Ok Marci, no problem, I was just trying to help out.

If there is already a solution out there, then not much use in making a mold.

Unless you think using jewel bearings will be much of an improvement?

Since I do not have any of these meters, I do not know if there high quality.
Our expensive lab meter has jeweled bearings, and very un-restrictive flow, and I am basically copying that design using magnets we are already producing.

That's a nice site. I can't buy anything from anywhere but the USA though. I have to have detailed and accurate delivery time on shipping as I travel for work and must be home when it arrives or it will be shipped back as there is no one here to receive it. I only get about a week a month were I know I will be home.

Dont stop mate, those innovatek ones kill flow big time, Ive tried them before & lost 50% of flow because of them..

low loss flowmeter would be a biggie for me & many others Im sure.

Yep, I was referring to the guy on WizD forums' project - basically a waste of time when it's already been done, however the Innovatek ones are 1/4" BSP for 8mm OD Tubing, so imagine the ID if you will ;)

A cheap 1/2" ID suitable alternative is certainly required... and I'd definitely have a load off you Dave...

However, rest of those in the uk, if desparate, head to rswww.com and type "compact flow sensor" into the search box.

Retails at £41 for one off, £39 for 6 off. Certainly an alternative for those in the UK...

They also do one suitable for -25 deg C thru 125 deg C, pressure drop of 1bar at 1cSt - £78 a piece.

They do a dirt cheap one for 15mm diam tubing, if you can adapt it down it may be suitable... only £20.37. Type "Liquid Flow Sensors -15mm dia Pipe" into their search box.

Basically, rswww.com > Automation > Fluid Management & Control > Flow Transducers (if you want to walk yer way thru the catalog and see all the options)

looks good marci, cheers for that.

Just ordered one, will hook up to my fanomatic pro & see how I get on (controller allows you to enter the pulses/litre of the flow sensor so should be reasonably accurate)

Aye, have used the fanomatics in the past... let us know how you get on...

Guys at DD seem to want a flow meter, so I will go ahead with a mold.

There is no big developement costs here, I have been doing this on my own, using parts AVT already developed, and C-Systems has 1000's.

I designed for a cheap two side MUD insert, so no one here will mind if I use one, and even if we only sell 100 of them, that will cover on mold cost :)

Just out of curiosity? How much will it cost?
How low cost is it

^ For a mold blank insert? about $500.
Plastic molds are cheap, if there simple two peice inserts.

It is when you get into 3 or more peice molds, does it get very expensive.
It is all about design and CNC time, which I am doing for free.

We use MUD systems on all our injection machines
http://www.masterunitdie.com/

I ment the final "Low Cost Flow Meter"
how much is low cost...

If it is around $50 or less and works decent I will buy at least 2.

I was hoping for the neighborhood of $20 - doesn't need to be uber accurate.

As far as the guy on wizd's project - the boards hes making also work on the paddle sensors that have larger (3/8") barbs. The circuit (which is an optical sensor, not like the innovatek products which are AFAIK mechanical) can be used on any paddle wheel based meter.

if it is $20 or less I will buy 5.

Ditto. that's about how many I'd need.... well... 1 for 1/2" and then 4 for 6mm ID.

If DD is going to b the reseller then there is no way they will be under $40 IMO though. Maybe we can get them directy from Dave for less?

Read the page I linked you to - Innovatek's aren't mechanical, they're IR, and their "available separately" control board used to convert a flow indicator into a flowmeter can also be added to any paddle wheel.

One nice thing about paddle wheel flowmeters is that they're like a good old fashioned 'visual flow indicator' : walk into a room, take a quick or lazy glance that a-way, and feel reassured. Ones with clear plasic or glass on both sides of the rotor let you mount an LED behind them so you can do this in the dark.

If you can take the face off to remove a stray string of teflon tape or whatnot without having to pull it from the loop, that can be convenient too.

Plastics like nylon that can soak up surficants, antioxidants, anticorrosives, whatnot beyond my chemistry / materials testing are a bummer.

