Steve Noyes
I also have no axe to grind and want to learn the issue.
Are you working with a booth or were they shot in your open shop?
The material prep underneath in looking for a contamination issue was it subjected to something and was it the entire Stewart System prep through finish or was it over another product. What was the temp and did the product sit inside at 65*F for a few days and by any chance knowing you are at a very humid part of the country with shoreline all around you what was the RH when you painted.
How old was your product as I am starting to worry about the finish paint for Jeff Campbells T Craft as we are over a year old on the paint I bought.
Thanks Steve for your insight.
John
Life should not be a journey to the grave with the intention to arrive safely in a well preserved body but rather to slide in sideways, well used up proclaiming "WOW What a Ride"
I had some trouble too, and by trial and error together with Jason's guidance, I found that this material has to be put on in VERY thin coats and allowed to dry and flow prior to the next coat. Otherwise blushing and bubbling and lifting occurred for me. Another mistake I made was slightly over-thinning to get better flow-out. Not by much, but it definitely did not work and was a bad idea. I got blushing and bubbling, and had to re-do.
So what I've figured out is to go for the finest-possible atomization, thin to well within the recommended cup times, stir very thoroughly, apply in thin coats, and wait plenty before recoating. I found that getting in a hurry to re-coat, or putting on a heavy coat were my worst problems.
I haven't put anything out in the rain for more than a few hours yet, and sure hope I don't run into problems when I do.
I have a relatively inexpensive gun, and it definitely does not atomize as finely as the sample Jason sent me showed. I only have the wings left to paint, but I might well invest in a better gun. Gonna stop by the auto paint store on the way home today and see what they say.
Last edited by Gordon Misch; 03-15-2011 at 02:57 PM.
Gordon
N4328M KTDO
I just shot my first wing with Stewart paint. It was so hard for me to shoot the paint the way they want it done. I wanted to spray like I spray everything else, looking into the glare to gauge the amount and speed. It was very hard for me to un-learn how I have done it for years.
Hi John, (flying miss daisy)
i am working in a booth, i am also working on certificated aircraft, so yes, its the stewart system start to finish per the STC. as for temp, yes, everything was above 65', and was done on a nice clear day, free of visible moisture. my product was new. the product i have (we stopped working on the champ until we figure out what is happening) is stored in a place where it cannot freeze, and was purchased last fall. your not too far away, fly or drive to Plum Island (2B2)and see for yourself.
steve noyes
Hi Steve Pierce,
As asked on the http://www.shortwingpipers.org/forum...2153#post42153 forum my pictures are above of my wing problems.
I was picturing something way different. Seen similar problem when stripper wasn't cleaned out of lap joints. I take it the entire surface is not doing this? I would think bad paint it would all be peeling. I wonder how thick the paint was applied and how long between coats? How long was the surface kept at constant temperature after painting? What kind of primer? How long after primed was it painted. How about a chronological run down.
Hi all...
Since your on the topic, I have a question. I ordered my Stewart system supplies last year at Oshkosh thinking I'd have it all used up by this spring. Stuff happened and it looks like I'll be well into the fall or even next spring before I get finished with my painting. The can says "use within 1 year" and I've read at least once here to use "fresh" product.
Anyone ever used 1 or 1-1/2 year old Stewart's paint?
I have it stored at 65 -70 deg.
Al
Don't mess around and get the gun they recommend , Finish Line III. $125 or so, 1.3 tip is all you need.
just a side note/thought,
when using some air compressor supplied HVLP guns(long time ago for me) you cannot use the small quick connects in line(knocks down the flow).... just a thought to check....
actually would be a good experiment if you are having issues to test, making sure your gun is truly getting the supply flow it needs while operating, through connectors, hoses, regulators, dryers.....
I am not kidding...Still using the Wagner! The only issues have been me rushing things... Here is what I do...
1) 12 oz paint...4 oz Cat...add distilled H2O in til viscosity cup runs @ 21 seconds... ( approx 4 oz.) ( Using Wagner vis Cup.)
2) Put product in Wagner Control Sprayer.
3) Turn volume WAY down...lightly mist/coat surface...start timer...about 8-9 minutes later ( using the tacky method)...repeat process...start the time...turn up the air a bit...
4) little heavier mist...DO NOT over DO IT...Always start timer...
5)Slowly increase air/flow...Repeat until you get the sheen you want...
Do not Put toooooo much product on...this is when I have experienced the bubbles...Also I have had better results when I let the surface dry vertical...
Well...been following this thread...and since I am on Spring Break I am working on my project. Completed my wings, and tail surfaces...been hanging in my shop...one for over a year,..the other 8 months...I do not always heat my shop...and the insides have seen -60 this winter...Checked them today...still not issues..
