The Tao of Fiberglass Repair

[Seadogg]

So, I've been getting prepared to do some work on First Step and to remove some thruhulls the previous owners had installed, which I don't need.

The fewer holes in your boat, the better.  Right?

Of course, Michigan is experiencing very high temps right now.  Epoxy cure time will probably be on the order of 2.5 seconds.   ;)

Saturday morning, it didn't feel too bad out and I began the work of removing the first thru-hull.  I picked the one on the bottom of the boat (transducer?) figuring it would be best to get the roughest one out of the way first.

Now, I've been a bit nervous about this.  In my mind, I've been thinking that the PO probably did something funky and I would wind up with

a. a thruhull that had been glassed in or
b. had 5200 lathered all over it

and therefore

c. I'd wind up NOT being able to remove and having
d. a cracked/messed up bit of marine hardware that
e. would prevent the boat from ever being water-tight again!

Ah, the things our imaginations like to do to us...

Well, I grabbed the channel locks and in less than five minutes, had the thru-hull removed with no cracking, smashing, or cussing.  Pretty sweet!

I then began the process of dewaxing and cleaning up.  It was at this point that I noticed that I'm gonna have to be a little creative.

The hull is 1/2" thick at this point, not 1/4" thick like I had previously thought.  Therefore, the 12-1 bevel SHOULD be around 6" from the hole.  The problemis, the hole is only 2 1/2" away from the keel trunk.  Hmmm....

So, I have decided that I will bevel the outside in a warped oval shape.  6" where I can and 2 1/2" where I have to.  On the inside, I will bevel down and up the inside of the keel trunk.  This way, what I can't properly do on the outside, I should be able to get closer on the inside.

I hope it works. I don't see why it shouldn't.

However, about the time I made the decision to go this route, the temps had begun their climb and it was getting a bit uncomfortable.  I just couldn't picture myself putting on long sleeves, a coverall, a head piece, goggles, respirator, and then crawling under the boat to grind away fiberglass.  Having not done this before, I have no idea how long it would take.

Sooo.... as soon as the temps cool down a little bit (under 99 would be nice), I'll actually be able to get some work done.

I'll post pics and keep you informed.

Fair winds,

Nick

[Zen]

You may need to start early in the morning to get that done. Going by the global warming show I saw last night, it will geting hotter sooner and longer these days.
or
Install a cooling unit in your protection suit.  :)

[AdriftAtSea]

Assuming that you're using epoxy resin, the one thing you do  have to watch out for is condensation on the working area, especially if you're working late into the evening.  Condensation can cause the epoxy problems with curing properly in some cases.  Also, don't forget to rinse the epoxy to get rid of the amine blush if you are going to continue on an area started the previous day.  :D 

[Seadogg]

Schedule clear?--Check!
All tools and materials ready?--Check!
Consulted and re-consulted with the local fiberglass experts here?--Check!
Weather under 100 degrees?--Check!

Tomorrow morning, after my morning coffee and crossword with my beautiful wife, I will begin the grinding and reglassing process.

No, really.  I mean it. :D

I'll definitely get the bottom thruhull hole reglassed.  Maybe the other two.  All depends on how the first one goes and if I can get to them.  I'm hoping I get inspired!!

Again, thank you, thankyou, thankyou, to everyone for their help.

Pictures to be posted.

Nick

[s/v Faith]

You can do it Nick!

  IMHO, you may want to prep the other ones because once you see just how easy it is you are gonna go ahead and do them all.

  The prep is really the hard part.

Also, cut as many 'patches' as you think you are gonna need, and then cut a couple 'extras' just in case.  You may drop one that has epoxy on it, and the dirt and grass it will be covered with won't make the repair any stronger...  ;D  So if you plan to patch 3 layers from the outside, then cut a couple pieces that are in between the sizes. It is hard to operate sicsiors with epoxy covered rubber gloves on. 

  When you are done, you will be suprised how easy it was.

[Zen]

May the epoxy be with you...