Is there a reliable spec. for the bottom end of pulses / sec. that an hypothetical generic fan header should be expected to sense? ( I have a gems rota-flow installed on one old MB that can't sense as slow as the flowmeter signals; it's a fanles / silent rig that could get by on 0.5 lpm. )

Tangent: I'd write off designing a flowmeter around producing an off the shelf correlation between 4-20 mA pulses / sec and lpm or ml/s or gpm of a particular coolant mix of a particular viscosity with a particular thermal conductivity at a particular temperature and pressure. Like 'low cost flowmeter' on the one hand and the lab kit and skills to establish all that on the other...

I suppose it would be possible to design one that worked in only one flow direction, or was good at trapping bubbles in any but one precise vertical alignment -- that would be sad.

That's what comes to mind this afternoon for someone trying to design / build / sell a low-cost paddle wheel meter for this niche.

Price / performance wise the Swissflow does look interesting, and if it puts out a ball park accurate flow based on a common fan divider, well that is nice indeed.

I'm hoping that being in Canada that i can get them directly from Dave and save myself the customs charges...

It does. It is very accurate, connects straight to a mobo fan header and to get ml/min. you just divide the signal by 6 in MBM. I've been messing about with Samurize a bit more:

http://pic18.picturetrail.com/VOL932.../101207747.jpg
(Temps are a bit high today: 24C ambient room temperature...)

Ideally I'd like a nicely engineered paddle flow meter with a window, LED lighting, accurate IR sensing with a straight conversion of RPM to litres/min flow (or GPM, depending on the flick of a switch or jumper), and integrated temperature sensor. Even better if the thing doubles as an airtrap/reservoir. Even better still if you could bolt it straight onto a pump like the Laing DCC or D5.

We can but dream... but since I'm planning a new project and I know someone with amazing CNC skills, I think I may start designing something myself...

Digiflow 8000T
 

I just recieved one ($59+shipping). It looks to be an excellent piece. Hooked it up to an Eheim 1048, resevour and radiator and it read 0.48gpm. It has a totalizer and a timer. It appears to be rather restrictive. It is about 3/8" at the narrowest where the impeller is located.

You guys might want to check out my thread at:
http://www.wizdforums.co.uk/showthread.php?t=1786

I designed one (complete with schematics) for about $50.

It plugs into a Fan connector (3pin) on a motherboard and delivers flowrate as a function of RPM.

Complete with a calibration profile.

John

No disrespect intended for my second post here. Defending myself here.

IMHO; The problem with the Innovatek is:

1) You can't get it ANYWHERE in the USA reliably.
Yes. HighspeedPC sells them; but when I started my project; they had been out of stock for 3mths. They got them instock after my first prototype was already complete.

2) $55 for a flow meter isn't exactly cheap when you can't get them when you need/want them.

3) It can't be easily customized. OR at least it isn't obvious how easy it is to mod it.
My design can be customized any way you like. If you like the bling:bling mod capability; then you'll enjoy the fact that my design will have your choice LED colors - whatever you want to buy.

4) All the documentation of Innovetek is in German.
I didn't see them providing calibration curves for the device either.

5) Can you really argue with a device that is the size of a US Quarter?

If you don't like my design; that's fine.

I just wanted you to understand WHY I did it.

John

Don't fret, zittwaredotcom. The fact of the matter is that you and I have our exact l/min. (and gpm, respectively) flow right there on our desktops, while the people who criticise are still agonising over how to achieve this... :D

it is a nice flow meter system unfortuatly it is has big hit in the flow.
people running 1/2" ID like myself find it to restrictive

I think the flow restriction on these is not nearly as great as people think (I mean, think about it...).

People often think that they are achieving the flowrates that their pump is capable of, but the reality is that by the time you add blocks and tubing this has gone down to 25%. Most people's system does not flow as fast as they think it does.

I also suspect that flow is, well, a bit overrated. I have 1.7 l/min (which I know for a fact). Yet this happily cools two Opteron 250s (2x85W) plus a Radeon 9800 (50W) on a single BIX, fanned by a low-flow Panaflo. The temps you see a few posts up were at an ambient room temp of 25C. Currently (at 21C) I get 45C and 43C for the CPUs and 28C for the system.