Are you calculating total resin usage by weighing board after process is completed? If so, having a bit more resin to start vs resin on board at completion is normal. I always allow for some to hit the floor… likely a bit of a throwback to years of using conventionally catalyzed polyester resin laminations where quite a bit is wasted but also from experience running short while wetting laps with epoxy. If glassing over dark colors, having to scrape the resin around gets it foamy (froth.) Frothy epoxy will leave ghostly overlaps for sure.
With cutlaps, a bit is also wasted on the excess that is removed after trimming. I’ve never weighed that but depending on how close to the tape you cut your cloth, it could add up.
As with MEKP polyester, you still need to allow for temperature variations in your working times. In hot weather you may have to allow for a little more waste.
What multiple did you end up using and is it based on actual ‘trimmed to fit’ cloth or by the running yard at 36" wide? There were a few ideas being tossed around. I try to allow for some variables such as those just mentioned.
When using the cheap brushes you need to tug on the bristles to get all the shedders out. I do this for 30 seconds or so. They still shed, but i only have maybe 2 or 3 come out during hotcoat…completely managable
Resinhead-My lams are still taking me more than expected, and I imagine most of it is operator error. For the deck 457 g of glass cloth I mixed about 800g of resin and figure about 707g is on the board. Some of that is ending up in puddles/drips on the cloth. Only 2 or 3 bristles to pick would be a treat. The yellow base does not hide anything. I think I’ll take a couple brushes to work and shed them out while sitting in meetings. It will be a talking point and confirm their questions about my sanity.
Johnmellor-Based on the above I would need 1.5 to 1.6 times trimmed cloth weight to coat for lams or 1.75 times to account for my lack of skills and spillage, all based on an EPS blank, 6oz cloth, and epoxy resin. My intent was to use trimmed fabric weight as the starting point so that the cutlaps and stuff would be figured in and the waste would already be figured out. I have 60" cloth (from the local composite shop, it’s either that or 30" and 60" is a better deal) so I split it down to 30" and then cut to board size. The step of weighing the trimmed cloth creates extra handling, not easy on the cloth and leads (in my case) to operator error. I think a better way would be to weight the cloth rectangles, trim to board and leave on board, weigh the scrap, and use the difference as the cloth on board weight.
I am noticing pinholes in the hotcoat more on this board. Should an EPS board be vented during lam and fill coats? I have a vented plug in the board but have not sanded it open yet.
Thats pretty funny…maybe run the brush over your face while they talk, and lick your finger and stick it in your ear & nose?
As for the pinholes? a few things. 1) make sure you do the hot coat when the temp is falling. Either later in the afternoon etc. or heat the blank up a bit, then move into shop where cooler. This way the blank will be sucking in air, and not gassing it out. 2) Also, make sure you hot coat is warm and loose. Put it in the microwave for a few seconds…like 10-15 secs, only the epoxy side…not the hardner side. if you heat up the entire mix, you will start therming almost instantainouslielously. 3) put the hot coat on thin so the bubbles can get out. i put it on with a bondo spreadder real thin, then tip out with the cheapo brush.
Scales and weighing resin is for the nervous nelly’s. After everysurfer’s commentary on the resin stuck to the container I had to laugh out loud. If what he says is true(which it’s not) why would you even consider weighing resin? Sharkcountry’s advice is good except on the initial bottom lam you potentially will get lots of strings of with the wrap. That means you have to do a cut lap with a tape off on the deck side due to sanding issues. That is time and more money spent. The deck lam can be done that way without concern because you can aggressively sand the fiberglass strands on top of the bottom lam. Epoxy resin is 50 cents an ounce. Is 4 oz too much going to break you? I would rather have too much resin than not enough. Your goal should be to be able to use fast hardener for every glass job. jrandy, you will eventually know instictively how much resin to mix up with any paticualr board by just looking at it when you get more experience. I would dump the scale and use a dixie cup. It is a more visual way to get to you understanding of how much resin to make. I have 5oz, 9 oz and 15 oz cups. You can easily cut the smaller 2 sizes to get you the desired amount of resin. The time it takes you to weigh out resin, you could be finished glassing the board with the dixie cup measuring technique. My gallon milk jug mixer and resin run off catcher minimizes waste of run off resin. pounding your chip brush against something hard makes the loose bristles fly off. Pull more off with your hand then tape aroung brush, half on metal and half on bristles to minimize bristles coming off with the filler coat and gloss coat. Use a 4" or wider brush with your gloss coat of epoxy resin. filler coat use the smaller cheaper brush. Not sure why you care about filler coat pin holes? You are going to sand and get water tight prior to gloss coat. Probably the application technique of filler coat or resin brand issue. I use surfacing agent with RR during filler and gloss coat.
