For some reason, this is all I can think of when I hear magnetic drive



All kidding aside, I'm not sure if this is a good idea or a bad one. My engineering side suggests that for this sole application, there is no reason to include a mechanical driveshaft; it makes sense to "skip the middleman" and drive the impeller directly with the magnets, at least for the sake of improving mechanical efficiency. On the other hand, I usually shy away from buying combination items -- when one part of the combo TV+VCR+DVD player breaks, the whole thing needs to be repaired/replaced.

So, I ask to those with more experience than I have: what is the usual point of failure in a rotary motor/pump system?

From what I have seen? The pump fails more, far and away. But I don't have much experience beyond my own Elektra restoration, and some people I know who've had pump failures. I haven't heard of a failed pump motor other than one that was damaged from a leaky pump. That doesn't really count, does it, being as the pump failed first?

Anyway, I'd defer to someone like Bill Crossland on that issue, but I figured maybe my 2¢ is worth 2¢ or so...

erics wrote:So then MAYBE, Version 1.1 of the GS3 will have this?

http://www.fluid-o-tech.com/files/TMFR.pdf

Well, my GS3 will.


The beginnings of a pressure profiling pump (link to photoset)

Tom (dsc) and I bought a pair of these together, and they've just arrived yesterday. I'm currently waiting on the electronics to give it a 5V supply and control it, so it's just sitting there looking cute for now.

The pump is small, even compared to the GS3's tiny pump/motor, and that's very cool. I have to admit that I am not sure how LM would fit the control box that converts the single phase power into 3-phase, though. That box is definitely not fitting in the GS3 as-is, and although it looks like it could be rearranged, it appears that there might be some heat generation concerns.

Of course, that just leads me to my opinion that the GS3 should have been designed with an external pump. I contend it'd be more portable that way, since the machine gets noticeably lighter when you take that big AC motor out. If they could rig up a reliable way to unhook the water line, it'd be cake to set the pump up externally and plug it into the machine somehow. And then you'd never hear another owner that dropped >$5000 on their espresso machine complaining that their machine buzzes so bad they have to hold their espresso cup under the portafilter to keep it from moving. Just my opinion, of course.

Wait one sec - I need to clear my throat

Looking good Nicholas - I almost made the $300 phone call the other day just so I would have something to play around with but then I figured the wife, daughter, dog, house, & Anita fill that bill quite fully. I am playing around with an Astra in the garage (readily & easily available 240 VAC) and rigged up this temporary tank for the machine's pump.

It MIGHT BE beneficial to set up the TMFR in similar manner having it ultimately discharge back to a reservoir through a 0.0125 to 0.0130 orifice. That way you could do some initial setup with the pressure transducer and process controller off-site so to speak.

Hi guys,

yup, good times ahead:)

Eric good idea, I might give it a try, especially since I have to check the characteristic of the pump before I finish the controller (voltage/pressure). I'll be taking the PT out of my Elektra for some copper routing, so might as well leave it out for a few days and do the tests.

Regards,
dsc.

A good idea indeed, Eric, though for me the transducer and process controller are a ways out... I'm planning on starting out with a 5V PSU and a 10KΩ potentiometer to man the controls. So I will be hand-profiling for awhile. I was thinking it would be extremely awesome to get a pot with ~120° range and mount it on the grouphead, actuated by... a paddle . Probably not in my future--I'll end up with either a process controller or some other device that can play back 20-40s "voltage profiles."

Nicholas/Tom, I'll be really interested to follow your progress on this one. I have been musing the possibility of converting the Synesso Sabre to something like this. Its not a Hydra, but I believe the plumbing is pretty similar (common pump splitting to independant water lines since it has to for volumetric purposes) so I think I could hack into it and convert one group for trials with this pump and keep the other two on the stock pump. Fair bit downtrack for this, so plenty of time to learn from you guys! Good stuff.

Cheers, Chris

Hi guys,

got mine today:D I'm surprised how small it is, I thought the control box is going to be much bigger. It's a very neat little pump and I'm sure I'll have lots of fun with it. Thanks again for making this possible Nicholas!

I'll start putting together the pressure profiling rig when I get back from Italy. Can't wait to be honest:)

Regards,
dsc.

Not to continue the hijacking of this otherwise dead thread about the Procon canned motor pump, I've started a separate thread devoted to the Fluid-O-Tech TMFR pump here. Continued discussion of the TMFR pump can be found there.