First off I want to say how much I really appreciate all of you guys sharing your wealth or knowledge and experience in this forum. I have been learning the art of hand shaping for a short while now, and have learned so much from all of you, so thank you!
Recently I decided to install black futures box rather than the normal white. I found that when sanding down the boxes prior to hot coating, a fair bit of the black dust from the box was getting into the small pockets in the cloth. Blowing it out and off with air was only partly successful. Anyone else experience this, and/or have solutions to improve this?
If black dust is getting down in the cavities of the glass, your lamination is too dry.
Leave more resin.
You could fully Hot Coat the fin area, then grind down boxes and sand entire fin area before fully Hot Coating the bottom.
I’ve done that when pasteing the laps for sanding.
Shop Vac + round brush nozzle
But I usually grind off the resin dam and tape after hot coat, so black flecks in the lam would not be an issue
If you fiberglass patch boxes prior to bottom lamination you have two layers of fiber glass to work with. I always second coat filler or in your case “hot coat” then sand, fix any screw ups and final coat or gloss coat the lamination.
spray tac patches on boxes
bottom lam with filler coat or your “hot coat”
Deck lap to bottom with filler coat. Preparing to router off raised box and not sand
result of router
Sand perfectly flat to deck
Final coat or your “gloss coat”
Guess I’m missing something. Why would you grind your boxes before the hot-coat. And If you have done a decent hotcoat there shouldn’t be any open weave at the fins. Grind the fin boxes flush, gind the leash plug and begin sanding the entire board… When I say grind the fin box, I’m not saying grind so severely around the box that you exspose weave. Grind the box flush, then sand the board.
If your basting the lap from the deck lamination for sanding/flattening which i think is a good technique then its not too much trouble to brush a little extra resin around plugs and sand flat before hotcoating full board for sand. It also allows you to get any tiny bubbles out before the final coat if you get any.
Thanks for the imput guys! Much appreciated!! I think I should be able to improve things with those pieces of advice. And @McDing, yes I am grinding down the box before hot coat as suggested by Futures (https://vimeo.com/93304896) Would you suggest not?
I’ll take a look at that video but; I’ve never heard of grinding before the hot coat. And Yes: If you grind black or even white boxes on a tacky exsposed lam, you will get black flecks everywhere. And they’ll be a bitch to get out of the weave(even with an air nozzel) because of the tackiness of the lam resin and the open weave. I have never seen or heard of any Pro glass shop grind boxes after the lam and before the hotcoat. Just a recipe for problems. I mean think about it for a minute; Why would you even need to do that? What’s the purpose?? Lowel
Ya, I hear you. Have a look at the video and let me know your thoughts. I ll try your suggestion. Thanks.
Checked out the vimeo. That’s doable with white boxes. But I wouldn’t grind black or colored boxes on a tacky lam. I really don’t see the reasoning for grinding before a hotcoat. A good hot coater can lay on a coat of resin around any obstacle, like center boxes, plugs etc. I guess I’m just too production oriented to add un-needed steps. Also if you do as most glass shops do and grind the laps, boxes, plug etc right there in the lam room; you are running the risk of contaminating other in progress boards on adjacent racks with little black flecks. I just don’t see the necessity and I sure don’t understand why they would reccomend it. Grinding lam resin is tricky business to begin with. One little overgrind and you’ll have to do a patch on a burn-thru or worse yet ; lam resin dis-colors and turns brownish if over heated while sanding or grinding. Lowel
I actually attempted this Once many years ago by grinding a black center box before the hot-coat. I complained about it to a local glass shop and his reply to me was that his shop only used white boxes as a precaution. Never again.-------- I would say that if you are going to use this method, baste around the boxes with sanding resin before you grind. Take my advise with a grain of salt. Obviously some people are doing it this way so----Just baste around the boxes to fill the weave. L
not being in the production biz, I have only sanded, then taped and hot coated. I would agree with the statement your lam coats may be too dry. I have done multiple black boxes, and I haven’t had the dust issues you mention. Now, CF rails on the other hand… Anyway, if you don’t do subsequent steps immediately in succession, much like a person that pines to actually get spare time to work on a board in the garage, you may even find yourself scrubbing the board with a degreaser between coats to ensure good adhesion and avoid blush issues with epoxies. Just a suggestion.
Absolutely unrelated. You just used one of my favorite words.
Example: “He’s pining for the fjords . . . Beautiful plumage.”