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Robert Reed
Joined: 22 Oct 2009
Posts: 331
Location: Dallas/Ft.Worth
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 Posted: Fri Aug 10, 2012 2:51 pm Post subject: Sanding, sanding, some more sanding and so on. |
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The summer after I turned 11 years old my step father informed me that I was old enough to start working at the Garage and Body Shop that he and his brothers owned. My joyful unpaid job from then on every weekend and through the summers until I turned 14, got my drivers licence and a paying job was to do the wet sanding of the cars in the shop for body repair and painting. (Yes, 14 was when we could get drivers licences back in those old days.) Sanding back then used wet sandpaper, a bucket and a sanding block similar to what we have today. We did have something called a JitterBug air powered sander for the very rough sanding but most sanding used just your hand, water, and paper. The sanding block wasn't really that useful on anything other than flat surfaces.
What used to really irritate me was after a long session of sanding a fender, door, or hood I would proudly proclaim that it was done. My stepfather would come out to the sanding and washing bay and walk over to the car, rub his hands over the surface and quickly tell me that I had a lot yet to do and get back to it. He would then point out every area that I had missed or not done correctly. I couldn't for the life of me understand how he knew it wasn't done just by rubbing his hands over it. Now before I go further, I must state that his hands were about the roughest, cracked, banged up, and greese imbedded you would ever see. You didn't want to shake hands with him because it reminded you of holding a big pine cone. Yet, he could feel any flaws in that surface instantly. It used to infuriate me to no end and I would say a few choice words and go back to sanding only to repeat the process two or three times before finally getting a grunt followed by him picking up some sandpaper and working on a couple of areas before proclaiming it ready.
Fast forward to now and finally after all of these years I totally understand. The HANDS are an incredibily sensitive tool for determining when a surface is fully sanded and for picking out the slightest flaw in a surface as large as a wing. Flaws that you can't see, a microscopic speck of dust, or a low spot can be instantly detected by just rubbing a clean dry hand over the surface.
I have just finished preparing the second wing for painting. I put on the first two coats of primer and have sanded them down preparing for two more coats that will get another sanding before the color coats. What I found in the process was what my step-father had been doing all those years back. He would clean the surface and wait for it to dry. He would then clean his hands and dry them before sliding it across the surface. I have used the same technique before painting to clear any dust from the surface and to know when I had all of it cleared. During the sanding process, I will sand until I think it is about there, clean the surface to remove all sanding dust, then use the dry hand rub to detect any flaws. A quick mark with a pencil over any flaws is followed by another sanding session and repeat the same thing again. A couple of iterations and you will find the surface is ready for the next painting process.
I also use the same process just before putting on the paint. I wash the heck out of my hands to remove any oil and dry them. I then wet a rag with rubbing alcahol and use it to clean my hand. Using my hand I rub it over the surface to pickup any dust and wipe it on the damp rag. I repeat this process until I can no longer feel any dust anywhere on the surface. This will always take at least two passes. If I feel anything on a pass, I wipe my hand after making the pass and do it again. I know they recommend tack cloth but have found tack cloths can leave residue and you really don't know if it get everything. I hate to admit but my step-father actually know what he was doing, at least when it came to sanding.
NOW if he had just taught me how to spray paint! Anyway, the primer is going on great and the color coat is a futur challenge.
Making slow progress,
Bob Reed
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galinhdz(at)gmail.com
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| Posted: Fri Aug 10, 2012 2:59 pm Post subject: Sanding, sanding, some more sanding and so on. |
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NICE! Remember, slow progress is how the turtle beat the hare.  )
On Fri, Aug 10, 2012 at 5:50 PM, Robert Reed <robertr237(at)att.net (robertr237(at)att.net)> wrote:
[quote]
The summer after I turned 11 years old my step father informed me that I was old enough to start working at the Garage and Body Shop that he and his brothers owned. My joyful unpaid job from then on every weekend and through the summers until I turned 14, got my drivers licence and a paying job was to do the wet sanding of the cars in the shop for body repair and painting. (Yes, 14 was when we could get drivers licences back in those old days.) Sanding back then used wet sandpaper, a bucket and a sanding block similar to what we have today. We did have something called a JitterBug air powered sander for the very rough sanding but most sanding used just your hand, water, and paper. The sanding block wasn't really that useful on anything other than flat surfaces.
