Paint or Poly/Powdercoat?
Discussion
I have the rear subframe and rear suspension off my car for refurb at the moment. Cannot decide what process/surface finish to use.
Main concern is surface corrosion of the wishbones (subframe is much more chunky and solid), aesthetics, and longevity of finish (road car, will get stone chipped etc).
I was originally looking to replace the (14!) rubber bushes, however these all appear actually in good nick, and its a lot of money, so its not a definite. Options are -
- Powdercoating - Nice glossy finish, no guarantee of what's underneath the glossy polyester. Means I will HAVE to remove all bushes, adding a lot of arsing about and a LOT of cost. Not guaranteed to be that resilient to stone chips etc.
- Get the parts blasted, and paint myself. I think I should be able to get parts media/shot/soda blasted without removing the rubber bushes. Better guarantee of treating the rust. I can then paint with an etch primer or anti rust primer, and some sort of final finish (any recommendations?).
What do the classic drivers think?
Main concern is surface corrosion of the wishbones (subframe is much more chunky and solid), aesthetics, and longevity of finish (road car, will get stone chipped etc).
I was originally looking to replace the (14!) rubber bushes, however these all appear actually in good nick, and its a lot of money, so its not a definite. Options are -
- Powdercoating - Nice glossy finish, no guarantee of what's underneath the glossy polyester. Means I will HAVE to remove all bushes, adding a lot of arsing about and a LOT of cost. Not guaranteed to be that resilient to stone chips etc.
- Get the parts blasted, and paint myself. I think I should be able to get parts media/shot/soda blasted without removing the rubber bushes. Better guarantee of treating the rust. I can then paint with an etch primer or anti rust primer, and some sort of final finish (any recommendations?).
What do the classic drivers think?
I'm not sure why you seem to be comparing powder coating rust to painting de-rusted metal. Why wouldn't you de-rust before getting the parts powder coated?
Depending how much you find down the back of the sofa de-rust and powder coat should be the best long-term solution, as the electrostatic coating process will get in to every nook and cranny better than a liquid paint. You can also get semi-plastic finishes that will stand up better to stone chips. You would need to remove the bushes though as the powder has to be baked to turn it in to a permanent paint finish.
Depending how much you find down the back of the sofa de-rust and powder coat should be the best long-term solution, as the electrostatic coating process will get in to every nook and cranny better than a liquid paint. You can also get semi-plastic finishes that will stand up better to stone chips. You would need to remove the bushes though as the powder has to be baked to turn it in to a permanent paint finish.
//j17 said:
I'm not sure why you seem to be comparing powder coating rust to painting de-rusted metal. Why wouldn't you de-rust before getting the parts powder coated?
Depending how much you find down the back of the sofa de-rust and powder coat should be the best long-term solution, as the electrostatic coating process will get in to every nook and cranny better than a liquid paint. You can also get semi-plastic finishes that will stand up better to stone chips. You would need to remove the bushes though as the powder has to be baked to turn it in to a permanent paint finish.
Excellent practical advice. Given adequate preparation and rust removal on the item to be treated then powder coating with the plasticised coatings now available will be far more effective and long lasting than any paint. Simple choice really but quality preparation and rust removal prior to refinishing is essential for longevity even with powder coating. Good luck with the work given good preparation powder coating has a very long life IME. Certainly decades of protection.Depending how much you find down the back of the sofa de-rust and powder coat should be the best long-term solution, as the electrostatic coating process will get in to every nook and cranny better than a liquid paint. You can also get semi-plastic finishes that will stand up better to stone chips. You would need to remove the bushes though as the powder has to be baked to turn it in to a permanent paint finish.
I had my front subframe (on anothar car) powder coated, but for this one I'm looking at painting it instead. I don't have the first car, but the new owner has reported that there are some parts (edges, mainly) where the powder coating has chipped and it's quite difficult to do anything about that - if I've painted the part instead, I can just touch it up.
To be fair I mentioned it to the people who did the job and they said that it shouldn't get damaged, but we can't investigate further as the car is now too far away to return to them.
Whichever way you go, though, I'd recommend removing the bushes even if you decide to paint. How do you know what's lurking behind the bushes if you don't take them out? Usually the most time-consuming part is getting the vehicle into a state where the subframe can be removed, seems wrong to then do a quick job on the subframe after going to all that trouble.
To be fair I mentioned it to the people who did the job and they said that it shouldn't get damaged, but we can't investigate further as the car is now too far away to return to them.
Whichever way you go, though, I'd recommend removing the bushes even if you decide to paint. How do you know what's lurking behind the bushes if you don't take them out? Usually the most time-consuming part is getting the vehicle into a state where the subframe can be removed, seems wrong to then do a quick job on the subframe after going to all that trouble.
Have you moved house!?
