Glassing my first tube

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BDB

Absent Minded Professor
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I'm currently building a Terrodactyl by Binder Design, hoping to use it for an L2 attempt before the end of the year. I know it's not necessary, but I want to glass the airframe to make it more durable, but mostly because I want to learn the technique. I've been watching Coker and Tfish's videos over and over for the past few weeks and reading everything I can about it on TRF. Now I'm ready to order the supplies:

fiberglass fabric
4 oz: https://www.fibreglast.com/product/4_oz_Fabric_50_inch_wide_262/Fiberglass_Fabric
-and-
2 oz: https://www.fibreglast.com/product/2_oz_Fabric_241/Fiberglass_Fabric

laminating epoxy
system 2000 (60 min hardener): https://www.fibreglast.com/product/System_2000_Epoxy_Resin_2000/Epoxy_Resins
-or-
635 epoxy (medium hardener): https://www.uscomposites.com/epoxy.html
-or-
West Systems 105 + 206 hardener: https://www.uscomposites.com/epoxy.html#west (I can buy this at the local West Marine shop)

peel ply
I have no idea!!!


I think the plan is to wrap both the booster and the payload tubes with two layers, 4 oz + 2 oz (What is a "veil layer?"), and then to "recut" the fin slots through the FG with a Dremel. I won't vacuum bag, at least this time, just to keep it simple. I'll probably use a plastic scraper and a paint brush to apply the epoxy. Is that ok? Am I missing anything else?

I know that for every 10 rocketeers there will be 20 opinions about the best way to do this, but at this point, I'd appreciate any advice that I can glean from you guys.
 
I'm currently building a Terrodactyl by Binder Design, hoping to use it for an L2 attempt before the end of the year. I know it's not necessary, but I want to glass the airframe to make it more durable, but mostly because I want to learn the technique. I've been watching Coker and Tfish's videos over and over for the past few weeks and reading everything I can about it on TRF. Now I'm ready to order the supplies:

fiberglass fabric
4 oz: https://www.fibreglast.com/product/4_oz_Fabric_50_inch_wide_262/Fiberglass_Fabric
-and-
2 oz: https://www.fibreglast.com/product/2_oz_Fabric_241/Fiberglass_Fabric

laminating epoxy
system 2000 (60 min hardener): https://www.fibreglast.com/product/System_2000_Epoxy_Resin_2000/Epoxy_Resins
-or-
635 epoxy (medium hardener): https://www.uscomposites.com/epoxy.html
-or-
West Systems 105 + 206 hardener: https://www.uscomposites.com/epoxy.html#west (I can buy this at the local West Marine shop)

peel ply
I have no idea!!!


I think the plan is to wrap both the booster and the payload tubes with two layers, 4 oz + 2 oz (What is a "veil layer?"), and then to "recut" the fin slots through the FG with a Dremel. I won't vacuum bag, at least this time, just to keep it simple. I'll probably use a plastic scraper and a paint brush to apply the epoxy. Is that ok? Am I missing anything else?

I know that for every 10 rocketeers there will be 20 opinions about the best way to do this, but at this point, I'd appreciate any advice that I can glean from you guys.


A few things:
  1. The US Composites 635 stuff is great. I use that solely here. For laminating, I would use the medium hardener. For structural pieces like fillets, I would use the fast hardener. Note, I have the pumps but still measure the epoxy components by weight.
  2. You might find it easier to us a sock. Giant Leap sells a Kevlar and a "Easy-Glas" sock They are a tubular weave that you just slip over the tube, pull tight, and then wet out with epoxy. I also have used and still have some tubular weave fiberglass sock in various different weights and sizes.
  3. You don't need a dremel to cut the fin slots. When the epoxy is set but not fully cured it should be leathery. At that point, if you take an exacto knife or other razor blade you should be able to cut out the fin slots easily. You'll have a much tougher go if you wait until it's fully cured.
  4. Regarding Peel Ply and the Veil Layer: Most of your fiberglass weaves are too coarse for a smooth surface finish. They will leave a series of ridges that need to be filled. So, your can use a Veil Layer, which is a thin layer of very light tight weave like 2 oz. This weave is tight and the epoxy will lay smooth enough for just finish sanding before painting. The other option is to use peel ply. Peel ply is a material that let's epoxy pass through but it does not stick to the epoxy. The way you use it is when you get your coarse cloth down, you put a layer of peel ply over top and wet it out. When the epoxy is in the leathery stage or cured, you can pull the peel ply off of the fiberglass and the finish will take on the smooth nature of the peel ply sheet. It just takes a little sanding and your ready for paint. So, to recap, they are both 2 ways to get to a smooth surface finish.
 
