Epoxy Notes (Conap K-22 Black EasyPoxy)

[Mike Messer]

Some research and experimental data about Conap K-22 Black EasyPoxy (sold by PME and others) used by a lot of pipemakers, I think. It works very well, but must be handled properly.

The Conap Tech data sheets (from mfg. site: http://www.cytec.com/) make two statements which I think need to be clarified.

1. "Non-Toxic when cured" should read "Non-Toxic if cured"

2. "Relatively insensitive to mixing errors." It is an unspecified relative amount, and I made a small test batch with a mixing proportion error and it would not cure. It separated into a clear goo with little black areas and after 12 days I disposed of it, still uncured.

So, I made another batch using the following procedure and it cured fine.

1. Squeeze out 1/8" and dispose of it. It may be contaminated by air.

2. Hold the tubes vertical, pointed down, and squeeze out in 1/2" beads, measured with a ruler, then wiped onto a palate for mixing.

3. I mix thoroughly for 2 full minutes, on a flat, hard plastic sheet with a good, artists palate knife, the way artists mix paint, scraping it clean and wiping the knife on the palate repeatedly and mixing.

Other notes:
1. Pot life at 77 deg. F. is 20 min. You can double the pot life for each 18 deg F. below 77 deg.

2. Before I put any epoxy on my pipe parts, for example, bamboo shank - stainless steel. I put a big drop of the batch in an electric oven at 140 deg. F. for 20 min. to test the cure. Meanwhile to preserve the pot, put it in a cooler at about 50 deg. F. When the test drop is done and hardened okay, then proceed to glue the pipe parts.

3. I cure the pipe parts (and the leftover pot) in the oven at 140 deg. F. for 2 hours, and then, just to be safe, overnight at room temp, before working with it any more.

4. Epoxy has a shelf life which begins the day it is manufactured and which varies with storage conditions, and this is the reason for the curing test. Old or "spoiled" epoxy may not cure, ever.

5. Use good ventilation when heating Epoxy. The heat increases toxic vapor emissions, but accelerates the curing time and reduces the posibility of Epoxy Blush. Don't heat in a gas oven, Carbon-Dioxide, and Humidity are the causes of Epoxy Blush, a reaction which causes Ammonium Carbamate or Ammonium Bicarbonate to form on the surface. Both are toxic irritants.

6. Mfg specified curing times:
77 deg F. - Hard in 2 hours
Cured in 24 hours
140 deg F. - Hard in 30 min.
Cured in 2 hours

My testing showed this to be pretty much accurate, but note, a test batch at 60 deg. F. while very hard after 24 hours, did not fully cure for about 5 to 7 days.

7. When cured, Epoxy can be sanded and polished and is very hard, about Shore D 85, or better, about like Ebonite.

[T3pipes]

my method of - squeeze some onto a piece of cardboard and stir it with a scrap piece of briar for a bit - seems woefully insufficient now.

[Mike Messer]

my method of - squeeze some onto a piece of cardboard and stir it with a scrap piece of briar for a bit - seems woefully insufficient now.

It is. That sounds about like my first test that never cured, but I put a piece of a plastic bag under the porous cardboard.
When you squeeze it directly onto the palate, it mutates the form and it is hard to tell exactly how much is there, which can cause a mixing proportion error. It's really simple to measure it, like I said, and you get a perfect mix.

[KurtHuhn]

I've never used this stuff. Sounds like more trouble than it's worth.

I use Locktite 7-minute for plastics, J.B. Weld, and plain old 15-minute epoxy I get at the local hardware store. Mixing is easy. Measuring is by eyeball. I never do a test batch. I've never had a problem.

Locktite for delrin tenons.

J.B. Weld for knife bolsters and scales, as well as steel tenons.

Generic 15-minute for everything else.

[jeff]

Mike, you're over thinking this. I've made hundreds of pipes and have used many brands and bottles of epoxy. I have had curing issues exactly two times--both from too-old epoxy that I should have pitched anyway.