I appreciate the long and detailed replies Resinhead and BB30, lots of good stuff to think about and try. I am happy with the board, just hoping to learn more faster along the way instead of the hard way afterwards.
You weigh your resin and hardener percisely. You then state that the resin stuck to the cup is just resin and not a resin and hardener mixture. Do you have a formula for that to compensate for your percise or not that it matters anymore measuring technique?
I have to call bs on that theory. I guess it is warm enough in the tropics and I know how to use a microwave effectively so scraping epoxy mixing cups is not necessary. Never had a soft cured board in 28 years of using epoxy. The only soft cured epoxy boards I have seen was at a production shop that used a scale. All the soft boards posted here are ALWAYS user error in my opinion. 2:1 mixing ratio is pretty much idiot proof, but they are building better idiots these days. Also mixing to proper total volume for the board always helps too.
I would always rather have the perfect amount or extra resin than not having enough. Not having enough leads to mistakes, Using long cure hardener is also problematic in many situations. Fast curing epoxy can eliminate many of the problems posted in this current topic.
Below is my tube dodging photo. We need to stick together!!
Hey Charlie, I’ll never forget the dixie cup method you taught us. I’m still using that first board I made at your house. I really like that board.
I always scrape the sides of the cup while mixing to make sure all the resin gets mixed up real good. By the time I pour it out most of the resin is scraped off the sides and mixed into the batch.
You’re right about the strings coming off from the glassing technique I mentioned. The guy who told me about it said to be very careful about cutting the cloth and pull the strings that hang before starting. I keep a pair of scissors around to cut the strings as much as possible, but I do cut laps for the bottom anyway. The worst part is if you’re doing 2 layers and they get a lump between them, that will mess you up.
Everysurfer is full of shat. Every left over bucket I have had of epoxy is full on hard. I still call bs on his theory. Being available for for the cut lap is essential for a quality end product.
This is not rocket science by any means. Got an 8 o’ish comming your way. Long sleves shirts and scissors solves the problem every time.
BB30, what do you mean about being available for the cut lap and the long sleeve shirts?
I have been using Kwik Kick resin the whole way through on this board, with Additive F for the non-lam coats. The product and tech support are top-notch.
I got my Probox quad set installed, first time user of the jigs and such. I don’t know an exact resin usage, guessing maybe 32g used per box with double 6oz patches in the hole and a 1/2" x 18" wrap of 6oz around the middle of each box. Poured in too much like 37g per box at first making a mess and was wishing I would have had clay in the grub holes instead of tape covers. Things turned out OK, only 2 grubs got fouled but I cleaned and greased them before the epoxy set. The numbers were something like 180g epoxy + 6 g pigment+ 4 g Add F, plenty left over per BB30’s fifty-cent suggestion. I did get a little epoxy bleed into the Super 77 holding the jigs down on the board, it this normal or preventable? How?
I also stuck some of the leftovers from another batch in the freezer to try Resinhead’s leftover resin tip.
Thanks for all the input, I really appreciate it. -J
BB30 is probably joking with the long sleeve shirts. Or it may be a reference to cutting the wet strings hanging with scissors. For the probox, you probably didn’t use enough glue or didn’t have good contact when you stuck them on. I’ll put some weight on the jigs after I stick them on and wait about 5 to 10 minutes before I start inserting the fins.
I cut out a template using cardboard to keep the spray glue from going all over. Just place it where you want the jig and spray the glue on your board, then spray the jigs and wait about 5 to 10 minutes then stick them on and put some weight on them.
I got to sand hot coats outside, a treat after the long winter. I had one weak spot on a rail that I went back after with 2 layers of 4 oz and a fill coat, each patch/coat bigger that the one before it.
The gloss coats are on. I am getting more comfortable with getting the resin poured out on the board and pushing it around without it dripping off the rails, and am OK with some left in the cup at the end.
Bottom: 313g resin+hardener and a capful of Add F. Pulled 40g off while smoothing.
Top: 362g resin+hardener and lighter on the Add F. Pulled 52g off while smoothing, cup started to exotherm. I was more aggresive microwaving this batch.
I am going to use all of these numbers as a starting point for the next board. After that one I hope to see a pattern that allows me to mix a batch for a board and end up with a reasonable amount of extra in my cup, like up to an ounce or 30 something grams.
