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You have to roughen all the gc up anyway for an overcoat, so doesn't matter.

Thanks Fallguy! I definitely wouldn’t have thought to coat the wood twice. I knew to do it once, but that makes sense, especially for the ends…I can definitely see that really sucking up the epoxy.

On another note; obviously I want to “pre cut” all the sheets of glass so I don’t have to worry about doing while the epoxy is wet. And I assume, I want to do all 4 layers of glass on the same day so I get a chemical bond across all four layers.

fallguy1000 wrote: ↑Mon Apr 17, 2023 4:58 pm You have to roughen all the gc up anyway for an overcoat, so doesn't matter.

Good point. And that brings me to some questions about gel coat. I was going to ask these further down the road, but since it got brought up, and if you don’t mind helping me out with a few questions about the gel coat??

I’ve never used gelcoat before and I know they have different types. The gel coat that I need for the epoxy resin, will that be compatible with whatever is on there now?? It’s a 1984 and 95% sure it’s factory gel coat and original. So, is there a gel coat that will be compatible with what I already have on there and what I will be putting on?

Also, does the gelcoat need any kind of primer?? I’m obviously going to need some quick fair when all the glass work is done…does the gelcoat go directly over that?? Or do I need some sort of primer between the quick fair and/or the existing gelcoat?

I have plenty of time to figure all that out, but will probably be placing another order within a month (need more glass and “maybe” 1.5 more gallons of epoxy, plus quickfair, and whatever else I need to get the gelcoat in when everything is done) and would like to know EVERYTHING else that I need to complete the project prior to that order so I only have to place one more.

I will be placing the next order from BBC again, so any tips you can offer on the gelcoat aspect of the project would be greatly appreciated!! Or if there’s a forum that discusses it, if you can point me in the right direction, I can read up on it a bit before I place my order.

Jaysen can help you better with gelcoat. I have used it zero, but I understand a wee bit about it.

Well… this is going to get controversial. I’m going to drastically oversimplify for brevity.

Gel coat is just ester (poly or vinyl) resin with dye, flow agent, thinner, and surfacing agents (misnamed “wax” but not always present) added. It is sprayed into a surfaced mold then glass is laid, plug inserted, laminating resin injected and boom… instant boat.

Mere mortals use a gun to spray gel (flow coat if wax is not added) with HVLP guns and a 2mm nozzle over large areas for repairs. Typically the repair starts with sanding addressing the underlying glass with ESTER RESIN BASED patches and fairing. We tend to be less picky with the fairing than on painted hull since we will be adding several MM or straight resin in the form of gel coat to the hull. When we have paint over gel (like on the Viking I’m currently working on) it is effectively two repairs… full gel repair then paint over the gel.

Recap— gel is ester over ester and is actually part of the final fairing even though no one will admit it.

To your question of “epoxy gel”. It’s called paint. That or you have to key the epoxy with 60gr paper, coat with straight ester resin then gel on top of that. Alternatively you can switch from epoxy to water resin for your glass work and go to gel finish.

Reality is that gel and ester are much easier to REPAIR if you’re planning to beat the crap out of a boat (like I do) but try to keep it looking perfectly finished. Paint requires less maintenance to look acceptable. If you paint use something like EMC/Quantum or AWL grip. I’m working. On an interlux hull now and it looks good, but… repair is a b1tch and longevity is less than stellar. Also has a stupid long application cycle. That would take 4hr for gel is up to 2wks as of today.

If you want more info let me know.

For the record, I think epoxy is glorious for home build. I’ve just realized the advantages of ester for commercial/pro work is all. Time is money. Epoxy takes a lot of time.

Jaysen~can he just add a layer of csm; say like 3/4 oz over the entire transom with ve and gelcoat it from there?

Jaysen wrote: ↑Tue Apr 18, 2023 8:42 am Well… this is going to get controversial. I’m going to drastically oversimplify for brevity.

Gel coat is just ester (poly or vinyl) resin with dye, flow agent, thinner, and surfacing agents (misnamed “wax” but not always present) added. It is sprayed into a surfaced mold then glass is laid, plug inserted, laminating resin injected and boom… instant boat.

Mere mortals use a gun to spray gel (flow coat if wax is not added) with HVLP guns and a 2mm nozzle over large areas for repairs. Typically the repair starts with sanding addressing the underlying glass with ESTER RESIN BASED patches and fairing. We tend to be less picky with the fairing than on painted hull since we will be adding several MM or straight resin in the form of gel coat to the hull. When we have paint over gel (like on the Viking I’m currently working on) it is effectively two repairs… full gel repair then paint over the gel.

