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Bob Perkins
11-06-2003, 10:06 AM
Hi Everyone,

I'm happily planking along the bottom of my boat ... But a real P.I.T.A. are the crummy hand pumps on the epoxy bottles.

I've seen the hand crank geared pumps and thought... boy those are nice.. So I stared hunting and they seem quite pricey ~$250 and up :( A lot of money for convience I suppose.

Has anyone come across a less expensive way to do the same thing? Or found less expensive (and not crappy) pumps?

Just wondering....

Thanks

Ian McColgin
11-06-2003, 11:23 AM
I've not had problems with WEST pumps for casual use, but high production boat yards use the high grade, not plastic, cleanable pumps.

If you're used to normal work in chemistry, you can move about as fast with a beam balance. Put your container on - matters not if it has some of last batch's residue - and get the arm balanced. Move the weight out (for WEST) five units, whether oz or half oz or metric matters not at all either. Pour resin till the arm balances again. Move out one more unit and pour the hardener. What little error you may have at the tail of each pour will be porportionate at each stage so even that does not matter.

G'luck

Bruce Hooke
11-06-2003, 11:51 AM
Dang that's clever Ian. I could kick myself for not thinking of that method. When I've used the scale I've used the pump to add the resin, which means I end up with a hard to deal with number. Then I calculated how much hardener to add, which is always a bit of a pain and prone to error. I'll have to try to remember your method for the future...

Bob, what sort of problems are you having with the pumps? I've been using the West pumps for years, and aside from them getting sticky if I don't use them for a year or so, and needing replacement every decade or so, they have worked great for me.

Bob Perkins
11-06-2003, 11:58 AM
Hi Guys,

I'm using MAS epoxy and their pumps are slow. Warming the epoxy would help...(Shop is 56 deg)

I had the luxury of using the crank style (with the big hopper of goo) and It was real easy. (Got spoiled) I figured when it came time to glass the bottom w/4OZ cloth - I'd want bigger batches, etc.

I guess I could get one of those nice flat plate kitchen scales - but it in a plastic bag in the shop, and measure and weigh that way. Just pouring the stuff instead. When the boat is done - I end up with a scale smile.gif

But the hand crank pump was sure nice...

B_B
11-06-2003, 12:30 PM
I too had issues with hand pumps - on the hardner the ball bearing valve usually got stuck in the open position - WEST system.
A real PITA; ended up just measuring everything - found a container (small yogurt cups) and measured five of them into a larger container, marked it off, mixed the two in other containers, and away I went...

Figment
11-06-2003, 01:04 PM
Me too. When doing any large-volume task (planking that runabout sure would qualify!) I just pour into premarked cups. I've found that this is plenty accurate when mixing 8 ounces or more.

Save the squirt-squirt pumps for smaller batches.

Barrett Faneuf
11-06-2003, 03:04 PM
I use the marked-cup method for small batches, too. I have a "master" cup that I slide the next (disposable plastic) cup into. It has the marks that I put here for either 2:1 or 4:1 mixing. Pour to the lines and go.

I would have done a beam balance but I'm too cheap to buy one.

Cups work great.

NormMessinger
11-06-2003, 03:10 PM
The pumps are okay. Attitude may not be. tongue.gif

I made my own balance when I built the Long EZ. It worked fine but after the project was over and the bills all paid the little extra, relatively speaking of a proper despensing system seemed like it would have been worth it.

Wild Wassa
11-06-2003, 03:25 PM
I find, that if I keep the nozzels clean and the chemicals close to a temp of 20C/68F, even $14AU pumps work. If they don't, check your dispersal of the chemicals in the solutions and their temperatures.

One thing I have found after destroying a pump, was that it had not been assembled correctly during manufacturing. Definately not user error.

Warren.

ps, I only have a pump on the hardener now, too slow with the resin.

[ 11-06-2003, 03:31 PM: Message edited by: Wild Wassa ]

George Roberts
11-06-2003, 07:03 PM
Bob Perkins ---

If you take your time, the pumps work and they work well. Most people don't take the rigth amount of time.

I prefer to mix a bit off ratio and use an electronic scale. Tare the container, squirt in an even number of oz of resin, tare the container, and squirt in the proper weight of hardener.

warthog5
11-06-2003, 07:55 PM
I don't use pumps, I found them not to be accurate.
I use FGCI's 2 to 1 epoxy and that ratio makes it easier. The stats on it are slightly higher than System 3, but so close that it isn't worth checking.
Here's what I use to pour the epoxy. I just measure it. I can get as small as a few grams in a little pill container.
These are available at auto paint store's. It's what they use to make up the color you want by pouring this color and that color. I take the paddle out and throw it away. The spout is spring loaded.

http://www.imagestation.com/picture/sraid83/pa28be10bd01f5b1dbdc9c67b2eab5834/fae4f378.jpg

Dan Cavins
11-06-2003, 08:17 PM
Just for the record my West pumps have worked great for five years. Now I'm just a back yard guy, one boat at a time. One thing though, the temperature is key. When it gets colder they really slow down. A space heater and a box around the containers does the trick for me. Also if you have the big resin (5 gal.) container make sure there is a vent hole. Forgot about that at first, tough sledding. Dan.