Thanks, Nate.

I have considered the GLR sock. It looks like a pretty easy solution. Maybe I'm just asking for more pain than necessary by wrapping FG.

And thanks for clearing up the veil layer vs. peel ply. I didn't realize they were two separate techniques. Now that I know that, I may go with some 6 oz glass and peel ply because I can buy the 6 oz stuff at West Marine. Unfortunately, they don't sell peel ply.

Does anyone have any suggestions for peel ply? I've seen both the econostich and nylon stuff on Amazon, but I've also seen some people using other materials, like mylar.
 
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I have used mylar, it works but its also common get air bubbles under it that require filling. I have used a cheap nylon peel-ply from ACP that is perforated and it works well, and I get very few large voids.
+1 the US Composites 635 3:1 resin, its easy to work with and provides a hard surface.
Soller Composites sells CF, Kevlar, FG and FG colored/glow in the dark sleeve/sock products.
 
Thanks, Nate.

I have considered the GLR sock. It looks like a pretty easy solution. Maybe I'm just asking for more pain than necessary by wrapping FG.

Selfishly, I wish you were going with the GLR sock as I have two builds underway where I plan to try both (Kevlar and Easy-Glas) GLR socks, and it would be great to see your process.

One the builds, 4", has the Kevlar sock rolled onto the BT now, and I should be laying it up in the next week or so. The other build I will be using the "Easy-Glas" sock, which I am pretty sure is just a name as it does not appear to be glass.

I grabbed one of each simply for the hands on so I could broaden my experience.
 
The other build I will be using the "Easy-Glas" sock, which I am pretty sure is just a name as it does not appear to be glass.

I read somewhere that the easy-glass sock is not FG, but that the final result is pretty good, though not quite as strong as if one wraps traditional glass. Are you planning to use peel ply or something similar with the sock, or is it a fine enough weave that it won't be necessary?

Thanks to all of you who have replied. You've given me a lot to think about.
 
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I read somewhere that the easy-glass sock is not FG, but that the final result is pretty good, though not quite as strong as if one wraps traditional glass. Are you planning to use peel ply or something similar with the sock, or is it a fine enough weave that it won't be necessary.

Thanks to all of you who have replied. You've given me a lot to think about.

It's not fiberglass and they clearing state it. If you use the kevlar sock underneath it that tube will be rock solid.

One tip with the socks. before you cut the sock to length, apply making tape to the sock where the cut is and cut the sock in the middle of the tape. The tape keeps the ends from fraying. Also, in addition to the fin slots you can trim the overhang on the edges when the epoxy is in the leather stage easily with a razor blade.
 
I just did my first T2T using West and this peel ply : https://www.aircraftspruce.com/catalog/cmpages/vb7025.php?clickkey=4946 Veil layer and using peel ply are NOT mutually exclusive, if you have it on hand, it's a real time saver and prevents you from having to potentially sand through your veil layer or putty the surface to get a smooth finish.

That Teflon peel ply worked amazingly well over a 2oz veil layer, a quick 320 scuff sand and it's ready for a filler primer, that I just did. Surface requires sanding, but there is no fiberglass weave pattern visible. The only way to get a glass smooth surface with a peel ply material is with a mylar wrap.

I've been following this thread, and buying stuff form Aircraft Spruce. Good prices and quick turn around. https://www.rocketryforum.com/showt...E-Blue-Tube-Clone-Build&p=1580223#post1580223

Also be aware of timeline with your resin/hardner. Likely you'll be able to handle the tube in a day or so, but my West said 5 days to full cure, and at room temperature it took a full 5 days to harden. I sanded little patches each day, and it starts gummy and by day 5 is rock hard fully cured.
 
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I just did my first T2T using West and this peel ply : https://www.aircraftspruce.com/catalog/cmpages/vb7025.php?clickkey=4946

Worked amazingly well over a 2oz veil layer. Surface requires sanding, but there is no fiberglass weave pattern visible. The only way to get a glass smooth surface is with a mylar wrap.