Recap— gel is ester over ester and is actually part of the final fairing even though no one will admit it.

To your question of “epoxy gel”. It’s called paint. That or you have to key the epoxy with 60gr paper, coat with straight ester resin then gel on top of that. Alternatively you can switch from epoxy to water resin for your glass work and go to gel finish.

Reality is that gel and ester are much easier to REPAIR if you’re planning to beat the crap out of a boat (like I do) but try to keep it looking perfectly finished. Paint requires less maintenance to look acceptable. If you paint use something like EMC/Quantum or AWL grip. I’m working. On an interlux hull now and it looks good, but… repair is a b1tch and longevity is less than stellar. Also has a stupid long application cycle. That would take 4hr for gel is up to 2wks as of today.

If you want more info let me know.

For the record, I think epoxy is glorious for home build. I’ve just realized the advantages of ester for commercial/pro work is all. Time is money. Epoxy takes a lot of time.

Jaysen, that post is VERY VERY VERY informative and helpful!!!

Cheers,

Mick

fallguy1000 wrote: ↑Tue Apr 18, 2023 8:51 am Jaysen~can he just add a layer of csm; say like 3/4 oz over the entire transom with ve and gelcoat it from there?

Not really needed. The key is just getting the epoxy keyed. Esters don't like to "stick" to epoxy but they do like to stick to rough surfaces. Basically, it's just like putting epoxy ON ester. Rough it up aggressively, get a coat on to fill the keyways and start the chem bonding, then have at it.

Just remember that "no wax" is best until the last layers. Unwaxed is less fun to sand, but if you are using properly ratioed flow coat it's pretty self-leveling.

If you need guns Amazon has some that seem to work well for about $35. are they pro? no. do they leave you with a pro finish? Yep. Do you have to rip them apart to clean them like the pro-guns? yep. Does Jaysen do that? Nope. for $35 I'll run solvent through them and between coats and buy new ones for the next job. If you are doing small repairs ... look into Preval sprayers. I'll never use a roller again.

Anyway...

Jaysen wrote: ↑Tue Apr 18, 2023 11:10 am

fallguy1000 wrote: ↑Tue Apr 18, 2023 8:51 am Jaysen~can he just add a layer of csm; say like 3/4 oz over the entire transom with ve and gelcoat it from there?

Not really needed. The key is just getting the epoxy keyed. Esters don't like to "stick" to epoxy but they do like to stick to rough surfaces. Basically, it's just like putting epoxy ON ester. Rough it up aggressively, get a coat on to fill the keyways and start the chem bonding, then have at it.

Just remember that "no wax" is best until the last layers. Unwaxed is less fun to sand, but if you are using properly ratioed flow coat it's pretty self-leveling.

If you need guns Amazon has some that seem to work well for about $35. are they pro? no. do they leave you with a pro finish? Yep. Do you have to rip them apart to clean them like the pro-guns? yep. Does Jaysen do that? Nope. for $35 I'll run solvent through them and between coats and buy new ones for the next job. If you are doing small repairs ... look into Preval sprayers. I'll never use a roller again.

Anyway...

Thanks Jaysen!!

So, if I’m understanding you correctly, I just do all my repair, glasswork, fairing work until I’m happy with that. Then, sand some good gouges into everything that I will be gel coating. Then I can just use the “Non-wax” gel coat that BBC sells and spray that right onto everything, then add wax for the final layer. Correct?? And just pick up a cheap spray gun from Amazon and chuck it when done? I don’t plan on doing any gel coat work after this, so I’m perfectly fine with a “disposable” $35 gun.

I really appreciate the input!! I was actually really concerned about the gelcoat process and didn’t even want to think about it until I was closer to doing it. But that makes it seem a lot less intimidating.

Side note; I read somewhere to only gelcoat when temps are 70 degrees and above to ensure it hardens. But the hotter the temps, the shorter the pot life. Does that sound correct?

Recall that I started off with

Jaysen wrote: ↑Tue Apr 18, 2023 8:42 am Well… this is going to get controversial. I’m going to drastically oversimplify for brevity.

