Thread: Digger's resin - measuring catalyst?

I use plastic pipettes I buy from Barnes.

Pipette Dispenser - Barnes Products

Just noticed you can buy them on Ebay too.

pipette | eBay

Perfect - I was thinking I should pay Barnes a visit anyway!

You will find their resin is a bit cheaper as well.

I use a $10 eBay jewellery balance/scales and pipettes.

Get 2 pipettes and a small mixing container, I use the little scoops that come in powder detergent.

1) weigh and record the weight of the container (just in can things go wrong) and then tare the container

2) Suck up a small amount of catalyst in a pipette and dispense that into the container. Record the weight somewhere just in case things go wrong.

3) calculate how much resin is needed based on the amount of catalyst

4) Now using a second pipette weigh in the resin to desired amount.

If you are careful doing this you can mix as little as 1g (accurate to about 0.05 g) of total.
Doing it the other way (i.e. resin first) will not be as accurate as you are trying to accurately dispense a small amount of something to match a larger amount.

Because the catalyst goes in first you have to be extra careful with mixing and I mix it for at least 1 minute.

The $10 eBay scales are so cheap because they are used by the drug trade.
The one I have measure up to 300g and good to 0.01g
There are now 500g to 0,01g for less than $10
NEW 100G 300G 500G X 0 01G 0 1G Jewelry Gram Pocket Digital Balance Weight Scale | eBay

For $10 you can get this 1 PC 100G 1000G X 0 01G 0 1G Digital Pocket Scale BP N Jewelry Scale KK | eBay

I find lots of uses for scales around my shed but small resin/catalyst mixing is the most common thing I use it for.
I bought it at least 5 years ago and it still runs off the original batteries.

Thanks Bob!

I actually need a kitchen scale, wonder if I can make one of those do double duty! Will just have to cook things that don't need more than 500g weighed .

What is the preferred mixing ratio?

Originally Posted by rtyuiop

Thanks Bob!

I actually need a kitchen scale, wonder if I can make one of those do double duty! Will just have to cook things that don't need more than 500g weighed .

Kitchen scales tend to measure down to 1g - with the drug, er . . . . jewellers scales you can measure out smaller amounts.

Don't know how Digger package their catalyst , but I use Trojen brand on ebay and they package their catalyst in dropper bottles and it works out at 1 drop to 1gm of resin . Very easy for small amounts .
Ted

Where I buy my resin and MEK, they sell replacement caps for the MEK bottles with a drip spout that has a small screw-on cap of its own.

Don't know if it helps but I've always had a resin bought from the craft section in Bunnings [or from Spotlight et al] which is mixed 50/50, just like Araldite. All you do is look at the bottles to confirm with your eyes that the remaining amount is the same in each bottle. Sorry, can't remember the name of it and don't know if it's cheaper or dearer than Diggers. Cheers, George

Originally Posted by weldinggrump

Don't know if it helps but I've always had a resin bought from the craft section in Bunnings [or from Spotlight et al] which is mixed 50/50, just like Araldite. All you do is look at the bottles to confirm with your eyes that the remaining amount is the same in each bottle. Sorry, can't remember the name of it and don't know if it's cheaper or dearer than Diggers. Cheers, George

Not polyester resin like Diggers. More likely one of the epoxies

George it is diggers brand that they sell at bunnings and it is definately NOT a 50/50 ratio Dai Sensai is right (as usual) it is only epoxy that works like that. If you buy the small 500g or bigger tins from bunnings you will also need to get the catalist which I believe is held in the paint section (theft) It comes in a very small bottle with a dropper style and if you do about 30 drops per 100grams you will have no trouble at all. It will set no problem this will give you some idea and then you can slowly cut it down from there if you find it sets to quick


Cheers Ian

i have used the diggers resin, but i have now moved to using the trojan resin, much cheaper and better quality

i measure my resin by volume rather than weight, and i use 0.75% MEKP, 100ml of resin = 0.75ml of mekp, if its a cold night and i need to cast i might boost it to 1%

the more MEKP that you use will make the blanks more brittle, i also use the pipettes to measure the MEKP and any measuring jug with a 5 in the recycle logo will work for the resin

i am sure eveyone uses a different method, but its what works for you

i use this method for both clear casting and colored

all the best

MIK

I've gotten stuck with a couple of other projects, have to loop back around to this sometime soon! Thanks to all for the advice, I have a good few options now.