What used to really irritate me was after a long session of sanding a fender, door, or hood I would proudly proclaim that it was done. My stepfather would come out to the sanding and washing bay and walk over to the car, rub his hands over the surface and quickly tell me that I had a lot yet to do and get back to it. He would then point out every area that I had missed or not done correctly. I couldn't for the life of me understand how he knew it wasn't done just by rubbing his hands over it. Now before I go further, I must state that his hands were about the roughest, cracked, banged up, and greese imbedded you would ever see. You didn't want to shake hands with him because it reminded you of holding a big pine cone. Yet, he could feel any flaws in that surface instantly. It used to infuriate me to no end and I would say a few choice words and go back to sanding only to repeat the process two or three times before finally getting a grunt followed by him picking up some sandpaper and working on a couple of areas before proclaiming it ready.
Fast forward to now and finally after all of these years I totally understand. The HANDS are an incredibily sensitive tool for determining when a surface is fully sanded and for picking out the slightest flaw in a surface as large as a wing. Flaws that you can't see, a microscopic speck of dust, or a low spot can be instantly detected by just rubbing a clean dry hand over the surface.
I have just finished preparing the second wing for painting. I put on the first two coats of primer and have sanded them down preparing for two more coats that will get another sanding before the color coats. What I found in the process was what my step-father had been doing all those years back. He would clean the surface and wait for it to dry. He would then clean his hands and dry them before sliding it across the surface. I have used the same technique before painting to clear any dust from the surface and to know when I had all of it cleared. During the sanding process, I will sand until I think it is about there, clean the surface to remove all sanding dust, then use the dry hand rub to detect any flaws. A quick mark with a pencil over any flaws is followed by another sanding session and repeat the same thing again. A couple of iterations and you will find the surface is ready for the next painting process.
I also use the same process just before putting on the paint. I wash the heck out of my hands to remove any oil and dry them. I then wet a rag with rubbing alcahol and use it to clean my hand. Using my hand I rub it over the surface to pickup any dust and wipe it on the damp rag. I repeat this process until I can no longer feel any dust anywhere on the surface. This will always take at least two passes. If I feel anything on a pass, I wipe my hand after making the pass and do it again. I know they recommend tack cloth but have found tack cloths can leave residue and you really don't know if it get everything. I hate to admit but my step-father actually know what he was doing, at least when it came to sanding.
NOW if he had just taught me how to spray paint! Anyway, the primer is going on great and the color coat is a futur challenge.
Making slow progress,
Bob Reed
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sstearns2(at)yahoo.com
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| Posted: Fri Aug 10, 2012 3:23 pm Post subject: Sanding, sanding, some more sanding and so on. |
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Misting on a guide coat of cheap spray paint before you start sanding is pretty effective too. The cheap stuff comes right off with acetone.
Scott
On Aug 10, 2012, at 3:50 PM, Robert Reed <robertr237(at)att.net (robertr237(at)att.net)> wrote:
[quote]
The summer after I turned 11 years old my step father informed me that I was old enough to start working at the Garage and Body Shop that he and his brothers owned. My joyful unpaid job from then on every weekend and through the summers until I turned 14, got my drivers licence and a paying job was to do the wet sanding of the cars in the shop for body repair and painting. (Yes, 14 was when we could get drivers licences back in those old days.) Sanding back then used wet sandpaper, a bucket and a sanding block similar to what we have today. We did have something called a JitterBug air powered sander for the very rough sanding but most sanding used just your hand, water, and paper. The sanding block wasn't really that useful on anything other than flat surfaces.
