Epoxy Question

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studioseven

studioseven

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How precise do you need to be when mixing epoxy hardener with the resin? I normally just visually place around the same amount on a sheet and then mix them together. Never had any problems before. However last night, I had three different blanks separate when drilling on my lathe. The blanks had been glued two weeks ago. I was using the Systems 3 15 minute epoxy. Also could temperature be a factor? Working in my basement which is unheated and around 50 degrees.

Seven
 
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It is not critical but does need to be at least close and that should not be hard to do just by looking. I never measure but can look at it. More hardener is better than more resin but shoot for equal. Temp should not play a roll at least at that temp. I work in my basement too but it is around 60 degrees. Look at the label and it will tell you range.

40F degrees to 125F degrees is the range and they claim cures at lower temps too so

https://www.systemthree.com/products/quick-cure-15-minute-epoxy

If i were you and know you are going to work on any blanks of any kind weather segmented or full sized I would at least take them in a warm area to acclimate with a warmer temp before working them. You read many times here about acrylics cracking when turning or drilling and many times temps play a part in that. so why chance it.
 
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Thanks JT. BTW, the blanks were simple segments with plastic and metal credit card spacers added … three plies. Some of them held and some did not. Another thought, could of the drill bit heating up contributed to them separating?

Seven
 
studioseven said:
Thanks JT. BTW, the blanks were simple segments with plastic and metal credit card spacers added … three plies. Some of them held and some did not. Another thought, could of the drill bit heating up contributed to them separating?

Seven
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That is always a possibility but if you use a sharp bit and clean the hole and cool the bit then should have no problem. You also need to sand those plastic and metal pieces to give them some tooth when gluing especially materials like that.

Lets face it pen making can be and usually is very finicky. Just look at all the questions about CA that come up. Some people no problems, some people no problems one day and the next all kinds of problems. Just take note of what changes you are making and keep for next time.
 
If the consistency of the epoxy appears thicker when it is squeezed out of the bottle before mixing together, in other words its not in as liquid form before mixing as it is in normal /warmer conditions , I've had it fail in this state. So if its like this I will use my heat gun to warm up both bottles to where the liquid form is nomal and then proceed to mix a newer batch, and this I've not had a failure from. When its warm its easier to squeeze from the bottles.
 
Try this as a cheap way to get accurate measurements. Go to Amazon and get their little plastic medicine cups ($0.03 ea.) that measure in CC and ML. I use System 3 Epoxy so I measure 5.0cc of Part A and 2.5cc of Part B ($0.11/batch). Use a cheap plastic coffee stir stick (like what you get in the hotel coffee set up in your room), on Amazon they're less than a penny each. You can cut off the used end of the stir stick and use it probably 3-4 times. Total cost for a precise measurement is less than 15 cents. I can glue a whole bunch of stuff with just one batch. I just did 20 coffee scoop handles and a couple of cork extractor with just one batch. A little bit goes a long way and the System 3 Epoxy is not effected by weather, even if it freezes and I've used the same Part B since I started making knives (10+ years). I just recently had to buy a qt of Part A. And if you have any Epoxy left in the cup, let it harden and then pull the hardened Epoxy out of the cup and reuse it. I can usually get 2-3 batches per each little cup. And when I can't use the cup anymore I embed little items in the Epoxy which is kind of interesting. I have a whole bug collection sealed in Epoxy (they were dead when I stuck them in the Epoxy).😅
 
I can remember trying to glue up knife handles in the cold with 30 min epoxy and having some issues.

After mixing if the epoxy was cloudy and thick, I would warm it with a heat gun. Once it was clear and slightly runny I knew it would be okay. Epoxy needs some temperature to kick off the reaction.


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When i segment with plastic cards (credit, gift, junk mail) and/or metal sheet--i sometimes mummify the blank with gauze & CA until i can drill and epoxy the tube in. Turns off easily enough. It's really just a thin external cast to keep the drill heat from causing any issues--i lost a few in drilling before i tried 2 wraps of gauze with a CA glaze. I've also used painter's tape, and a few times on larger inside-out ornaments duct tape.
earl
 
Age of epoxy might be an issue, as well. I used some that is about 2+ years old this weekend and thought it would never harden. It ended up hardish, with a rubbery touch to the surface. a batch of fresh(er) epoxy hardened just fine, so environmental factors didn't seem to be a problem. threw the old stuff out.
 
