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Is fiberglassing rocket science?

PostPosted: Tue Aug 03, 2010 2:23 pm
by Nosty
I'd like to ask those of you who have glassed the seams on your TTT's, or the entire TTT, whether the task is as imposing as I think it is?

I'm very handy with wood and tools, but in my 50 years have never had the opportunity to work with glass. I guess I'm trying to convince myself that it isn't that bad so as not to eliminate epoxy and glass as an option for finishing my current build. As of now, I'm considering that Plas-T-Cote with the Plas-T-Cote joint tape for a final finish. From all I've read about it, it's custom made for a TTT finish, but I'm not certain that I haven't just settled on it because of my fear, (dread, actually), of trying fiberglass for the first time on such an involved and expensive project.

Any information, (or moral support), would be greatly appreciated. Normally, I live by the credo that "I ain't skeered!" This time, however, I have to don the yellow striped shirt and admit that I may just be a little skeered.

As always, thanks for all your help.

Brian :oops:

PostPosted: Tue Aug 03, 2010 2:42 pm
by Arne
flat is easy, corners are more difficult. The biggest mistake beginners make is putting too much resin on, then having to sand off the extra. I usually use a body work spatula. 1st coat holds cloth down, second fills in the weave, third gives the finished surface.

The thinner the cloth the less likely it is to lift on the corners. and the wider the piece, ditto. A narrow piece on a corner will have a mind of its own.

I'd recommend practicing.. you don't become really good at it right off the bat.

PostPosted: Tue Aug 03, 2010 2:49 pm
by afreegreek
polyester resin is pretty easy to use, epoxy is a bit more difficult especially if you want a clear finish over wood.. either way, you're better off using it on smaller project to get the hang of it before committing to a bigger project..

BTW, the glass cloth you buy will depend on whether you use epoxy or polyester.. they contain different binders.. epoxy will not dissolve the binder for polyester resin and the cloth will not go completely clear.. you need epoxy compatible cloth for epoxy

PostPosted: Tue Aug 03, 2010 3:04 pm
by Ageless
Rocket science? Hardly. I was a farm boy when i entered the Navy and after bootcamp went to Damage Control school. Part of the course was FG and after a few tries; a piece of cake!

One clue to working curves is to cut the cloth 45 degrees to the weave and even the thinnest cloth won't take a sharp corner. The cloth is 'wet out' not saturated; you want the cloth to turn clear but not be dripping wet.

If you are working in temps much over 80 degrees; the resin's pot life will be less. A trick that we used at Boeing was to chill the resin in a freezer; then when mixed, it takes much longer to kick off.

Use proper safety; gloves; respirator, ventilation; this stuff can be toxic!!

PostPosted: Tue Aug 03, 2010 3:41 pm
by NorthernMN
No, certainly not rocket science. It really isn't as difficult as you think it might be. Buy good quality resin that mixes 2:1 and slow hardner. Mix small batches so you have plenty of time to work. Work in small sections. A toothbrush works well for wetting out fabric and helps you work slowly becuase it forces you to work in a small area. 4 or 6 oz cloth 4" wide works well for seams and give you plenty of coverage while staying put.

Like anything, if you never try it you will never know.

Image

PostPosted: Tue Aug 03, 2010 4:20 pm
by starleen2
for seams and edges, I'd suggest using fiberglass tape with a selvage edge - it helps keeps the fibers together and you have less stray strings coming out of the weave at the edges.

PostPosted: Tue Aug 03, 2010 5:22 pm
by tk
Another hint is to use a pinking shears to cut glass cloth. It eliminates a lot of frustration by preventing strands from peeling out from the weave as you work the resin into the cloth.

Best,
Tom

PostPosted: Tue Aug 03, 2010 5:32 pm
by angib
If you are handy with wood and wood tools, then you owe it to yourself to learn using epoxy - you will be converted, as it is like welding in wood, or like someone invented 'liquid wood'.

There's a learning curve, but not too much, so gets few scraps and start practising.

Andrew

Re: Is fiberglassing rocket science?

PostPosted: Tue Aug 03, 2010 6:34 pm
by Larry C
Nosty wrote:I'd like to ask those of you who have glassed the seams on your TTT's, or the entire TTT, whether the task is as imposing as I think it is?

I'm very handy with wood and tools, but in my 50 years have never had the opportunity to work with glass. I guess I'm trying to convince myself that it isn't that bad so as not to eliminate epoxy and glass as an option for finishing my current build. As of now, I'm considering that Plas-T-Cote with the Plas-T-Cote joint tape for a final finish. From all I've read about it, it's custom made for a TTT finish, but I'm not certain that I haven't just settled on it because of my fear, (dread, actually), of trying fiberglass for the first time on such an involved and expensive project.

Any information, (or moral support), would be greatly appreciated. Normally, I live by the credo that "I ain't skeered!" This time, however, I have to don the yellow striped shirt and admit that I may just be a little skeered.

As always, thanks for all your help.

Brian :oops:


Brian,
Everyone is offering great ideas and encouragement, which is good! However, knowing the size of the project, especially if it's already built, I would advise against glassing your tear UNLESS you can find an experienced helper.

A beginner doing such a large project, even after practicing some, can easily get in trouble. I am not trying to scare you, just a word of caution.

