Chris Martin
Promoted Users
Hello SPI Friends,
Another problem I am having is nibs in the paint. I have been spraying a single wet coat of SPI Epoxy reduced 25% as a sealer and then two coats of SPI white SS after a 2 hour wait. My test panel is full of nibs.
I exhausted every thing I could do to ensure my booth is dirt free inside, I’m using brand new disposable suit and I put a cotton hood. I ground the parts (even though their are fiberglass Barry mentioned it can help if grounded long enough), I know my filtration system is very good and decent water control (40’ copper pipes, traps, desiccant dryer, Motor Guard coalescing filter, etc. I even installed a gun air filter as last resort insurance). Air pressure control at gun inlet is spot on (checked with digital gage). I don’t have paint strainer at gun and sstrain when loading gun. I use the shitty paint strainers they give you at the store but just ordered the Gerson blue 125 micron ones to eliminate that (will try them next week when I get them). Still, I get nibs all over the surface so I am starting to question if it is really contamination. BTW, I had this issue in the past spraying other urethane products at home (before I learned about SPI) so I am starting to suspect it could be somehting else.
Temperatures and humidity are high at 95+F and 85% but sprayed at a time of the day were humidity is the lowest. Epoxy reduced with slow reducer and SS unreduced with very slow activator.
If I can’t find a solution I’ll just have to fine sand and buff but I am frustrated about the effort and cost I placed on my equipment and still have a gritty surface so looking for advice to reduce factors such as iso clumping or CO2, if it is that. I’m out of ideas.
I will try to get a picture but being white it’s kind of hard to see.
I’m also going to try to to a test by allowing the epoxy to cure enough to 500 grit sand and spray SS. I have seen some dirt in the epoxy but nothing like I see when I spray the SS. The epoxy is going on like velvet even at high temps. Super nice!.
BTW, different subject but to praise SPI epoxy, I flew my airplane with SPI epoxy only for two years. I am cleaning the parts now for top coating and they still look fantastic. Very slight yellowing (almost none) and absolutely no damage on leading edges caused by bug splatter, oil residue and exhaust crap. The parts are sanding super easy and I have not had issues with oil in the primer so far (cross fingers). The stuff is so smooth, and with some gloss, that I have even been told why paint it as it looks so good now! I have to admit, the surface of the epoxy is looking smoother than my orange peely and nib-full SS
Great product.
Chris
Another problem I am having is nibs in the paint. I have been spraying a single wet coat of SPI Epoxy reduced 25% as a sealer and then two coats of SPI white SS after a 2 hour wait. My test panel is full of nibs.
I exhausted every thing I could do to ensure my booth is dirt free inside, I’m using brand new disposable suit and I put a cotton hood. I ground the parts (even though their are fiberglass Barry mentioned it can help if grounded long enough), I know my filtration system is very good and decent water control (40’ copper pipes, traps, desiccant dryer, Motor Guard coalescing filter, etc. I even installed a gun air filter as last resort insurance). Air pressure control at gun inlet is spot on (checked with digital gage). I don’t have paint strainer at gun and sstrain when loading gun. I use the shitty paint strainers they give you at the store but just ordered the Gerson blue 125 micron ones to eliminate that (will try them next week when I get them). Still, I get nibs all over the surface so I am starting to question if it is really contamination. BTW, I had this issue in the past spraying other urethane products at home (before I learned about SPI) so I am starting to suspect it could be somehting else.
Temperatures and humidity are high at 95+F and 85% but sprayed at a time of the day were humidity is the lowest. Epoxy reduced with slow reducer and SS unreduced with very slow activator.
If I can’t find a solution I’ll just have to fine sand and buff but I am frustrated about the effort and cost I placed on my equipment and still have a gritty surface so looking for advice to reduce factors such as iso clumping or CO2, if it is that. I’m out of ideas.
I will try to get a picture but being white it’s kind of hard to see.
I’m also going to try to to a test by allowing the epoxy to cure enough to 500 grit sand and spray SS. I have seen some dirt in the epoxy but nothing like I see when I spray the SS. The epoxy is going on like velvet even at high temps. Super nice!.
BTW, different subject but to praise SPI epoxy, I flew my airplane with SPI epoxy only for two years. I am cleaning the parts now for top coating and they still look fantastic. Very slight yellowing (almost none) and absolutely no damage on leading edges caused by bug splatter, oil residue and exhaust crap. The parts are sanding super easy and I have not had issues with oil in the primer so far (cross fingers). The stuff is so smooth, and with some gloss, that I have even been told why paint it as it looks so good now! I have to admit, the surface of the epoxy is looking smoother than my orange peely and nib-full SS
Great product.Chris
