Home made peristaltic pumps - Page 12

germanicus81 · 12-28-2009, 05:51 AM

I just bought a load of homebrew gear from a guy getting out of the hobby, and one gem was this blue motor and gear thingy- a Little Giant LG-100 with motor and drivetrain. Here's a link to the pump on google, I will try to get some photos of the internals of the drive later. It's drive has two bearings that push on the tubing- rated for a little over 1 GPM.

Bullka · 02-02-2010, 03:19 PM

Does anyone know where I could purchase just a peristaltic pump (can be without the motor) that puts out the production of the silverbrew's design.
I am wanting to use this size pump to pull my wort through my CFC and into my fermentation tank.
I am fairly handy and could build / assemble the rest, but I don't have a machine shop to build the pump itself.
We brew 40 gallon batches once a month, so the faster the pump the better, to help speed up the process.
And like most home brewers I would like to do this as affordable as possible.

ajwillys · 02-02-2010, 08:06 PM

I got three of them on ebay for a steal. They are daisy chained together and turn from one driveshaft. They use 3/8" ID silicone tubing and have a max flow of about 2 gallons/minute at 650 rpm which is the max rated rpm.

I plan to use one or two of them for most tasks (synchronized HERMS recirculating, etc..) and all three simultaneously to really pump the bigger volumes of liquid.

silverbrewer · 10-02-2010, 05:09 PM

I have finally got around to the first test of the Mk2 pump, with it's three 1/2" silicone tubes. As set up in the photo, all three pump tubes prime ok from dry at about 20 RPM and at 66 rpm they combine to chuck out 2.66 imperial gallons per minute (so thats 3.2 USGPM or 12 litresPM) it still pumps right down to zero RPM, and stays primed, so that's a good sign! I'm sure if I upped the speed it would pump way more, but we will see later.

I now have to sort some manifolds to smoothly position the silicone pipes as they enter and exit the pump body and they will also clamp the pipe securely as the pipe definitely tries to creep into the pump, but surprisingly it goes the opposite way to the rotation of the wheel holder, so the tubes that are sucking get pushed out....weird.

For those new to this, the pump body is 12"dia 1/4" wall alloy tube, 51/2" long and the end plates are 10mm thick Perspex, turned to fit. The drive shaft is 15mm dia.

I am driving the pump with my lathe and the sash clamp coming up from the floor is clamped on to stop the whole lot turning! this will all be tidied up sometime soon.

The best bit is the brewery now has 3 pumps

Bumbler · 10-03-2010, 12:22 AM

That pump rocks!

It's come a long way since the first post. I love seeing new and creative gadgets. Keep pushing the envelope.

When you get there. I'm curious about flow rate as RPM's increase. Say from 40 to 80?

**airbalancer** · 10-03-2010, 01:38 AM

You don't see too many metal lathes on carpet

**conpewter** · 10-03-2010, 04:11 AM

Very cool, love the picture!

silverbrewer · 10-03-2010, 10:20 AM

The carpet was carefully selected/reclaimed from the stepdaughters dining room as it looked reasonably "Pub like"! I vaugely know someone who has his lathe in the kitchen!!! Needless to say, he is sans SWMBO.

silverbrewer · 10-09-2010, 02:04 PM

Using a similar setup to the previous picture but with improved inlet and outlet manifolds, I did 50 litre transfer tests at 105 rpm and 66 rpm. This gave an output of 5.6 and 3.141 US gallons per minute and took 7 and 10.5 minutes respectively. (Full results below)

Note that in the video, only one of the three silicone tubes is fitted, so the rectangular holes seen in the pump body sides are the access holes for the missing tubes. Also, the max speed is 105 rpm. Virtualy all the noise is the lathe, so when I give the pump it's own electric drive motor, things won't be so bad!!!!

http://www.youtube.com/watch?v=aOX1toND6ic

The plan is to use pump tubes 1 and 2 in unison for mashing in and doing RIMS circulation, during sparging I will be using pump 1 for hot liquor and pump 2 for wort, so I will be able to sparge without needing to keep checking the flow rates as the pumps flow rates are exactly the same as each other, and that will then save the as yet unused and therefore "sterile" pump 3 for transferring the cooled wort from the boiler to the fermenter.

It seems that the tube needs to be held tight so it forms a "triangle" around the rollers. Doing this holds it tracking true and stable. If you try to keep the tube against the outer rim, which is what I was doing at first, it just flaps from side to side and gets in a right state. I have lubricated the pump interior with silicone grease to help things along as well. I have no reason to need a higher flow rate than this and it is my intention to not go above 66 rpm.

I will now set it up and let it run for a few days to try and get a handle on how reliable the tube is. If it lasts a test of a few days duration I will rely on visual inspection before each brewing session and cross my fingers.

If I was doing this again I would make three individual pumps that can be slid onto the drive shaft as and when required, then the third pump which is there as an emergency backup for the most part, would get to see next to no use apart from cold wort transfer..

The figures are per minute flow rates for 1 tube, 2 tubes and 3 tubes.

Litres 7.14, 14.28, 21.42 at 105 rpm......4.76, 9.52, 14.28 at 66 rpm

Imperial gallons 1.5705, 3.141, 4.71 at 105 rpm......1.047, 2.094, 3.141 at 66 rpm

US Gallons 1.886, 3.772, 5.658 at 105 rpm.......1.257, 2.514, 3.771 at 66 rpm

**ThreeDogsNE** · 10-10-2010, 04:06 AM

How essential is the metal drum? Could the hose simply be pulled in tension over the rollers and still work adequately? It seems that could simplify construction considerably.