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I'm using an orbital sander to sand/strip the paint off my W25 fiberglass hood. I'm using 80 grit on the orbital and doing the flat spots. I will use just sandpaper to sand the edges and curves and valleys of the scoops and the nose by hand. I see 1 to 2 coats of paint and there is grey and black ? (maybe dark grey primer) on it and a white/light color layer which looks like it's an original finish on the hood when it was made.
I'm going to apply KONDAR red oxide primer when done. Before I do prime what grit sandpaper should I end up using. After the whole car is primed what grit should I use for the final sand before paint. I'm painting it with multiple coats of Duracryl lacquer with their High Performance clear for 2 or 3 final coats.
Since it's been over 20 years since I painted any car I'm still stressing over this last one!
I would also reconsider using a DA on the hood, even on the flat parts (other than maybe the top of the scoops). Get a set of good durablocks and block sand the hood by hand. Fiberglass can get wavy really fast if you are not careful. Personally, I would work to 220 grit, then use a high build 2K primer. Once cured, block with 220 - 400 using guide coat (re-prime/ skim as needed) Then after final prime, 400 dry followed by 600 wet before paint.
Last edited by Loaded68W34; July 8th, 2023 at 05:10 PM.
OK, I'll back off the 80 grit. The only other fiberglass I've worked on was my wife's Camaro and I put fiberglass front fenders and an L-88 hood on it. They were new items, so I scuffed them up and primed them with KONDAR!
Are the grits for the fiberglass the same for the metal body panels?
Thanks for the information so far. I should have finished this up but family, 2 jobs and getting old interrupted my motivation. I remembered what I was doing back then. Oh well, this will be the last one no matter how it turns out.
Are the grits for the fiberglass the same for the metal body panels
OLE442
Since fiberglass is obviously softer than metal, you just don't want to start as course. If you are going to use a DA, I would start with 120 grit or higher. If block sanding, you could start a little lower if you need to remove a lot of layers of paint.
If you have lots of experience with DA, then 80 grit shouldn't be a problem. If not, 80 by hand, finish with 180 with the DA, or hand. I would either Feather Fill it (being fiberglass), or a coat of epoxy followed by a high build primer. If high build, carefully hand block the primer, first with 220 or 320, then finish with 400 or 500, ready for paint. Might need more primer after the first blocking, though, as fiberglass is usually "ripple-y". If Feather Fill, start with a quick 180 cut, with a guide coat, then move up to higher grits, progressively.
The rule of thumb on sandpaper selection is 180 to take primer. 400 is fine for sealer or single stage paint, 600 for basecoat with no sealer and 800 for clear only.
I agree with others that I would not sand/strip a fiberglass hood with an orbital. It’s fine for pre-primer repairs, but I would use a block for all the sanding just to ensure it comes out straight. It can be done if you’re really experienced, but it’s a whole different ball game than stripping to metal.
If you have lots of experience with DA, then 80 grit shouldn't be a problem. If not, 80 by hand, finish with 180 with the DA, or hand. I would either Feather Fill it (being fiberglass), or a coat of epoxy followed by a high build primer. If high build, carefully hand block the primer, first with 220 or 320, then finish with 400 or 500, ready for paint. Might need more primer after the first blocking, though, as fiberglass is usually "ripple-y". If Feather Fill, start with a quick 180 cut, with a guide coat, then move up to higher grits, progressively.
Just curious what amount you would think I'd need to do just the W25 hood with Feather Fill? I only bought a quart since all that needs it would be the hood. It's a 47,700 actual mile Texas car. It has very, very little bodywork so I really don't need any there. I just hope that Feather Fill plays well with lacquer primer and paint.
The only car I ever had fisheye problems with was my wife's Camaro. I had to sand the whole car down and buy new urethane enamel and hardener to re-paint it with. I used fisheye additive that time. It came out very nice and shiny with only a small run that I took care of. Next, I painted an MGB-GT in lacquer using the same gun so I used fish-eye additive on that one since the gun was contaminated.
I have a Bink's 2001 siphon feed with an agitator cup that has never been used, a new Devilbiss Finish Line HVLP gun and a new AEROPRO HVLP SPRAY GUN G6600 HVLP gun! I've never used an HVLP gun so I was wondering if there will be any issues using one for metallic acrylic lacquer? Some on car forums say it will be an issue getting the flakes to flow out? Some say to thin down a bit the last color coat with lacquer thinner and it will flow everything out. What do you guys think.....which of these guns would you use for metallic lacquer paint?
