Fiberglass Creases, Wrinkles, Bubbles, oh my!

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themrbruceguy
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Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by themrbruceguy »

Hey there. I fiberglassed my first canoe 9 days ago, so I think the epoxy is pretty well set to begin scraping/sanding. I used West Systems 105/207. The day of fiberglassing was ~97F, which made time between coats fairly short. About 1.5-2.0 hours. We didn't use a seal coat. We performed 1 wet-out coat with 3 fill coats after that. The wet-out coat was performed using squeegees. All fill coats were applied with a 3mm foam roller. The second and third fill coats were tipped off with a brush running parallel with the direction of the strips to address the tiny bubbles from foam rolling. However, I did not think to do this on my first fill coat, which left some tiny bubbles behind (talked about in issue #5 below). Overall, I am pretty happy with how it all turned out, given that this is my first time using epoxy and fiberglass. From what I've read on this forum, I think most of my issues can be addressed. But I do have some questions that I couldn't find answers to when searching the forums, or would like a greater clarification on. I asked questions in order from my highest amount of concern to my least amount of concern.

1.) Fiberglass creases / wrinkles
- While we were approaching the middle of the canoe, it became fairly difficult to keep the creases at bay and we were eventually forced to deal with them. We did the best we could, but it was obvious these creases were going to show up after the epoxy cured. After the epoxy cured, the creases were even worse than they were during the wet-out application. I guess the cloth shifted slightly while curing, forming a taller crease.
Q1.) How could we have avoided these creases altogether?
Q2.) I have read that it is best to use a carbide scraper (I just ordered this one https://www.amazon.com/gp/product/B0002 ... PDKIKX0DER from Amazon) to take down the high spots prior to sanding. I am fairly certain that I am going to expose some fiberglass on the taller creases, which I have read will require a patch, then epoxy, then feathering to the rest of the hull. Could someone help explain the patching / feathering process? Pictures would be awesome if possible.

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2.) Visible fiberglass weave
- I believe this was due to my friend (who was working this side of the canoe during our wet-out coat) trying to use epoxy that had sat in the cup too long and was starting to become thick, and thus, was unable to fully penetrate the glass. We didn't notice this mistake until all fill coats were applied.
Q3.) Is this a structural issue that needs addressed, or is it simply a cosmetic annoyance?

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3.) Small bubbles trapped near hull/outer stem interface
- Again, we tried our best getting the epoxy to fill this space, but we ended up getting a couple areas with small bubbles where the hull meets the outer stem.
Q4.) What is the best way to address these little holes?

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4.) Exposed fiberglass on the outside of outer stem
- There seems to be some fiberglass that didn't get bonded well to the ash outer stem surface. This may have been my mistake by not cutting the fiberglass far enough up the length of the stem though.
Q5.) Should I have cut the fiberglass all of the way up the length of the outer stem?
Q6.) How should I address this area shown in the photo below?

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5.) Tiny bubbles throughout hull
- I believe these tiny bubbles came from my first fill coat. This was the only fill coat where I did not use a brush to tip off the bubbles that formed. I used a brush on fill coat #2 and fill coat #3 which really seemed to help keep bubbles at bay, but I still had the tiny bubbles from fill coat #1.
Q7.) Are these best addressed using the carbide scraper as well, followed by standard sanding procedures? Or would you guys just go straight to sanding these?

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6.) Raised spot of fiberglass
- This raised spot is not very big in area, but it stands very proud of the hull. Like a tiny mountain. Using a carbide scraper will almost surely expose fiberglass when knocking the high spot down. The first picture shows the raised spot from the front, and the second picture shows the height of the raised spot.
Q8.) Is repairing this area going to be similar to repairing the creases / wrinkles? -> Scrape, fiberglass patch, epoxy, feather, etc?

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Thanks for reading! I apologize for the long thread. But I wanted to make sure everything was communicated clearly with photos in order to solicit the best feedback possible :)

~ Jake
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by Cruiser »

Hi Jake ... that's a lot of questions

1) 2 ways that creases get there, one is you do it by pushing the FG around to hard, second is the glass was creased from supplier .... so if it's creased when you lay it out .. it will be creased when you wet it out. If you pushed too hard or mismanaged the FG when you did the epoxy, that is a different answer ... look here fr how to handle the glass, hopefully you will find where you went off track ..... https://www.youtube.com/watch?v=suefRmBfrwg

I would stick with rollers personally, but the purpose of the video reference is to learn how to handle the cloth

2) The creases you are showing are high on the side, very load area, unless the exposed area is wider than 1/4" or so, i would be tempted to just level and move on. The carbide scraper is the best way to handle the high spots IMO, go slowly, don't try and remove too much at a time, it will level pretty quickly. In the future, the scraping is best done the next day while the epoxy is still green, just makes it a bit easier.

