So I’ve been spending a lot of time making wood fins these days and since I don’t have any roving I’ve been pulling out strands of cloth to use instead. Works well but is very tedious and makes a mess. So I ordered the 10 Bundle Pack from Fiberglass Supply. I had ordered a small amount of roving from them before that instead of looking like the picture on their website, looks and feels like dental floss. And DOES NOT GO CLEAR! So I just opened up my new order and they sent me 40ft of the same stuff! What exactly is this stuff? Because I’ve used it once on a glass-on fin and despite soaking for a long time, it never went clear and the fin looks like crap. When I ordered a center Probox from Greenlight Surf Supply they sent me a length of roving for the install and it look completely different, much more like fiberglass, and was a lot softer. The stuff I have now is nothing like that.
So do I call them up and go WTF? This is such a pain and all I wanted to do was save myself having to take apart cloth to make my own roving. Thanks for any help you can provide guys.
The bead on the wood fins and then the base/fillet on 2 sets of bonzer runners. I think I might need to make the call this afternoon because I don’t have a lot of time to finish this boards.
The stuff you are talking about sounds like endless roving that is typically used in a chopper gun in production fiberglass shops. It does not behave very well for fins, even though it is very convenient. Part of the problem has to do with the “sizing” of the fibers.
My preference is to buy a piece of 24-oz woven roving (very heavy fiberglass) and pull strands from it. The reason this works so much better than endless roving is that this material is “sized” with the same material as your regular fiberglass cloth and therefore wets out much easier. But it does still require pulling the strands, but because of the weight of the fabric these strands are much thicker than regular glass, so it requires fewer strands.
This is what I use for the beads on any wood fins I make and it wets out really easily, especially when compared to endless roving.
This is also what we use when doing a ProBox install when we are looking for maximum reinforcement of the resin.
You can use that stuff, just mix up a small cheater batch of lam resin with a bit of styrene mixed in and use that to wet out the roving. Then come back with your regular bucket of lam and saturate good. That’ll wet it out and as long as you go back and forth thoroughly with your brush and the regular lam resin strength won’t be compromised…
I’m using epoxy. Would a cheater batch of that thinned with denatured alcohol be the way to go?
Here’s what they show on their website:
Here’s what I have:
Kind of hard to get a good picture of, but it’s very loose, not soft like fiberglass, kind of crunchy, and doesn’t seem to wet out even when soaked in epoxy for 10 minutes.
I wouldn’t have a problem with taking apart woven roving, but the only place I can buy it around here charges $30 for a 50" x 36" piece.
I’m using epoxy. Would a cheater batch of that thinned with denatured alcohol be the way to go?
Here’s what they show on their website:
Here’s what I have:
Kind of hard to get a good picture of, but it’s very loose, not soft like fiberglass, kind of crunchy, and doesn’t seem to wet out even when soaked in epoxy for 10 minutes.
I wouldn’t have a problem with taking apart woven roving, but the only place I can buy it around here charges $30 for a 50" x 36" piece.
What you have looks like it should go clear. If you pull off about 36" of roving (enough to do a thruster), however many strands you need to make your fillet, take it and act like you’re cracking a whip. Hold one end and pop it several times (maybe take a bit of 3/4" tape and wrap the end you’re holding), this will seperate the fibers and help it soak resin. Like someone said above, it won’t go totally clear in epoxy, but should be acceptable clarity. Another technique is to cut it to length for each fin, then take a fin tooth comb to it, more tedious than the first technique, but effective.
I am pretty new to the whole shaping thing, but last night I was finishing up a board with wood fins and using the roving you are describing and it NEVER went clear. I have done all my boards with epoxy and this was the first time I used the fin roving. Your description of the roving is perfect, it isn’t very soft to the touch at all, and it is sort of crunchy like. I figured it was no big deal, but this morning when I checked on things the roving wasn’t even close to being clear. It was very cloudy and milky. I even tried to wet it out lying it flat and really letting the epoxy soak in, but it never seemed to go clean. I would stay away from it for sure. This is the last time I will use that kind of fiberglass. I guess I am in the same boat as - back to pulling strands…
Oval patches cut on the bias can be used for glassing on fins and arguably provide better support.
Using laminated glass layers with overhang around the edges, resin fill, and glass panel laminated to the other side, you might not need glass rope in your bead. I think Austin’s dad posted recently that they don’t use it on their wood fins.
Howzit hand-shaper, Buying the woven roving is the best way to go since it’s good for fins and a lot cheaper than rope. A yard of it will last for a long time and is easy to cut and unweave, used it forever.Aloha,Kokua
Howzit hand-shaper, Buying the woven roving is the best way to go since it’s good for fins and a lot cheaper than rope. A yard of it will last for a long time and is easy to cut and unweave, used it forever.Aloha,Kokua
Yep, it’s almost an endless supply! I’ve had a couple yards for about 7 years now!
I’ve found that roving varies quite a bit, even from the same supplier. The trouble with the bubbles and clarity using roving isn’t worth the hassle to me. Roving doesn’t add any strength since doesn’t go up the fin sides far enough. I just make fillets using resin/cabosil filler and then glass the fin on with overlapping layers each side. Cabosil will vary in clarity also, so you may have to experiment. To eliminate dry spots in the filler, mix it a day ahead (uncatalyzed of course) and seal the container. If you’re using the roving for beading, you can use filler here also. If you want it super clear, see Austin’s thread on the wood D-fin which doesn’t use roving.
I had the same trouble with their roving and epoxy…major bummer after you put so much effort into custom wood fins, etc…I beat the snot out of it and it was 80 degrees out, etc. and it still is not only milky, but also shows strands…I would pull strands from my lam trimmings in the future and skip this roving…