Last edited by OLE442; July 19th, 2023 at 05:19 PM.
One quart of Feather fill is more than enough. 2 coats, with a good primer gun (minimum cap size of 1.8, 2.0 or 2.2 work MUCH better with Feather fil) If you have to thin it out to shoot it, put 3 coats on.
As for shooting lacquer, it's been a while, and I've never shot it with an HVLP gun. Just siphon guns. I'm sure there will be a learning curve with the HVLP's. Just be sure you don't put on too much material in one coat, as some HVLP's are likely to do. Screw in the fluid **** if you have to. lacquer should go on in thin coats, at least 6-8. Then sand with 600 a few days later, and to another 6-8 (esp. if using lacquer primer) There may be lots of shrinkage, and this will minimize it. Sanding and buffing is a breeze compared to today's paints.
I did a 53 Merc custom for a friend, in black nitro lacquer, but did it over a hi-build epoxy primer and had almost no shrinkage. Came out fanastic! You might reconsider using lacquer primer.
I have been sanding with a flat sander by hand with 150 grit! Below are the patterns I'm getting with the flat board on the top of the scoops. All but the nose of the hood appears to be only one layer of paint. On most of the hood there is the Viking Blue on top and below that is black of what I assume is a primer and a light or white below that (maybe a mold release??). I haven't hit anything that looks like fiberglass yet.
The nose has the blue and a med dark grey primer(?) over blue again and then the black and below that the white. The nose has a couple small spots that look like fiberglass. The looks like what may be body filler but very little and very thin.
So, what do you think about what this looks like after sanding. (see cell photos below) I'm just talking about the tops of the scoops because I'm still waiting for the 7 piece Dura Blocks to arrive to work between the scoops and other hard to work spots. If the whites are high spots, I really don't want to hit the fiberglass if I can help it but I'd like to remove all the blue paint before I Feather Fill!
I thought the whole car was a total repaint but I'm thinking most of it may be original. So far, most of it only has one layer of blue. It did have some bodywork on the passenger rear quarter. It really hasn't been on the street since the early 1980's and only has 47,700 actual miles. it has been garaged a lot of it's life since my brother brought it up from Houston.
I'm really stressing out about this paint job so I do appreciate your comments and info. I just wish I could find some info from some who have painted metallic lacquer with an HVLP gun.
OLE442
Last edited by OLE442; July 21st, 2023 at 01:46 AM.
You will find the right answers here. I have to say when you said 80 grit on that hood I was 😬 It's one thing if you have done plenty of them. Jumping in with 80 grit yikes 😬. Be patient. You will get the right answers here. I will say. My opinion don't keep sanding until you get the right answers. Take a breather.
Some say that if you leave any of the original lacquer paint and then spray Feather Fill over it, the FF will lift the paint. I have no idea if true but I'll be detail sanding the hood before I spray FF. Wonder about what looks to be a dark primer on the SMC? LOL! This OAI hood is causing me stress........
OLE442
Last edited by OLE442; August 10th, 2023 at 05:59 AM.
Reason: spellin
That is certainly a possibility(but not guaranteed to happen)any time you apply new material over a non-catalyzed material. What is certain is that any paint job is only as solid as its foundation and as strong as its weakest link. I would not want any lacquer left before I start building back with primer/filler.
20something years ago in paint school we did a demonstration where on Monday we prepped a metal panel and sealed half with 2k and half with 1k. Then painted the whole thing with base and clear as normal. That friday they had us take our panels and pour lacquer thinner on them. The side with the 1k sealer blistered up almost immediately. The side with 2k sealer was able to be wiped off and polished as though nothing happened.
Having lacquer under all your new hard work would yield a similar result. It might look fine when you’re done, but after some time, or maybe a little gas gets on it, you’ll regret it.
Last edited by ijasond; August 10th, 2023 at 10:36 AM.
So.....even the dark original primer would need to be removed? This is getting to be a PITA!
Be a shame to remove the W25 hood and the OAI air cleaner and make this one original OAI car that was turned into a non OAI car! The opposite of the normal trend.
I'm really not thrilled with the Feather Fill. Might just go KONDAR all the way and whatever happens....happens. In the past KONDAR has been a good high build primer. I'm really perturbed.