What used to really irritate me was after a long session of sanding a fender, door, or hood I would proudly proclaim that it was done. My stepfather would come out to the sanding and washing bay and walk over to the car, rub his hands over the surface and quickly tell me that I had a lot yet to do and get back to it. He would then point out every area that I had missed or not done correctly. I couldn't for the life of me understand how he knew it wasn't done just by rubbing his hands over it. Now before I go further, I must state that his hands were about the roughest, cracked, banged up, and greese imbedded you would ever see. You didn't want to shake hands with him because it reminded you of holding a big pine cone. Yet, he could feel any flaws in that surface instantly. It used to infuriate me to no end and I would say a few choice words and go back to sanding only to repeat the process two or three times before finally getting a grunt followed by him picking up some sandpaper and working on a couple of areas before proclaiming it ready.
Fast forward to now and finally after all of these years I totally understand. The HANDS are an incredibily sensitive tool for determining when a surface is fully sanded and for picking out the slightest flaw in a surface as large as a wing. Flaws that you can't see, a microscopic speck of dust, or a low spot can be instantly detected by just rubbing a clean dry hand over the surface.
I have just finished preparing the second wing for painting. I put on the first two coats of primer and have sanded them down preparing for two more coats that will get another sanding before the color coats. What I found in the process was what my step-father had been doing all those years back. He would clean the surface and wait for it to dry. He would then clean his hands and dry them before sliding it across the surface. I have used the same technique before painting to clear any dust from the surface and to know when I had all of it cleared. During the sanding process, I will sand until I think it is about there, clean the surface to remove all sanding dust, then use the dry hand rub to detect any flaws. A quick mark with a pencil over any flaws is followed by another sanding session and repeat the same thing again. A couple of iterations and you will find the surface is ready for the next painting process.
I also use the same process just before putting on the paint. I wash the heck out of my hands to remove any oil and dry them. I then wet a rag with rubbing alcahol and use it to clean my hand. Using my hand I rub it over the surface to pickup any dust and wipe it on the damp rag. I repeat this process until I can no longer feel any dust anywhere on the surface. This will always take at least two passes. If I feel anything on a pass, I wipe my hand after making the pass and do it again. I know they recommend tack cloth but have found tack cloths can leave residue and you really don't know if it get everything. I hate to admit but my step-father actually know what he was doing, at least when it came to sanding.
NOW if he had just taught me how to spray paint! Anyway, the primer is going on great and the color coat is a futur challenge.
Making slow progress,
Bob Reed
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Robert Reed
Joined: 22 Oct 2009
Posts: 331
Location: Dallas/Ft.Worth
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| Posted: Fri Aug 10, 2012 5:29 pm Post subject: Sanding, sanding, some more sanding and so on. |
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I used that process early on to find the low spots and it does work great for that.
Bob
From: Scott Stearns <sstearns2(at)yahoo.com>
To: "kis-list(at)matronics.com" <kis-list(at)matronics.com>
Sent: Fri, August 10, 2012 6:23:08 PM
Subject: Re: Sanding, sanding, some more sanding and so on.
Misting on a guide coat of cheap spray paint before you start sanding is pretty effective too. The cheap stuff comes right off with acetone.
Scott
On Aug 10, 2012, at 3:50 PM, Robert Reed <robertr237(at)att.net (robertr237(at)att.net)> wrote:
[quote]
The summer after I turned 11 years old my step father informed me that I was old enough to start working at the Garage and Body Shop that he and his brothers owned. My joyful unpaid job from then on every weekend and through the summers until I turned 14, got my drivers licence and a paying job was to do the wet sanding of the cars in the shop for body repair and painting. (Yes, 14 was when we could get drivers licences back in those old days.) Sanding back then used wet sandpaper, a bucket and a sanding block similar to what we have today. We did have something called a JitterBug air powered sander for the very rough sanding but most sanding used just your hand, water, and paper. The sanding block wasn't really that useful on anything other than flat surfaces.