I wish I had a spray booth...that would improve my results..but I have to remind myself...This is a go plane....not a show plane...
I am still happy with my results....Matter of fact...sprayed the interior this morning...hope to spray the fuse exterior Thursday if I stay on task!
I am no expert...just having fun...building a plane with my girls...
I encountered some very similar looking problems on metal. By trial and error, I figured out that I'd put the paint on too thick, and too soon between coats. I found that just misting it on and waiting plenty long between coats it didn't happen. Fortunately, in my case it was a very small area. I'm far from expert and hardly a "real" painter, but for me, so far, those seem to be the big factors in success or lack of success.
I stopped at the auto body supply store today and looked at a Sato gun. Yikes - $595!!! Nope, that isn't a typo - - -
Gordon
N4328M KTDO
Last edited by Bugs66; 03-16-2011 at 12:02 AM.
595? Wow, it has really come down. Was 895 a couple of years ago when I checked. Thats good. That seems to be the best gun.
Bill
New CLEAN air lines?
Jason carries his own when going off to help, so it would be something to check.
I don't know where you've been me lad, but I see you won first Prize!
I was hoping Jason would chime in here...I'm curious to see what he's got to say..
From what I can see, the Cherokee has bubbles mostly starting from rivet heads,valleys, and seams.... hmmmm. That always screams a problem with the prep in my book. The paint coming loose in the valleys of the surfaces is most likely a prep problem as well. If you look at samples of Stewart's Polyurethane that aren't attached to a substrate of some sort, you'll notice right away that it's the most flexible paint you can find! That is a good thing, but also demands that you have a good adhesion, both tooth and chemical to the substrate, as a flexible paint wont help itself stay formed to something as easily as a more rigid paint when dried.
The other bubbles look like solvent popping, from what I can see. Like has been said, it has to go on very light and let dry longer than more common solvent borne paints. It's also more picky on the mixing than the more common solvent borne paints. Like I said before, not difficult, just different! I've "been there, done that" and have some results just like this, hanging on the wall, to remind me. As soon as that underlying "gas" gets trapped, it starts lifting the skinned over topcoat that you've just applied (which hasn't bonded to the underlying coat all the way yet), and when it finally "pops" through the topcoat, you've now got a path for moisture to get under the topcoat.
One day we had some tail surfaces laying in the shop, drying, and one of the guys was on the other side of the hangar (60x60), and squirted a pulley with some tri-flow. The sun was shining and you could watch a little cloud of tri-flow migrate ALL the way across the shop and head right to those surfaces, just like a magnet!! Needless to say, we had a contamination problem with them when we went to paint them.... and from then out, nothing comes out of the paint booth until it's topcoated and dried. I was amazed that it took such a small amount and that it had travelled so far! It explained alot of previous problems I'd had too!
One of the things that I don't see mentioned much is airflow over or through the painting area. A booth that has no airflow isn't going to do you much good for getting the finish to gas out. It doesn't have to be a hurricane, but it definately needs some airflow!
Like I said, this is my 2 cents worth, and worth what you paid. Sorry to hear you both had trouble with the product. I've used it for years and love it!!
John
Last edited by Hardtailjohn; 03-16-2011 at 10:49 AM.
Quick Stewarts waterborne story.
Last night I was priming some metal parts with Stewarts. Using a friends really super nice 10-light professional booth. I was misting pretty lightly and did all my parts. He was watching from the window.
After I was done. He said, "I don't like the way you were painting." He walked in grabbed my gun and did the lower cowl over and the top cowl. He had huge runs IMMEDIATELY down the whole part.
We walked out. Checked out the parts after dry. He was sick. He said all my parts were perfect, and we have to strip and redo the cowls that he did. Lesson learned for him. This is a different animal. His planes in Stits are show quality, he wasn't ready for the different type of painting.
I'm not upset at my un-named friend. I'm not upset at the product. It works really well for me. It happened just like every single person I've heard for the last two years. If you've painted solvent and are good at it. You have some unlearning to do with this system. It's not a bad system, actually it's quite impressive, you just have to learn a new spray technique. Maybe spraying blind folded would help? I keep hearing solvent guys are looking for a wet look behind the gun, while this "water" system looks dull and dry, then later settles into a "wet look."
Now for a little do-over. I'm really appreciative that my generous friend is letting me use his booth and equipment. He about passed out at the gun clean up and walking around in the booth with no smell. He couldn't say enough nice things about it.
Cheers.
Well said Cal!
