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S34n
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+xAt a 25g batch size i would want to be using jewelers or weed smokers similar precision scales that can give you at least one or two decimal place accuracy. Then just round to the nearest decimal place you can measure to. eg if you have 2 decimal places, use those figures as is, if your scales are 1 decimal place then round to 17.2g and 7.8g respectively. Ok thanks warren appreciate your time
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Warren (Staff)
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At a 25g batch size i would want to be using jewelers or weed smokers similar precision scales that can give you at least one or two decimal place accuracy. Then just round to the nearest decimal place you can measure to. eg if you have 2 decimal places, use those figures as is, if your scales are 1 decimal place then round to 17.2g and 7.8g respectively.
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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S34n
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Group: Forum Members
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+xThe density of the mixed resin and hardener is NOT 1 it is 1.1g/ml. In very small mixes that you are doing, the difference is small due to the accuracy of the equipment available to measure it at that scale. That is why it looks the same. For larger batch sizes the difference is noticable. Very small batch sizes are not recommended due to the problems with accuracy for such small batches. It is easy for a small measurement error to be proportionally significant and causing a curing issue. Even the small amount of resin in the corners at the bottom of a cup can be enough to mess up the mixing ratio at small batch sizes. Sometimes for smaller batches it is better to accept a bit of waste from mixing a bigger batch but having the confidence that the resin will cure fully.
Hi Warren how accurate is the mix ratio chart on the bottle of resin,, should I use the maths equation 100:45 etc without rounding the numbers up or down?
so e.g. for 25g lowest number on the bottles mix ratio chart it would be:-
25 ÷145% = 17.24g( resin)
25 -17.24 = 7.76g (hardener)
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Warren (Staff)
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The density of the mixed resin and hardener is NOT 1 it is 1.1g/ml.
In very small mixes that you are doing, the difference is small due to the accuracy of the equipment available to measure it at that scale. That is why it looks the same. For larger batch sizes the difference is noticable.
Very small batch sizes are not recommended due to the problems with accuracy for such small batches. It is easy for a small measurement error to be proportionally significant and causing a curing issue. Even the small amount of resin in the corners at the bottom of a cup can be enough to mess up the mixing ratio at small batch sizes.
Sometimes for smaller batches it is better to accept a bit of waste from mixing a bigger batch but having the confidence that the resin will cure fully.
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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S34n
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Group: Forum Members
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+xYes and no. Grams No, ml yes. If you mix by weight it's still 100/45 or a multiple/fraction of that. You could use 20/9 by weight (No syringes, only a cup on a scale), wich would be close to your desired 24g. Syringes will give you a certain volume, therefore it's 2:1 By weight= 100:45 by volume= 2:1 Always. Ok oekmont thank you i'll give the 2:1 a try as I will need under 25g resin
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oekmont
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Yes and no. Grams No, ml yes. If you mix by weight it's still 100/45 or a multiple/fraction of that.
You could use 20/9 by weight (No syringes, only a cup on a scale), wich would be close to your desired 24g.
Syringes will give you a certain volume, therefore it's 2:1
By weight= 100:45
by volume= 2:1
Always.
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S34n
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+xIf you really need small quantities, get two 10ml syringes for a few pence. And than use the "by volume" 2:1 ratio. If you label both syringes for resin and hardener, you can use them multiple times, until the hardener syringe becomes clogged. So if I use 16g /ml of resin it will be 8g/ml of hardener?
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oekmont
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If you really need small quantities, get two 10ml syringes for a few pence. And than use the "by volume" 2:1 ratio. If you label both syringes for resin and hardener, you can use them multiple times, until the hardener syringe becomes clogged.
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S34n
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Group: Forum Members
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+xIf you are weighing the mixture, you MUST use the mixing ratio by weight which is 100:45 resin to hardener. If you are measuring by volume you MUST use the mixing ratio by volum which is 2:1 resin to hardener. Where possible, keep the maths simple by working with multiples or simple division of the mix ratio. That way you can calculate the correct proportions easily. Hiya Warren,thx for the reply This is whats confusing me, ml and g gives the same reading, i.e. if I pour 17ml of resin into a ml cup (the cup /beaker has been zeroed on the scales empty first) it will read 17g. If i need to use less than 25g which is the lowest amount on the bottle mix chart what should I do? Do I use the e.g. 16g x 45% math or the 2:1 method which i'm guessing would be 8 hardener for 16 resin ? so confused
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Warren (Staff)
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If you are weighing the mixture, you MUST use the mixing ratio by weight which is 100:45 resin to hardener.
If you are measuring by volume you MUST use the mixing ratio by volum which is 2:1 resin to hardener.
Where possible, keep the maths simple by working with multiples or simple division of the mix ratio. That way you can calculate the correct proportions easily.
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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