Griffith body lift the return - POR15 11 years on
Discussion
Back in 2009 I did a mini body lift to check the outriggersand at the time they were in very good condition, I stripped off the powder coat and repainted with POR15.
This is the thread from back then
https://www.pistonheads.com/gassing/topic.asp?h=0&...
There was a comment at the last service that the paint on the outriggers was starting to show signs of rust.
So the last few weekends have been spent stripping the car to do another mini lift to check them. Finished seperating the body and chassis today and they are still looking pretty good. After an initial going over with a wire brush there are a few patchs where some of the old powder coat that was still solid last time has started to flake off but no holes and the mounting points are all sound. Offside is slightly worse than the nearside. Next few weekends will be spent doing some more cleaning up and repainting with POR15 again then she should be good for another few years. Have to say I have been very happy with the performance of the POR15 paint. The Griff is driven year round and there's not other protection on the chassis.
This is the thread from back then
https://www.pistonheads.com/gassing/topic.asp?h=0&...
There was a comment at the last service that the paint on the outriggers was starting to show signs of rust.
So the last few weekends have been spent stripping the car to do another mini lift to check them. Finished seperating the body and chassis today and they are still looking pretty good. After an initial going over with a wire brush there are a few patchs where some of the old powder coat that was still solid last time has started to flake off but no holes and the mounting points are all sound. Offside is slightly worse than the nearside. Next few weekends will be spent doing some more cleaning up and repainting with POR15 again then she should be good for another few years. Have to say I have been very happy with the performance of the POR15 paint. The Griff is driven year round and there's not other protection on the chassis.
Mr.Grooler said:
If that’s 11 years of all-weather use that looks excellent, especially as the metal wasn’t brand new when you painted it last time. Good stuff
Yes I am very happy with the way it's performed. Most of the rusty bits are where I didn't strip off the old powder coat because it was solid then. Really impressed how the POR15 has withstood the stones that get trapped between the body and rails. A lot of small bits of road surfacing fell out when I lifted it up.I'd be disappointed in that result, POR15 should last longer than 10 years if applied correctly and to a correctly prepared surface.
I tested it for Frost in 1994 when we were restoring a Mk2 Zephyr convertible for Practical Classics and Car Restorer magazine, Frost were sponsoring the restoration project so we were sent a selection of their products to test, the photos of me using their stuff would feature in the monthly restoration updates.
POR15 was very new back then so no one really knew haw to apply it including Frost, there was no 'Metal Ready' acid etch available back then either, I soon discovered surface preparation was key and that it worked best on naturally rough surfaces such as cast iron or very heavily pitted steel, if the painted surface was too smooth it wouldn't last very long at all.
We concluded it was an amazing paint but it's very fussy about what surface you're using it on and prep which is the key to all paint work was even more important in some respects with POR15, its also a pain for a number of other reasons, the stuff would go rock hard in the tin after we'd only used it once and we soon moved to considering brushes a single use item.
POR15 does not cling to other paint or powder coat at all, if the OP didn't get rid of every last inch of his powder coat and over painted sections of bare steel but where there were also some powder coat left behind the whole lot will peel off, even on the bare steel sections. Quite honestly it became too much of a pain to use, its fussiness for prep, the type of surfaces it was happy with, the cost and it's short pot life all meant at the end of the day the negatives far outweighed the positives.
We moved back to the two pack paints we'd used to good effect for years, more recently and by that I mean in the last 20 years these two component paints have got even better, and if you're painting something like an outrigger that's going to be subject to impact damage and high speed dirt laden road spray thrown up by the front tyres which is effectively aquablasting you're way better off with a high solids industrial marine grade 2k epoxy mastic.
Prep is still key but epoxy mastic is way way less fussy in this respect than POR15, especially when applied over other coatings and smoother steel surfaces, used correctly on a properly prepped surface epoxy mastic simply has no equal. The best epoxy mastic paints are made by Jotun, their latest Jotamastic formula being number 90, and the best in the Jotamastic range is '90 Aluminum' as it adds galvanic protection.
Jotamastic 90 Aluminum is whats being applied to my chassis right now and we fully expect it to last 30 years or more.
https://www.pistonheads.com/gassing/topic.asp?h=0&...
https://www.pistonheads.com/gassing/topic.asp?h=0&...