Be one with the fiberglass. ( but not literally )

;D

[Seadogg]

Thanks, Zen!

Hope you and Lady Z have a great  weekend .

Nick

[AdriftAtSea]

Besides, once you've got the tyvek bunny suit on, the idea of not doing all three at once is kind of silly.  Try not to get epoxy on yourself, or anywhere else you don't want it.... Don't forget to wear a good respirator to capture the styrene fumes, which are pretty nasty, and the fiberglass particles, which are also nasty.

[Captain Smollett]

If you DO get resin on the skin, Glen-L sells a cleaner that takes it off really good and has skin conditioners and the like in it.  It is realy good stuff.  As I understand it, any waterless hand cleaner (from auto parts stores for example) will do nicely as well.

Even still, it wears off in a few days and aside from being sticky while it cures or ugly, no real harm done.

[CharlieJ]

I keep a pump type container of GoJo Natural Orange in my shop always. Works well for removing epoxy.

Vinegar is also a useful solvent for uncured epoxy- cleans tools quite well, although I commonly use lacquer thinner for tools. Either white or regular vinegar will do.

Acetone sometimes reacts with epoxies, so I try to not use that, although it's a good solvent.

[Zen]

Acetone sometimes reacts with epoxies, so I try to not use that, although it's a good solvent.

It also does not react well with your lungs  :o

[Captain Smollett]

It also does not react well with your lungs  :o

Huh?  Acetone is not "bad" for you, especially in a well ventilated area.  We used to use acetone (indoors) by the 55 gal drum.  Having been a chemist for 25 years or so, I've used a LOT of acetone in my career.

You treat it like any other solvent, but other than that, it's not bad.  (Ie, no huffing   ;D  ).

Gasoline is FAR FAR FAR FAR worse to breathe, and you probaby inhale a LOT more gasoline at the pump filling up your car than you do acetone working outside prepping or cleaning up a glass project.

Sorry, I don't mean to sound preachy, but I've seen these references to acetone on other forums like it is some kind of WAY dangerous, don't-handle-it-at-all toxic chemical...and that is bunk.  I'm not saying YOU said that, Zen.  I just wanted to 'set the record straight.'

[AdriftAtSea]

Just be careful with Acetone.  IIRC it is skin absorbtive...and not so good for your internal organs IMHO. 

Vinegar is probably the safest of the ways to clean off uncured epoxy.  One warning about having uncure epoxy sit on your skin—it can eventually cause you to become allergic to epoxy, and that is something you probably want to avoid. 

[Paul]

Captain Smollett:
What say you about MEK and Tolulene?  These are also used in prep for repair work.  Any chemical consultations are appreciated. ;)

[Captain Smollett]

Just be careful with Acetone.  IIRC it is skin absorbtive...and not so good for your internal organs IMHO. 

Not true.  Acetone is not absorbed throught the skin.  In labs, we often wash glassware with it before washing with detergent.  It does, however, dissolve (and therefore remove) the protective oils from your skin - it will dry your skin out.  So, you want to limit direct exposure.  Actually, I use acetone for washing some things off my hands, then wash with soap and water.  Some slight direct exposure will cause no acute or chronic health effects.  Period.

It's only not good for you if you DRINK it or breathe LOTS vapors.  It is also flammable.  There are, however, a LOT of 'rumors' about how dangerous acetone is floating around. 

If you practice ordinary shop safety with it, it is a relatively save solvent to handle.  Like I said, the hydrocarbons (gasoline, diesel, mineral spirits, etc) are worse to handle.  If you handle mineral spirits in your shop, or fill your car/boat up with gasoline yourself, you have nothing whatsoever to worry about handling acetone.

What say you about MEK and Tolulene?  These are also used in prep for repair work.

MEK is methyl ethyl ketone, whereas acetone is methyl methyl ketone.  They are VERY similar to each other is all respects.  In one plant I worked in in Charlotte, NC, we used MEK by the tanker load -- that's train tanker.  Handle with care, proper ventilation, the usual precautions.