Yes! Need to get this job completed then use it more. I'm a bugger for just using the first car out the drive, which means the Ma\da sits un-used for a while, and I'm constantly pissing about taking it to bits.
Anyway, thanks guys. There are some horror stories about piss-poor powdercoat but I guess that's the way to go, and use someone reputable.
Yes! Need to get this job completed then use it more. I'm a bugger for just using the first car out the drive, which means the Ma\da sits un-used for a while, and I'm constantly pissing about taking it to bits.
Anyway, thanks guys. There are some horror stories about piss-poor powdercoat but I guess that's the way to go, and use someone reputable.
droopsnoot said:
I Usually the most time-consuming part is getting the vehicle into a state where the subframe can be removed, seems wrong to then do a quick job on the subframe after going to all that trouble.
not quite - The whole lot (subframe, diff, wishbones, brakes, hubs) comes out with 4 nuts and 2 bolts.Its getting the bit apart and then getting the bushes out which is the lengthy bit!
I'd never powder coat suspension parts, subframes etc. One stone chip and there's a hole in the powder coating. Moisture creeps in and before winter is out, large flakes of powder coating are just waiting to fall off and reveal all that rust underneath.
The best longevity is achieved with fine media blasting, removing all rust etc. and leaving a fine etched surface. Then a couple of coats of a high zinc, self healing primer such as electrox is applied on the freshly blasted surface. Then a couple of coats of either 2k satin black or, if you prefer, an epoxy chassis paint to finish off. For belt and braces, coat the paint with a good clear underseal like Dynax. I have subframes treated like this that still look fresh after several years of hard use.
The best longevity is achieved with fine media blasting, removing all rust etc. and leaving a fine etched surface. Then a couple of coats of a high zinc, self healing primer such as electrox is applied on the freshly blasted surface. Then a couple of coats of either 2k satin black or, if you prefer, an epoxy chassis paint to finish off. For belt and braces, coat the paint with a good clear underseal like Dynax. I have subframes treated like this that still look fresh after several years of hard use.
Talkwrench said:
I'd never powder coat suspension parts, subframes etc. One stone chip and there's a hole in the powder coating. Moisture creeps in and before winter is out, large flakes of powder coating are just waiting to fall off and reveal all that rust underneath.
The best longevity is achieved with fine media blasting, removing all rust etc. and leaving a fine etched surface. Then a couple of coats of a high zinc, self healing primer such as electrox is applied on the freshly blasted surface. Then a couple of coats of either 2k satin black or, if you prefer, an epoxy chassis paint to finish off. For belt and braces, coat the paint with a good clear underseal like Dynax. I have subframes treated like this that still look fresh after several years of hard use.
This is the best advice on the thread IMO. I had all the suspension parts on my TR6 blasted, hot zinc sprayed, then epoxy painted and twenty years later they look just as good as when I bolted them on, and the car gets used year round. Powder coating is not good for suspension parts, or anything IMO.The best longevity is achieved with fine media blasting, removing all rust etc. and leaving a fine etched surface. Then a couple of coats of a high zinc, self healing primer such as electrox is applied on the freshly blasted surface. Then a couple of coats of either 2k satin black or, if you prefer, an epoxy chassis paint to finish off. For belt and braces, coat the paint with a good clear underseal like Dynax. I have subframes treated like this that still look fresh after several years of hard use.
Yertis said:
Talkwrench said:
I'd never powder coat suspension parts, subframes etc. One stone chip and there's a hole in the powder coating. Moisture creeps in and before winter is out, large flakes of powder coating are just waiting to fall off and reveal all that rust underneath.
The best longevity is achieved with fine media blasting, removing all rust etc. and leaving a fine etched surface. Then a couple of coats of a high zinc, self healing primer such as electrox is applied on the freshly blasted surface. Then a couple of coats of either 2k satin black or, if you prefer, an epoxy chassis paint to finish off. For belt and braces, coat the paint with a good clear underseal like Dynax. I have subframes treated like this that still look fresh after several years of hard use.
This is the best advice on the thread IMO. I had all the suspension parts on my TR6 blasted, hot zinc sprayed, then epoxy painted and twenty years later they look just as good as when I bolted them on, and the car gets used year round. Powder coating is not good for suspension parts, or anything IMO.The best longevity is achieved with fine media blasting, removing all rust etc. and leaving a fine etched surface. Then a couple of coats of a high zinc, self healing primer such as electrox is applied on the freshly blasted surface. Then a couple of coats of either 2k satin black or, if you prefer, an epoxy chassis paint to finish off. For belt and braces, coat the paint with a good clear underseal like Dynax. I have subframes treated like this that still look fresh after several years of hard use.
