Fiberglass bumper question - another!
09-20-2015, 11:49 AM
#1
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Thread Starter
Fiberglass bumper question - another!
Good morning, all,
What do you do, if anything, to the back side of a fiberglass bumper?
I left my rear one untreated and it's been on for a year and the car has been driven some. I still have to fill and blend the outside (which is gel coated) which I'll do when the front is done, but now as I think about it, I'm wondering what to do with the backs of the bumpers, if anything.
Thanks!
Warmest regards,
Rob
What do you do, if anything, to the back side of a fiberglass bumper?
I left my rear one untreated and it's been on for a year and the car has been driven some. I still have to fill and blend the outside (which is gel coated) which I'll do when the front is done, but now as I think about it, I'm wondering what to do with the backs of the bumpers, if anything.
Thanks!
Warmest regards,
Rob
09-20-2015, 06:35 PM
#2
Race Director
Some people want me to shoot black paint on it so you do not see the sheen of the resin.
Outside of adding more resin and fiberglass mat to give the bumper more strength....that is all I generally do.
DUB
Outside of adding more resin and fiberglass mat to give the bumper more strength....that is all I generally do.
DUB
09-20-2015, 07:03 PM
#3
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Thread Starter
I have one more question for you, Dub. We're running out of warm enough weather here in Maine....once I get the bumper fitted using the Evercoat 870, should I seal it with anything until next spring when I can continue?
I'd like to be able to drive it enough this fall just to get the coolant circulated (I flushed the cooling system just before doing the bumper) and also to get a few minor mechanical things done before putting it up for the winter.
(YI...my painting experience is limited to shooting two part epoxy primer on aluminum and steel aircraft structure 23 years ago using a siphon feed Devilbiss JGA)
Thanks again, Dub.
All my best,
Rob
09-20-2015, 07:17 PM
#4
Race Director
YES...I would NOT allow the raw, exposed VPA to get contaminated. So...applying what ever product that you know you plan on using would be best.
OR...run your car with no bumper and not worry about what people think and wait until spring if you do not have time to do it correctly before you loose your 'window' of good weather.
If you plan on removing it...just keep it wrapped up if shop conditions are not the best...if not....blow off the dust and pull it into the house and find a safe spot for it.
DUB
OR...run your car with no bumper and not worry about what people think and wait until spring if you do not have time to do it correctly before you loose your 'window' of good weather.
If you plan on removing it...just keep it wrapped up if shop conditions are not the best...if not....blow off the dust and pull it into the house and find a safe spot for it.
DUB
09-20-2015, 09:08 PM
#5
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Thread Starter
Thanks once again, Dub!
I may have a chance to finish it if work schedule permits and weather holds. I was thinking an epoxy primer over the bumper and VBA, but I have NO idea what might be best.
I only say epoxy first to seal things up, but I have no idea what system to use, or what process to use. I'm going to try and do my block sanding on the VBA as best I can, but I suspect after epoxy I'll still need to fill or smooth stuff out as I'm a newbie.
By the way, Dub, what is a good color to use below paint? My car is orange.
I may have a chance to finish it if work schedule permits and weather holds. I was thinking an epoxy primer over the bumper and VBA, but I have NO idea what might be best.
I only say epoxy first to seal things up, but I have no idea what system to use, or what process to use. I'm going to try and do my block sanding on the VBA as best I can, but I suspect after epoxy I'll still need to fill or smooth stuff out as I'm a newbie.
By the way, Dub, what is a good color to use below paint? My car is orange.
09-21-2015, 05:56 PM
#6
Race Director
Epoxy primer will seal it up enough for you to put out on the road for a SHORT WHILE ....but DO NOT think that it is the 'be-all'...'end-all' providing protection to the bumper. It will work for a while.
After the epoxy primer you can sue a polyester primer which can fill in some surface defects and problems in minor body work issues. BUT...polyester primer DOES require a gun with a large enough fluid tip and nozzle (2.5 mm or larger) to apply it due to it being so thick. AND...this gun is mainly for it and 'generally' can not be used for painting the car. I wrote 'generally' because I could 'dial in and set-up' the gun and paint with it even though the fluid tip and nozzle are so large...and I know how to do this...AND I TEST 'things' before I pull the trigger on a panel. So investing in a special dedicated gun may not be in your scheme of things.
Other types of primers can be used also. They will not fill as quickly as a polyester primer....so more coats may be required....BUT ..usually the paint gun to shoot a 2K primer can be used for paint/clear if it is cleaned out and maintained.
AS for a color that will be what you shoot your orange on. Generally a light gray works well. A lot depends on how well the color covers and if it is really translucent or not....thus meaning that it is weak in pigments and can allow the undercoat to show through. Which then leads to me letting you know that if you are at the paint store and they have a 'spray-out card'....which is generally a black and white checkered card that allows you to shoot your color on it and see how many coats it takes to HIDE the checkers....thus letting you know when you achieve full hiding. AND...if you go that far and get one...just make sure that you paint it JUST LIKE you plan on painting the bumper...so do not soak the paint on and put double to triple coats on the spray out card...because that will give you a FALSE end result. Paint it just like you plan on painting the bumper.....proper flash times...proper overlap...travel speed of the gun, distance from the card when applying it, etc.
DUB
After the epoxy primer you can sue a polyester primer which can fill in some surface defects and problems in minor body work issues. BUT...polyester primer DOES require a gun with a large enough fluid tip and nozzle (2.5 mm or larger) to apply it due to it being so thick. AND...this gun is mainly for it and 'generally' can not be used for painting the car. I wrote 'generally' because I could 'dial in and set-up' the gun and paint with it even though the fluid tip and nozzle are so large...and I know how to do this...AND I TEST 'things' before I pull the trigger on a panel. So investing in a special dedicated gun may not be in your scheme of things.
Other types of primers can be used also. They will not fill as quickly as a polyester primer....so more coats may be required....BUT ..usually the paint gun to shoot a 2K primer can be used for paint/clear if it is cleaned out and maintained.
AS for a color that will be what you shoot your orange on. Generally a light gray works well. A lot depends on how well the color covers and if it is really translucent or not....thus meaning that it is weak in pigments and can allow the undercoat to show through. Which then leads to me letting you know that if you are at the paint store and they have a 'spray-out card'....which is generally a black and white checkered card that allows you to shoot your color on it and see how many coats it takes to HIDE the checkers....thus letting you know when you achieve full hiding. AND...if you go that far and get one...just make sure that you paint it JUST LIKE you plan on painting the bumper...so do not soak the paint on and put double to triple coats on the spray out card...because that will give you a FALSE end result. Paint it just like you plan on painting the bumper.....proper flash times...proper overlap...travel speed of the gun, distance from the card when applying it, etc.
DUB