Id like to here everybodies thoughts on this. Lately my gloss coats have been coming out beautiful. I used to get separation, tits, accumulation of resin from runs,all kinds of ugliness. I would mix it really hot because thats what some literature said to do with gloss/finish resin. I started mixing it at 1 - 1.25% and now all those blemishes kind of take care of themselves, or so it seems. On a 70deg. day it takes about 2hrs to harden but in that time the resin flows out evenly, bubbles rise and pop, wax comes to surface evenly, and no tacky streaks. Im using the same resin just less catalyst. I got the idea when browsing a website about polyester resin, it happened to mention separation can occur when resin is mixed too hot, so I tryed it. Anyway, just thought id share my experience cause i used to kind of dread the gloss coat process but now its kind of exciting.
Not only does the resin seem to level itself out and take car of the dimples, bubbles, streaks and stuff but you should be able to pull the tape after the excess starts to hang like a sheet from the rail line. Taping on this edge while glossing the other side can produce an invisible seam. I’ve glossed boards that required no wet sanding and nothing more than a bit of hand polishing. It is possible to purchase resin with special additives that increase its surface tension, making the resin even more capable of self leveling. If the board is well sanded and cleaned the result is perfect gloss coats without wet sanding. Sand the hot coat to 150 grit, wipe clean with a soft cloth and acetone, tape (use the right tape so the adhesive doesnt dissolve and mix with the resin), and then WITH VERY CLEAN HANDS run your palms over the whole surface to be coated. If you can feel something on the surface it will cause an irregularity in the gloss (your hands can feel things that are 1000 times smaller that the things you can see). The hot coat is applied with a wide brush and the focus is on coverage without big puddles. Dont mess with it too long as you will begin to leave brush marks. Come back in about 45 minutes and pull the tape (the resin should be thick but still kinda liquid - leaving a smooth edge where the tape comes off). Let it dry completely before flipping it over. Resin made for glossing dries slowly to allow for leveling. Flip it over and do it again. Its ideal if you have a room with complete dust control so no goodies get in the gloss while its setting up. Good Luck!
Howzit Don, youmention it takes 2 hrs for your gloss to harden but how long is it from the time you catalyze the batch till it kicks. My glosses also come out beautiful but they kick 10 mins or so after catalyzing. Another thing that will cause separation is if the gloss coat is to thick. Aloha, Kokua
thanks for responses, both of you are light years ahead in knowledge. 10 minutes was about the time my gloss coat was mixed at before and whatever nastiness was there when it went off stayed there. Now when im done glossing i shut the door and monitor the 2oz or so i have left it starts to gel at about 45 -60 min and shortly there after it does its exothermic thing and really hardens, this is at about 68-70deg F. I think i used to be kind of stingy with the resin before also and trying to spread it too thin. I also like the invisible tape line possibility Ill have to try it soon
streaks,why do i keep getting them? is it the S/A not mixed in enough? if i strain it will it stop???aaaaahhhh
I was plagues with streaks tacky resin in both my hot and gloss coats for a while. They just started for apparently no reason. I hadnt changed anything inthe process. On a tip from Swaylocks I started adding Catalyst instead of allowing the UV cure and I have no more streaks. They seemed to be most prevalent on darking airbrushes and fabric inlays where in retrospect i guess the darker colors would accelerate the UV cure. Maybe try less cat. or as Kokua suggested a thinner coat. I used to not use enough and mine would be too thin so I guess there is a happy medium somewhere. I think this thread is getting kind of buried hopefully someone else responds cause i dont know anything about adding S.A. good luck
Howzit Teddy, I run it all thru a strainer then mix it, when you stir the mix are you also running the stir stick around the inside wall of the cup. That was one of the first things I was taught about mixing resin. If the gloss resin is too thick it will separate. Try this, Strain the gloss resin,add 10% styrene and 5% S.A. and mix throughly. Add your Catalyst and apply to the board. do your cross strokes to even our the coat and brush the board 3 times. This is the procedure I use and it works for me. Aloha, Kokua
Kokua nailed it as usual.The streaks you speak of may just be common wax streaks that rise when the resin kicks,they are no problem as they polish out.Some folks are used to seeing boards in retail shops with that mirror shine that only comes from machine polishing and therefore feel that they are doing something wrong which is not the case.Hope this helps. R.B.
…Most of the zits,and contamination comes from your brush,not airbornes. …I have gotten great glosses in some crapping,dusty places.Here’s 3 simple rules to follow… …rule1…no wind/air movement.none,DEAD CALM…GET IT!!! …rule2…Making sure you got the right mix,…too long of a set-off will allow crap to accumulate in your coats. …rule3…Clean your brushes correctly!..Or you might as well go sand finish. …also this tip…the better your racks are leveled,from side to side,and front and back(side to side is the most important).The better chances that you won’t get separations in the coat(s) as the coat(s) set-up. …Herb
Howzit Herb, My shop has a dirt floor which should make for terrible glossing but it doesn’t. I just make sure the last thing I do before appling the gloss is run tape over the board to remove the dust. Aloha, Kokua
After your gloss ing what sand should you be able to do? we alsawys have to start at 220 then 320 and so on… because i think my brush leavs all kindsof hairs and room is dusty. i would like to not have to 220 theboard. whick brushes work best… and i know you are gonna say the expensive ones so i better quit bein cheap …hehe… glosses are gettin betteslowly tho
…Archive this info. lots of great stuff from some great builders. …keep building…Herb
Howzit John, The brushes I use come from Fiberglass Hi. and they call them Aussie brushes. These brushes hardly shed bristles at all, Maybe a little the first couple of uses. They have a white plastic handle and run about $7.00. There are others that also work so do as Herb says and check the archives for more info. Aloha, Kokua
I do fine with chip brushes but I buy a dozen at a time and paint the bases of each one (with a bit of hot sanding resin) when I get them so that the bristles dont get loose when I gloss. Theyre cheap and I can throw them away. I just dont care to keep a bucket of acetone around to clean an expensive brush.