Toluene is similar to benzene, and both are key components of gasoline (see earlier comments about handling gasoline).  They fall into the aromatic hydrocarbon class of chemicals (aromatic means a specific chemical property, not really related to odor) and are known carcinogens (cancer causers).  The total aromatic content of gasoline (there's a bunch of 'em in there) is limited to 35% in California, for example, and we are all aware of all the danger warning labels about breathing gasoline vapors.  I'd be more weary of handling toluene and benzene than acetone or MEK, but again, with proper ventilation you can do it.

The key with all of these is, again, proper ventilation.  That's outside as a first choice, a WIDE OPEN shop (with fans) as a second.  No closed shops.  An air conditioner is not 'ventilation,' so a closed up air conditioned shop is not, in itself, properly ventilated.  You CAN choose to wear a respirator with VOC filter if you want extra protection (really, outside, you should not need it).

Tha's my two cents, and I've been a chemist for 25 years (BS and PhD), I've taught chemistry at three universities and one college and have owned my own chemical consulting business for six years.  I've also been a volunteer firefighter and ran a forensic chemistry laboratory and testified as an expert chemist in State and Federal Courts.  Finally, I worked in a lab handling some of the most toxic substances known to man (the EPA Hazardous Materials Reference Bank Extreme Hazard Laboratory located in Research Triangle Park, NC in the late 80's). 

Believe me, there's FAR worse stuff than over-the-counter shop solvents.  If they sell it at the hardware store, it AIN'T that dangerous.

[CharlieJ]

Now MEKP, that's another animal. THAT'S the catylst ( methyl ethyl ketone PEROXIDE) in polyester resin and IT ain't good for you.  ;D ;D

Thanks for an authoritive write up on Acetone and other solvents, sir.

[Captain Smollett]

Now MEKP, that's another animal. THAT'S the catylst ( methyl ethyl ketone PEROXIDE) in polyester resin and IT ain't good for you.  ;D ;D

Yepper, peroxides are a lot of 'fun.'   Some are highly explosive.  Ethers can form peroxides just sitting around in the bottle, and they are sometimes friction sensitive.  In other words, the peroxide crystals form on the ether bottle cap and threads, and when you try to unscrew the cap ....


BOOOOM   :o :o

A chemist friend of mine once had a job designing 'more powerful' chemical explosives.  It was with peroxides he was working.

[Seadogg]

Well, saturday came and went without an opportunity to work on the boat.

But Sunday, I managed to a little bit done.

First, I'll show you what was there.


This thru hull was on the bottom of the boat right next to the swing keel.  I'm thinking it was originally used for a transducer.  Instead of removing it and reglassing the hole, the previous owner decided to attach a hose and use caulk to seal it.


Pop!  She's outta there!!


Exterior view.  Not much room between the hole and the keel.


I ground out six inches from the hole EXCEPT the keel side.  That one was only 2 inches. on the inside, I ground up the side of the keel trunk and laid down 4 layers of glass.


After creating the patch on a piece of plastic sheeting, I transferred it over to the hull and smoothed it on.  Then I duct taped it up. "Poor man's vacuum bagging".


Interior view of the glass/epoxy patch.  Tomorrow I'll know how well I did.  Then, I'll sand it, fair it, sand again, and paint.

Whew!  What a job.  However, this was the hardest one and, now that it's out of the way, I'm looking forward to doing the ones that are easier to get to.

I'll let you know what transpires.....

Nick

[Captain Smollett]

Good job, Nick. That sure likes like a wicked awkward place to do such work.

[Seadogg]

You're not kidding!!!

When I was grinding, I was in such a weird position that it was hard to even see what I was doing.

After I got the patch in place and smoothed it out, my arms were so tired I had a heck of a time just pulling the tape off the roll!

After I got done, I crawled out from under the boat, tossed my clothes off and fell into the pool.  Ahhh....

Think I did pretty well, though.  And only had a small itchy patch on my wrist area from the fiberglass dust.  :D