I tested it for Frost in 1994 when we were restoring a Mk2 Zephyr convertible for Practical Classics and Car Restorer magazine, Frost were sponsoring the restoration project so we were sent a selection of their products to test, the photos of me using their stuff would feature in the monthly restoration updates.
POR15 was very new back then so no one really knew haw to apply it including Frost, there was no 'Metal Ready' acid etch available back then either, I soon discovered surface preparation was key and that it worked best on naturally rough surfaces such as cast iron or very heavily pitted steel, if the painted surface was too smooth it wouldn't last very long at all.
We concluded it was an amazing paint but it's very fussy about what surface you're using it on and prep which is the key to all paint work was even more important in some respects with POR15, its also a pain for a number of other reasons, the stuff would go rock hard in the tin after we'd only used it once and we soon moved to considering brushes a single use item.
POR15 does not cling to other paint or powder coat at all, if the OP didn't get rid of every last inch of his powder coat and over painted sections of bare steel but where there were also some powder coat left behind the whole lot will peel off, even on the bare steel sections. Quite honestly it became too much of a pain to use, its fussiness for prep, the type of surfaces it was happy with, the cost and it's short pot life all meant at the end of the day the negatives far outweighed the positives.
We moved back to the two pack paints we'd used to good effect for years, more recently and by that I mean in the last 20 years these two component paints have got even better, and if you're painting something like an outrigger that's going to be subject to impact damage and high speed dirt laden road spray thrown up by the front tyres which is effectively aquablasting you're way better off with a high solids industrial marine grade 2k epoxy mastic.
Prep is still key but epoxy mastic is way way less fussy in this respect than POR15, especially when applied over other coatings and smoother steel surfaces, used correctly on a properly prepped surface epoxy mastic simply has no equal. The best epoxy mastic paints are made by Jotun, their latest Jotamastic formula being number 90, and the best in the Jotamastic range is '90 Aluminum' as it adds galvanic protection.
Jotamastic 90 Aluminum is whats being applied to my chassis right now and we fully expect it to last 30 years or more.
https://www.pistonheads.com/gassing/topic.asp?h=0&...
https://www.pistonheads.com/gassing/topic.asp?h=0&...
Colin,
What year is your Griffith?
Your chassis looks to be in excellent nick. Not many left now with original outriggers!
My 1996 500 appears to still have very sound outriggers but I have kept it clear of debris for the past 16 years. And have treated it with rust killer and Dinitrol over the years.
What year is your Griffith?
Your chassis looks to be in excellent nick. Not many left now with original outriggers!
My 1996 500 appears to still have very sound outriggers but I have kept it clear of debris for the past 16 years. And have treated it with rust killer and Dinitrol over the years.
When I bought my current Griff in 2008, I went though a similar process of cleaning back any rusty areas then two coats of POR15 on bare areas followed by a coat of Smoothrite (white and black mixed to give a very close match to the original chassis colour) applied while the POR15 was still tacky (POR15 advice). Since then I have cleaned and checked the chassis every few years, but it is still in excellent condition. No outrigger replacement needed for many years to come according to those that work on TVR's everyday. 
If the OP is happy with the result thats all that matters, however if it was my car I'd be disappointed as the POR15 has clearly failed as demonstrated by the significant presence of rust. The inspection may be 10 years after application of the POR15 but it hasn't lasted 10 years, that corrosion didn't just appear in the last few months, its been there for years meaning the POR15 started to fail very early on after it was applied. I'd definitely encourage the OP to switch to an industrial marine grade two component epoxy mastic system, this is what the professionals use when painting oil rigs and ship hulls where no BS long term results in hostile salt heavy industrial working environments are called for.
Single part moisture cured polyurethane paints (MCPU) have their place but no one in the marine painting industry is using MCPUs on structures or surfaces that are expected to suffer high traffic and or will be subjected to abrasive attack conditions, in these situations a professional industrial painter will always select a two part epoxy mastic system. POR15 isn't some magic paint unknown to professional painters it's just an MCPU but in it's POR15 form should be considered a hobby paint for home use intended to be applied by amateurs, a professional experienced industrial painter would have nothing to do with it. I'm afraid to say POR15 is more about good marketing than it is about a truly long lasting and durable finish essential in a tough working industrial environment.