So.....even the dark original primer would need to be removed? This is getting to be a PITA!
Be a shame to remove the W25 hood and the OAI air cleaner and make this one original OAI car that was turned into a non OAI car! The opposite of the normal trend.
I'm really not thrilled with the Feather Fill. Might just go KONDAR all the way and whatever happens....happens. In the past KONDAR has been a good high build primer. I'm really perturbed.
Personally I’d take it down to the gel coat and hit it with high build primer or feather fill, but I do this for a living so that’s like an hours worth of work for me. It’s the blocking/priming/prepping after that where you want to spend the quality time.
Ok, I sprayed all my guns today with lacquer thinner. I bought a quart of Viking Blue lacquer from TCP Global to waste on spraying panels for each gun to see what works best.
I have an old DeVilbiss MBC siphon feed gun I've had for years and have used for primer. The tip/rod for it is a No. 30. What does that compare to in todays sizes?
I'll still probably use that for primer. It's an old, old gun.....I sold off 2 DeVilbiss JGA guns years ago!
The Bink's 2001 with the agitator cup is neat. It's new but has sat since the early 1990's but seems to work fine. Neat concept but I'll probably not use it since the HVLP guns will have less overspray/less wasted paint! It does have a 66SD tip/rod......not sure what that equates to in todays size. Anyone have a clue??
I have a NOS Devilbiss Finish Line marked E-05 that I'm considering. Seems to spray nicely with just thinner. It has a 1.3 and I believe a 1.8.
I also have the AEROPRO HVLP SPRAY GUN G6600 HVLP gun. It seems to spray well with the thinner.
Tommorrow or Sunday, I'll spray out the test panels with color. We shall see.
Last edited by OLE442; August 10th, 2023 at 04:58 PM.
Reason: correction
I've got probably $10k worth of paint guns in my closet and my day-to-day go to is the Devilbiss GPG 7E7. It's a very affordable gun by professional standards and is in my opinion the most versatile gun on the market. It would be my recommendation for anyone looking to purchase a pro grade, yet affordable gun.
However, I also have harbor Freight guns. Their Spectrum is actually a really nice gun. I also have their purple gun, which sells for around $20. I can get you a nice finish out of any of them, just as I could with any of the guns you posted, assuming they are in working order.
I learned on a Binks #7. Transfer efficiency has supposedly improved leaps and bounds over the years, but in reality, the amount of paint I need to do jobs really hasn't changed that much. The guns have adapted to the materials while also having to meet strict and pointless government requirements. It has not been a smooth process. If I could, I would use the guns I was using before the EPA ruined it. As a hobbyist, you can do that. I can't or I'll go to EPA jail.
My worthless two cents...
'I' would never DA a fiberglass hood to strip it. Use a chemical stripper...and keep your eyes on it. Don't let it penetrate for too long. The new non toxic strippers work slower and effective. I have stripped many Corvettes and Shelby fiberglass body parts since the 1980s. Do NOT penetrate the gel coat if possible.
My worthless two cents...
'I' would never DA a fiberglass hood to strip it. Use a chemical stripper...and keep your eyes on it. Don't let it penetrate for too long. The new non toxic strippers work slower and effective. I have stripped many Corvettes and Shelby fiberglass body parts since the 1980s. Do NOT penetrate the gel coat if possible.
As a lifelong professional painter, I will always choose mechanical stripping over chemical. Stripper is for furniture, and airplanes because they aren’t allowed to be stripped mechanically.
Even if you wanted to chemically strip you can’t any more. The epa fairly recently banned the active ingredient in paint stripper and if you buy some now you will find that it does not work.
As a lifelong professional painter, I will always choose mechanical stripping over chemical. Stripper is for furniture, and airplanes because they aren’t allowed to be stripped mechanically.
Even if you wanted to chemically strip you can’t any more. The epa fairly recently banned the active ingredient in paint stripper and if you buy some now you will find that it does not work.
Not correct. Paint stripper is available. I just used it. It now has no harsh smell, (see picture) and takes longer to do the job as the 'older' pre-EPA stuff. IF you wish to DA fiberglass to remove layers of paint, that is your choice. And, btw I also have been doing paint and body work for over 30 years.
Last edited by crossboss; September 17th, 2023 at 09:03 AM.
Reason: typo
My worthless two cents...
