Epoxy mix pumps - Wooden Boat People2024-03-28T23:00:44Zhttp://woodenboatpeople.org/forum/topics/epoxy-mix-pumps?commentId=1312281%3AComment%3A133584&xg_source=activity&feed=yes&xn_auth=noI always mix by weight. You a…tag:woodenboatpeople.org,2016-01-23:1312281:Comment:1337822016-01-23T22:53:05.523Zchris towleshttp://woodenboatpeople.org/profile/christowles
I always mix by weight. You are far more likely to get an exact ratio. Years ago on my first boat, I ran short on hardener while doing the hull of the boat. At the time I didn't understand measuring glass to weight ratios and was winging it. A buddy bailed me out mid layup with a qt of west fast hardener. It even included a pump. I thought...sweet. Well, long story short, when you have a process that works don't go messing with it mid project. I used the pumps and wouldn't you know it one of my…
I always mix by weight. You are far more likely to get an exact ratio. Years ago on my first boat, I ran short on hardener while doing the hull of the boat. At the time I didn't understand measuring glass to weight ratios and was winging it. A buddy bailed me out mid layup with a qt of west fast hardener. It even included a pump. I thought...sweet. Well, long story short, when you have a process that works don't go messing with it mid project. I used the pumps and wouldn't you know it one of my flow coats didn't kick off. Bad mix. If you understood the wasted energy I spent scraping gooey resin, wiping with vinegar, scraping more, wiping with acetone, scraping some more.....etc etc you would never use those pumps again.<br/>
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One thing to note is that the ratio by weight is slightly differant by volume. Be sure to check whatever it is for your resin.<br/>
I use resin research which is 2:1 by volume or 2:.9 by weight. The easiest way for me is to understand what batches to make. I like stuff that is easy math.<br/>
My typical batches are like<br/>
10g resin/ 4.5 g hardener= 14.5 g total<br/>
20g resin/9 g hardener= 29 g total<br/>
40 g resin/18 g hardener= 58 g total<br/>
100g resin/45 g hardener= 145 g total<br/>
200g resin/90 g hardener= 290 g total<br/>
Or some mix of the smaller amounts depending on what I need.<br/>
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If I go over, I use the 2:1 ratio then to balance out. I.e. Extra 2g resin, add 1 extra g hardener and your total point to hit goes up by 3 ( counting the extra 2 g resin and extra 1 g hardener). What the pumps might be better for is a mess free dispenser. Pump your cup on the scale and pump you resin is slowly till you hit your target. I honestly pour straight out of gallon jugs, with a ketchup type west dispenser you could have no mess and check that you ratios are correct. In theory they should be right, but the scale will tell you wether you have a correct mix. If I would have done that on my first boat I would have avoided days of scraping and nasty chemicals.<br/>
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These mixes all fit in a 16 oz plastic keg cup form the dollar store. I use a cheap harbor fright gram scale. I keep it in a ziplock bag so it doesn't get all gooey. Much more difficult to mess up a mix this way. Pretty easy too.<br />
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Also, don't waste resin. It's expensive, and adding extra to your layup doesn't add any strength. For a hand layup the ratio of glass/resin is 1:1. If your glass weighs 200 grams, you need 200 grams total of resin. The math for that looks like<br />
Total weight /2.9 = A<br />
Resin= A x 2<br />
Hardener A x .9<br />
Double check your math before you mix! THAT is very cool. So good to…tag:woodenboatpeople.org,2016-01-21:1312281:Comment:1338432016-01-21T03:52:07.213ZBrad Dimockhttp://woodenboatpeople.org/profile/BradDimock
THAT is very cool. So good to hear a take like that. Kind of sad how few companies understand the value of trying to make things right.
THAT is very cool. So good to hear a take like that. Kind of sad how few companies understand the value of trying to make things right. All, good stuff. Thanks for t…tag:woodenboatpeople.org,2016-01-21:1312281:Comment:1336992016-01-21T02:39:00.234ZEric Berryhttp://woodenboatpeople.org/profile/EricBerry
<p>All, good stuff. Thanks for the replies, I'm gonna try that vinegar trick. I am adding a 16" wide strip of glass to each side of all of the scarfs and call it good. I bent all of the panels to a more sever degree than they will be on the boat, no signs of any distress. Feeling much better now.</p>
<p>As an aside....I called West System last Friday after I discovered the problem and left a message. They called back Monday morning, of course I was in the duck blind with a crappy cell signal.…</p>
<p>All, good stuff. Thanks for the replies, I'm gonna try that vinegar trick. I am adding a 16" wide strip of glass to each side of all of the scarfs and call it good. I bent all of the panels to a more sever degree than they will be on the boat, no signs of any distress. Feeling much better now.</p>
<p>As an aside....I called West System last Friday after I discovered the problem and left a message. They called back Monday morning, of course I was in the duck blind with a crappy cell signal. We finally made contact yesterday.</p>
<p>Two observations from that conversation. First, the tech (Tom P) really knows his stuff! He diagnosed the problem to a check valve in the resin pump. He also had strength values for improper ratios, very helpful in determining what my next step would be. Second, this company really stands behind the products they make! Had I got the chance I was going to ask them for a new quart of hardener, before I could, Tom told me they were sending a gallon of resin, a quart of hardener, a new set of pumps and a couple yards of glass cloth!</p>
<p>I cannot remember the last time I called tech support and found them to be helpful, let alone a company that stands behind their products. I was very, very impressed and felt they deserved some public kudos.</p> Dorf & Brad, thanks for t…tag:woodenboatpeople.org,2016-01-19:1312281:Comment:1335242016-01-19T13:00:50.576ZKurt Selischhttp://woodenboatpeople.org/profile/KurtSelisch
<p>Dorf & Brad, thanks for the vinegar tip.....good to know! Bye bye acetone!</p>
<p>Dorf & Brad, thanks for the vinegar tip.....good to know! Bye bye acetone!</p> Yes to Philip. Vinegar for cl…tag:woodenboatpeople.org,2016-01-19:1312281:Comment:1335842016-01-19T04:47:19.234ZBrad Dimockhttp://woodenboatpeople.org/profile/BradDimock
Yes to Philip. Vinegar for clean up. (from the dollar $tore) I either throw stuff away or clean up with vinegar. I use epoxy all the time and could not tell you for sure if there is still a can of acetone in my shop. Horrifically toxic stuff. Right up there with toluene, lacquer thinner, and WEST fast hardener.