What used to really irritate me was after a long session of sanding a fender, door, or hood I would proudly proclaim that it was done. My stepfather would come out to the sanding and washing bay and walk over to the car, rub his hands over the surface and quickly tell me that I had a lot yet to do and get back to it. He would then point out every area that I had missed or not done correctly. I couldn't for the life of me understand how he knew it wasn't done just by rubbing his hands over it. Now before I go further, I must state that his hands were about the roughest, cracked, banged up, and greese imbedded you would ever see. You didn't want to shake hands with him because it reminded you of holding a big pine cone. Yet, he could feel any flaws in that surface instantly. It used to infuriate me to no end and I would say a few choice words and go back to sanding only to repeat the process two or three times before finally getting a grunt followed by him picking up some sandpaper and working on a couple of areas before proclaiming it ready.
Fast forward to now and finally after all of these years I totally understand. The HANDS are an incredibily sensitive tool for determining when a surface is fully sanded and for picking out the slightest flaw in a surface as large as a wing. Flaws that you can't see, a microscopic speck of dust, or a low spot can be instantly detected by just rubbing a clean dry hand over the surface.
I have just finished preparing the second wing for painting. I put on the first two coats of primer and have sanded them down preparing for two more coats that will get another sanding before the color coats. What I found in the process was what my step-father had been doing all those years back. He would clean the surface and wait for it to dry. He would then clean his hands and dry them before sliding it across the surface. I have used the same technique before painting to clear any dust from the surface and to know when I had all of it cleared. During the sanding process, I will sand until I think it is about there, clean the surface to remove all sanding dust, then use the dry hand rub to detect any flaws. A quick mark with a pencil over any flaws is followed by another sanding session and repeat the same thing again. A couple of iterations and you will find the surface is ready for the next painting process.
I also use the same process just before putting on the paint. I wash the heck out of my hands to remove any oil and dry them. I then wet a rag with rubbing alcahol and use it to clean my hand. Using my hand I rub it over the surface to pickup any dust and wipe it on the damp rag. I repeat this process until I can no longer feel any dust anywhere on the surface. This will always take at least two passes. If I feel anything on a pass, I wipe my hand after making the pass and do it again. I know they recommend tack cloth but have found tack cloths can leave residue and you really don't know if it get everything. I hate to admit but my step-father actually know what he was doing, at least when it came to sanding.
NOW if he had just taught me how to spray paint! Anyway, the primer is going on great and the color coat is a futur challenge.
Making slow progress,
Bob Reed
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fredorosa(at)gmail.com
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| Posted: Sat Aug 11, 2012 4:18 am Post subject: Sanding, sanding, some more sanding and so on. |
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What primer are you using and what top coat paint? I've been rolling on UV Smooth Prime (Polyfiber) and like the way it fills and sands. I'm planning on a water base top coat by Polyfiber also.
Al
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Robert Reed
Joined: 22 Oct 2009
Posts: 331
Location: Dallas/Ft.Worth
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| Posted: Sat Aug 11, 2012 7:10 pm Post subject: Sanding, sanding, some more sanding and so on. |
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Al,
I looked at using UV Smooth Prime and the PolyFiber topcoat, the Stewart System, and System Three Marine Paint system. The UV Smooth Prime looked real good for a primer but I found too many negatives on the PolyFiber for composites that I backed off on using it. I also have the issue now of not having any available facilities for spray painting so will be forced to find an alternate way to finish. The Steward system definately didn't recomend anything but HVLP spray.
I picked the System Three system because it fully supported roll and tip or spraying. I am using SilverTip Yacht Primer. It is a waterborne, two-part epoxy coating specifically formulated as a tough, below-the-waterline primer for marine topcoats. I figured if it would work for marine applications it should work well for aircraft use as well. The primer does not contain a UV absorber. It does go on easily with a roller and flows out nicely if you make sure and keep your area within temperature range of 65-80 degrees with HIGH 80% humidity. I have my shop airconditioned and used wet towels, sprayed the floor and put a wet towel over the airconditioner. It raised the humidity level and the primer spread out perfectly. If you don't do this, the primer dries so quickly that it will leave marks from the brush tip.