Feathering process, I did an explanation on my last build here for the bow/stern "extra" strips I use, but the process is transferable generally ....https://www.canoetripping.net/forums/fo ... uild/page8

3) you really can't do much about that now, the strength is almost exclusively in the first coat of epoxy, the rest are for cosmetics, so I do what i could to smooth things out and maybe make a list of things not to do next time ... sounds silly, but you will be amazed how useful notes like that can be

4) make a note to check for those next time, you can't walk away after the first coat, you need to walk around the boat and look for bubbles and runs for the first 30 minutes or so ... saves a lot of "oh shit" moments. I personally would just forget about those bubbles ... they won't impact anything but your sensibilities

5) not all the way, just far enough that it sits smoothly on the wood, good news is that you can just sand off anything that doesn't fit right ... and I posted the link on feathering and adding extra abrasion strips to that area

6) SEE 5)

7) I never recommend sanding epoxy high spots, always scrape level, go round the whole boat and level all the areas you can find that are obviously high. When you get frustrated doing that, you learn that getting the right amount of epoxy on is something you really need to dial in, or you end up with the crappy job of leveling the whole thing. You would be better being a little too light than too heavy on the fill coats, plus make sure you review the goals of each coat. Ted talks about those in the first link

8) Personally, I would level that and move on .... any area you scrape back to cloth or wood should be resealed with epoxy, but you can go over the whole boat and get them all at once. If the exposed area is less than 1/4"-3/8" and is in a noncritical area, just clean it up, seal it and move on IMO

It looks like you did most of the right things, have read enough to figure what needs to be done to fix them and are taking critical stock of the results, so good on you.

I don't see anything there that is going to require anything major to fix and most of the creases won't likely need patching/feathering ... but it your build ... you get to make the call. That build I linked is a complete build, you make pickup a few points that are useful to you moving forward, also the CanoeCraft series on Youtube has a lot of great info on the building steps, always a good place to start each step.

Brian
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themrbruceguy
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by themrbruceguy »

Brian, thank you so much for all of your feedback! I appreciate it very much!

I received my scraper in the mail yesterday and have put it to use. I'm very pleased with how well it works leveling out the high spots! Lucky for me, I haven't exposed any fiberglass yet (which really surprised me), but the task is not totally finished, so we will see how that turns out. Below is a photo of the worst / highest runs on my canoe which are now totally leveled out.

Image

I will try and remember to upload a picture of this same spot once the canoe is 100% done and varnished just to provide a before and after of the runs / creases.

Thanks again Brian!

~ Jake
sedges
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by sedges »

Seems like you are well on your way to getting past the wrinkles and roughness of your glassing job. My first boat was just as interesting, but in different ways.

For future reference. I think two issues may have caused this.

One, 97 degrees is just too hot to be applying resin to cloth. It shortens your working time so that you are trying to push epoxy into the weave, by any method, when the resin is starting to thicken. Air does not escape easily and gets trapped under the cloth, the cloth gets pushed around and distorted.

Two, before you start applying resin, cut off the fabric a couple inches beyond the hull. This allows the fabric the move and stretch a bit better because the selvedge( the bound edge of the fabric) is gone. After you drape the cloth on the boat and trim it, smooth it around with a big clean paint brush or bench brush. It gets the fabric to stretch a little to form to the hull. I even do that a day ahead and let gravity work on it, too.

I think that will take care of your wrinkles. Good luck with the rest of your build!
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by Cruiser »

As Sedges points out ...higher temp will shorten your working time, you can mitigate this quite a bit by getting the epoxy on the boat faster, once it is spread out, the heat can escape easier ... but getting it spread fast is key. I think an issue ppl have is trying to make it look good, as if you were varnishing ... just get it spread to start soaking, you will be taking most of it off when you squeegee, so neatness at this point is useless and takes time.

Watching that video is also key on learning "where" to put the epoxy as you go, being able to "adjust" the cloth as Ted demonstrates will save you a lot of issues in the future.



Brian
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themrbruceguy
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by themrbruceguy »

Thank you for the responses, sedges and Brian!

One more question related to this topic: I currently do not have any fiberglass protecting the edges of the bow and stern stems. Is it okay to basically seal this exposed section with several coats of epoxy, or would it be more wise for me to wrap a piece of fiberglass around the stem, epoxy, and feather it into the existing hull?

Thanks,
~ Jake
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by Cruiser »

It is not "essential", but I would strongly advice at least 1 strip on the bow/stern. Personally I do 2, you can see the technique in the link I made to my last build.

If you decide to do this, the key point is to cut the cloth on a 45 degree bias as is stated.

