Best epoxy/resin for fiberglass in paper tubes

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azadulhaq

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What is your recommendation for slow as well as fast curing epoxy/resin combination for putting fiberglass in paper tubes? I need something that I can properly sand the next day after air drying overnight.
 
You can sand them all. Add micro balloons or spheres (filler) to make them more sandable. I use 5-minute epoxy from DEVCON or Bob Smith. Shop around for the best price.

5-minute will adhere well and you cardboard or wood will fail before the epoxy in most cases.
 
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What is your recommendation for slow as well as fast curing epoxy/resin combination for putting fiberglass in paper tubes? I need something that I can properly sand the next day after air drying overnight.
You want to laminate fiberglass around the tube? If so you will need a laminating epoxy resin. A quick setting, but good epoxy laminating resin I’d recommend is West System. The slow hardener will give you at least 25-30 minutes which should be more than enough time for a small tube. If it is a large one, then go with the extra slow hardener, which gives 40-50 minutes.
 
You want to laminate fiberglass around the tube? If so you will need a laminating epoxy resin. A quick setting, but good epoxy laminating resin I’d recommend is West System. The slow hardener will give you at least 25-30 minutes which should be more than enough time for a small tube. If it is a large one, then go with the extra slow hardener, which gives 40-50 minutes.
Good catch. I did not see that on my cell. For laminating, you going to need at least 45 minute of curing time.

I am partial to West Systems epoxy with the slow curative for laminating. Gives you ample time to work.
 
Here is a post I made last year about Hawk Epoxy, same as West system but softer on the wallet.
Hawk Epoxy has not gone up in price. I just checked and it's still $57.74 shipped to my door for the quart kit. That include resin, catalyst, filler and pumps. The same as West Systems but costs much less. Just got this kit a few weeks ago.View attachment 516204
 
Use use US Composites epoxies.
https://www.uscomposites.com/
I've had good luck with US Composites as well.

It has been quite a while since I've laminated a cardboard tube, but I don't know that I'd plan on sanding it the next day.

From the methods I've tried, the epoxy/fiberglass is rough and if you were to try to sand it smooth, you'd be sanding fiberglass as much as epoxy. I've used filler to fill the holes/mesh, but not tried to sand the fiberglass smooth.

I have not used any socks, peel ply or other methods that might yield a nice finish to start with, just wrapped by hand.

If you've never done it before, read up on people's methods, watch some videos, do a trial run on junk tubes and make sure you are well prepared with your work area covered, extra gloves, alchohol for clean-up and wear cloths that you don't mind ruining. Your first time will probably seem to go fine at first, but if anything goes off the rails, you'll realize your gloved hands are covered in epoxy and anything you touch will now also be covered in epoxy, so shed the gloves do what you need to do and then put new gloves on.

Wear nitrile gloves for sure! Epoxy can sensitize your skin and you will eventually have a bad reaction if you don't take precautions to avoid skin contact.

Sandy.
 
Not sure it is cheaper ay 101 for just the resin. Is there a better source than amazon?
The Bottom Paint Store. That post was from last year and yes the prices have gone up since I bought my kit.. I just checked today and they have the quart of resin for $39.71. Plus it's another 10% off with the code "epoxy10" at checkout. I did not see them offering the "kit" anymore and that's a shame as it was a great deal. Lots of good info on their site like the
 
I am a fan of Aeropoxy laminating epoxy. I use the 2 hour harder because I am OCD about it not hardening before I want it to, so I have a really long time to work with it and then I let it cure for about 24 hours.
 
I cannot disagree with the use of thin US Composite resins. Affordable and decent quality,
Fully agree. I've been using US Composites epoxy with fast and slow hardeners for over 15 years. If you're building a carbon fiber rocket to hit Mach 3, look for specialty resins. But the strength of ordinary epoxies is quite a bit more than enough for routine use in rocketry. Prices have gone up some, but you can still get a quart kit, with either fast or medium curative, for under $30 plus shipping. A gallon kit is just under $100.
 
I have a half dozen systems here and on my list to audition, but I really like the West Systems stuff I have used so far.

West Systems 105 Resin and 206 Hardener is doable if you are good, have all the tools, and are fast. 207 will give you more time, little less strength.
209 is the thinnest mix, should wet out best, lots of work time, LONG cure time... maybe too long for you? If it was just to protect the cardboard, I'd do 105/209 and light weight cloth, and eat the cure time.

207 should be available to sand following day, water clear, up to 3 coats in one day without additional cure/prep. 207 is also good enough as a structural adhesive too. Add 406 colloidal silica in varying amounts to get consistency for fillets, etc.

Alternatively, Get a 105C Resin, and 205A, 206A, 207A, and 209A hardeners and have a "quart" of each to try.
 
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I have a half dozen systems here and on my list to audition, but I really like the West Systems stuff I have used so far.

West Systems 105 Resin and 206 Hardener is doable if you are good, have all the tools, and are fast. 207 will give you more time, little less strength.

206 is not "doable if you are good"; its perfectly fine. I've used it on smaller than 3", a 3" (my Level 2), as well as a bigger 5.5".
 
206 is not "doable if you are good"; its perfectly fine. I've used it on smaller than 3", a 3" (my Level 2), as well as a bigger 5.5".

Check it out. We disagree. And that's OK. :) 206 has sufficient work time, but it's pot time is not particularly generous for lamination in my opinion, especially not a cylinder. I like all the time I can get. Y'all can read and compare for yourselves. Very useful documents... exact weight ratios, etc.

105/205 PDF

105/206 PDF

105/207 PDF

105/209 PDF
 
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I have a half dozen systems here and on my list to audition, but I really like the West Systems stuff I have used so far.

West Systems 105 Resin and 206 Hardener is doable if you are good, have all the tools, and are fast. 207 will give you more time, little less strength.
209 is the thinnest mix, should wet out best, lots of work time, LONG cure time... maybe too long for you? If it was just to protect the cardboard, I'd do 105/209 and light weight cloth, and eat the cure time.

207 should be available to sand following day, water clear, up to 3 coats in one day without additional cure/prep. 207 is also good enough as a structural adhesive too. Add 406 colloidal silica in varying amounts to get consistency for fillets, etc.

Alternatively, Get a 105C Resin, and 205A, 206A, 207A, and 209A hardeners and have a "quart" of each to try.
Thanks. I see 635 Thin Epoxy in US Composites website and 207/105 in West system website. I am sure they are different product.
 
This looks like a good place to leave this info for posterity, since there is a lot of discussion of USC 635. I emailed U.S. Composites asking about ratios for mixing by weight, as I think I can be more accurate with a gram scale than with a meniscus when doing small quantities. Response I got is below:

Here are the ratios for mixing the 635 resin and hardeners by weight:

2:1 Slow Hardener: 100 parts 635 Resin: 46 Parts 2:1 Hardener

3:1 Medium Hardener: 100 parts 635 Resin: 32 Parts 3:1 Hardener

4:1 Fast Hardener: 100 parts 635 Resin: 26 Parts 4:1 Hardener
 
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