BYYB Forums

I'll admit I have had my problems with epoxy and still do.  However, I have eventually gravitated to a couple methods of mixing it such that I don't waste too much anymore.  The first thing I have come to realize is that it is better to mix two batches than waste a third of a big batch.  I pay real close attention to the amount I think I need and often times mix just short of that.  It seems that I am always surprised how far epoxy will go. 

I think the biggest thing is that I have developed a couple ways to mix very small batches.  I have assembled a mixing kit that is always used to mix now.  It consists of plastic cups, plastic picnic spoons, and pill bottles.  I am currently using West System epoxy.  For very small batches I use the plastic spoons to dip out five consistent spoons full from the resin can and with a fresh spoon, one from the hardener.  This is about the smallest batch I can reliably mix.  I don't have to wait to gather a bunch of laminating jobs so that I don't waste a larger batch.  This system has never failed me.  I am always careful to get consistent loads on the spoon, and unload them the same. 

For larger batches I have made up a couple pill bottles to use as graduated cylinders.  I like pill bottles because they are perfectly cylindrical from top to bottom.  I put a piece of masking tape on the side of each one and measure out equal distant line marks on the tape.  These marks can be any distance apart that you choose.  Mine are quarter inch.  On a standard bottle I can get eight to ten marks along the side.  Make sure to account for the thickness of the bottom of the bottle for the first mark.  I have one bottle for resin and one for hardener.  The words resin and hardener are very prominent on the side of each bottle.  With this I can measure out pretty precise amounts of each.  The biggest problem with these bottles is making darn sure that you don't lose count of how many units you have put into the cup.  Right now 25 units of resin and 5 units of hardener is about the biggest batch I will make.  I was able to apply a coat of epoxy to the entire bottom and sides of the SUP board I am making with this amount. 

If you keep the cylinders untainted, they will last a very long time.  I have built my canoe and the SUP board using the same bottles. 

What do you guys do to save on epoxy?

Al

With small batches (really small by my standards) I'll use syringes. I have several different syringes, I've gotten from a veterinary supply store. I can "suck up" a very precise amount in each syringe and squirt it into a mixing cup. My bigger syringes can suck up way more than several pumps from the West System style pump and it's very precise, with each being graduated. They are plastic and easily cleaned. In fact I have a can of acetone I use to hold the syringes, until I get a chance to clean them. They simply swim in the sealed can of used acetone, until I'm done with the epoxy run and can clean them. To address this issue, I have fresh acetone and used acetone containers. Anytime I use acetone and have some left over, I pour it into the used acetone can. This way I can continue using it, until it becomes a gummy mess, at which point it becomes a fine weed killer in the driveway cracks..

Acetone is wonderful stuff.  However, the last time I used that to clean up an epoxy mess I had to flee the shop.  It is so volatile that it can get to you very quickly.  Do you keep your syringes for both resin and hardener in the same bath?  What are you using for the bath?  I suppose a mason jar with a screw top could do it eh?  I tried syringes when I built my weekender, but found that the epoxy was too thick to pull through the neck.  I guess my shop was too cold for it to run much. 

I will try them again.  People can order them through veterinary supply catalogues or farm supply catalogues.  If you have a good relationship with a vet you could get them there too.

Al

There's all sorts of sizes for syringes, the more common ones will easily pickup goo, though if you try an insulin needle (I did once) you'll find it's way to small. I usually use a 12 cc syringe, but I also have 20 cc and bigger ones. The 12 cc syringe I can get for about a dime a piece, if I buy a case or about 30 cents each if I buy a pack of three.



I often place a vinyl tube over the end, so I can squirt it into places or around corners. I use a common acetone bath in a sealable plastic jug. Both syringes share this bath, which is simply a holding place until I can clean them. In time, the "used" acetone gets too dirty to be effective at much, so it's replaced, though during bigger projects, it gets enough use with excess acetone, that it doesn't go "bad".

I also use syringes. I dont clean them, because I let them always charge, I just put their cap on.
I have only to care for the piston gummy head that in the second component syringe doesn't slip enough and sometime disengages from the piston when I pull.
It is anyway wise to make tests before using any type of solvent on plastic and gum, because they could melt or change shapes (enlarge or shrink).

Gianluigi

That was the problem that I encountered with syringes the first time I tried them.  The darn rubber plunger kept pulling loose.  I haven't tried it yet, but I think I will try warming up the goo before I try to use a syringe.  A lukewarm bath will make it run pretty good.  Because it is a small  batch, I don't worry about it cooking off on me because it will be applied quickly to the joint. 

Al