I have decided to embark on the removal of the two part paint system(Awlgrip) on my Swordsman's 33' hull this year as she is up for the winter and paint is bubbling in more places than I care to patch up now that she has been up and drying out for the last 6 weeks. Bubbles have appeared on and below the fashion piece below the 'bumper' rail and cove line and transom. As she dries out more and more bubbles appear. I have been advised to use a random orbital sander for the 'flat' areas and a heatgun on all the details to remove the paint back to wood.
Has anyone done this before and are there any particular pitfalls to watch out for (apart from safety gear, progressing slowly and carefully!)(All her varnish will also be stripped back to wood). A suggestion for a professional quality 'random orbital sander' would also be appreciated where the paint removal and dust extraction are both very important.
(I intend to have her hull repainted using a traditional Epifanes single pack paint system).
Thanking you for your kind consideration.
Per/Tireur
Removal of Awlgrip(two part) paint
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PerHansson
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david timothy mark rhodes
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Hi Per
Well I am not sure if what I am about to say is rubbish or not, one very knowledgeable member once told me to be careful not to get the hull too hot with the air gun as it can affect the glue, I rather exoect there are other members that will be able to assist on this.
As for the sander its always a compromise, too big a feller and your arms drop off, too small and it takes forever and you must be very careful about the edge of the sander digging in, for my money especially if I had a helper I would be tempted to hire one and have a weekend blitz if you can thereafter you can have hours of fun with filler and a long board, on the subject of filler the epoxy ones seem best, I have used Hempel, sands like a dream when its just gone off but dont wait for days as it then seems to set like concrete.
Have fun
Well I am not sure if what I am about to say is rubbish or not, one very knowledgeable member once told me to be careful not to get the hull too hot with the air gun as it can affect the glue, I rather exoect there are other members that will be able to assist on this.
As for the sander its always a compromise, too big a feller and your arms drop off, too small and it takes forever and you must be very careful about the edge of the sander digging in, for my money especially if I had a helper I would be tempted to hire one and have a weekend blitz if you can thereafter you can have hours of fun with filler and a long board, on the subject of filler the epoxy ones seem best, I have used Hempel, sands like a dream when its just gone off but dont wait for days as it then seems to set like concrete.
Have fun
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david timothy mark rhodes
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Tim Russell
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I too have heard the advice somewhere about not getting the glue too hot. I think the advice was in the context of using a blowlamp, but hot air guns can get things pretty hot. And I have experience of some glue breaking down in the topsides of Loyal Huntress- whether it was a result of a blowlamp or not I don't know, but I do know that a blowlamp was used to burn off paint at some stage. Personally I would steer clear of using any heat to remove paint, and resort to chemical paint stripper if you have to.
As regards power tools, I have reached the stage where I no longer trust the average DIY tool not to let me down in the middle of some task - it's happened too often - and I have adopted a practice of only buying professional grade tools. Personally I use Bosch Professional (they are blue rather than green) but I am sure there are other options just as good. They cost about 2 to 3 times as much, weigh a fraction more, feel much more solid and smoother running, and I wouldn't go back to buying the cheaper versions ever again.
As regards power tools, I have reached the stage where I no longer trust the average DIY tool not to let me down in the middle of some task - it's happened too often - and I have adopted a practice of only buying professional grade tools. Personally I use Bosch Professional (they are blue rather than green) but I am sure there are other options just as good. They cost about 2 to 3 times as much, weigh a fraction more, feel much more solid and smoother running, and I wouldn't go back to buying the cheaper versions ever again.
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Folly Reach
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Hi Per.
Think Tim is right on this with regards to power tools. I did though burn off the paint on both Svardfisk and Venatrix. Suggest though when paint is stripped and she is completely dry to seal the wood with Eposeal.
This stuff is brilliant, it is by SP and is a two pack epoxy but is solvent based and as thin as water, you can almost hear the wood sucking it in.
Mark Rhodes put me on to it, you mix it 50/50 and it does not go off rapidly in the pot like normal epoxy, it really improves the surface and outer structure of the wood, I then applied an SP hi build primer which is very easy to sand and will support non two pack paints for subsequent coats.
Give me a call if you want any further advice.
Regards
Ian
Think Tim is right on this with regards to power tools. I did though burn off the paint on both Svardfisk and Venatrix. Suggest though when paint is stripped and she is completely dry to seal the wood with Eposeal.
This stuff is brilliant, it is by SP and is a two pack epoxy but is solvent based and as thin as water, you can almost hear the wood sucking it in.
Mark Rhodes put me on to it, you mix it 50/50 and it does not go off rapidly in the pot like normal epoxy, it really improves the surface and outer structure of the wood, I then applied an SP hi build primer which is very easy to sand and will support non two pack paints for subsequent coats.
Give me a call if you want any further advice.
Regards
Ian
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PerHansson
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Thank you Mark, Tim and Ian for all your advice,
I was a bit alarmed to hear that the heat generated from a heatgun could upset the hot-moulded Agba veneer! Alarmed enough to call Bill Dunlop on his mobile (and he answered!...and was of course willing to part with his advice). To summarise, (not sure if he follows the forum but if you do, Bill, please correct me, if I mis-quote you), "a heat gun is OK to use if the surface is not heated up excessively, enough to carefully scrape the paint off".