For wood only
Never been a fan of thick fast drying epoxy .
I haven't use the epoxy in question , mainly because I use a slow drying epoxy with a one hr working time and the epoxy is thinner and absorbs into the wood farther and has more time to be absorbed into the wood grain .
 
pshrynk said:
Age of epoxy might be an issue, as well. I used some that is about 2+ years old this weekend and thought it would never harden. It ended up hardish, with a rubbery touch to the surface. a batch of fresh(er) epoxy hardened just fine, so environmental factors didn't seem to be a problem. threw the old stuff out.
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What brand Epoxy did you use? I've had the same Epoxy for over 10 years and it still works great. And it's even frozen a couple of times before I got the heater in my shop. I use the System 3 brand.
 
pshrynk said:
It was the 15 minute stuff that came with my PSI lathe. So probably pretty low end to begin with. The 5 minute stuff was, I think, Gorilla Glue brand.
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I have used CA for wood inlays ,,, normally I use west systems epoxy , I use west system for bonding and then another catalyst for a west system resin finish .
I use other finishes too , but I will not use any fast drying epoxy .

Most fast drying epoxy is really fast setting epoxy but still 24 hr cure meaning 5 minute epoxy means you can work with the epoxy for 5 minutes but a 24 hr cure time .
best of luck
 
Yeah, I always wait the 24 hours. This stuff just was still rubbery to the touch the next day. That's when I did the side by side test and the newish bottles of 5 minute were solid and felt hard while the older stuff was rubbery about 8 hours later. I tossed the old stuff and am ordering some new in.
 
wolf creek knives said:
Try this as a cheap way to get accurate measurements. Go to Amazon and get their little plastic medicine cups ($0.03 ea.) that measure in CC and ML. I use System 3 Epoxy so I measure 5.0cc of Part A and 2.5cc of Part B ($0.11/batch). Use a cheap plastic coffee stir stick (like what you get in the hotel coffee set up in your room), on Amazon they're less than a penny each. You can cut off the used end of the stir stick and use it probably 3-4 times. Total cost for a precise measurement is less than 15 cents. I can glue a whole bunch of stuff with just one batch. I just did 20 coffee scoop handles and a couple of cork extractor with just one batch. A little bit goes a long way and the System 3 Epoxy is not effected by weather, even if it freezes and I've used the same Part B since I started making knives (10+ years). I just recently had to buy a qt of Part A. And if you have any Epoxy left in the cup, let it harden and then pull the hardened Epoxy out of the cup and reuse it. I can usually get 2-3 batches per each little cup. And when I can't use the cup anymore I embed little items in the Epoxy which is kind of interesting. I have a whole bug collection sealed in Epoxy (they were dead when I stuck them in the Epoxy).😅
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Tom,

I'm a little confused, not an uncommon experience for me. I use System III also and I mix in a 1 to 1 ratio as best I can. But you say mix 5.0cc Pt A and 2.5cc Pt B What am I missing?

I like the idea of the small, disposable measuring cups. I already looked them up on amazon.

Frank
 
FrankH said:
Tom,

I'm a little confused, not an uncommon experience for me. I use System III also and I mix in a 1 to 1 ratio as best I can. But you say mix 5.0cc Pt A and 2.5cc Pt B What am I missing?

I like the idea of the small, disposable measuring cups. I already looked them up on amazon.

Frank
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Hope this helps Frank. My instructions say to use 2 parts A and 1 part B. I've under mixed in the past, by accident, and it takes forever for the Epoxy to set up, that's if it ever does.

Mixed at a 2:1 ratio, System Three epoxy has excellent pot life and cure-time control. (copied from Jamestown Dist.)

I did read that if you're using a high viscosity Epoxy you might do a 1 to 1 ratio. Here's a couple of sites to check out.

Jamestown Distributors

www.jamestowndistributors.com www.jamestowndistributors.com

www.systemthree.com

SECTION IV - MEASURING AND MIXING

Measuring and mixing is really easy with most of our epoxy systems because they mix at a 2:1 or 1:1 volume ratio.
www.systemthree.com www.systemthree.com

Here's the google search that I used to get this info. "system 3 epoxy mix rates"

I also use squeeze bottles for my Epoxy mixing by transferring the parts into separate squeeze bottles so that dispensing the parts is much easier. If you're interested in them let me know and I can send the info to you. I also bought them on Amazon.
 
Not sure where you are reading or what you are reading but adhesive epoxy is mixed 1:1 and coating or casting epoxy is a 2:1 ratio. Look at T88, 15minute, and 5 minute epoxy from System3. That is the stuff you want to be using for adhesive. The one adhesive that is a 2:1 ratio is their G2 epoxy which is made for oily woods such as teak. I have not used this product because I have had good success with T88.
 
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Can't comment on the brand your using as never tried it. I like 24 hr curing epoxy ie slow set and use araldyte brand. It does set better with slight heat upto about 60C and is stronger if cured at that sort of temp apparently the makers say. I stick in my airing cupboard at about 30C and it works well.