I tested POR15 for Frost in the early 90's before they even put it in their catalogue and while I did occasionally achieve good results it was all very inconsistent, it only performed acceptably when all the stars and the moon were aligned at the same time, by that I mean the prep and the surface of the substrate had to be just so, and this is almost impossible to achieve over every millimeter of the painted surface. The unique chemistry of moisture-cured urethanes does have its limitations, if there is too much moisture on the surface of the substrate or in the atmosphere the curing process will occur so quickly that carbon dioxide given off can become trapped, resulting in pinholes or voids in the coating film. Conversely, in cold temperatures, below 15°F, moisture levels in the air drop significantly, so the reaction rate of moisture-cured urethanes is slowed to a level where a good bond to the substrate will never be achieved.
But lets assume you are lucky enough to get a good bond to the substrate this is not the end of the problems with POR15, because when it cures its a very hard finish indeed. On the face of it this may sound fantastic but it's actually the opposite of what you want, much like powder coat we found POR15 would chip, once chipped water would get under it and it would start to lift and peel. What you actually need in a paint that's going to do service in harsh environments is a better, stronger, less fussy substrate bond and flexibility. A tough well bonded flexible finish will last way longer than a hard brittle one and this is exactly why epoxy mastic paints exist, the already vastly superior performance of a two component epoxy paint is further enhanced by adding a plastisiser, this plastisiser (the mastic element) creates a permanently flexible finish that massively enhances the ability of the paint to resist impact damage and to some degree is also self healing too.
Outriggers on a TVR are bombarded with stones and dirt laden spray thrown up by the tyres, what you've got is a crude but rather effective media blasting system that peppers the outriggers with fine sharp debris. If you've ever used the type of pressure washer that also takes a sand media you'll know just how effectively it can remove stubbon stains on a patio, and it'll soon lift paint off a metal gate too. I'd definitively recommend moving on from POR15 and switching to a proper industrial marine grade epoxy mastic paint system, the results will be night and day better, I'd also recommend stopping the problem at source with a set of Peter Esslings excellent laser cut stainless steel outrigger protectors. Outrigger protectors will stop road debris from peppering the outrigger tubes and stop mud and damp leaf mulch from collecting in the outrigger corners, this muck sits on the platforms the corner strengthening fillets create which soon rots out the corners, the upper hidden corners are the first point of failure and you simply can't see it with the body on.
Jotamastic 90 is the way forward and if you select the Aluminium version you get the added benefit of galvanic protection from this amazingly tough yet flexible two component epoxy mastic system, finish off with outrigger protectors and your outriggers will last 20 to 30 years not the 10 years or less the POR15 gave the OP before repainting was required. Here's my chassis painted in Jotamastic 90 Aluminium, I'm expecting it to last 30 years before we need to lift the body again, and as it turns out this super tough yet flexible industrial marine grade epoxy paint is also an extremely close colour match to the original silver/grey finish applied by TVR up to the end of 1996.
The only problem for the home restorer in selecting an industrial epoxy mastic is the larger quantities this paint is typically sold in, because it's intended to be used by professionals over large surface areas the minimum quantity you can buy it in is five litres which is a lot of paint, its actually about twice what you need to paint a TVR chassis if you're also painting the wishbones, hubs, anti roll bars ect too.
If buying a bit more than you need isnt a problem for you I recommend talking with SML Marine Paints, this is where I purchased my 5 litres of Jotamastic 90 Aluminum and the service and advice was excellent.
https://www.smlmarinepaints.co.uk/primers/jotamast...
If however five litres is too much paint for you, and it probably will be, that's where Rustbuster can help. The EM121 epoxy mastic they sell is the same a Jotun's Smart Pack 1:1 mix ratio epoxy mastic product it's just Rusbuster offer it in far smaller quantities so way more practical for the home restorer, the enthusiastic amateur does however pay for this convenience as per litre the Rustbuster EM121 is twice the price of the Jotun Smart Pack. The owner of Rustbuster has created a nice business model where he's basically doubling his dough for a little bit of work filling tins and posting it out, and I say well done him as it's clearly working well and gives people the smaller quantities of these paints people want.... all be it at a premium price point.
https://www.rust.co.uk/product/cat/em-121-epoxy-ru...
Single part moisture cured polyurethane paints (MCPU) have their place but no one in the marine painting industry is using MCPUs on structures or surfaces that are expected to suffer high traffic and or will be subjected to abrasive attack conditions, in these situations a professional industrial painter will always select a two part epoxy mastic system. POR15 isn't some magic paint unknown to professional painters it's just an MCPU but in it's POR15 form should be considered a hobby paint for home use intended to be applied by amateurs, a professional experienced industrial painter would have nothing to do with it. I'm afraid to say POR15 is more about good marketing than it is about a truly long lasting and durable finish essential in a tough working industrial environment.