For the color coats I will be useing System Three WR-LPU Topcoat. It is a two-part linear polyurethane coating specifically formulated for maximum performance and ease of use. Available in 12 standard colors as well as clear satin and high gloss. When cured it is moisture, solvent and fuel resistant. WR-LPU contains UV absorbers and will not yellow or lose gloss for years, depending on exposure. (Portions copied from lit) Both primer and top coat are water based. The topcoat can use a crosslinker to produce a super hard finish. Thinning uses distilled water and the top coat does not require mixing with other than water unless crosslinker is added which is only a few drops per ounce. The top color coat paint appears to be much thinner than the primer and with recommend water addition it should flow out much better than the primer. I will be doing some test parts in the next few weeks to see how it flows out in various conditions.
My plan is to use the roll and tip to apply two coats of primer. Sand the first two coats to make sure of filling any minor low spots. Follow with two additional primer coats that will be sanded for top coat preparation. I will then add three coats of color top coats with crosslinker added again using roll and tip. I will let the color coats fully cure and then perform a color sanding to remove any imperfectioins in the surface. Finally, on those parts that I can get to my shop for finish I will followup with two to three coats of clear high gloss with the crosslinker again added. I don't expect to have to finish sand and buff the clear but will if needed. The fuselage is going to be a bigger problem since it is at the hangar and can't be inclosed and protected for painting. I also will have little control over dust and humidity issues. The plan...wait for a warm high humidity rainy week and spend a few days of misery trying to get the paint on. That will not come before late fall or early next spring. Dallas is just too darn dry.
Finally, I know this is NOT the best way to finish my plane. That is a given but there are no paint facilities on my airport and the airport forbids painting (spray) in the hangars. Can't say I blame them. Probably wouldn't make much difference if they did, the electrical available to my bay won't even start my compressor. So my options are limited as are my funds for paying someone to put on a multi-thousand dollar paint job. It is both labor and time intensive but hopefully it will produce a good finish. It won't win any awards but shouldn't make me hide my head in shame either.
Bob
From: ALFRED ROSA <fredorosa(at)gmail.com>
To: kis-list(at)matronics.com
Sent: Sat, August 11, 2012 7:18:24 AM
Subject: Re: Sanding, sanding, some more sanding and so on.
What primer are you using and what top coat paint? I've been rolling on UV Smooth Prime (Polyfiber) and like the way it fills and sands. I'm planning on a water base top coat by Polyfiber also.
Al
[quote][b]
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sstearns2(at)yahoo.com
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| Posted: Sat Aug 11, 2012 10:31 pm Post subject: Sanding, sanding, some more sanding and so on. |
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I primed and painted my airplane outside. My airport is also 100% no spraying in hangars, but they did not care about outside. I used the UV smooth prime with a roller initally, expensive waste of time. I sprayed auto body high build primer and painted with PPG Delfleet with a $15 harbor freight gun. The finish had a lot of orange peel, but remarkably little dust/dirt. I wetsanded and buffed the paint and it looks great. I would prime/paint outside again for sure. I would not try to paint the whole plane at once, but spilt it up into wing, fuselage, and everything else on different days.
Scott
From: Robert Reed <robertr237(at)att.net>
To: kis-list(at)matronics.com
Sent: Saturday, August 11, 2012 8:09 PM
Subject: Re: Sanding, sanding, some more sanding and so on.
Al,
I looked at using UV Smooth Prime and the PolyFiber topcoat, the Stewart System, and System Three Marine Paint system. The UV Smooth Prime looked real good for a primer but I found too many negatives on the PolyFiber for composites that I backed off on using it. I also have the issue now of not having any available facilities for spray painting so will be forced to find an alternate way to finish. The Steward system definately didn't recomend anything but HVLP spray.