JimD
11-06-2003, 08:30 PM
Bob, I think your pump problem is partly if not mostly due to the cool temp of your workspace. Those screw on pumps just can't pump epoxy that's thick as molassas due to the cold. Same thing has happened to me and warming the epoxy made a big difference. I'd just set the resin and hardener cans in a big tub of warm water, then no prob with the pumps.

Bob Perkins
11-06-2003, 10:14 PM
Thanks everyone - I brought the epoxy in the house to warm over night and it pumps much better. So a simple solution.

I may still do the scale for larger batches when I get that far.

But I'm still envious of the cranky pumpy thing smile.gif

[ 11-06-2003, 10:18 PM: Message edited by: Bob Perkins ]

John Gearing
11-06-2003, 10:17 PM
I think that MAS pumps suck (or rather, that they don't suck....properly, that is). I bought a standard MAS kit with pumps and in no time at all one of the pumps died. The ambient temp was not less than 70 degrees F during this time, AND the material was easily pourable at the time the pump gave up the proverbial ghost. Like the others here, I switched to simple measuring cups and had no problems.

Bob Perkins
11-06-2003, 10:20 PM
John,

I do agree - When I used West System - their pumps were much better.

I haven't tried the System 3 pumps...

davef
11-06-2003, 11:35 PM
The easiest time I ever had was with an inexpensive digital scale. Allowed for very precise small batches with none of the fuss and mess of different containers, etc. I'd just drop a cup on the scale, tare it out, add some epoxy. Use a hand held calculator to compute the ratio (5:1, 4:1 etc depending on the epoxy); tare the scale again and add the correct weight of hardener. I can't vouce for the following scale but at $30 it seems it would be hard to go wrong.

Ebay has a ton of such scales.
http://cgi.ebay.com/ws/eBayISAPI.dllViewItem&item=2570454769&category=11814

Simon Harwar
11-06-2003, 11:45 PM
Pumps the man asks?

Michaels Engineering makes them.
Keep the Epoxy in the temp range on the spec sheet from the makers.

JimD
11-07-2003, 12:11 AM
I don't bother with pumps at all anymore. Graduated measuring cups only. Perfect for any size batch. If you're mixing a few cupfuls for a reasonably large area it gets to be a lot of pumping.

JimConlin
11-07-2003, 01:55 AM
My work space is sometimes cool, so I keep a heat lamp or two on my epoxy bench. If the goo is warm, the mustard pumps work fine.
I use primarily WEST 105 epoxy. Some others are too thick outside of summer.

Aramas
11-07-2003, 03:04 AM
I gave up on pumps. Who can remember if that was 114 or 115 pumps? And if someone interrupts...

It takes forever for big batches. I just use disposable cups.

Now if I could just figure out a fast easy way of mixing it - especially with filler added. Man that wears the wrists!

frameshop
11-07-2003, 10:17 AM
has anyonr tried to use the large laundry detergent containers that lie on their sides with a small valve you push to dispence the fluid? I have been thinking of trying one.I don't know how the epoxy and hardeners would affetct the rubber in the valve but it seems like the ideal way to dispence. I have lost a lot of epoxy over the edge of the can over the years. I use the small(1/2 pint, 1 pint and 1 quart) containers from Jamestown Dist. they are real cheap and have graduated mixing lines on the side.They also sell those large wooden paint stirrers which I like for mixing.I've lost count on the pumps to many times. Roger

NormMessinger
11-07-2003, 10:48 AM
Hey, an epoxy pump dust up!

In my experience: I've used WEST, MAS and System Three pumps and have pumped, maybe 20 or 30 gallons through them. Looking back there are better ways but up front the price of a proper epoxy pump never seems justified. Anyway, the pumps are made for catsup and the like, right, and the epoxy folks have found them suitable. They can fail, in my experience, from a little crystal of epoxy getting under a ball in the pump and allowing some back flow when pressure is applied. So at least occasionally dispense into a measured cup to be sure the proportions are close enough.

Just how accurate are the graduations on pill cups? A ml of resin and a half ml of hardener, plus or minus 10%? I doubt it so use messy graduated syringes but we all have our methods and we mostly never sink.