Yes to Philip. Vinegar for clean up. (from the dollar $tore) I either throw stuff away or clean up with vinegar. I use epoxy all the time and could not tell you for sure if there is still a can of acetone in my shop. Horrifically toxic stuff. Right up there with toluene, lacquer thinner, and WEST fast hardener. Mixing cups, mixing sticks an…tag:woodenboatpeople.org,2016-01-19:1312281:Comment:1337452016-01-19T03:32:37.049ZPhillip Westendorfhttp://woodenboatpeople.org/profile/PhillipWestendorf
Mixing cups, mixing sticks and such can be cleaned up with White Vinegar too. It's a lot cheaper and easier on your skin. Works pretty good too.
Mixing cups, mixing sticks and such can be cleaned up with White Vinegar too. It's a lot cheaper and easier on your skin. Works pretty good too. Eric,welcome to the "Oops, I…tag:woodenboatpeople.org,2016-01-18:1312281:Comment:1337402016-01-18T15:17:38.262ZRick Newmanhttp://woodenboatpeople.org/profile/RickNewman
<p>Eric,welcome to the "Oops, I measured this batch wrong" group! I think is it one of the rituals we must all pass through. There are a few more coming up, your experience may vary!</p>
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<p>Rick Newman</p>
<p>Eric,welcome to the "Oops, I measured this batch wrong" group! I think is it one of the rituals we must all pass through. There are a few more coming up, your experience may vary!</p>
<p></p>
<p>Rick Newman</p> Yes to what Brad said. Inexpe…tag:woodenboatpeople.org,2016-01-18:1312281:Comment:1337372016-01-18T14:05:24.231ZKurt Selischhttp://woodenboatpeople.org/profile/KurtSelisch
<p>Yes to what Brad said. Inexpensive calibrated mix cups are easy to use and found at the local hardware store. When finished, swish a little acetone around in them and wipe out with a rag. They will be reusable for quite awhile.</p>
<p>Yes to what Brad said. Inexpensive calibrated mix cups are easy to use and found at the local hardware store. When finished, swish a little acetone around in them and wipe out with a rag. They will be reusable for quite awhile.</p> If your test fracture broke t…tag:woodenboatpeople.org,2016-01-18:1312281:Comment:1336682016-01-18T04:26:55.505ZBrad Dimockhttp://woodenboatpeople.org/profile/BradDimock
If your test fracture broke the plywood and not the glue, I'd say carry on, you're fine. But those pumps are notorious for inaccuracy. What is much easier than weighing is buying cheap plastic calibrated mixing cups. Just hold them at eye level and pour. Quick and easy, and you don't have to worry about getting epoxy all over your expensive scales.
If your test fracture broke the plywood and not the glue, I'd say carry on, you're fine. But those pumps are notorious for inaccuracy. What is much easier than weighing is buying cheap plastic calibrated mixing cups. Just hold them at eye level and pour. Quick and easy, and you don't have to worry about getting epoxy all over your expensive scales. Eric,
A word of caution!
If y…tag:woodenboatpeople.org,2016-01-18:1312281:Comment:1336622016-01-18T03:54:33.513ZPhillip Westendorfhttp://woodenboatpeople.org/profile/PhillipWestendorf
<p>Eric,</p>
<p>A word of caution!</p>
<p>If you use a digital scale , DO NOT weigh the resin and hardener to the same mix ratio as by volume. One liquid Oz of hardener does not weight the same as one Liquid OZ of Hardener. You need to read the manufacture's specifications to determine the correct ratio by weight.</p>
<p>Harbor Freight has a couple of low cost scales, 500 and 1000 Gram digital scales for around $10-$15. They work just fine. They are all I use, even as low as 10 Gram…</p>
<p>Eric,</p>
<p>A word of caution!</p>
<p>If you use a digital scale , DO NOT weigh the resin and hardener to the same mix ratio as by volume. One liquid Oz of hardener does not weight the same as one Liquid OZ of Hardener. You need to read the manufacture's specifications to determine the correct ratio by weight.</p>
<p>Harbor Freight has a couple of low cost scales, 500 and 1000 Gram digital scales for around $10-$15. They work just fine. They are all I use, even as low as 10 Gram batches.</p>
<p>G'Luck</p>
<p>Dorf</p>