I picked the System Three system because it fully supported roll and tip or spraying. I am using SilverTip Yacht Primer. It is a waterborne, two-part epoxy coating specifically formulated as a tough, below-the-waterline primer for marine topcoats. I figured if it would work for marine applications it should work well for aircraft use as well. The primer does not contain a UV absorber. It does go on easily with a roller and flows out nicely if you make sure and keep your area within temperature range of 65-80 degrees with HIGH 80% humidity. I have my shop airconditioned and used wet towels, sprayed the floor and put a wet towel over the airconditioner. It raised the humidity level and the primer spread out perfectly. If you don't do this, the primer dries so quickly that it will leave marks from the brush tip.
For the color coats I will be useing System Three WR-LPU Topcoat. It is a two-part linear polyurethane coating specifically formulated for maximum performance and ease of use. Available in 12 standard colors as well as clear satin and high gloss. When cured it is moisture, solvent and fuel resistant. WR-LPU contains UV absorbers and will not yellow or lose gloss for years, depending on exposure. (Portions copied from lit) Both primer and top coat are water based. The topcoat can use a crosslinker to produce a super hard finish. Thinning uses distilled water and the top coat does not require mixing with other than water unless crosslinker is added which is only a few drops per ounce. The top color coat paint appears to be much thinner than the primer and with recommend water addition it should flow out much better than the primer. I will be doing some test parts in the next few weeks to see how it flows out in various conditions.
My plan is to use the roll and tip to apply two coats of primer. Sand the first two coats to make sure of filling any minor low spots. Follow with two additional primer coats that will be sanded for top coat preparation. I will then add three coats of color top coats with crosslinker added again using roll and tip. I will let the color coats fully cure and then perform a color sanding to remove any imperfectioins in the surface. Finally, on those parts that I can get to my shop for finish I will followup with two to three coats of clear high gloss with the crosslinker again added. I don't expect to have to finish sand and buff the clear but will if needed. The fuselage is going to be a bigger problem since it is at the hangar and can't be inclosed and protected for painting. I also will have little control over dust and humidity issues. The plan...wait for a warm high humidity rainy week and spend a few days of misery trying to get the paint on. That will not come before late fall or early next spring. Dallas is just too darn dry.
Finally, I know this is NOT the best way to finish my plane. That is a given but there are no paint facilities on my airport and the airport forbids painting (spray) in the hangars. Can't say I blame them. Probably wouldn't make much difference if they did, the electrical available to my bay won't even start my compressor. So my options are limited as are my funds for paying someone to put on a multi-thousand dollar paint job. It is both labor and time intensive but hopefully it will produce a good finish. It won't win any awards but shouldn't make me hide my head in shame either.
Bob
From: ALFRED ROSA <fredorosa(at)gmail.com>
To: kis-list(at)matronics.com
Sent: Sat, August 11, 2012 7:18:24 AM
Subject: Re: Sanding, sanding, some more sanding and so on.
What primer are you using and what top coat paint? I've been rolling on UV Smooth Prime (Polyfiber) and like the way it fills and sands. I'm planning on a water base top coat by Polyfiber also.
Al
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fredorosa(at)gmail.com
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| Posted: Sun Aug 12, 2012 4:04 am Post subject: Sanding, sanding, some more sanding and so on. |
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Bob,
I will be getting this portable garage to erect in my yard for painting the plane.
http://www.portablegaragedepot.com/index.cfm?sku=SZ102810H&catid=66
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bakerocb
Joined: 15 Jan 2006
Posts: 727
Location: FAIRFAX VA
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| Posted: Sun Aug 12, 2012 4:29 am Post subject: Sanding, sanding, some more sanding and so on. |
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8/12/2012
Hello Robert, You wrote:
1) “The primer does not contain a UV absorber.” and “When cured it is moisture, solvent and fuel resistant. WR-LPU contains UV absorbers and will not yellow or lose gloss for years, depending on exposure. “
My understanding of UV protection for the resin used in the fiberglass structure underlying the painted surface of our airplanes is that there are two methods available: blockage and chemical absorption.
The down side of chemical absorption is that exposure to UV causes the chemicals in the chemical absorption method to be consumed or modified over time so that eventually UV protection is no longer provided to the underlying structure. The blockage method provides permanent UV protection as long as the covering containing the blockage material is not cracked or penetrated.