Brian
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themrbruceguy
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by themrbruceguy »

I have read your write-up on installing fiberglass strips multiple times, it is very thorough and helpful! However, I mistakenly have already sanded my entire hull (80 grit, 120 grit, then 220 wet sand) which took a long time. I was very careful and thorough in these sanding stages, so I'm pretty proud of the results.

1.) If I do decide to install fiberglass strips over the stems, is there any risk of messing up the sanding job that I have already performed on the hull? I will be careful to tape off the surrounding area just like you did. I guess I'm most concerned about feathering the new epoxy into the already-sanded epoxy, which could result in oversanding the already-sanded section, and possibly expose some fiberglass weave.

2.) I'm pretty convinced that I still want to install the stem strips per your write up. Will this adhere okay to 220 grit wet sanded epoxy?

3.) I am concerned about not having enough fiberglass left to glass the inside if I start cutting these 45 degree strips from my remaining roll. Do you know of online sources where I can buy extra 6oz fiberglass on a roll? Also, would any online suppliers happen to sell it in a 45 degree orientation on the roll instead of 90 degrees? This would result in less waste for us builders, but would most likely transfer that waste to the manufacturer, so who knows... haha

~ Jake
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by Jim Dodd »

#1 Yeah it will look ugly,, until you varnish. but sand the area where the bias strips will go. Apply wide one first. the next one right on top, right away.
You can try Peel Ply, or Saran wrap,to compress the cloth, but not necessary. Let it cure over night and the next day apply 3 fill coats. Wait another day, with a rounded scraper, or an old pocket knife, "Feather" the edges of the bias strips. A little hand sanding, a week later to give the epoxy time to cure ! You are ready for varnish.

#2 Yes.

#3 Lay your cloth out on the clean dust free hull. and see if you have enough cloth.

Didn't you have trimmings left from glassing the outside ? I make my widest bias strips about 5" wide, and the narrow one about 3".

Image

Image

Jim
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by Cruiser »

Like Jim said and ....


Just a note of the sanding, going to all the trouble of a 220 wet sand for final, is overkill iMO ... you still have to get to varnishing and for that 220-320 is the recommended sanding ( I use 220 on first coat, then move 320 for the rest).

If you sand into the weave, you can just retouch an area with epoxy or as I do sometimes, just add another thin epoxy coat. Since you have already sanded and fared, you only need to use 220 on this thin coat ... so it is relatively little work.

Just remember, it's also a good idea to wash the epoxy coat with warm water and a few drops of detergent, before you start sanding .... let it dry and have at it.

You won't mess up the hull or the sanding job, you feather in new stuff, sand and it disappears, don't worry about being able to "see" where the layers are, there is an optical component here, the areas where the glass ends are sheered turn white and so you see them. Once they are recoat, they go back to clear and disappear.

Have at it you doing the right stuff.


Brian
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by Jim Dodd »

I find no need to recoat with epoxy.

I simply varnish over the sanded bias strips ! Even though the weave is visible, after sanding. the Varnish hides it.

Jim
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by Cruiser »

The bias strip can be sealed with a thin coat of epoxy or just varnished over, It is a matter of builder preference. I like to have a complete epoxy seal after I feather fiberglass, but it is a little more work.

It's like doing glue ups with wood, some folks just coat one side, clamp and that can work, I like to coat both sides, clamp and feel better knowing there is no chance of there being a dry spot inside.

Know that either way will work, you have decide whether you are a "one side" or two side" builder.

Keep making dust.

Brian
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Jim Dodd
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by Jim Dodd »

Yeah ! I've been gluing up cutting boards lately, and like you. Butter both sides of a joint.

There is plenty of glue dripping, but no Voids. I have my share of OCD !

Jim
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themrbruceguy
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by themrbruceguy »

Jim Dodd wrote: Wed Aug 05, 2020 10:06 pm Didn't you have trimmings left from glassing the outside ? I make my widest bias strips about 5" wide, and the narrow one about 3".
Hey Jim. Yes, I do have some trimming left from glassing the outside. However, Brian mentioned in his link that the strips must be made with 45 degree orientated fiberglass. He creates those 45 degree strips by cutting on a diagonal from his main fiberglass roll. I'm sure this works great when you have a lot of fiberglass to work with, but I am certain that I would not have enough fiberglass for the inside of my canoe if I cut strips like that.

So I guess the main question is this: are the 45 degree orientated strips a "must-have", or will plain 'ole 90 degree scraps work just fine for the job?

Thanks,
~ Jake
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Re: Fiberglass Creases, Wrinkles, Bubbles, oh my!

Post by Jim Dodd »

It's not critical to have it be a 45* ! If you get even a little bias angle, it will work . It's mostly to make the cloth lay better.
Wet cloth can be "Massaged" to lay flat. You just work it a little more.

Jim
Keep your paddle wet and your seat dry!
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