I've been following this thread from the beginning and it is a good one. I would not be surprised if Poly Fiber comes out with their own system to compete with the Stewarts. The "old timers" I talk to would not even consider using the Stewarts. I think Cal said it best in that you have to be willing to re learn your skills. I'm not going to armchair quarterback the Cherokee problem. I think it is just sound all around general advise if you choose to use this topcoat system.
I have heard guys say that they start their covering inside the booth and don't take the parts out until it is completely painted and cured because of contamination. What I want to know is that with guys that are building their own booth out of wood frame lined with heavy mil plastic, They leave their parts in there for an extended period of time, isn't there a chance of dust coming in while they are going in and out during the covering process? How do you keep the dust out?
Regarding waterborne specific paint guns I think it may just be a sales pitch by manufactures. I use a SATA 3000B digital ($550) paint gun, Dan Stewart uses an IWATA LPH400 ($500) and we both have used the DeVilbiss Finish line III ($140) None of these guns are "waterborne" guns. I called IWATA to talk with their engineers about their new top of the line paint gun the "Supernova" which is available as a base coat or clear coat gun and also available in a LVLP or normal HVLP. They recommend their clear coat gun for shooting our single stage top coat paint. The LVLP gun will work on 19 psi and 10 cfm. I was told the Japanese had the best LVLP guns and IWATA is probably the leader of Japanese paint guns. I know people are on a budget but seriously the only thing other people are going to see is your paint job. Why skimp on the equipment used. It's a fact that the SATA and IWATA guns do a better job of atomizing paint and they have a larger fan width which really helps production time. If you spend $500+ dollars on a gun I'm not going to promise it will lay down a perfect paint job. Technique is mostly what affects the finish not the gun but a great gun sure helps. You can sell a top of the line paint gun when you're done with the project for almost as much as you paid for it. A less expensive gun has almost no resell value. It is also important to have clean dry air and hoses for painting. Only use 3/8" rubber hoses and the only quick disconnect should be a special high flow fitting between the gun and air hose. Waterborne paints are all about being able to atomize the paint into the smallest droplets possible. If you hold the gun to close you can blow excess air into the paint film which can cause pinholes, if you hold it back to far the paint will loose some of it's atomization and fall to the surface in larger droplets creating a dry or orange peel affect. What I'm trying to say is PRACTICE!! and not on airplane parts. Practice on stuff you can throw away
The paint is not hard to use and once you understand the parameters it's extremely forgiving and you can get away with stuff that would totally ruin a solvent based paint job. If you research online about auto body shops switching to waterborne paint they all had to go through a leaning curve but once the figured out what they were doing wrong they absolutely love shooting waterborne paint. Waterborne is the Future of painting and I have spoken to many professionals that have no desire to return to solvent based products.
For the thousands of gallons of paint we sell it is surprising how FEW problems our customers have spraying it and 99% of those problems are equipment or technique related.
Jason
I bet if we could go back in time Ray Stits caught all kinds of grief from the dope guys when he came out with his system.
Steve, I thought of that too. I think you are spot on. It will be interesting to see if and when Poly Fiber releases their version of waterborne.
I think Jason is right that the future of painting is in the waterborne...just strictly based on the EPA aspect. With Poly Fiber being based in CA and with this state's strict EPA standards, sometime I wonder how they do it. Only time will tell, I guess.
Sorry about the thread creep...
my main thing I adjust paint by (not this stuff, no exp yet) is when things are going great, STOP and go over to your test paper hanging on wall and shot a couple 3 or 4" long stripes, and look at the edges in the paint dots for the size of the atomized dots, THAT is what you are trying to duplicate each time... paint viscosity and guns will change as you use them, but if the dots are the right small size you will never have runs, sags or such(unless you try hard)
Well, I started this thread and since then I have painted approx 3/4 of my ext of my Murphy Rebel. I have no real prior experience painting and have found the paint to be easy to work with IF you follow the instructions to the letter. I have gotten some slight orange peel a few times and each time it was due to not putting enough paint on. Being afraid of a run has made me apply too little paint and each time I sanded and then repainted and it looked great! My compressor is rated a few CFM's less than what Stewart calls for and I guess it hasn't been a problem. One thing I really like is going to my sink and cleaning the gun with warm water! I also like the lack of dangerous fumes although it does have its own odor that isn't so great. Craig www.alaskanrebel.com
I would recommend leaving the painted parts outside in the weather just so that you can be sure that the paint actually set correctly. I am sure it probably will for you because you have followed the instructions to the letter. It seems as though many people on this thread have run into some minor issues with water intrusion but caught it early enough for it not to turn into a major problem. Our parts for my fathers cherokee looked great inside but once we put the plane together a few months after we had painted and put it outside that is when we ran into trouble. I just don't want to see anyone else go through all of the efforts of painting and then run into problems after you had thought you did it correctly.
