Questions for Latex Lovers

[dholly 718]

Yeah what you kinks do in the privacy of your own home I don't much care,

HOWEVER, with regard to latex paint on aircraft:

• Q1.) Anyone use Sherwin Williams All Surface Acrylic Latex Enamel PRIMER ?
• Q2.) Anyone use Sherwin Williams All Surface Acrylic Latex Enamel as a TOPCOAT ?
• Q3.) Anyone use the two together on Ceconite fabric covered with AirTech system ?
• Q4.) Anyone lay down an extra PolySpray cross coat between latex primer and topcoat ?

[NorthIdahoAvidflyer 374]

 Of course you went there dholly!!

[Allen Sutphin 705]

I've used the Sherman Williams top coat on Stewarts System products. Their high gloss paint isn't high gloss on Eko-Fill, but it does work. I'd use Sherman Williams grey primer on bare fabric. Make you up a little 3'X3' test panel and give it a try. Too many factors involved to be completely sure. Age of poly stuff, smooth or rough, etc. I would be willing to try SW on top of Eko-Fill if I didn't care about a high glossy finish. Of course, a stump jumpin' Avid/Fox doesn't need a glossy finish, only takes away from the character of the plane.

[dholly 718]

Many different aircraft covering systems. Poly Fiber is a vinyl based covering system. Air Tech and Superflight are urethane based systems. These three were designed to create a chemical bond. Stewart's uses water borne urethane for a mechanical bond.

I would note that the SW All Surface Primer label states "not recommended for use on vinyl".

Therefore, I wouldn't use it on a PolyFiber covered plane with bare fabric. Just a heads up to be very selective and ensure whatever primer one planned to use actually is compatible with vinyl if painting over bare PolyFiber.

That said, the SW primer thinned 20% brushed and rolled onto bare AirTech covering great. On the first brush coat, I used new lint free rags wetted with water as a tack wipe on the cleaned wings etc. to wet the Ceconite slightly in an effort to suck the primer into the fabric for better adhesion. Very light sanding w/ 400 grit dry before rolling the 2nd coat. Both flowed out nice and smooth, 2nd coat will not take much sanding thankfully. I'm going to set up my homebrew spray booth for another couple primer cross coats to fill weave, sanding after each cross coat, then spray the top coats.

This plane is on floats and spends it life on the ramp. UV ratings on exterior grade acrylic latex enamel are pretty darn good, but still wondering if shooting on some Polyspray would be worth the effort, assuming it's even compatible with latex?

[marcusofcotton 51]

I'd stick with what was designed to work together, forget the Polyspray as adhesion to the others may be questionable.

[dholly 718]

Some progress pics. I did have the white SW primer tinted gray. Everything was painted out in the open, the bugs and fuzz are staying away, knock wood. If you zoom the tail surfaces pic (2nd coat, pre-sanding) you can see there is a long way to go to fill the weave.

[marcusofcotton 51]

Filling the weave just means more weight and future cracking 

[dholly 718]

Actually, it means adequate UV protection!

[Cloud Dancer 69]

I'd like to see someone cut some fabric pieces "flag" sized and paint it on both sides with these experimental paints and then raise it up the flag pole and test it. Constant exposure to the elements would give you long term results in a shorter time span. Wind whip, rain, snow, ultraviolet, temperature changes and more. A base could be established by painting a "flag" with recommended number of coats of a conventional aircraft paint system. If it holds up on a flag it should last a long time on an airplane.

[CoClimber 33]

I'm testing PPG Gripper primer on my rudder.  Yesterday I sprayed high gloss latex my wife picked up at Ace Hardware (she works there).  I can't remember the brand but she says it is owned by SW. I'll check the results when I get home tonight.

[1avidflyer 1983]

One thing that comes to my mind is the fact that aircraft covering systems are designed to last for many years with the plane parked out side in the elements.  I think very few of our Avids and Kitfoxes spend much time outdoors when they aren't flying.  Certainly that could have some effect on how we approach the subject of coverings and paints.  JImChuk

[Allen Sutphin 705]

I'd like to see someone cut some fabric pieces "flag" sized and paint it on both sides with these experimental paints and then raise it up the flag pole and test it. Constant exposure to the elements would give you long term results in a shorter time span. Wind whip, rain, snow, ultraviolet, temperature changes and more. A base could be established by painting a "flag" with recommended number of coats of a conventional aircraft paint system. If it holds up on a flag it should last a long time on an airplane.

I did that with Poly-Fiber. Its been 6 years and fabric is reasonably good. It lost its semi gloss but held up pretty well. I can say after about 10 years of being outside year round I'd be testing the fabric constantly. The paint seems to start to fail after 6-7 years so its the only thing that protects the fabric and when it fails, the fabric isn't far behind. Plus, being stored outside, the tubing does start to weather even though its covered.  My advice is after 10 years outside, start planning on a recover. Inside storage is a different story. Latex paint is a crapshoot as far as lasting 10 years inside or out. Fading is normal.

[dholly 718]

Not sold on Latex. Been working pretty regular over the past few weeks on this paint job and it can be very labor intensive if you're trying to do a good -rather than a cheapo rush- job. Boatloads of sanding between coats. Here's a quick update.

The Sherwin Williams All Surface Acrylic Latex Enamel Primer sticks to Ceconite and your hands, clothes etc. like crazy. 1st coat is thinned ~20% and brushed into the weave like PolyBrush. You can see it on the inside of the encapsulated fabric fibers. 

2 more rolled coats, thinned ~10% and sanded w/ 320grit after each coat. 3 more primer coats sprayed @ WB.5.125 viscosity (see: http://wienerdogaero.com/LatexViscosity.php) and sanded w/ 320grit after each coat. Min. 4hr re-coat time on this primer but sands easier if you let it cure overnight. *Note: AirTech uses polyurethane based products/process. Both SW primer and topcoats latex paints used here are labeled 'not recommended for use on vinyl'. Therefore, I would caution regarding use over poly fiber's vinyl-based products/process.

Color on this KF was to be color matched to existing float colors and scheme. Unfortunately, the SW All Surface Acrylic Latex Enamel deep color bases did not support the desired yellow topcoat scallops so we were forced to upgrade to SW Pro Industrial DTM Acrylic Latex Enamel. This is a direct to metal formula and also sticks like crazy. Yeah, I know, what was I thinking? Red and yellow, the two hardest colors to cover.

Unfortunately, DTM is also a b*tch to sand. After spraying the last coat on everything, I went out to shut off lights for the night and found paint runs on one side of the fuse. The very last thing I painted. Didn't do anything different, but we had an unusually cool overnight and I can only guess the cooler temps that evening didn't allow the paint to flash off as quick. In any event, 2 more days to sand runs, re-prime and re-paint and I still can't get rid of them entirely. Grrr. The rest looked great. If I were to wet sand and polish, it would look spectacular.

Would I do it again? No. Well, maybe if I wanted a hot and dirty touch up or re-do on a previously painted plane. Not on a newly covered plane. In hindsight, a couple coats of AirTech 2-part topcoat would be sooo much faster and well worth the added cost for poly and solvents plus $100 for a positive pressure mask. IMHO, your time has to be worth something. Of course, YMMV.

Edited 29 Sep 2019 by dholly
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