Glassing, the John Coker way

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Kehoes23

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I just recently started to fiberglass my body tubes, the way that I have been doing it was put the tube on a pole between two chairs, wet out the tube and roll on the glass with a brush, I thought this method was too time consuming and tiresome and not very good results, then it ran across John Coker's way of fiberglassing on YouTube, so I decided to try John's way, the end result was a lot better then the way I was doing it before, I was able to get the fiberglass on the tube tighter and even, I would recommend you try his way and check out his YouTube video, just enter his name on the search to find the video, sorry but I don't know how to post the video link here
https://youtu.be/_gTxwEVK6IY
Just learned how to post video thread
 
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Seems I'm digging up an old one, but figure that's better than starting over...
I'm about to try my hand at fiberglassing, and have found this forum (and John's videos) very helpful, but what I am missing is a list of what's required before you begin. John, is that on your site somewhere, and I'm overlooking it?
I get the basics, gloves, resin, fiberglass cloth, but there are some specialty items in there I'm curious about. For example:
What cloth weight? I get that it will depend on the purpose- how much strength is needed, if it's a veil coat, and that the lighter weight cloths conform easier, but are harder to work with. What's the best weight to start with, for a beginner, and that gives the best strength to weight balanced against ease of application (6oz?)? I can determine how much cloth I'll need for a given build, but what is the general rule of thumb for ordering? I'd hate to order what I need, as I need it...plus I'll need some for practice and messing up, so what's the best for someone just starting out with glassing (am attempting my L1 on a non-reinforced bird in a month). 10 yards? 20 (In event of Apocalypse and no more is available!) and what width? I was hard pressed to find a tube commercially available over 48" (BlueTube2.0 comes in 72", but...), so is 50" the best width?
Is there a reason most of the videos and articles I've read recommend epoxy as the medium, instead of polyester resins? Obviously the latter is much more challenging to work with (fumes, flammability, less viscous) but are there other reasons?
John- the paper you used looked to me like plastic-lined butcher paper, but I can't find it in 48"+ widths (seems to max out at 24, for wrapping meat). Is it something else? Can you share your source?
Same for the mylar- I've heard folks say heavy LDPE drop cloths work well too, but I haven't tested it.
Even little tips, like the fact that John had a masking tape dispenser handy, that was helpful! What sort of solvents are helpful (any generic ones besides those recommended by the manufacturer of the resin?)? Anyone have any killer rigs they'd like to share that make layup a breeze (although I'm smitten by John's tip-to-tip rig, and his wrap-layup technique requires no support).

I know my first efforts are going to be rough, and while I'm eager to learn, I'm not keen on reinventing the wheel (I would rather be on the shoulders of giants, as they say!).

Lots of questions, I know, so thanks in advance for ANY help or pointers thrown my way!
 
... what I am missing is a list of what's required before you begin. John, is that on your site somewhere, and I'm overlooking it?
https://jcrocket.com/epoxy-basics.shtml

What cloth weight? I get that it will depend on the purpose- how much strength is needed, if it's a veil coat, and that the lighter weight cloths conform easier, but are harder to work with. What's the best weight to start with, for a beginner, and that gives the best strength to weight balanced against ease of application (6oz?)?
Probably either 4oz or 6oz. I'm using 4oz in that video, IIRC.

I can determine how much cloth I'll need for a given build, but what is the general rule of thumb for ordering? I'd hate to order what I need, as I need it...plus I'll need some for practice and messing up, so what's the best for someone just starting out with glassing (am attempting my L1 on a non-reinforced bird in a month). 10 yards? 20 (In event of Apocalypse and no more is available!) and what width? I was hard pressed to find a tube commercially available over 48" (BlueTube2.0 comes in 72", but...), so is 50" the best width?
50" is the only easily available width, but you can use it long-ways if you need longer. I don't know how to answer the question about how much. I'd suggest ordering no less than twice what you think you will need, but don't order 10x in case you decide you want something else later.

Is there a reason most of the videos and articles I've read recommend epoxy as the medium, instead of polyester resins? Obviously the latter is much more challenging to work with (fumes, flammability, less viscous) but are there other reasons?
Polyester/vinyl ester resins are not as strong and harder to work with. I don't have personal experience with them, though.

John- the paper you used looked to me like plastic-lined butcher paper, but I can't find it in 48"+ widths (seems to max out at 24, for wrapping meat). Is it something else? Can you share your source?
It's just butcher paper. I have one 24" wide roll and one 48" wide.
Uline butcher paper

Same for the mylar- I've heard folks say heavy LDPE drop cloths work well too, but I haven't tested it.
Tap Plastic

What sort of solvents are helpful (any generic ones besides those recommended by the manufacturer of the resin?)?
Alcohol is just fine for clean-up and is non-toxic.
 
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I am about to start my first layup, and have received all of the materials to do this the "Coker way", and have a few additional questions.
1) Could a step be saved by wetting out the fiberglass cloth while laying on the mylar sheet, instead of wetting it out on butcher paper, and then wrapping in the mylar?
2) If two layers of glass are required, is it feasible to cut a piece that is double the circumference, and then roll it on two layers in a row? The other way I've seen is to wait until the first layer sets, but isn't cured, and then apply a second layer to get a good chemical bond.

Excited and nervous to do this :)
 
1) Could a step be saved by wetting out the fiberglass cloth while laying on the mylar sheet, instead of wetting it out on butcher paper, and then wrapping in the mylar?
No, I wouldn't recommend this. The fiberglass cloth will stretch as you roll it onto the tube. This stretching as you roll is a big part of getting a tight and wrinkle-free surface.

2) If two layers of glass are required, is it feasible to cut a piece that is double the circumference, and then roll it on two layers in a row? The other way I've seen is to wait until the first layer sets, but isn't cured, and then apply a second layer to get a good chemical bond.
I've never done two layers of the same fabric, but I don't see why you couldn't make a double-wrap. Just be extra careful to stretch the cloth so that you don't get any air bubbles. I would question why you'd want this, though, rather than just using a heavier-weight cloth in a single wrap.
 
Duly noted on the stretching, thanks!

You should probably know that I didn't necessarily heed your earlier advice, and I bought a lot of fabric all at once :eek:. I was looking for 6oz, but found 4oz at a terrific price, and couldn't pass it up, but it's 25yd. That's why I was asking about a double-lay up. I'll give it a shot!
 
Oh sure! I tell you, then you tell your friends, and next thing you know....

Kidding- I'm sure I didn't discover this place: thayercraft.com

Bought 25 yards of 4oz (38" wide) for $57, with FREE SHIPPING! Everyone else was selling similar for ~$5/yd. Thayercraft has a lot of "specialty" glass, so even though they have 6oz on the site, it's unidirectional, and would be more difficult for a beginner like me to use, I think. Although my order will likely keep me busy for a looong time, I wouldn't hesitate to order from there again! Super fast.
 
That is who I order form. You can get a lot of glass for a lot less cash.
 
Do you know if the offerings change periodically or is the inventory pretty consistent? Would like to still pick up some 6oz.


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