'I' would never DA a fiberglass hood to strip it. Use a chemical stripper...and keep your eyes on it. Don't let it penetrate for too long. The new non toxic strippers work slower and effective. I have stripped many Corvettes and Shelby fiberglass body parts since the 1980s.Do NOT penetrate the gel coat if possible.
Well, from what others on this forum and other forums have told me these hoods are not made of "traditional" type fiberglass. It is made from a fiberglass material called SMC. From what has been said, it does not have an actual gel coat and my work on this piece gives me that indication. When I sanded it, there was the thin Viking Blue top color, a thin primer coat, a thin black primer coat and then a white material (which appears to be the SMC)! I would assume that the SMC is all white from there on in. So.....where I am is where I am and I can't change my previous actions. I have dealt with many fiberglass pieces in the past and never dealt with SMC! The hood is really a hard thing to think of since it weighs (as I've been told) about 40 lbs. more than a stock steel hood! No weight savings here but I suspect that the SMC was the easiest, cheapest way for them to produce the W25 hoods! The whole one-piece front end on my 65 MUSTANG Fastback back-in-the-day didn't weigh as much as just the W25 hood IIRC!
Working on the whole car, I believe that 60 to 75 percent of the car was the original finish. The passenger side had had some body work done to it in places and a lot of that side has additional paint work done to it. I always have thought that the whole car had had a repaint before my brother bought it in the 1980's. Had I known it was more original paint I may have proceeded differently.
As far as the stripper, I used "Aircraft Stripper" BITD to strip my BOSS 302 and it was some nasty ****! It worked well but you had to keep it away from seams and places where it could remain. I used black lab type rubber gloves and it still would burn my fingers through them. Later, because using steel wool with the gloves was cumbersome, I stopped using the glove and did it bare handed. It was faster and none of my nails or skin came off! Surprising I'm still alive! LOL! I had no desire to ever use that again on a car.
Any rate, I'm using KONDAR on the whole car and hope the finish product looks as presentable as the other cars I did back then. It will be what it will be. If it looks nice, I'll drive it BUT, if it looks subpar, I will drive it any freakin' way cause at 71, I just don't want to do it over. I don't figure I'll make it to 80 so it's not as important as it was when I was 35! Just doing the best I can with what I've got!
BTW, I've been doing bodywork/paint since I was a very early teen (helping my Dad turn a buck on cars to get extra money for the family). Nothing professional but I've done quite a few. Once I thought of doing it as a living but the first car i did for someone turned out on the lower end of the "just OK" result. I did a lot of collision work for a really cheap price"! When I gave him his car, I told him "I'll give you all your money back if you let me have it alone for 10 minutes with a baseball bat"! LOL
Last edited by OLE442; September 17th, 2023 at 11:42 AM.
Reason: added text
As a lifelong professional painter, I will always choose mechanical stripping over chemical. Stripper is for furniture, and airplanes because they aren’t allowed to be stripped mechanically.
Even if you wanted to chemically strip you can’t any more. The epa fairly recently banned the active ingredient in paint stripper and if you buy some now you will find that it does not work.
crossboss:
He never said you couldn't get stripper......not just the good formulas like way back when.
It's like the new vs the old DAP/Weldwood contact cements! They have a new environmental friendly one and still sell the original formula too. The old one works better and I only use that one.
IMO, the EPA is a full of sh*t organization and are the folks who gave us that POS gas can with the special spout valve "to save the atmosphere"! Well, the new spout vents as much fumes into the air and, from my experience, causes you to spill more actual gasoline. I have quite a few and have noticed that the plastic/metal valve comes apart after a few years and don't do what they're supposed to do!
I'm planning on checking out garage sales to try to find pre-EPA gas cans since I keep 75 to 80 gallons of gasoline on hand for emergencies. Yes, I use Sta-Bil and rotate it every year.
He never said you couldn't get stripper......not just the good formulas like way back when.
It's like the new vs the old DAP/Weldwood contact cements! They have a new environmental friendly one and still sell the original formula too. The old one works better and I only use that one.
IMO, the EPA is a full of sh*t organization and are the folks who gave us that POS gas can with the special spout valve "to save the atmosphere"! Well, the new spout vents as much fumes into the air and, from my experience, causes you to spill more actual gasoline. I have quite a few and have noticed that the plastic/metal valve comes apart after a few years and don't do what they're supposed to do!
