Original Chassis Colour
Discussion
Interesting as I hadn't come across hot zinc spray before.
A bit of research and It may be a better alternative to power coat and also there is no risk of heat distortion which there is with hot dip galvanizing. It is apparently easy to paint over unlike HDG.
On the down side it is only 25-33% as effective at preventing corrosion as hot dip galvanizing at 17-22 year protection where as HDG provides 50-75 years. The other downside appears to be that it is approx 40% as hard as HDG which makes it less hard than the base steel. Therefore it will chip from impact damage where as HDG is harder than the base steel and therefore the protection is not affected from chipping, scratching or other impacts.
This data/info sheet is quite informative. It would be nice to see powder coating included in the comparison.
https://galvanizeit.org/uploads/publications/Galva...
Moto
A bit of research and It may be a better alternative to power coat and also there is no risk of heat distortion which there is with hot dip galvanizing. It is apparently easy to paint over unlike HDG.
On the down side it is only 25-33% as effective at preventing corrosion as hot dip galvanizing at 17-22 year protection where as HDG provides 50-75 years. The other downside appears to be that it is approx 40% as hard as HDG which makes it less hard than the base steel. Therefore it will chip from impact damage where as HDG is harder than the base steel and therefore the protection is not affected from chipping, scratching or other impacts.
This data/info sheet is quite informative. It would be nice to see powder coating included in the comparison.
https://galvanizeit.org/uploads/publications/Galva...
Moto
Moto said:
Interesting as I hadn't come across hot zinc spray before.
A bit of research and It may be a better alternative to power coat and also there is no risk of heat distortion which there is with hot dip galvanizing. It is apparently easy to paint over unlike HDG.
On the down side it is only 25-33% as effective at preventing corrosion as hot dip galvanizing at 17-22 year protection where as HDG provides 50-75 years. The other downside appears to be that it is approx 40% as hard as HDG which makes it less hard than the base steel. Therefore it will chip from impact damage where as HDG is harder than the base steel and therefore the protection is not affected from chipping, scratching or other impacts.
This data/info sheet is quite informative. It would be nice to see powder coating included in the comparison.
https://galvanizeit.org/uploads/publications/Galva...
Moto
I've seen mixed reports over the compared effectiveness, to be honest. During salt-spray tests, the thermal spray was actually more resistant than the HDP in some cases.A bit of research and It may be a better alternative to power coat and also there is no risk of heat distortion which there is with hot dip galvanizing. It is apparently easy to paint over unlike HDG.
On the down side it is only 25-33% as effective at preventing corrosion as hot dip galvanizing at 17-22 year protection where as HDG provides 50-75 years. The other downside appears to be that it is approx 40% as hard as HDG which makes it less hard than the base steel. Therefore it will chip from impact damage where as HDG is harder than the base steel and therefore the protection is not affected from chipping, scratching or other impacts.
This data/info sheet is quite informative. It would be nice to see powder coating included in the comparison.
https://galvanizeit.org/uploads/publications/Galva...
Moto
Regarding hardness, I've never seen it remove from the surface, and I've done quite a few chassis' (at a guess, around 40 or so). If a coating is too hard, I'd be worried about it being too brittle, and fracturing with the flex of the chassis, personally.
The downside of HZS is that you only have a limited window before you have to seal it with a primer of some sort.
However, I think people are suggesting this as an alternative to painting. I certainly wouldn't! Our chassis' are hot-zinc sprayed, epoxy primed, epoxy 2k wet sprayed, and then overcoating in the most vulnerable areas with 2k epoxy mastic. In the past we'd have zinc'd chassis' powdercoated, but it's difficult to do, and with no cost saving because of the increased labour. And if powder coat isn't the cheaper option, what's the point?
Kitchski said:
Moto said:
Interesting as I hadn't come across hot zinc spray before.
A bit of research and It may be a better alternative to power coat and also there is no risk of heat distortion which there is with hot dip galvanizing. It is apparently easy to paint over unlike HDG.