I do wonder if you're gluing metal if it has "keyed" to the metal sanding the surfaces to bond first helps
 
jttheclockman said:
Not sure where you are reading or what you are reading but adhesive epoxy is mixed 1:1 and coating or casting epoxy is a 2:1 ratio. Look at T88, 15minute, and 5 minute epoxy from System3. That is the stuff you want to be using for adhesive. The one adhesive that is a 2:1 ratio is their G2 epoxy which is made for oily woods such as teak. I have not used this product because I have had good success with T88.
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What I'm using is called a "General Purpose" Epoxy by System 3. It covers what you've mentioned above but is also used as an adhesive for wood and metal. Just read the Part A bottle for that info. I've been using it for a whole bunch of years and I've had no problem with it. I do let it cure for 24 hours though.
 
Every time I log into this site I learn something, and today I've learned a few things about epoxy. When I commented on this post a few days ago, I assumed the System III Quick Cure 5 was the only System III epoxy. With the help of Tom and others who posted on this thread, I know a little more about different epoxys, and have an appreciation of the System III company. Thanks.
 
Be aware of working times and curing times. They can be vastly different. There is also inverse relationship between strength and curing time. We really don't ask much from a pen /epoxy bond as long as we are using sharp tools. I have used many of the above including S3, and never experienced a strength/adhesion issue with any.

In anticipation of mixing epoxy, I lay each part out in parallel lines (assuming the beads are roughly the same diameter), I simply ensure the lines are the same length. That's just one way to do it that has worked well for me (gluing tubes).
 
wolf creek knives said:
What I'm using is called a "General Purpose" Epoxy by System 3. It covers what you've mentioned above but is also used as an adhesive for wood and metal. Just read the Part A bottle for that info. I've been using it for a whole bunch of years and I've had no problem with it. I do let it cure for 24 hours though.
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Be honest with you this is more of a fill or layer epoxy and thus the 2:1 ratio. It says it can be used as adhesive but need the right hardener for penetration into the wood fibers. Not made to glue metals as stated. Would definitely not be my choice for an adhesive glue. 3 other better products offered by them and I listed them.
 
Not an epoxy expert but did stay at a Holiday Inn Express once. Any epoxy I have used is 1:1 ratio. I did use one for coating fishing rod threads that was formulated to fudge about 10% for either part.
 
jttheclockman said:
Be honest with you this is more of a fill or layer epoxy and thus the 2:1 ratio. It says it can be used as adhesive but need the right hardener for penetration into the wood fibers. Not made to glue metals as stated. Would definitely not be my choice for an adhesive glue. 3 other better products offered by them and I listed them.
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Now you got me thinking John. After all these years with no problems maybe I'm using the wrong stuff. I looked up the T88 on their website and it's looks interesting. Maybe I'll give it a shot and see if I notice any difference. I'm just about ready to order some Part B so the timing is right. Funny thing is, Woodcraft was the one that told me to use this one way back when.
 
wolf creek knives said:
Now you got me thinking John. After all these years with no problems maybe I'm using the wrong stuff. I looked up the T88 on their website and it's looks interesting. Maybe I'll give it a shot and see if I notice any difference. I'm just about ready to order some Part B so the timing is right. Funny thing is, Woodcraft was the one that told me to use this one way back when.
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Well I am not trying to steer you one way or other but there is all kinds of info on their site about their products. They make all kinds of resin mixtures and application products. They are very reliable. I have used T88 for a long time on many different projects, not just pens and have been very satisfied. Now remember it is not clear. For that you need to go to the 15 minute or 5 minute line. Dry does not mean cured so keep that in mind too. The T88 gives me plenty of open time. Good luck.
 
I've used Devcon 30 minute epoxy for almost 10 years. I started using it for knife handles and have had no known failures. Several knives have made regular trips through the dishwasher without issues.


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Woodchipper said:
Not an epoxy expert but did stay at a Holiday Inn Express once. Any epoxy I have used is 1:1 ratio. I did use one for coating fishing rod threads that was formulated to fudge about 10% for either part.
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That qualifies you! 😁 Reminds me of back in the late 90's as numerous casinos were building in my home county. I went back home (from overseas) for a month and went into my local hardware store. A fellow I grew up with waited on me and I asked "where is your epoxy glue?" He said "we are out". Then he explained some "not from Mississippi" guys had a subcontract to do some PVC plumbing and came in and bought all they had the day before. My friend said, "we alerted the county inspector to check on them!"
 
jttheclockman said:
Well I am not trying to steer you one way or other but there is all kinds of info on their site about their products. They make all kinds of resin mixtures and application products. They are very reliable. I have used T88 for a long time on many different projects, not just pens and have been very satisfied. Now remember it is not clear. For that you need to go to the 15 minute or 5 minute line. Dry does not mean cured so keep that in mind too. The T88 gives me plenty of open time. Good luck.
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Good info and I appreciate your input on this John. The stuff I use now does dry to an amber, and I'm never in a big hurry so a longer curing Epoxy is just fine.
 
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