I'm planning on checking out garage sales to try to find pre-EPA gas cans since I keep 75 to 80 gallons of gasoline on hand for emergencies. Yes, I use Sta-Bil and rotate it every year.
Well, from what others on this forum and other forums have told me these hoods are not made of "traditional" type fiberglass. It is made from a fiberglass material called SMC. From what has been said, it does not have an actual gel coat and my work on this piece gives me that indication. When I sanded it, there was the thin Viking Blue top color, a thin primer coat, a thin black primer coat and then a white material (which appears to be the SMC)! I would assume that the SMC is all white from there on in. So.....where I am is where I am and I can't change my previous actions. I have dealt with many fiberglass pieces in the past and never dealt with SMC! The hood is really a hard thing to think of since it weighs (as I've been told) about 40 lbs. more than a stock steel hood! No weight savings here but I suspect that the SMC was the easiest, cheapest way for them to produce the W25 hoods! The whole one-piece front end on my 65 MUSTANG Fastback back-in-the-day didn't weigh as much as just the W25 hood IIRC!
Working on the whole car, I believe that 60 to 75 percent of the car was the original finish. The passenger side had had some body work done to it in places and a lot of that side has additional paint work done to it. I always have thought that the whole car had had a repaint before my brother bought it in the 1980's. Had I known it was more original paint I may have proceeded differently.
As far as the stripper, I used "Aircraft Stripper" BITD to strip my BOSS 302 and it was some nasty ****! It worked well but you had to keep it away from seams and places where it could remain. I used black lab type rubber gloves and it still would burn my fingers through them. Later, because using steel wool with the gloves was cumbersome, I stopped using the glove and did it bare handed. It was faster and none of my nails or skin came off! Surprising I'm still alive! LOL! I had no desire to ever use that again on a car.
Any rate, I'm using KONDAR on the whole car and hope the finish product looks as presentable as the other cars I did back then. It will be what it will be. If it looks nice, I'll drive it BUT, if it looks subpar, I will drive it any freakin' way cause at 71, I just don't want to do it over. I don't figure I'll make it to 80 so it's not as important as it was when I was 35! Just doing the best I can with what I've got!
BTW, I've been doing bodywork/paint since I was a very early teen (helping my Dad turn a buck on cars to get extra money for the family). Nothing professional but I've done quite a few. Once I thought of doing it as a living but the first car i did for someone turned out on the lower end of the "just OK" result. I did a lot of collision work for a really cheap price"! When I gave him his car, I told him "I'll give you all your money back if you let me have it alone for 10 minutes with a baseball bat"! LOL
The OEMs like W25 hoods and later Shelby fiberglass, they are actually injected molded 'fiberglass reinforced plastic' is the official term. AO Smith made the 'glass for Shelby and Chevrolet Corvettes. Aftermarket items are more or less hand laid or chopper gun fiberglass. This is the cheaper way. 'Some' of the OEM 'glass is also bonded to steel frames for better quality/fitment.
He never said you couldn't get stripper......not just the good formulas like way back when.
It's like the new vs the old DAP/Weldwood contact cements! They have a new environmental friendly one and still sell the original formula too. The old one works better and I only use that one.
IMO, the EPA is a full of sh*t organization and are the folks who gave us that POS gas can with the special spout valve "to save the atmosphere"! Well, the new spout vents as much fumes into the air and, from my experience, causes you to spill more actual gasoline. I have quite a few and have noticed that the plastic/metal valve comes apart after a few years and don't do what they're supposed to do!
I'm planning on checking out garage sales to try to find pre-EPA gas cans since I keep 75 to 80 gallons of gasoline on hand for emergencies. Yes, I use Sta-Bil and rotate it every year.
Some people hear the word fiberglass and immediately insist that it must be gelcoat. It’s strange to me, but I’m used to it. I’ve seen it all my life.
I agree about the EPA, along with most other 3 letter agencies. For a large portion of my career in the auto body industry I was tasked with maintaining gov compliance across multiple shops. Talk about a PITA at times.
For your gas cans, you can go online and buy vents and flex spouts. Drill a hole, pop in a vent and voila, pre-epa gas can. I have them in all of mine.
Gas Can Spout Replacement Improved Design Flexible Pour Nozzle Kit with Gasket Stopper Vent Cap Collar Caps for Old Style Water Gas Container Jug Pack of 3 https://a.co/d/5w81DrC
July 8th, 2023, 04:23 PM