I use System 3 brand 5 minute epoxy, squeeze two similarly sized blobs onto a business card, mix with a toothpick for maybe 10-15 seconds and then use it. If the epoxy requires the kind of care you're talking about I'd get something else.

Hope this helps,

Jeff

[Mike Messer]

Kurt, Jeff, thanks for the tips. I'll have to try some of the products you mentioned.

All Epoxy is subject to shelf-life degeneration, mixing errors and mixing ratio errors leading to curing problems. If no manufacture date is on the package you don't know how old it is. You also don't know how it was stored all along the supply line. There are many circumstances and sources.

Maybe you have been lucky and have a good source and good instincts.
Everyone may not be so lucky, so I work with a method to assure the results. I'm not going to smoke through a pipe or ask someone else to smoke through a pipe which has concealed epoxy in it, unless I am damned sure it is 100% cured and with no blush. My method may be a little more work, but it isn't especially difficult, and I don't think it is over-thought.

You can skip the heated sample test and the batch cooling before assembly, and you can skip the heat curing of the assembled pipe, but you risk the porous parts of your pipe, if the batch doesn't cure properly, or if it blushes. And if you don't keep the left-over batch and examine it, you don't know what you have inside your pipe, even if it bonds. It may not be 100% cured and blush-free. I'm sure your methods are fine, but my method doesn't seem especially over-thought to me, all things considered.

[caskwith]

I've never used this stuff. Sounds like more trouble than it's worth.

I use Locktite 7-minute for plastics, J.B. Weld, and plain old 15-minute epoxy I get at the local hardware store. Mixing is easy. Measuring is by eyeball. I never do a test batch. I've never had a problem.

Locktite for delrin tenons.

J.B. Weld for knife bolsters and scales, as well as steel tenons.

Generic 15-minute for everything else.

Which locktite is this Kurt? Is it much better than epoxy or cyanoacrylate for delrin tenons? I have had one or two delrin tenons come loose when i tried to remove them from an overly tight mortise (in a handle i use for buffing, not in a pipe, lol) Im wondering if the glue isnt bonding aswell as it should and maybe there are more suitable glues. Devcon do a special glue for hard to bond plastics like delrin, but its insanely expensive and i wans hoping for a slightly cheaper option.

[KurtHuhn]

Which locktite is this Kurt? Is it much better than epoxy or cyanoacrylate for delrin tenons?

I don't know if it's better or worse than CA glue, but it's probably just about as good as any other epoxy. It's a two-part epoxy supposedly specially formulated for plastics:
http://loctiteproducts.com/products/det ... 9&plid=517

I found it one day while at the hardware store, decided to try it, and decided I liked it. So far so good. Then again, I never really has a problem with delrin tenons coming loose either, so I don't know if this actually gains me anything.

I also use the 5-minute epoxy Jeff mentioned. That stuff is great for shank caps and rings, and a host of other stuff. Plus it comes in big bottles, so even if you use a lot of epoxy the supply will last a while.

[ToddJohnson]

Mike,

You clearly need a hobby to eat up some free time. I would suggest you give pipemaking a shot. It's pretty straightforward and there are a bunch of seasoned professionals here who are even willing to help you out whenever you get stuck on something challenging. Think about it. That's all I'm saying.

TJ

[caskwith]

Thanks for the info Kurt. I need to get some new epoxy (my other stuff is starting to take a long time cure properly so its probably a bit old now) so i think i might do a little destructive test with delrin and both epoxy and CA glue in ebonite stems. See just how hard you have to push them to get them to break free. Thinking about it CA has a low shear strength so it might not have been the best choice, however i found it didnt cause any problems during stem bending whereas my epoxy was liable to fail after being heated.

[Mike Messer]

Mike,

You clearly need a hobby to eat up some free time. I would suggest you give pipemaking a shot. It's pretty straightforward and there are a bunch of seasoned professionals here who are even willing to help you out whenever you get stuck on something challenging. Think about it. That's all I'm saying.

