View Full Version : low LPM production (.25 LPM)

08-02-2009, 06:07 AM
Hi all. I've browsed the forums for a while and have just this week finished and started to tweak my plate array. I started with smack's design. On my first go around there was very little going on. The first thing I did was reduce the spacing (from about 3.6mm to about 2mm). Huge difference- from nothing to, well, something :)

When I made the above change I did it with just a single plate pair (why spend all the time re-assembling for nothing, right?). As I added plates I realized the bubbling was going down relative to adding the pairs. My best guess was that when I drilled the plates and tried to clean up around the holes that I made it so that the nuts were not making good contact. So I got some washers and put those in to try and maximize contact. This seemed to help and produced more hydroxy than I had seen yet. Because of the added washers I could only fit 6 pairs. I know nothing about electricity - at all. So I'm not sure if this is the right way to show you guys this (you'll be able to tell me if I'm right or not because if it doesn't match the Smack design then it's not what I meant to say) but I think this is what I have:


So I finally got around to measuring the out\put (submerged bottle and stop watch) and got the best result with baking soda (about 1.5 tsp for just over 1/2 gallon of distalled water) at 500ml at 1:30. This is a lot less than what I thought it would be. I should have been able to tell tho, the 'bubbling' was way less than what I've seen on the internet. Then I went to Ace Hardware and got some Lye. I tried that and I got a little less than with baking soda.

I've done a relatively thorough patching job, IMO. Basically I submerged the whole PVC tube in water except for the bolts at the top and hooked it up. I covered the output tube with my finger and watched for bubbles. Patched them and now I'm looking good but output is still low.

I know this might make it hard to troubleshoot, but I don't have an Amp meter right now.

Considering the above (and that I could get my hands on an amp meter) what would you guys suggest I do to troubleshoot my situation?

Thanks in advance...This forum seems like its got a lot of helpful guys on it.

08-02-2009, 02:45 PM
I just saw this video on youtube:


Does this mean that I should fire up the car to properly measure lpm?

08-04-2009, 02:32 AM
You don't have to put the cell in a car, just connect it to a car battery or other 12V source that can deliver plenty of amps.

For the plate config, try +nnn--nnn+ or just +nn--nn+ and see what you get.

Also, Rooto drain cleaner (contains NaOH) will give you better results than baking soda. Just be careful because it's caustic stuff and it heats up when you put it in water, so go slow. :)

08-04-2009, 03:11 AM
thanks! i actually ended up buying some of that exact stuff. i ended up using a about 1.5 tsp for around 3/4 gallon of distilled water. i still dont have a amp meter but i did take a temperature and it seemed stop heating up at around 105 and i got about .75 lpm. that's about 3 times as fast as i had been getting. so i have a question- who long does it take to 'warm up' ? if it was warmed up, then in theory i could add more accelerant, right?

08-04-2009, 03:13 AM
oh and by the way... how is:

+nnn--nnn+ different than +nnn-nnn+ ?

does the current pass better through a second connection to the set on the right? is that how it works?

08-04-2009, 05:13 AM
Well you can add as much accelerant (electrolyte) as you want but the cell will just draw more current and heat up faster. The "warm up" time really depends on amount of electrolyte, type of cell, etc... so I can't tell you how long that is.

I'm not sure about how the +nnn--nnn+ config works but I got the idea from the results of another post. I think it has to do with having the same surface area of positive and negative plates.

The best (efficient) way to get more production is through surface area: more plates or bigger plates.