So...when mixing your liquid with syringes do you count what's in the needle or it doesn't matter???
Mixing Question
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If you remove all of the air inside of the syringe when you are withdrawing your liquids, the fluid inside of the needle will remain there when you inject into your mixing container. You will get rid of it when you clean it out. You can get rid of all of the air by withdrawing the plunger...and reinjecting back into the source bottle if there is any air in the syringe in the initial draw. But in all honesty, I would not worry about it one way or the other unless you are making very, very small batches.
The previous entry aroused my curiosity about the dead space in the needle, so I loosely looked into it. I took a 14 gauge needle and slipped a 1.6 mm drill bit in (the largest in my micro set) and it fit just a little loosely, so let's say the ID is about 1.8 mm. The needle measured 55 mm from tip to base. So calculating the volume of a cylinder and converting mm^3 to ccs results in a dead space of around 0.14 cc (or ml). A finer gauge needle will obviously waste less liquid.
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WOW Jellyfish very impressive I must say. My batch size is 5ml for samples. I'm just trying to find the most accurate way to measure. Thx for the info.
vape Happy
vape Happy
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After you push all the liquid from the syringe into your bottle/container, liquid will remain in the needle, of course. If you pull air into the syringe and quickly depress the plunger, the air in the syringe will push the needle fluid into your container in a jet. Do this several times and you will get most of the liquid out of the needle.
I assume this volume of fluid is not counted in the original measurement, so you might want to use this technique to put the liquid back in its original container.
signed, .... Retentive
I assume this volume of fluid is not counted in the original measurement, so you might want to use this technique to put the liquid back in its original container.
signed, .... Retentive
Well glassmanoak, I'll join you in the '.... retentive' club. I've since found that a 14 gauge needle has an inside ID of 1.628 mm. That would result in a waste volume of 0.114 ccs in a 14 gauge needle.
We will be the charter members. LOL
I have a scientific background and MY being inaccurate or imprecise really bothers me. When I use a syringe for measuring, I draw a little air into the syringe first so that I can measure the liquid using the meniscus and not the bottom of the plunger. Then, the liquid from the needle goes back into its proper container.
As I said, .... Retentive Forever!
I have a scientific background and MY being inaccurate or imprecise really bothers me. When I use a syringe for measuring, I draw a little air into the syringe first so that I can measure the liquid using the meniscus and not the bottom of the plunger. Then, the liquid from the needle goes back into its proper container.
As I said, .... Retentive Forever!
Syringes are cheap and readily available. They work exactly as I want them to work and, as long as I cover the printing with tape or fingernail polish, they last a long time. I also use them to fill my carto tanks easily and quickly.
I've been a diabetic for over fifty years. I'm just way too familiar with syringes.
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