I've been following this thread, and buying stuff form Aircraft Spruce. Good prices and quick turn around. https://www.rocketryforum.com/showt...E-Blue-Tube-Clone-Build&p=1580223#post1580223

T2T is next on my list of techniques! I've been avidly reading the same thread. It is why I'm planning my next scratch build with blue tube and T2T-reinforced plywood fins.
 
I'm believe the fiberglassing socks are simply drain sleeves. You can get 100' of it from Lowes for about $20 for 4" diameter and $30 for 6" diameter. At the very least, go look at them and compare.

https://www.lowes.com/search?searchTerm=drain+sleeve

No friggin' way!!! I'm stopping by Lowes on my way home today.

(BTW...is anyone noticing how TRF is enabling my procrastination at work today?)
 
T2T is next on my list of techniques! I've been avidly reading the same thread. It is why I'm planning my next scratch build with blue tube and T2T-reinforced plywood fins.

You do know that blue tube really doesn't need glassing, right? That's the beauty of blue tube.

Either way, I updated my post above just after you posted. Hopefully my first time around tips help.
 
I get everything composite related from this guy:

https://www.avtcomposites.com/cgi-bin/commerce.cgi?display=home

Great guy to deal with if you value customer service. He is also very knowledgeable and will gladly share it over the phone.

Addendum: Aeropoxy 2032 and 3665 FTW. Cures at room temp, has a crazy long pot life and is ready to go in 24hrs or less if heat applied. Use 3660 catalyst for shorter cure time/pot life for smaller projects. Used for fins below.



20160912_210903.jpg20160914_130346.jpg
 
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Are you planning to use peel ply or something similar with the sock, or is it a fine enough weave that it won't be necessary?

I will be doing this under vacuum using my vacuum pump (Joe Woodworker "Project EVS" design), polyethylene bagging with nylon peel ply, breather, and the Aeropoxy PR2032 and PH3660 hardener.

The Easy-Glas sock has a relatively smooth finish compared to the Kevlar. First up is the Kevlar so I expect that if will not be a completely smooth finish but that is fine and works well with the retro theme of the rocket, I just hope it is uniform and gravity does not pool the resin on the bottom side of the tube.

BTW here is a link to the vacuum pump if you decide to get deeper in this.
https://www.joewoodworker.com/veneering/EVS/concept.htm

Here is another link to a guy who built one and is coming off the same setup I originally had, which was using a venturi style vacuum generator then ultimately moving to the Joe Woodworker pump.

[video=youtube;QQABdpQu8rg]https://www.youtube.com/watch?v=QQABdpQu8rg[/video]
 
Does it make a difference if the fiberglass cloth & peel-ply is folded when shipped or should it be on a roll?
 
Does it make a difference if the fiberglass cloth & peel-ply is folded when shipped or should it be on a roll?

I have very limited experience on this as I have only used shipped and stored rolls of 2x2 3K carbon fiber twill and a 3 oz satin weave FG cloth shipped and stored folded. In both cases once it was wet-out they laid down fine. The two peel ply films I have used, Teflon coated and nylon were both shipped and stored folded and again once wet-out they lay down fine.

I can potentially see a problem with the uniformity of some weaves depending on the cloth if it is folded and unfolded.
 
All my stuff came folded, wetted out and went down with zero issues.

I have this pump on order: https://www.amazon.com/gp/product/B006C6WAHW/?tag=skimlinks_replacement-20

Word on the street is that it's top notch, and perfect for what we're doing.

Only downside is that the pump is a single stage. For vacuum bagging it will work fine. I use the Harbor Freight 2 stage pump for everything rocket related. More expensive that a single stage but it pulls down to 22.5 microns. Most single stages only pull down to 250 microns. The extra vacuum it pulls is very useful for degassing propellant and epoxy. You don't need to go down that low for vacuum bagging because the pressure differential is not really a factor at that point.
 
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Only downside is that the pump is a single stage. For vacuum bagging it will work fine. I use the Harbor Freight 2 stage pump for everything rocket related. More expensive that a single stage but it pulls down to 22.5 microns. Most single stages only pull down to 250 microns. The extra vacuum it pulls is very useful for degassing propellant and epoxy. You don't need to go down that low for vacuum bagging because the pressure differential is not really a factor at that point.

