[Tenrocca]

Couple of things.....

Rage gold filler and KandH ultrafine gold as a good skimmer. AFS sanders - you can glue the paper on with spray adhesive (bostick one comes away easy enough) if you cant find self adhesive paper. I used Upol reface as a spray polyester and it is really nice and I actually liked the smell when sanded. Get a decent vapour mask when using fillers and resin - No smell makes it a lot more pleasant.

Panel gaps - lot of people glue paper to a thin piece of timber - I found this hard to use around curves so found a 3-4mm strip of rubber with paper glued both sides worked well.

Also if you really stuggling to get a planel flat when sanding back the filler (bonnet for me) spray a coat of polyester primer\surfacer. When the sandpaper cuts through the filler quicker then the surrounding gel coat it can make it tough, but an even coat of surfacer will help get it flat.

If you trying to get panel edges to line up, skim the whole area with filler, and when it starts to go off cut out the gap with a razor blade.

Cheers

[stiffy]

I should clarify my statement,


I HAVE NO TIME OR PATIENCE



STIFFY

[Rebel1]

Originally Posted by boxhead

I will supply a tip that I have used and can vouch does work.
The fibreglass that most of our cars are made of is flexable, it can be heated with a heat gun (these can be bought at any hardware store) and you can "adjust" the body shape.

Yep, totally agree boxhead....see this link:

Body prep

Some old codger recommended this to ya years ago.

Cheers

[Rebel1]

Another option for panel gaps and alignment.

3mm Klegecell, used in boat building is semi flexible and sands well. Use contact to glue it to the inside edge of the door jamb and have it extend past the side of the body and door panel. Run packing tape on the "parting" side of the foam. In in other words, Jamb it ( on edge) into the gap between the door/bonnet/any panel and the body.

Bog up to it on both the door and body sides and sand as required. Klegecell sands just like bog so you end up with a perfect 3mm gap and perfect alignment. The packing tape gives you a clean part line.

3mm is too thin for a panel gap but you can dress the edge to whatever you want.

Clean off contact residue with acetone.

[boxhead]

Originally Posted by Rebel1

Yep, totally agree boxhead....see this link:

Body prep

Some old codger recommended this to ya years ago.

Cheers

I had forgotten where that tip came from.
Well Les, it worked a treat.
And you can see how much of a bow was in the sill before I started in that other thread.

[Rebel1]

The main reason for that old post was to show your old pics and confirm how much fiberglass can be reworked.

I see many bonnets and boot lids which could be slightly reworked to proper alignment with a heat gun rather than using heaps of bog.

Every workshop should have a heat gun.

[stumpeater]

Great idea for a Thread Mike, and just in time for me too, you should add your hint about the 3M Dry Guide Coat.