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scale for epoxy?

lawnboy

Member
what is everyone using for a scale to measure out epoxy? I don't know how to tell how accurate they are when buying one. if anyone has any advice id appreciate it.
 
You can buy the epoxy pump that meters out a fixed ratio of epoxy and hardener. West System has the pumps that sets the 5:1 ratio for its mixture.

Alternatively, if you are using only small amount of epoxy, a postal scale works fine as the densities of epoxy and hardener are similar. In the case of the West System, measure the components by weight. This is the system I used most of the time since I don't mix a lot of epoxy for the RV8. Also, pumping put too much epoxy will make it flash off very quickly, rendering most of the epoxy unusable.
 
Amazon has bunches and bunches of digital scales. Most any one will get the job done. Put mixing container on first, then turn on, add desired amount of resin, use calculator to do the math. Put in reading off scale and multiply times 1.10 for a ten to one to one ratio. That is the new weight of resin and hardener. Pour, mix, don't drink.
Art
 
I used this one. Pretty much anything that measures in grams will be accurate enough for sure! West systems 105/206 has a pretty wide envelope you can be in. If you measure by weight on West it is 5.36 to 1 but 5 to 1 also is in range.
 
Be careful buying the cheap digital scales. They vary greatly in accuracy. Had the metered Sticky Stuff pump building the Cozy, but sold that and opted for the scale method on the RV. West pumps are good but they do spit at times after long periods of inactivity. Not really concerned though as I only use West Systems for final fill and finish. MGS is my go to for anything structural. HF sells a small digital pocket scale that is very accurate and sensitive. I use that for small batches of epoxy and for measuring out flamemaster tank sealant, but for the larger 16 oz clear plastic deli containers from GFS, those don't fit well on that scale and I end up using the larger 10# capacity postal scale I use here at home. The digital kitchen scale I have at the hanger is junk IMHO and needs replacement. Not at all sensitive enough and I question its accuracy every time I use it.
 
Old Faithful. Rescued from a trash can 40 years ago.
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Like David, I used a Sticky Stuff pump for large layups when building my Long-EZ, but now that I only do small projects, I just use a triple beam scale. I picked an OHaus used in like new condition for $35. I tried the digital scales, but they are too "nervous", and I probably never had one that was good enough to trust. I totally trust the triple beam.

OHausTripleBeam.png

Like Larry, I like to put hardener and resin in dispensing bottles like sold for ketchup.

The triple beam has a knob/weight on the end that lets you zero out the scale for the common size plastic cup you like to mix with. If you stick with the same size container, you just have to do this once.

I keep a card near the scale that has resin and hardener mixing weights for all the batch sizes I will typically mix. With the triple beam, you start with the hardener, and set the weight down to the 0.1 g that you need, and then just dribble in the hardener while watching the beam end pointer until it rises up to the zero mark. There is no trying to remember the digital target and watching the numbers jump around. Just nice, well damped, movement up to the center as you add material.

TripleBeamScales.png

After the hardener has been added, you just slide the pointers up to the total weight of hardener and resin, and dribble in resin until the beam pointer again reads zero and you are done.

ScalePointer.png

Steve
 
I sometimes use the plastic communion glasses for mixing small amounts. Take a ruler and measure off the proper volumes on the side and add and mix. Saves a lot of epoxy on small jobs.
 
I park my HF tiny digital scale on a block between the resin and hardener. Dixie water dispenser cups have no wax and make excellent small batch pots. The hardener sits on a shorter block so the pumps can be rotated over the cup, then back for the final drips.

A stainless scale top makes it easy to clean, otherwise saran wrap cover seems to work well.
 
Epoxy scale

The $9 digital gram scale from Harbor Freight has worked well for me. It stays in a quart size thin Ziploc. I use plastic squirt bottles to hold resin & hardener and unwaxed paper cups in 2 sizes.

Don Broussard
RV9 Rebuild in Progress
57 Pacer
 
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