There are three materials commonly used in the blockage method: aluminum powder, carbon black, and mica chips (UV Smooth Prime). I think that the mica chips in UV Smooth Prime provides the best (least messy and lightest) protection.
However I would not depend upon UV Smooth Prime to provide the the long term priming filler needed to prevent eventual showing of the fiberglass fabric weave pattern through the paint surface. I would apply one or two coats of UV Smooth Prime for the mica UV blockage protection that it would provide, sand it smooth, and then apply a good quality primer compatible with the top coating method that I was going to use.
'O C' Baker says "The best investment you can make is the effort to gather and understand information."
=======================================
From: Robert Reed (robertr237(at)att.net)
Sent: Saturday, August 11, 2012 11:09 PM
To: kis-list(at)matronics.com (kis-list(at)matronics.com)
Subject: Re: Sanding, sanding, some more sanding and so on.
Al,
I looked at using UV Smooth Prime and the PolyFiber topcoat, the Stewart System, and System Three Marine Paint system. The UV Smooth Prime looked real good for a primer but I found too many negatives on the PolyFiber for composites that I backed off on using it. I also have the issue now of not having any available facilities for spray painting so will be forced to find an alternate way to finish. The Steward system definately didn't recomend anything but HVLP spray.
I picked the System Three system because it fully supported roll and tip or spraying. I am using SilverTip Yacht Primer. It is a waterborne, two-part epoxy coating specifically formulated as a tough, below-the-waterline primer for marine topcoats. I figured if it would work for marine applications it should work well for aircraft use as well. The primer does not contain a UV absorber. It does go on easily with a roller and flows out nicely if you make sure and keep your area within temperature range of 65-80 degrees with HIGH 80% humidity. I have my shop airconditioned and used wet towels, sprayed the floor and put a wet towel over the airconditioner. It raised the humidity level and the primer spread out perfectly. If you don't do this, the primer dries so quickly that it will leave marks from the brush tip.
For the color coats I will be useing System Three WR-LPU Topcoat. It is a two-part linear polyurethane coating specifically formulated for maximum performance and ease of use. Available in 12 standard colors as well as clear satin and high gloss. When cured it is moisture, solvent and fuel resistant. WR-LPU contains UV absorbers and will not yellow or lose gloss for years, depending on exposure. (Portions copied from lit) Both primer and top coat are water based. The topcoat can use a crosslinker to produce a super hard finish. Thinning uses distilled water and the top coat does not require mixing with other than water unless crosslinker is added which is only a few drops per ounce. The top color coat paint appears to be much thinner than the primer and with recommend water addition it should flow out much better than the primer. I will be doing some test parts in the next few weeks to see how it flows out in various conditions.
My plan is to use the roll and tip to apply two coats of primer. Sand the first two coats to make sure of filling any minor low spots. Follow with two additional primer coats that will be sanded for top coat preparation. I will then add three coats of color top coats with crosslinker added again using roll and tip. I will let the color coats fully cure and then perform a color sanding to remove any imperfectioins in the surface. Finally, on those parts that I can get to my shop for finish I will followup with two to three coats of clear high gloss with the crosslinker again added. I don't expect to have to finish sand and buff the clear but will if needed. The fuselage is going to be a bigger problem since it is at the hangar and can't be inclosed and protected for painting. I also will have little control over dust and humidity issues. The plan...wait for a warm high humidity rainy week and spend a few days of misery trying to get the paint on. That will not come before late fall or early next spring. Dallas is just too darn dry.
Finally, I know this is NOT the best way to finish my plane. That is a given but there are no paint facilities on my airport and the airport forbids painting (spray) in the hangars. Can't say I blame them. Probably wouldn't make much difference if they did, the electrical available to my bay won't even start my compressor. So my options are limited as are my funds for paying someone to put on a multi-thousand dollar paint job. It is both labor and time intensive but hopefully it will produce a good finish. It won't win any awards but shouldn't make me hide my head in shame either.
Bob
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