That is puzzling. I just repeated your experiment with my TF-100 chlorine tube and the one that came with my speed stir. They were the same. You are taking your measurements before adding the magnetic stir bar correct?I put 25 mm water in tube that came with the TF100 and then dumped it into the tube that came with the speedstir and it was very different. Same with the 10mm. My question is which tube should I be using for accurate results.
Yes bot kit tubes measure the same and differ from speedstir.Are both TF tubes (chlorine only and general use) producing different results than the speedstir?
If the accuracy of the test results rely on an accurate 10 mL sample of water, you should be using the Taylor cylinder. I spent a pretty penny on that repeating pipette, it should be pretty accurate for anything we do.I just took out my brand new just delivered tf100 kit and new speedstir and did the. 10 mm measure on both tf cylinders and poured into speedstir cylinder [without stirbar] and low and behold 10ml measured in the tf cylinders comes out to over 11.5 on speedstir cylinder!! I also confirmed by measuring out 10mil with a known good measuring pipe.
What gives ..this will throw off these relatively precise tests?? Should I throw out the speed stir cylinder and can I use the tf cylinders on the speed stir?
PS I am awaiting a call back from Wayne in tech support with Taylor to see what's up..I will post back here!
The cylinder that comes with the Taylor SpeedStir is the Taylor 9198. If anything, the measurement on the one from the TF-100 kit is off as the bottom of the meniscus is at the 10 mL line on the Taylor, whereas the top of the meniscus is below the 10 mL on the TF-100 cylinder.Not sure what you mean exactly we are discussing the measurement markng being off on the speedstir cylinder only. Wayne in tech Support is looking into it He was quite surprised to find out as this was the first call he took on it. I speculated the measurement markings were calculated with a flat bottom erroneously and the dimple on bottom is what has thrown off the measurents.
Again I will post back what happens here to follow up.
The SpeedStir cylinder is the clear plastic cylinder that came with the SpeedStir, it has no black lines marking the graduations.I have the tf100 and I am wondering WHAT IS THE SPEEDSTIR CYLINDER??? I do have the speedstir Thank you
This was the exact same situation as my cylinders. I tossed all the TF cylinders and only use the calibrated Taylor cylinders along with the Taylor Sample Sizer.I just pulled out my Taylor calibrated cylinder and the standard cylinder from the TF-100 kit and my Capp Rhythm Repeater stepper pipette. The bottom of the meniscus was very close to the 10 and 25 ml marks on the Taylor cylinder, whereas the top of the meniscus didn't quite reach the 10 and 25 ml marks on the TF cylinders. I would have to say the Taylor cylinder is more accurate. The precision of the 2 TF cylinders to one another doesn't mean they are accurate.