time:3h
time:3h


Author Comment Last activity Moderation
nshapiro "+1 to the time relay delay it could be adhered to the belly of the pump. Digging the flow meter debate! " | Read more » about 9 years ago
danbeavers "Mathew: Why would you doubt the accuracy of a stepped bore? A reamer will provide very accurate hole size and ball bearings have very accurate di..." | Read more » about 9 years ago
mathew "@danbeavers hmm... the variability in the break and its effect on flow could be quantified with a more accurate flow meter. I wonder how variable ..." | Read more » about 9 years ago
danbeavers "Another approach to this problem would be essentially what Drager does. We could construct a manual vacuum pump. It would essentially be like a b..." | Read more » about 9 years ago
danbeavers "Thanks Nate for posting my thoughts. I wanted to comment on Mathew's idea of calibrating the pump before shipment. I assume what is meant is that..." | Read more » about 9 years ago
nshapiro "@danbeavers just sent me a great email about cheap flow meters. he told me I could repost it, so am putting it here: "I have been thinking/researc..." | Read more » about 9 years ago
nshapiro "Gotcha. In my testing in 2011 i did some of the test and mailed test kits to those i couldn't meet in person. altho it wasn't statistically signifi..." | Read more » about 9 years ago
mathew "The vintage timers are probably far too massive. I'm not as worried about tampering as I am about good faith forgetfulness-- I don't always hear t..." | Read more » about 9 years ago
nshapiro "This is great. The vintage timers are pretty amazing although they add a lot of weight and thus money and are not tamper proof. We could just inclu..." | Read more » about 9 years ago
mathew "following up on our discussion about trying to calibrate the pump without the flow meter-- could we calibrate the pump at our office, and then have..." | Read more » about 9 years ago
danbeavers "Oh, I was making assumptions. I had not seen a pump that was set up to have 2 different attach points. So never mind about my comment! " | Read more » about 9 years ago
nshapiro "@danbeavers were you using the whisper pump or another pump? I think the whisper pump can handle one pump and one vacuum if need be " | Read more » about 9 years ago
danbeavers "On reversing the aquarium pump: Be sure and reverse both diaphragms! " | Read more » about 9 years ago
sadler "sorry for bring this post back from the dead but i want to build it :) so any suggestions for what material i should make the spars out of? " | Read more » about 9 years ago
warren "Hi, Nick - I'm working on some sketches of the kit; do you have any photos of the entire thing, just a bit more zoomed out? Thanks! " | Read more » about 9 years ago
mathew "I just bought the air pump components and a graduated cylinder to try and compare @davidmack's cheapo air meter... can't wait. I'm going to try us..." | Read more » about 9 years ago
straylight "Good points and I understand how you feel, coming at his from a chemistry teachers viewpoint myself. I guess it depends on what experiments and dem..." | Read more » over 9 years ago
srpratt "I'm new to the cellphone-becomes-a-photospec phenomenon, as I was told about this by a colleague. As an AP Chem teacher, I'm looking for hacks to ..." | Read more » over 9 years ago
nshapiro "I think so. Those tubes require one pump on the Draeger Tube proprietary pump. So if one were to rent their proprietary pump for a single day and a..." | Read more » over 9 years ago
sara "Exciting stuff! Do you think this method could work for other pump based tubes like these http://www.buydraegertubes.com/hydrogensulfide02b.aspx " | Read more » over 9 years ago
ichinarayan "ok thanks so much " | Read more » over 9 years ago
straylight "In spectral workbench, when you are looking at a spectra, there is an option to export and save the data in a variety of formats, including xml and..." | Read more » over 9 years ago
ichinarayan "wow beyond belief. i thought it was complicated listing program. and how do you exported the spectra image into csv form? thanks a lot " | Read more » over 9 years ago
nshapiro "That sounds like a great idea. The flow meter remains the most expensive component so reducing this cost is clutch. This sounds like something that..." | Read more » over 9 years ago