TJ

I'm not having a problem with Epoxy. I just listed some notes about Epoxy. Maybe you should read it. It's accurate information.
MM

[baweaverpipes]

I believe I could have made a couple of pipes in the time spent testing.
A dollop of epoxy, a dollop of hardener, mix, apply.
Wish I could speed up the process.

[RadDavis]

A dollop of epoxy, a dollop of hardener.

Yeah, yeah. You damn liberals. A dollop here, a dollop there, and pretty soon you're talking about some real epoxy.

Rad

[flix]

I had similar issues with System Three T-88, only because I wasn't careful enough to mix it 50-50. How does T-88 rate with you guys as an epoxy? I was hoping this was the cat's meow of epoxies.

[ToddJohnson]

Mike,

You clearly need a hobby to eat up some free time. I would suggest you give pipemaking a shot. It's pretty straightforward and there are a bunch of seasoned professionals here who are even willing to help you out whenever you get stuck on something challenging. Think about it. That's all I'm saying.

TJ

I'm not having a problem with Epoxy. I just listed some notes about Epoxy. Maybe you should read it. It's accurate information.
MM

Okay, fair enough, I hadn't read it. The first time I only made it to #2. So I went back and read it fully. I have now concluded that either A) you are actually the artist formerly known as random, B) you are batshit crazy, or C) you're someone we all know who's pretending to be batshit crazy for your own amusement. I think you're funny, so you don't have to tell us which one it is. I like not knowing.

I do have some questions for you, though. Occasionally during the work day I'll go and wash my hands and dry them with a paper towel. I know a hand towel would be more eco-friendly, but it's just a habit I've gotten into. Anyway, sometimes the paper towel seems to be a little bit harder than I'd like. I've tested this particular brand in a lab setting and found it to have a Shore D hardness of around .62173966748565674589439665453434565778382811646478732899128171616356545362171882816166184122671
+/- .8278465637367253546573893202029384663672778283893939487747838383299283746346773838983939388, and a water absorption rate of around 27.23243575737653242424526346677278265253456278288263554643cc/min. at 4.75000000000000000000000 degrees Kelvin.

1) Do you think this is the optimal softness and water absorption rate for pipemaking?
2) Do you use starch when you iron your underwear?
3) Will you please study pipe cleaners next?
4) Do you know the circumference of your left nostril without having to measure?

I thought so! That's pretty cool.

All in good fun,

Todd

[Sasquatch]

I must be fuckin insane. I just squeeze some out of the red tube (or the white tube, depending on if it's 5 min or 24 hr epoxy) and some from the black tube, and mix it up, and the shit gets hard.

I use this method to stick things together.

I'm gonna take Todd's advice and try this pipe making thing. Looks like a lot of fun.

[Mike Messer]

Ref: Todd M. Johnson post, 2 prior, it's too long and ridiculous to quote.

Don't use paper towels; save a tree.
But, of course, wash your hands in hot water for two full minutes after using cloth towels which may be contaminated.

There is no "Random" as far as I can tell. He must be a figment of your imagination.
Crazy people never know whether or not they are crazy, else they wouldn't be crazy.
I'm not pretending to be crazy, as far as I know.
I'm glad you think I'm funny, but I think you have a weird sense of humor.

If you knew anything about Shore Durometer hardness testing, you would know that paper towels are not in the Shore D testing range. Shore D range would be harder things like ebonite or hard wood. Paper towels would probably be in the Shore OO range.
This is how us, more tech oriented guys know what-the-f we are doing.
As for water adsorbson... never touch the stuff. Fish f in it.

[baweaverpipes]

A dollop of epoxy, a dollop of hardener.

Yeah, yeah. You damn liberals. A dollop here, a dollop there, and pretty soon you're talking about some real epoxy.

Rad

[RadDavis]

Don't use paper towels; save a tree.
But, of course, wash your hands in hot water for two full minutes after using cloth towels which may be contaminated.

Cloth towles will impart a musty smell to your hands and then to any pipe you may be making.

Use paper towels; save a pipe.

Rad

[Sasquatch]

Note to self: Do not use Rad's towel.