On the down side it is only 25-33% as effective at preventing corrosion as hot dip galvanizing at 17-22 year protection where as HDG provides 50-75 years. The other downside appears to be that it is approx 40% as hard as HDG which makes it less hard than the base steel. Therefore it will chip from impact damage where as HDG is harder than the base steel and therefore the protection is not affected from chipping, scratching or other impacts.
This data/info sheet is quite informative. It would be nice to see powder coating included in the comparison.
https://galvanizeit.org/uploads/publications/Galva...
Moto
I've seen mixed reports over the compared effectiveness, to be honest. During salt-spray tests, the thermal spray was actually more resistant than the HDP in some cases.A bit of research and It may be a better alternative to power coat and also there is no risk of heat distortion which there is with hot dip galvanizing. It is apparently easy to paint over unlike HDG.
On the down side it is only 25-33% as effective at preventing corrosion as hot dip galvanizing at 17-22 year protection where as HDG provides 50-75 years. The other downside appears to be that it is approx 40% as hard as HDG which makes it less hard than the base steel. Therefore it will chip from impact damage where as HDG is harder than the base steel and therefore the protection is not affected from chipping, scratching or other impacts.
This data/info sheet is quite informative. It would be nice to see powder coating included in the comparison.
https://galvanizeit.org/uploads/publications/Galva...
Moto
Regarding hardness, I've never seen it remove from the surface, and I've done quite a few chassis' (at a guess, around 40 or so). If a coating is too hard, I'd be worried about it being too brittle, and fracturing with the flex of the chassis, personally.
The downside of HZS is that you only have a limited window before you have to seal it with a primer of some sort.
However, I think people are suggesting this as an alternative to painting. I certainly wouldn't! Our chassis' are hot-zinc sprayed, epoxy primed, epoxy 2k wet sprayed, and then overcoating in the most vulnerable areas with 2k epoxy mastic. In the past we'd have zinc'd chassis' powdercoated, but it's difficult to do, and with no cost saving because of the increased labour. And if powder coat isn't the cheaper option, what's the point?
N.
I regularly see HDG bolts corroded badly after 10-15 years to the point they need replacement. It’s not magic and depends on the environment. TSA is not without its problems either...
Overkill perhaps, but it’s whats being used in favour of HDG in a number of applications.
http://nano.elcosh.org/index.php?module=NanoProduc...
Overkill perhaps, but it’s whats being used in favour of HDG in a number of applications.
http://nano.elcosh.org/index.php?module=NanoProduc...
Edited by anonymous-user on Friday 21st June 10:08
You know it is funny but we see all this talk of various coatings to go onto a car which lasted 30 - 40 years prior to restoration which was given a couple of coats of Chassis black coach enamel on rusty tubes extracted from the old Hoo Hill brick kilns.... Makes me giggle!!
Proper powder coat is a great finish, so is Metal spraying ( note I said metal spraying) Galvanizing can be done but a lot of galvanisers are used to doing heavy gates and railings so be very careful who you would trust to do it... It also adds significantly to weight!!.. especially on open chassid box sections... Similarly a good blast with a nice media prior to a good zinc rich primer and epoxy top coat is also a good finish......
I am approaching 50 and with all the coatings available not really that concerned about how long the car may last when I am 6ft under
. Just how long do you want these things to last?? 
Even aerosols today are leagues ahead of anything available back then.. with the exception perhaps of lead The fundamental though is the coating time between the final blast and the top coats... If this is not done in the same facility then all your stages will not matter one jot.
N.
Proper powder coat is a great finish, so is Metal spraying ( note I said metal spraying) Galvanizing can be done but a lot of galvanisers are used to doing heavy gates and railings so be very careful who you would trust to do it... It also adds significantly to weight!!.. especially on open chassid box sections... Similarly a good blast with a nice media prior to a good zinc rich primer and epoxy top coat is also a good finish......
I am approaching 50 and with all the coatings available not really that concerned about how long the car may last when I am 6ft under
. Just how long do you want these things to last?? Even aerosols today are leagues ahead of anything available back then.. with the exception perhaps of lead The fundamental though is the coating time between the final blast and the top coats... If this is not done in the same facility then all your stages will not matter one jot.N.