Unfortunately, the chemical paint strippers don't seem to affect Awlgrip much, if at all, so this method is probably best used for the undercoats and cleaning remnant paint and varnish from hollows and finer details or where a heatgun could do too much damage.
It is a mystery why the paint has lifted in certain areas only, along the 'fashion piece' (softwood) and cove line. There are some visual cracks in the paint in the bow line but not where the bubbling of the paint has occured, aft quarters! Of course, there may be invisible hairline cracks all along the joint to the rubbing strake and cove line where water could have ingressed to blow the paint as a result!?
Frustrating, but perhaps this is the inevitable result of a hard two part paint finish after many years!? Hence my uncertain decision to strip her back to wood and to apply a 'breathable' and more flexible one-coat paint finish. This decision was also encouraged when employing a local 'wood paint surveyor' called Justin Mann(However, uncertain of his experience of hot-molded Agba veneers).
(Ian, I would like to tap your brain further on the SP system if I may. I need to do some research first on the internet before contacting you as I am hesitant to use any two pack system to seal wood!)
Again, many thanks to you all for your advice on this.
Per/Tireur
(P.s. Have decided to try the 'Metabo Professional Random Orbital Sander, ...450 Turbo etc, 2 and 6mm oscillation, variable speed, German engineering etc. Could also be used for polishing sterngear etc as no amount of spray on anti-foul has made a jot of difference!. It should work a treat on the decking too once the new compound is down.
I was a bit alarmed to hear that the heat generated from a heatgun could upset the hot-moulded Agba veneer! Alarmed enough to call Bill Dunlop on his mobile (and he answered!...and was of course willing to part with his advice). To summarise, (not sure if he follows the forum but if you do, Bill, please correct me, if I mis-quote you), "a heat gun is OK to use if the surface is not heated up excessively, enough to carefully scrape the paint off".
Unfortunately, the chemical paint strippers don't seem to affect Awlgrip much, if at all, so this method is probably best used for the undercoats and cleaning remnant paint and varnish from hollows and finer details or where a heatgun could do too much damage.
It is a mystery why the paint has lifted in certain areas only, along the 'fashion piece' (softwood) and cove line. There are some visual cracks in the paint in the bow line but not where the bubbling of the paint has occured, aft quarters! Of course, there may be invisible hairline cracks all along the joint to the rubbing strake and cove line where water could have ingressed to blow the paint as a result!?
Frustrating, but perhaps this is the inevitable result of a hard two part paint finish after many years!? Hence my uncertain decision to strip her back to wood and to apply a 'breathable' and more flexible one-coat paint finish. This decision was also encouraged when employing a local 'wood paint surveyor' called Justin Mann(However, uncertain of his experience of hot-molded Agba veneers).
(Ian, I would like to tap your brain further on the SP system if I may. I need to do some research first on the internet before contacting you as I am hesitant to use any two pack system to seal wood!)
Again, many thanks to you all for your advice on this.
Per/Tireur
(P.s. Have decided to try the 'Metabo Professional Random Orbital Sander, ...450 Turbo etc, 2 and 6mm oscillation, variable speed, German engineering etc. Could also be used for polishing sterngear etc as no amount of spray on anti-foul has made a jot of difference!. It should work a treat on the decking too once the new compound is down.
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Ben
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Per
You've had some good advice, I have always avoided using heat on the hull.
My bosch PEX125 has had many years of abuse and been used for all painting on Playtime for 9 years and its going strong hope I have not tempted fate there).
You find the Bahco Sandvik scrapers very good, I have 2, the 50mm one and the 25mm triangular one. On the 50mm its worth striking the corners off with a grinder into a small radius.
Ben
You've had some good advice, I have always avoided using heat on the hull.
My bosch PEX125 has had many years of abuse and been used for all painting on Playtime for 9 years and its going strong hope I have not tempted fate there).
You find the Bahco Sandvik scrapers very good, I have 2, the 50mm one and the 25mm triangular one. On the 50mm its worth striking the corners off with a grinder into a small radius.
Ben
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PerHansson
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PerHansson
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Scott Pett
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Personally, I think you'll need to "crack" the paint with a heat-gun and then scrape.
A decent gun will have two fan settings and the ability to change the heat levels. My old Bosch has been going for years.
Start with the lowest heat rating and work up gently until you can hear the paint crackling.
Keep the gun moving at all times and work in behind the warmed up bit with the scraper. If you get the warm paint off quickly, the heat will not transfer to the wood.
Best not to smoke at the same time...
Cheers,
Scott
PS: there is an option to fit mattress wallpaper to this Forum.
A decent gun will have two fan settings and the ability to change the heat levels. My old Bosch has been going for years.
Start with the lowest heat rating and work up gently until you can hear the paint crackling.
Keep the gun moving at all times and work in behind the warmed up bit with the scraper. If you get the warm paint off quickly, the heat will not transfer to the wood.
Best not to smoke at the same time...
Cheers,
Scott
PS: there is an option to fit mattress wallpaper to this Forum.
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Scott Pett
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Scott Pett
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Oliver
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Having been painting recently over heavily sanded cured two pack paint with International Perfection my experience was that number 9 thinners won't do anything other than degrease the paint that's there.
If the paint is bubbling in limited places only could you just scrape off what's lifted and give the rest a good sand? This of course relies on no new bubbles forming after you've repainted...
If the paint is bubbling in limited places only could you just scrape off what's lifted and give the rest a good sand? This of course relies on no new bubbles forming after you've repainted...