I tested POR15 for Frost in the early 90's before they even put it in their catalogue and while I did occasionally achieve good results it was all very inconsistent, it only performed acceptably when all the stars and the moon were aligned at the same time, by that I mean the prep and the surface of the substrate had to be just so, and this is almost impossible to achieve over every millimeter of the painted surface. The unique chemistry of moisture-cured urethanes does have its limitations, if there is too much moisture on the surface of the substrate or in the atmosphere the curing process will occur so quickly that carbon dioxide given off can become trapped, resulting in pinholes or voids in the coating film. Conversely, in cold temperatures, below 15°F, moisture levels in the air drop significantly, so the reaction rate of moisture-cured urethanes is slowed to a level where a good bond to the substrate will never be achieved.
But lets assume you are lucky enough to get a good bond to the substrate this is not the end of the problems with POR15, because when it cures its a very hard finish indeed. On the face of it this may sound fantastic but it's actually the opposite of what you want, much like powder coat we found POR15 would chip, once chipped water would get under it and it would start to lift and peel. What you actually need in a paint that's going to do service in harsh environments is a better, stronger, less fussy substrate bond and flexibility. A tough well bonded flexible finish will last way longer than a hard brittle one and this is exactly why epoxy mastic paints exist, the already vastly superior performance of a two component epoxy paint is further enhanced by adding a plastisiser, this plastisiser (the mastic element) creates a permanently flexible finish that massively enhances the ability of the paint to resist impact damage and to some degree is also self healing too.
Outriggers on a TVR are bombarded with stones and dirt laden spray thrown up by the tyres, what you've got is a crude but rather effective media blasting system that peppers the outriggers with fine sharp debris. If you've ever used the type of pressure washer that also takes a sand media you'll know just how effectively it can remove stubbon stains on a patio, and it'll soon lift paint off a metal gate too. I'd definitively recommend moving on from POR15 and switching to a proper industrial marine grade epoxy mastic paint system, the results will be night and day better, I'd also recommend stopping the problem at source with a set of Peter Esslings excellent laser cut stainless steel outrigger protectors. Outrigger protectors will stop road debris from peppering the outrigger tubes and stop mud and damp leaf mulch from collecting in the outrigger corners, this muck sits on the platforms the corner strengthening fillets create which soon rots out the corners, the upper hidden corners are the first point of failure and you simply can't see it with the body on.
Jotamastic 90 is the way forward and if you select the Aluminium version you get the added benefit of galvanic protection from this amazingly tough yet flexible two component epoxy mastic system, finish off with outrigger protectors and your outriggers will last 20 to 30 years not the 10 years or less the POR15 gave the OP before repainting was required. Here's my chassis painted in Jotamastic 90 Aluminium, I'm expecting it to last 30 years before we need to lift the body again, and as it turns out this super tough yet flexible industrial marine grade epoxy paint is also an extremely close colour match to the original silver/grey finish applied by TVR up to the end of 1996.
The only problem for the home restorer in selecting an industrial epoxy mastic is the larger quantities this paint is typically sold in, because it's intended to be used by professionals over large surface areas the minimum quantity you can buy it in is five litres which is a lot of paint, its actually about twice what you need to paint a TVR chassis if you're also painting the wishbones, hubs, anti roll bars ect too.
If buying a bit more than you need isnt a problem for you I recommend talking with SML Marine Paints, this is where I purchased my 5 litres of Jotamastic 90 Aluminum and the service and advice was excellent.
https://www.smlmarinepaints.co.uk/primers/jotamast...
If however five litres is too much paint for you, and it probably will be, that's where Rustbuster can help. The EM121 epoxy mastic they sell is the same a Jotun's Smart Pack 1:1 mix ratio epoxy mastic product it's just Rusbuster offer it in far smaller quantities so way more practical for the home restorer, the enthusiastic amateur does however pay for this convenience as per litre the Rustbuster EM121 is twice the price of the Jotun Smart Pack. The owner of Rustbuster has created a nice business model where he's basically doubling his dough for a little bit of work filling tins and posting it out, and I say well done him as it's clearly working well and gives people the smaller quantities of these paints people want.... all be it at a premium price point.
https://www.rust.co.uk/product/cat/em-121-epoxy-ru...
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