TVRMs said:
I’d just like mine to last as long as I expected it to when I had it applied
Original coating good, not all Neil. Our Vixen S3, at the ripe old age of 8 years old, required new outriggers due to being corroded through...?
I am amazed any of your cars get rusty with the polishing you do underneath.... Original coating good, not all Neil. Our Vixen S3, at the ripe old age of 8 years old, required new outriggers due to being corroded through...?
Edited by TVRMs on Friday 21st June 13:59
All options are good.. but as said the failure of any coating is the result of what the 1st coat is applied to.. any subsequent coats are only adhering to the first one In my book the chassis must come straight out of the blast and then go straight in the oven then be 1st coated immediately.. The powder coating I get done can be hit with a hammer and it doesn't chip, flake or crack :-) as with everything it matters how good it is and who is doing it... Show finish work would be a 2 pack epoxy paint finish for the sheen that you don't get with a powder.. softer though and needs to be kept on top of. Metal spraying is porous and still needs a suitable top coat.... and Galvanising well... maybe for farm gates 
N.
My experience with powder coat wasn't great. It was back in the early 90's mind so things have probably progressed but it split around the tubes closest to the exhaust manifolds within 2 years, presumably due to heat and it soon started to peel away. Very annoying after the effort & cost of having a full chassis rebuild.
At work we run a around 20 Ifor Williams HDG trailers. I can honestly say I've never had any rust appear even when the galvanizing gets worn through from winch cables rubbing, gravel and rubble being dropped in and tipped out day after day or getting dinged by a JCB bucket.
If I was to strip the Vixen chassis at some point my preference would be HDG but only if I could be sure I could avoid heat distortion.
Moto
At work we run a around 20 Ifor Williams HDG trailers. I can honestly say I've never had any rust appear even when the galvanizing gets worn through from winch cables rubbing, gravel and rubble being dropped in and tipped out day after day or getting dinged by a JCB bucket.
If I was to strip the Vixen chassis at some point my preference would be HDG but only if I could be sure I could avoid heat distortion.
Moto
Heating and Cooling Rates
Steel that is being galvanized is exposed to a wide temperature range from ambient to 850 F. Because parts are immersed at an angle, uneven heating and cooling occur. This exposure to temperature variations allows the steel’s internal stresses to be relieved at different times. Some fabricated assemblies may distort at galvanizing temperature as a result of relieving stresses induced during steel production and in subsequent fabricating operations. For example, a channel frame with a plate should be galvanized separately and bolted later rather than welded together before galvanizing, or it can be welded after galvanizing. Guidelines for minimizing distortion and warpage are provided in ASTM A384, Safeguarding Against Warpage and Distortion During Hot-Dip Galvanizing of Steel Assemblies, and CSA SpecificationG164, Hot Dip Galvanizing of Irregularly Shaped Articles.
Not my words but interesting. Kind of suggests that with something as big as a chassis would distort, how much is another discussion. Those who say they have had their chassis done, did you extensively survey before and after?
Steel that is being galvanized is exposed to a wide temperature range from ambient to 850 F. Because parts are immersed at an angle, uneven heating and cooling occur. This exposure to temperature variations allows the steel’s internal stresses to be relieved at different times. Some fabricated assemblies may distort at galvanizing temperature as a result of relieving stresses induced during steel production and in subsequent fabricating operations. For example, a channel frame with a plate should be galvanized separately and bolted later rather than welded together before galvanizing, or it can be welded after galvanizing. Guidelines for minimizing distortion and warpage are provided in ASTM A384, Safeguarding Against Warpage and Distortion During Hot-Dip Galvanizing of Steel Assemblies, and CSA SpecificationG164, Hot Dip Galvanizing of Irregularly Shaped Articles.
Not my words but interesting. Kind of suggests that with something as big as a chassis would distort, how much is another discussion. Those who say they have had their chassis done, did you extensively survey before and after?
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