Understood. Thanks for the info and link. I plan on getting my L2 soon and looking to learn enough about mixing propellant to make a decision on if it's a path I want to go down.
 
You guys are giving me tons to think about.

If (more likely, when) I were to vacuum bag, would I need to reinforce the tube with a mandrel of some sort?--at least the end of the tube with the fin slots already cut in. Would some spare couplers work?

I have several old vacuum pumps in my lab that can pull at least 250 microns of Hg, so it would be pretty easy for me to evolve my techniques to include vacuum bagging.
 
I did a few tube wraps after watching the Cokers video.

After finding out a roll of butchers paper was like $100 , I put some taped some wax paper down on my banquet table and went to work . Sized my fiberglass fabric oversized but trimmed uniform to a single wrap.

Drew a line up and down the tube with sharpie .. good call was visible even after being covered with fg . Sprayed a little 3m adhesive at line and placed the start of the fg there and it stuck .

Mixed 1.5 times the weight of the glass in epoxy and started applying to the fg starting at the line . Basically had the line in front of me horizontal with the fg flat underneath layed out behind . As the fg drank in the epoxy it got translucent and wet and I rolled 'up' and slightly away from me as I applied the epoxy thoroughly and wetting out the material. The rolling back motion kept the material flush and mostly tight , but did not squeeze out any excess epoxy like Johns paper roll . Using brush swirls if it looked dry with extra epoxy , I applied and rolled until I got all the way around and passed the line I backed up a hair and cut across trying to have my fresh edge fall on the line . Recommend the 'free' Harbor Freight scizzors and wipe with alcohol or toss when done.

Next up was to take the wet tube and drop onto some flat mylar onto the clean waxy tabletop and roll and squeeze from the center out ..I could actually get the fg to shift inside and rerolled until it looked uniform again . Finished by cutting excess mylar off - left a flap , and requeezed by hand from center and taped to hold in place - trying to get mylar as tight as possible . First time I did have 'tube extensions' like Coker suggested .. and dried on skewered on a broom handle in the vise . Subsequent, smaller wraps I just wrapped and set mylar tube on end on the bench. It was messy , it wasn't perfect like John and TFishes but when I pulled the mylar off next day ..was pleasantly surprised


Did a get a perfect Coker tube ? Nope Did get a perfect T-Fish tube ( his videos are good too) no ..but I did get a 90 % smooth fg tube with some pinhole clusters and some dry spots to putty over . I was impressed because it basically took some epoxy, a brush, a $3 mylar square and some Bondo Fg ($4 at Wallymart) and my paper tube now had some very noticable elasticity and strength ..and finishing was less of a hassle, no spiral now and I could really sand on it..without worrying about rashing the tube . It was also easier to slot than a paper tube .

I used a $10 Estes PSII 4 inch tube for the Mega Der Red Max ..with some fg on the fins I flew on a H400 38mm vMax and then shredded it on a H550-ST ..two fins imploded but the tube was intact .. so mission accomplished .

Oh almost forgot ..it was about 22 inches long , weighing it , a 22" traditional fiberglass tube , and a 22" blue tube ..I found the fg tube to be heavy , the blue tube about 3/4 of the weight of the commercial fg tube and my wrapped tube was 60 % of the weight of the commercial fg tube .
 
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I had an issue with the Mylar - practiced on a BT-60 and when removing the Mylar the next day the FG surprisingly stuck to the Mylar and pulled the FG off the tubing destroying the tube. Might get the technique down prior to doing it in your L2 bird.

I also had butcher paper and some paper doesn't have the plastic coating on it. Just purchased some coated butcher paper, from our local butcher. Also will try wax paper.

Also FYI. I read if FG is folded and smashed this will break the glass fibers losing its strength so I wouldn't fold it or if you must do it lightly. My FG was shipped folded by loosely so possibly is ok

Great topic as I want to try / become proficient at glassing
 
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Folding glass or carbon at any point will stress the fibers and fracture them.
It may lay flat. The fibers are still weakened at the stress point.
Im just an aerospace guy though.
 
Baking parchment works well to wrap your tunes. I have used it along with tightly wrapped electrical tape to apply a Kevlar sock. It worked out nicely. You soy have to be careful not to crease the parchment or it will leave a line (lesson learned) but it was easy enough to sand out.
 

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