I don't believe you have a water intrusion problem. I believe you have water trapped under the cured polyurethane. Once the catalyzed polyurethane is cured water is not going to penetrate it and this will take place in a day or two.
Well I don't really care what you believe I was just giving him a recommendation because if he has any problems with the paint laying down correctly it would be better to find it now than after he has the plane together. That is all. I wasn't saying anything else Steve just based on my experience with the product I would have liked to have found the problems prior to putting the plane back together so I could have repainted it.
Snowy, checked out your site and nice job on paint! Won't be long now!
Just got done putting the Fabric on my exp project...love it when it starts to look like a plane...Eco fill today...
Wondering if there is a shelf life on the glue...I am sure there is...started with an older bottle...could not get it to grab very well on metal...would pull away when I started to shrink...tossed the older glue, opened a new quart...seemed to work better...
Great stuff...Hopefully painting on Sunday...have to go to Anchorage to pick up the family from their spring break in the sun...
I found that I have troubles with the glue when I get in too big a hurry. If I put it on the metal in moderate thickness AND let it dry, it worked real well. But if I tried to put it on too thick and didn't let it dry enough, it just wouldn't stick - it just lifted off the metal and contributed to a not-so-nice vocabulary. I think for me, the biggest part of the learning curve is learning to wait long enough. I think that's because we're used to solvent evaporating relatively quickly, but the water takes somewhat longer to dry. Just my (limited) experience - -
Gordon
N4328M KTDO
Ideally you want to wrap the fabric around an edge, or tube and the glue should be on opposite side. That way the glue is in shear and not tension. Also make sure it is dry like a post-it note.
Aeronca65CA,
For a fellow on this website for what 2 weeks you are real gem. We know you are ticked off and frustrated but to a fellow that has not contributed an iota of useful information like yourself I can only hope SJ mails you back your money and you go over to back country pilots before your attitude prevents folks like Pierce and MCS Mike from posting cause its not worth dealing with flak from raving lunatics. Steve Noyes was a gentleman and shared information with us to help provide clues to a solution to a potential problem. Now I as one would like to know how to prevent it on my rebuild.
Steve Pierce since you have probably the path to the problem will you expound on what you mean by the polyurethane trapping water. I assume since most folks having issues with the process are the most experienced with painting then it comes down to too much product being waterborne trapping water under the paint. Am I on the right track?
I saw one post where the fellow is real happy with the product and he mentioned orange peel. I understand that to be air delivery issues and air volume causing inadequate atomization of the paint.
A65 if you stopped being so mad maybe you could help and we could help you.
John
Life should not be a journey to the grave with the intention to arrive safely in a well preserved body but rather to slide in sideways, well used up proclaiming "WOW What a Ride"
If you are in a hurry for the bed layer of glue to flash off so you can start attaching the fabric I would hit it with a hair dryer or heat gun on low. It's noticeably slower to tack up when below about 45 deg or in cool temp and high humidity. I try to keep the shop above 50 when doing fabric work and above 60 when painting.
Jason
Sorry it took me so long to join on the Stewarts Cherokee paint problems. Ihave spoken to both Dan and Jason about the problems. I followed the instructions as close as possible. Today I went to the airport to work on the plane [Sooner or later it will fly again} I think I have two diffent problems. On the tail {where the large blister was} the paint has seperated from the primer. On the left wing root it appears that the upper layer of top coat has lifted. The rest of the at this point anyway seems to bonding ok. A question I have is why does it seem that only the upper surfaces are lifting? I used a rotator when I painted. Overall I found the Stewarts process fairly easy to use. I wish that when they have changes with the procedure that they would send an e-mail to everyone[ ie new tack rags and a few other changes] since I started this project almost 3 years. thanks for time Don Tewksbury
The only place I have any kind of a lifting issue is right where I was afraid it would be. Before I closed my wings I used Corrosion X on the inside. After the wings were up on the wall while I was building the fuselage I started noticing that it was dripping out. Long story short, do not use C X on your plane anywhere you expect to paint. I only have a 2" x 1/4" area where the leading edge joins the wing. Hopefully I won't see any other ones! I took some precautions given me by the Corrsion X folks and Dan at Stewarts. We'll see. CW
thread fork!!!! (we really need an emoticon for this)
so this thread helped answer something with regular solvents based polyurethanes I had noticed...
when people over accelerate a paint the adhesion is poorer..
I bet this is the same issue, that the paint is hardening/curing on top of the carrier before the carrier evaporates.....
I always explained it as not giving the paint time enough to get into the pours/sanding scratches before hardening, but now I doubt it.........
I bet this is the same type deal????
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