Ahonen said:
Yep, I agree. I've seen far too many horrors where the powder coat has chipped and lifted and wishbones/chassis tubes that look okay superficially have been completely rotten once you peel back the powder coating. Everything at risk on my car has been epoxy painted.
How's the RR coming along?If that's the Aldi-style £9.99 spot blaster, I'd recommend you get some different media. I've got a few of those and a proper blast gun (i.e. not trying to recycle the media), so I had to buy some media for the gun and tried it out in the spot blaster - was miles better than the stuff that comes in the box. As I recall it's silicate-free glass media, 25kg for about £15 delivered.
For parts of my subframe, I used the blast gun and put the subframe in a big plastic bag. I added a pipe as an exhaust, closed the rest of the open side up with clothes pegs and just stuck my gloved hand and the gun/pipe in through a small gap. I got some pretty good results, though it's hard to see after a very short time because of all the dust. A decent job, though, and pretty much for free. A mate kindly allows me to use his blast cabinet, but my subframe won't fit in it. I used the same approach on bits of the bodyshell - got another plastic bag, cut a hole in the top and taped it to the shell, stuck my arm in the other end with the blast gun, and blasted that way. Most of the grit was caught in the bag, some got out but much less clearing up to do.
When I use the spot blaster, I get a piece of closed-cell (or dense would do) foam, cut a hole in it and press that between the blaster nozzle and the panel - the hard plastic of the blaster doesn't seal very well so the grit still goes all over the place.
For parts of my subframe, I used the blast gun and put the subframe in a big plastic bag. I added a pipe as an exhaust, closed the rest of the open side up with clothes pegs and just stuck my gloved hand and the gun/pipe in through a small gap. I got some pretty good results, though it's hard to see after a very short time because of all the dust. A decent job, though, and pretty much for free. A mate kindly allows me to use his blast cabinet, but my subframe won't fit in it. I used the same approach on bits of the bodyshell - got another plastic bag, cut a hole in the top and taped it to the shell, stuck my arm in the other end with the blast gun, and blasted that way. Most of the grit was caught in the bag, some got out but much less clearing up to do.
When I use the spot blaster, I get a piece of closed-cell (or dense would do) foam, cut a hole in it and press that between the blaster nozzle and the panel - the hard plastic of the blaster doesn't seal very well so the grit still goes all over the place.
snotrag said:
Based on expected cost of costing, blasting etc. I've bought myself a small compressor, cheap paint gun and a spot blaster instead. Much more fun, and my time is free. Will clean up with flap wheels and spot blasting, and paint with decent primer and chassis black.
"Expected costs"??Who did you ask?
Talkwrench said:
snotrag said:
Based on expected cost of costing, blasting etc. I've bought myself a small compressor, cheap paint gun and a spot blaster instead. Much more fun, and my time is free. Will clean up with flap wheels and spot blasting, and paint with decent primer and chassis black.
"Expected costs"??Who did you ask?
Yertis said:
How's the RR coming along?
Getting there. No rush right now as I don't want to use it in the winter. Engine/box/suspension/doors/boot lid/rear bumper all bolted on. Aligning the front wings at the moment and just had to acquire a less rusty bonnet. The latest headache was realising that the tilt mechanism in the roof is so corroded that it's almost useless, so I'm on the hunt for parts again. It just never ends...Yertis said:
Talkwrench said:
I'd never powder coat suspension parts, subframes etc. One stone chip and there's a hole in the powder coating. Moisture creeps in and before winter is out, large flakes of powder coating are just waiting to fall off and reveal all that rust underneath.
The best longevity is achieved with fine media blasting, removing all rust etc. and leaving a fine etched surface. Then a couple of coats of a high zinc, self healing primer such as electrox is applied on the freshly blasted surface. Then a couple of coats of either 2k satin black or, if you prefer, an epoxy chassis paint to finish off. For belt and braces, coat the paint with a good clear underseal like Dynax. I have subframes treated like this that still look fresh after several years of hard use.
This is the best advice on the thread IMO. I had all the suspension parts on my TR6 blasted, hot zinc sprayed, then epoxy painted and twenty years later they look just as good as when I bolted them on, and the car gets used year round. Powder coating is not good for suspension parts, or anything IMO.The best longevity is achieved with fine media blasting, removing all rust etc. and leaving a fine etched surface. Then a couple of coats of a high zinc, self healing primer such as electrox is applied on the freshly blasted surface. Then a couple of coats of either 2k satin black or, if you prefer, an epoxy chassis paint to finish off. For belt and braces, coat the paint with a good clear underseal like Dynax. I have subframes treated like this that still look fresh after several years of hard use.
Thanks
Mr_B said:
Can I ask who did the work on your TR6 bits and if anyone else has a recommendation for someone to do the same, ideally someone as close to Dartford as poss.
Thanks
With pleasure. Unfortunately they're quite a way from you.Thanks
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