If I was closer I would help you. I am sure you can find someone near you with experience to help. maybe a local boat builder or another tear builder is nearby.

We can all give instructions, tips, and our personal method of glass/epoxy layup, but an experienced teacher is worth much more.

I paid a welder friend to weld my frame because I don't weld. If you can't find local free help, I thinks it's worth paying someone with epoxy/glass experience to assist you.

In conclusion: I recommend you glass your tear, but get some experienced helpers if possible.

$.02
Larry C.

PostPosted: Tue Aug 03, 2010 8:19 pm
by glassice
I think Larry C has hit it on the head there so much crap on the web and now with Photoshop there hunders of experts that are building BS do a small item then go from there

PostPosted: Tue Aug 03, 2010 9:41 pm
by Corwin C
The first time I dove into fiberglass, I was looking at 16' of cedar strip canoe and 2 layers of 6oz cloth. Pretty intimidating to say the least. About 5 minutes in, I was wondering what the heck I'd bit into. A couple of deep breaths, roll up the sleeves (at this point they were sticky) and got down to business. It turned out well. I still get the "butterflies" before I start, but there's nothing there to be afraid of.

My advice for the beginner:
    #1. Tackle a small item first for practice. Put some glass on a 4"x6"x8" block of wood with differing radius' on each edge. See how your materials and tools work, what they will do, and what they won't. Try putting the fabric on both straight and at a bias. Everyone's situation and technique is a little different. I'm a fan of the squeegee, my brother prefers a "roller" made from alternating stainless and nylon washers. It's definitely a learned process and takes some practice to be proficient.

    #2. Give yourself plenty of time plus a little. If you're trying to hurry, you'll have problems. This process, while not especially difficult, does take quite a bit of time. Make SURE that you're working within the recommended temperatures for your resin.

    #3. Whatever resin you are using (polyurethane or epoxy), mix many small batches rather than a couple of big ones. Big batches have a tendency to set up all at once.

    #4. As you progress, look back at your work. Don't be obsessive, but in most conditions you will have quite a bit of time to "fine tune" the fiberglass. If the surface is smooth and flat, you may have too much resin. You should easily see the weave of the fiberglass. If there are fiberglass fibers that haven't gone transparent, you may need a little more resin. If you see a bubble, fix it, easy to do before things set up. (usually a press of a finger and a little more resin does the trick)

    #5. Let gravity help you whenever possible. Working flat is easy, vertical is challenging, upside down is frustrating although it is still possible.

    #6. Don't be afraid to cut the fiberglass when necessary to help it lay flat (especially on the edges.) OH! ... sin (engineers at this point are pulling out the venom keyboard). Hold on, this usage of this product can stand SOME fiber damage as we aren't really stressing it much. Also, get rid of large amounts of extra fabric. It will pull on the fabric that is part of your project and make things move AND it will soak up the resin that your project needs.

    #7. No matter how careful you are, you will ruin the clothes that you're wearing when you do this. The tools that you use (if not made specifically for re-use) will most likely be destroyed in the process. Leave your scissors wide open when you finish or they will never open again (the small amount that sets up in the hinge can usually be broke loose after it sets up.)

    #8. A little help can be priceless. I generally let Dad do the mixing while my brother and I do the actual fiberglassing. While a solo session is definitely possible, I wouldn't recommend it.

    #9. Don't walk away until your resin is no longer a liquid and completely stops flowing. Things can and will change when you're not looking. Once the resin will no longer move, you're pretty much got what you're going to get.

    #10. ALWAYS ... ALWAYS ... ALWAYS follow manufacturer's directions. Note working temperatures and pot life, times at which second/third coats are recommended, do you need to remove "blush" before re-coating? is sanding necessary before re-coating? If you are using a reputable product, the answers will be there or a phone call away. The manufacturer is very interested in your success ... use them as a resource.


Rocket science? ... No, but there is some skill involved. It is relatively easy to learn, and it is "self-teachable." Enlisting the help of experienced persons, however, would helpful for the first-timer if there's someone around that has done this before.

PostPosted: Wed Aug 04, 2010 2:52 am
by Nosty
I knew I could count on you great people for the answers I needed. As always, my many thanks for all your responses.

I'm still researching my options, but I believe I'm a little less apprehensive after hearing your opinions. I guess there's a first time for everything. Nothing ventured, nothing gained.

I'll keep you posted on my progress.

Thanks again for all your help.

Brian

PostPosted: Wed Aug 04, 2010 11:58 am
by Pizzaguy
There were 3 things I was worried about in my build.....

1. Cutting the notch in the wall panels for the hatch.

2. Building the hatch, and have everything line up.

3. Fibreglassing and Epoxying the entire thing.

#3 was the easiest of the 3.

Image

Fibreglass was not my thing... hey I'm a Pizza Guy!

Bruce

PostPosted: Wed Aug 04, 2010 12:38 pm
by Nosty
Nice job, Pizzaguy! :applause: That really came out beautifully. Just the kind of incentive I needed.

PostPosted: Wed Aug 04, 2010 12:47 pm
by glassice
Might I suggest you go to home depot and spend $20.oo buy a small kit and play with it for some it not that hard but for some.
It will take all the fear out of it
And you can see if your body reacts to it .