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When is enough Ecofill coats?

Posted: Monday, October 29, 2012 5:34 PM Quote
This might have already been addressed in the forum but I thought I would ask. I have applied 1 cross coat with foam brush and 2 sprayed cross coats. I can still feel and see the fabric weave even after some light sanding with red scotchbrite. My question is if you have a good rule-of-thumb about knowing when you have put down enough Ecofill coats? Are you done when the weave is filled in and flat or what? Thanks, Dave
Posted: Tuesday, October 30, 2012 11:06 AM Quote
If experimental its up to you. If STC'd I think you need three spray cross coats.  The brush coat only fills the weave, the spray coats and where you get build up.  

I used three sprayed cross coats.  If its a fuselage or something you can see the backside of the fabric,  Hold a 100 Watt incandesent bulb up near the surface.  If you can see light through it spray another cross coat until you can't. IF you can see the light on the back side you should have enough UV protection.  You can always spray more for a smoother surface.  I though 3 sprayed cross coats provided a really smooth surface.

I used an orbital sander with 320 grit hooked up to my shop vac and sanded between each sprayed cross coat.  That worked really really well but I must Stress STAY AWAY FROM THE RIBS or anything hard under the fabric.  This is just for the open bays!  The orbital sander will really speed up the process.
Posted: Wednesday, October 31, 2012 12:20 PM Quote
If you feel like when you sprayed on the EkoFill you had a ton of overspray and the surface looked very dry and possibly rough like sand paper after spraying you most likely held the gun too far away and did not get a good coat of EkoFill on the fabric. When spraying out EkoFill try to get a satin wet finish with just barely enough shine to see the reflection of the spray gun as you move across the surface. Too wet and it's going to run, too dry and you have to sand it smooth. The proper semi-wet coat looks kinda crappy when applying it but will flow out nicely.

When sanding and you think you're back down to the weave of the fabric look closely... If it's white that's fabric, If it's light grey then you have not hit fabric yet. When sanding EkoFill it goes from dark grey to light grey. The EkoFill builds vertically mimicking the weave of the fabric so as you sand it you initially get what looks like the weave coming through, Sand a little more and it should smooth out where where the little dark spots go away and it's all light grey. I highly recommend buffing the surface with red scotch-brite after sanding.

Be sure to first check that you are not getting into the fabric. No 2 painters will spray the same way and how much you have on the surface and how far you can sand is very specific to each persons work.

The paint has a lot of UV protection built in so even if you only get a 75% of a total light block you're still getting great protection when you spray the paint on.

Jason
Posted: Tuesday, December 4, 2012 7:35 PM Quote
As Jason says, everyone sprays differently so it's hard to prescribe a one-size-fits-all recipie for the ekofill.  It seems that I end up spraying on the light side, regardless of my attempts to try to really "load it on".
My sequence goes like this:

1. brush coats with a foam brush.  I brushed till the brush was basically dry in any given area to make sure the paint was in the weave, not on top.
2. Iron all pinks (I use  225-250 degrees with a teflon strip between the iron and the surface to keep the primer from being messed up... really works well), CAREFULLY get any big chunks of foam brush, glue, etc out of the brush coats. hardly any sanding (if any)..  maybe some scotchbrite scuffing to help the next coat stick. It takes nothing for the sandpaper to hit the weave of the fabric.. the tiniest hint of white and you'll get the dreaded fuzz.
3. tack cloth/air blow, followed by an alcohol wipe down.
4. spray a cross coat.
5. iron all the pinks again. Yes this is tedious.
6. sand.  don't get too crazy, just sand enought to begin to smooth over the inevitable small glue blobs and get a generally smooth surface.  Just get the sharp edges off the pinks.  Too little sanding here is much better than too much! I still see dark grey in the bottom of the weave when I am done with this round of sanding.. if I go for the totally smooth, no-weave type of sanding I hit the fabric every time.  I use 320 paper in the corners, on the tapes and on the pinks.  I use a DA sander w 320 on the open areas, and a red scotchbrite over the stitches & "hard" areas (LE, TE, etc). When done sanding, I quickly scothcbrite the whole piece.
7. tack,wipe, spray another cross coat.
8. now really go to town sanding/scothbriting. I'll try for the no-weave look and usually get a bit thin here & there.
9. tack, wipe, crosscoat #3.
10.repair any fuzzed areas (spray, sand, repeat as necessary).  Ocassionally I will do a quick coat over the pinks only if they're just a bit too "un-smooth".  once you're happy with the pinks, fuzz repairs, and general finish, it's time for a scuff and the topcoat.

Jason is able to complete the process in two sprayed crosscoats... Wish I could too! would save a lot of time, but for me a planned 3 crossccoats is less frustrating than a botched 2-crosscoat approach.

I'm using a tekna prolite with 1.4 tip, TE10 cap, 1/4 turn fluid, and 32psi.  Just did a wing using a Devilbiss "plus" gun, 1.4 tip, about 3/4 turn, and had about the same coat thickness and quallity of finish as the Tekna gun. (both had nice results)

Just my method, chime in with any input!!