Electronic Scale for Weighing Epoxy

C

Cushing H.

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I have discovered recently that the kitchen scale I have been "borrowing" from the kitchen to measure out epoxy, while pretty accurate for kitchen tasks, is woefully *inaccurate* for measuring out small quantities like 1-2 grams of epoxy and hardener. Does anyone have experience with a specific scale that you have found to be accurate when weighing down in the 1-4g range?
 
Any electronic reloading scale will work in grams. I have asmall one from Hornady, but there are several makers on inexpensive ones. Look at Cabelas or Midway, Brownells or Widener's.
 
PEU said:
I use one of these scales for epoxy, accurate and fast. At home I have another one for the kitchen condiments.
Cooking scales have an error of 5 grams, not good for the epoxy task, I prefer precision.

Pablo

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Yeah … ive “discovered” that error in my kitchen scale. Just because you can make it indicate grams, clearly does *not* make it accurately measure one gram…
 
Pretty much any cheap gram scale works fine. You can get them on Amazon for less than $15. Search Fuzion Digital Kitchen Scale. I weigh all epoxy mixing beyond a dab for odd repairs.
 
Wow been building knives for 20 years now. I've never measured glue by grams or ounces and never had one single failure. Just lucky I guess. I eyeball equal parts. Maybe it's more about surface prep and not over clamping. IDK
 
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I use a cheap one from ebay that goes 1/100gram.
One thing I found is that it works much better on a hard, flat surface like marble.
Also have a good look at the epoxy you use. The kind I use goes 1:1 by volume but 4:5 by weight
 
LCoop said:
Wow been building knives for 20 years now. I've never measured glue by grams or ounces and never had one single failure. Just lucky I guess. Maybe it's more about surface prep and not over clamping. IDK
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I originally bought it for precision but it also makes it much easier than trying to eye little measurement hash marks etc. I just put a beer can upside down on the scale. Tare. Put in the epoxy. Tare. Then squeeze in the hardener.
 
LCoop said:
Wow been building knives for 20 years now. I've never measured glue by grams or ounces and never had one single failure. Just lucky I guess. I eyeball equal parts. Maybe it's more about surface prep and not over clamping. IDK
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Usually i eyeball it also… but when i am making a wa handle, it takes a greater volume to fill the cavity, and eyeballing it just becomes a little less precise (hard to judge) because of the way the two layers sit in the small dixie cups i use.

I use gflex .. it only says 1:1 … but does not indicate by weight or volume. I think there us a fair amount of leeway in the actual ratios. Like i said, im just after reducing the occurance if where one bottle is empty and there is still a fair amount of resin left in the other bottle
 
LCoop said:
Wow been building knives for 20 years now. I've never measured glue by grams or ounces and never had one single failure. Just lucky I guess. I eyeball equal parts. Maybe it's more about surface prep and not over clamping. IDK
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And you can go 20 more without a hitch, thats completely fine. I moved to syringes and a scale because I buy epoxy by the kilo, so I put enough on a couple of syringes, mix exactly what I need and waste almost nothing, just a saving and efficiency thing.

Pablo
 
LCoop said:
Wow been building knives for 20 years now. I've never measured glue by grams or ounces and never had one single failure. Just lucky I guess. I eyeball equal parts. Maybe it's more about surface prep and not over clamping. IDK
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Feeling the same here. 450 knives made and never once weighed epoxy. .
 
Cushing H. said:
Usually i eyeball it also… but when i am making a wa handle, it takes a greater volume to fill the cavity, and eyeballing it just becomes a little less precise (hard to judge) because of the way the two layers sit in the small dixie cups i use.

I use gflex .. it only says 1:1 … but does not indicate by weight or volume. I think there us a fair amount of leeway in the actual ratios. Like i said, im just after reducing the occurance if where one bottle is empty and there is still a fair amount of resin left in the other bottle
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Another way to do it is to use a strip of duct tape, put the tape on a table or workbench . Squeeze out a line each of part A/B. Easy to see clearly how much you are laying down for each part. Mix together on the tape. Also the leftovers on the tape confirms your mixing bond when cured.

I realize we all have our own preferred method. This is just another way.
 
I think most of us who mix by weight are not using squeeze tubes. I buy epoxy in pints and quarts. There is no simple way to measure except a calibrated mixing cup (volume) or by weight. Weight is fast and easy. Another factor is that using commercial resins like West System and System Three there is no thickener in the resins, so they are liquid. You couldn't make two stripes on a flat surface. They have to be mixes in a cup.

When mixing a batch of system Three T-88 I put a plastic mixing cup on the scale and tare it. I add 100 grams of resin and then 83 grams of hardener. Plus or minus a few grams won't hurt, but the basic ratio for T-88 is 1:0.83 Resin/Hardner. I made a little chart with the amounts in 10 gram steps to make it less likely to make a bad mix.

TIP:
Epoxy curing is a thermal reaction. The speed of cure is relative to the temperature. The temperature will rise faster as the depth of the resin increases. Mix in a standard cup is good, but after mixing pour it into a wide and shallow container. They make disposable mixing and work-pot plastic cups as well as special silicone rubber work pots for this (you can use a wide flat silicone casting mold, too). Once the resin is fully hardened you just pop the extra out and the pot is ready for the next batch. The resin has a longer working life if it is in a wider and shallower layer rather than a tall cup.
 
Stacy E. Apelt - Bladesmith said:
I think most of us who mix by weight are not using squeeze tubes. I buy epoxy in pints and quarts. There is no simple way to measure except a calibrated mixing cup (volume) or by weight. Weight is fast and easy. Another factor is that using commercial resins like West System and System Three there is no thickener in the resins, so they are liquid. You couldn't make two stripes on a flat surface. They have to be mixes in a cup.

When mixing a batch of system Three T-88 I put a plastic mixing cup on the scale and tare it. I add 100 grams of resin and then 83 grams of hardener. Plus or minus a few grams won't hurt, but the basic ratio for T-88 is 1:0.83 Resin/Hardner. I made a little chart with the amounts in 10 gram steps to make it less likely to make a bad mix.

TIP:
Epoxy curing is a thermal reaction. The speed of cure is relative to the temperature. The temperature will rise faster as the depth of the resin increases. Mix in a standard cup is good, but after mixing pour it into a wide and shallow container. They make disposable mixing and work-pot plastic cups as well as special silicone rubber work pots for this (you can use a wide flat silicone casting mold, too). Once the resin is fully hardened you just pop the extra out and the pot is ready for the next batch. The resin has a longer working life if it is in a wider and shallower layer rather than a tall cup.
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What stacy said. Another thing is that when im filling the cavity in a wa handle, the resin needs to flow freely down into the cavity from the 1/8” slot st the front of the bolster. To help this, i use a heat gun to (carefully) raise the temperature of the resin in my mixing cup to make it less viscous .. it flows much easier that way…

Stacy … i think ill stick with my dixie cup: if i had one of those reusable silicone cups, iwould probably lose it 😒
 
Yes, warming the resin helps make it easier to pour down a narrow hole.
Dixie cups are fine, but when mixing up several ounces of resin, the silicone cups and bowls are really nice. I put them in the epoxy bin after use and they are right there next time.

Here is another trick for pouring epoxy down a wa or other hidden tang handle:
Stick a thin coffee/cocktail stir down the tang hole. Pour in the resin and the air escapes out the straw.

Tip #2:
They sell tiny funnels for less than a dime each. Serach tiny funnel on Amazon and you will see a 120 pack for $10. These make pouring epoxy down tang holes easy. They are 8mm wide at the bottom, which will flatten and fit most any tang hole. Warm epoxy slides right down them.
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