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Peter D · 11-14-03, 12:42 AM

Thanks Pete - Yeah, the RTA are real pain in the A ! As for our State Premier, Bob Carr, who can't even drive one - what can I say (except that I didn't vote for the bastard !). No wonder all the good motoring events are in QLD, VIC or TAS.

Howard, the tool that I used more than anything was a simple Dremel, fitted with 60grit sanding drums - my first Dremel lasted until about a month ago, so now I am on No2 - worth their weight in gold ! They are perfect for trimming back the overhanging rough edges of glass that you have added to door edges, etc. (Some of these were up to 1/4" thick - no fun by hand).

Panel gap work will depend on how good or bad things are now. I found that the gap between the vertical front edge of the door & the front clip was the driver - it needed to be nearly 1/4" to allow clearance as the doors are opened. This meant that "Lexus Gaps" of around 1/16" would have looked out of place elsewhere, so I just made them all about the same as those front door edges. I also found that the bigger gaps allowed for having to shut the doors somewhat "firmly" to overcome the resistance of the door rubbers - at one stage I had 1/8" gaps around the door tops, but found that the "give" in the rubber allowed the doors to hit the roof before relaxing back to the correct position. Gaps of around 1/4" solved this problem.

If you need to build out door edges, etc, I found that the best way was to square off the edge with the Dremel, run one layer of glass over the edge (with about 1/4" overhang on each side), let it set & provide a wide base for the next layers, then run up to 6 layers at a time over this. I first tried 4 layers in one hit & ended up with them all falling on the floor ! If you need to build up an edge, and also the adjacent flat panel surface, I found it best to do the edge first, machine off the overhang, & then lay glass on the panel surface so that it crosses the new edge build-up - this way you get some "cross bonding" that adds a lot of strength to the bonds.

For rough body filing like shaping large areas of raw glass add-ons on panel faces, I started with 32grit on a flat stick or piece of exhaust pipe (for concave curves), then on to 80grit to get rid of the big scratch marks, then on to 120grit. All of this needs to be done with long diagonal strokes around the curves - never to-&-fro in the one area. I found that because of the flexibility of f/glass, I had to have the rubber seals in place around the doors & rear clip, and latches tensioned down, to hold everything in its final place while doing the body filing across the panel gaps.

With all that done (how easy were those words to write !), it is probably best to run a fairly heavy coat of spray polyester filler over the whole car. I made the mistake of running 4 light coats on & paid the price when we found hundreds of tiny pin-holes later on - I should have really wacked it on. The stuff is quite easy to sand back (nowhere near as bad a raw glass of gel-coat) & a 400grit finish is all you need before priming.

An important tip I learned from my Corvette expert is to never use water in the sanding processes on filler or primer - always use dry paper. The tiniest bit of water can stay in pin-holes for months, & will result in a humidity bubble in the final paint. The only downside to this is DUST - there will be bucket loads of it on you, the garage, the house, the neighbours, etc !! I figured that I put about $1,000 worth of filler over the car, & ended up with half of that floating around as dust.

My other big mistake was to wait for the expert to run a very light guide coat of GM Flat Black over the car - this is what showed up all the pin-holes, minor lumps & bumps, etc which are impossible to see when the car is in flat primer. If I had done that myself, I would have saved big bucks.

The car is up at the engine builder's now, so I can't get any pics until next week - I try some shots of the gaps as requested.
A whole weekend without the '40 to work on - I might have to re-learn how to start a lawn-mower !!!

More pics to follow next week.

Kind Regards,

Peter D.

11-14-03, 12:42 AM	#10 (permalink)
Peter D delaneyp Peter D Join Date: Sep 2001 Location: Sydney, Australia GT40: DRB #27 Posts: 1,238 Rep Power: 21	Re: GT40 Australia #27 Thanks Pete - Yeah, the RTA are real pain in the A ! As for our State Premier, Bob Carr, who can't even drive one - what can I say (except that I didn't vote for the bastard !). No wonder all the good motoring events are in QLD, VIC or TAS. Howard, the tool that I used more than anything was a simple Dremel, fitted with 60grit sanding drums - my first Dremel lasted until about a month ago, so now I am on No2 - worth their weight in gold ! They are perfect for trimming back the overhanging rough edges of glass that you have added to door edges, etc. (Some of these were up to 1/4" thick - no fun by hand). Panel gap work will depend on how good or bad things are now. I found that the gap between the vertical front edge of the door & the front clip was the driver - it needed to be nearly 1/4" to allow clearance as the doors are opened. This meant that "Lexus Gaps" of around 1/16" would have looked out of place elsewhere, so I just made them all about the same as those front door edges. I also found that the bigger gaps allowed for having to shut the doors somewhat "firmly" to overcome the resistance of the door rubbers - at one stage I had 1/8" gaps around the door tops, but found that the "give" in the rubber allowed the doors to hit the roof before relaxing back to the correct position. Gaps of around 1/4" solved this problem. If you need to build out door edges, etc, I found that the best way was to square off the edge with the Dremel, run one layer of glass over the edge (with about 1/4" overhang on each side), let it set & provide a wide base for the next layers, then run up to 6 layers at a time over this. I first tried 4 layers in one hit & ended up with them all falling on the floor ! If you need to build up an edge, and also the adjacent flat panel surface, I found it best to do the edge first, machine off the overhang, & then lay glass on the panel surface so that it crosses the new edge build-up - this way you get some "cross bonding" that adds a lot of strength to the bonds. For rough body filing like shaping large areas of raw glass add-ons on panel faces, I started with 32grit on a flat stick or piece of exhaust pipe (for concave curves), then on to 80grit to get rid of the big scratch marks, then on to 120grit. All of this needs to be done with long diagonal strokes around the curves - never to-&-fro in the one area. I found that because of the flexibility of f/glass, I had to have the rubber seals in place around the doors & rear clip, and latches tensioned down, to hold everything in its final place while doing the body filing across the panel gaps. With all that done (how easy were those words to write !), it is probably best to run a fairly heavy coat of spray polyester filler over the whole car. I made the mistake of running 4 light coats on & paid the price when we found hundreds of tiny pin-holes later on - I should have really wacked it on. The stuff is quite easy to sand back (nowhere near as bad a raw glass of gel-coat) & a 400grit finish is all you need before priming. An important tip I learned from my Corvette expert is to never use water in the sanding processes on filler or primer - always use dry paper. The tiniest bit of water can stay in pin-holes for months, & will result in a humidity bubble in the final paint. The only downside to this is DUST - there will be bucket loads of it on you, the garage, the house, the neighbours, etc !! I figured that I put about $1,000 worth of filler over the car, & ended up with half of that floating around as dust. My other big mistake was to wait for the expert to run a very light guide coat of GM Flat Black over the car - this is what showed up all the pin-holes, minor lumps & bumps, etc which are impossible to see when the car is in flat primer. If I had done that myself, I would have saved big bucks. The car is up at the engine builder's now, so I can't get any pics until next week - I try some shots of the gaps as requested. A whole weekend without the '40 to work on - I might have to re-learn how to start a lawn-mower !!! More pics to follow next week. Kind Regards, Peter D.