This isn't as simple as it sounds but is simpler than it feels once you start doing it. I'm assuming you are doing bare glass to standard 2.5-3.5mm solid color over about 20sqft. Let's start with a few supplies that you need:
* Acetone - Get a couple gallons.
* Styrene - Get a gallon. You might use 2 but start with one.
* raw resin - 2 qt.
* Gel - Couple gallons. Base color depends on end color.
* MEKP - NOT MEK. MEKP. Order about 1.5x the amount you need for the amount of gel you order
* Wax - 4 oz.
* Dye - hahahahahahaha. Yeah.
* Paint guns - I use these. Buy 3. You will kill 2 fast unless you know how to manage gel.
* Air compressor - with the above guns I use a porter cable pancake. I mix small batches. go slow.
* Clear dixie cups for mixing
* Mix sticks from Walmart.
* A face shield because that stuff will get on your face.
* Clothes you want to have match your boat.
* Wet paper from 220 to 600. You don't need more than that.

FlounderPounder wrote: ↑Tue Apr 18, 2023 12:12 pm So, if I’m understanding you correctly, I just do all my repair, glasswork, fairing work until I’m happy with that.

Yeah. Problem with fairing is that when you hit it with the 60gr you really think it will still be fair? If possible finish up with the epoxy and switch over to ester for fairing. You can just use automotive bondo (the orange kind). Sands super easy and is ready for sanding in about 15 minutes.

FlounderPounder wrote: ↑Tue Apr 18, 2023 12:12 pm Then, sand some good gouges into everything that I will be gel coating.

If you do fair with epoxy be SUPER light on your epoxy fairing. Consider hand sading that area with 36gr and RO the rest with 60. last thing you want is to take a good fair job and mess it up. That said... gel is just fairing compound without filler. Just lay it thick

If you don't like the above, don't ever cut a production boat across the keel.

FlounderPounder wrote: ↑Tue Apr 18, 2023 12:12 pm Then I can just use the “Non-wax” gel coat that BBC sells and spray that right onto everything, then add wax for the final layer. Correct??

Eh... kind of maybe but...

It would be smarter to spray thinned resin, first. Do I do this for all repairs? No. But I'm not going over epoxy. The point is to give the gel a base that is somewhat uniform and allow it to flow (remember it is kind of self-leveling) evenly. The method to "spray a coat" is pretty much the same no matter if you are spraying resing or flow/gel.
1. guess about your MEKP ratio (the science is black magic mixed with voodoo mixed with science)
2. Measure out about 7oz of resin/gel into a dixie (should be pre-dyed)
3. Add MEKP with adjustment for desired behavior modification.
4. mix mix mix for about 30secs
4a. add wax if this is the last layer... mix mix mix for 60secs
5. Add styrene till just about like water.
6. Pour into gun cup.
7. Spray a light coat. DO NOT TRY TO PAINT IT. They call it flow coat for a reason!

FlounderPounder wrote: ↑Tue Apr 18, 2023 12:12 pm And just pick up a cheap spray gun from Amazon and chuck it when done?

Eh no.

8. you've run out of material in the can. STOP.
9. put in about 2 ounces of styrene and swirl it around in the cup to loosen up the resin/gel
10. spray that through the gun
11. dump 7oz of acetone into the gun and spray it into a catch can (it will settle and you can reuse it).
12. repeat 11
13. repeat 11
14. (that should be 5 rounds of 7oz of acetone through the gun) set gun down
15. go make next batch of gel
16. grab new gun and spray gel

if you really know you have 11-13 done right you can reuse the same gun. if you don't get it right you will know you have a problem the second you go to spray. If you have. a problem with a gun, that gun should be salvageable but you can't dally... load the second or third gun to use the gel, and then clean both. You will need to disassemble the clogged gun to clean it fully. If you put to much MEKP in or have it set for fast kick then you toss the gun. After about 5 uses the acetone will start to eat the seals. That's when you toss them.

FlounderPounder wrote: ↑Tue Apr 18, 2023 12:12 pm I don’t plan on doing any gel coat work after this, so I’m perfectly fine with a “disposable” $35 gun.

You can do it with one gun. I use three. I'm making $ though. Time is money.

On the temp...

I'll apply with no external heat source at 65. I'll upp the MEKP about 5 extra drops for every 10 (that will make sense once you do this a bit). That is to get sandable in 60min. Recoat 20mi. under 65, put the resin/mekp in a cooler with a heating pad and use HALOGEN lamps to heat the surface for about an hour before hand. use IR thermometer to make sure the surface gets to that 65. If temps get over 75 (which I already have) I pull the MEKP back a bit. Reduces the risk of fire and prevents cracking due to shrinkage. Still keeps me in the 60/20 times.

I recommend you grab some ply, through glass over it and run a few tests to see how it goes. It was a PITA for me the first couple times. Once I figured it out it's been almost relaxing. Almost. Once I can eliminate sanding it might actually be relaxing.