PDA

View Full Version : The painting process



mcguif0a
01-16-2009, 02:54 PM
The paint booth is finished and so the paint job will commence shortly after the cold snap is done with Florida.
I would like to hear how many coats of the poly brush, poly spray and poly tone people used and some total estimates on the quantities of each that it took to complete the work. Sometimes I get the feeling that the poly fiber book is trying to sell me more than I really need.
All recommendations about technique, equipment used, other helpful hints are needed. I still have to get the HVLP system so which ones work?
Thanks, Tyler

Dave S
01-16-2009, 08:03 PM
Hi Tyler,

You are getting to the point where all the work starts to pay off :). When the undercoats and paint start going on - a person can sit back and start to see something that looks like it is getting done!

It might seem like a lot of gallons of material. I kinda thought that too - especially since I have done a lot of auto painting - car painting didn't take all that much by comparison. However - this isn't like auto painting. First off - Each gallon of poly brush & poly spray has a whole lot more solvent in it than solids - most of each gallon evaporates. Second, there is a reason for all the repeated coats - that is how the system works well. I have seen a couple jobs where people skimped on poly brush and poly spray - it sort of ends up looking like the weave of the fabric hasn't been filled - then the topcoat looks a little coarse too. The weave needs to be filled reasonably well to get a nice surface; and, to make a good seal to the elements. The Poly spray is particularly important since that is what keeps the sun from rotting the fabric - what they say in the poly fiber book about checking out the adequacy of the polyspray by shining a bright light through the fabric is good advice - if you can see the light - it needs more.

I found that the book, while it was a little generous, was about right - I didn't have a lot left over. I also listened to the polyfiber rep - a local guy who carried their product and did a lot of tube and fabric aircraft rebuilding - he indicated that it can be a temptation to go too light on the coatings. If you are concerned about getting too much material - there is nothing wrong with getting some - seeing how much you use - then estimating the rest and getting some more as you progress. The polybrush can go on in stages - same with the polyspray - as long as you keep the surface clean if you leave it for a couple days to get more supplies. If you have a local supplier - ask if they will accept returns of unopened cans - sometimes they will and that will ease the concerns. I had a a gallon of poly brush and poly spray each left over - ended up trading it off to another pal at the airport who needed it.

Sometimes people are concerned about adding weight by having many coats of material. That is a judgment call to some extent and certainly a little more or a little less will both work. Probably a good thing to not skimp on the poly spray for the aforementioned reason. If a person is concerned about weight - going light on the polytone for a topcoat compared to going heavy on the aerothane will probably make a difference of a few pounds - the topcoat is just for color and shine (or matte finish).

Good luck with your project :) - We all do things a little differently - but I found that the Poly Fiber book was pretty accurate; and, I tried not to deviate from the technical recommendations - figured that the Polyfiber folks probably knew their products pretty well.

Sincerely,

Dave S
Kitfox 7 Trigear
912ULS - warp drive
Testing completed......climbs like crazy at minus 10 degrees F.