What Have You Done To Your Tdm Today?

[fixitsan]

@JBX & Spike240 If/when finished and working as intended, all will be revealed with photos, full component listing/source & wiring diagram.

 

Fixitsan - those dosing pumps look good and may become part of the final system - I chose the windscreen washer pump as I guesstimated it would have enough power to pull the different grades of Scottoil from my >750ml reservoir, would be reliable/endurable and I had a tiny PWM laid idle in the tricks box to control pump speed.

 

 

you should be fine eh. Not sure if a washer pump could self prime with oil, they're often just a centrifugal pump with a large internal vane clearance, but because they're usually mounted at the lowest level of the wash bottle they water usually floods them straight away  But, priming it isn't difficult, just suck on the exit tube ...usual  health and safety precautions, always wear yer wellies

 

Peristaltic pumps can operate with a wide range of fluid level 'head', they self prime, they prevent flow in either direction when the power is off  (self closing) and can provide accurate small volumes if required. .... if you do decide to go down that route the best tube material is 'Tygon' which is inert to most oils, acids etc etc .... other oil resistant types are available, I think silicon will also cope with oil reasonable well

 

We use them on printing machines which I work on, with very nasty inks, which need to be circulated around in precise amounts. Through the first 80% of their life they often dose accurately based on the length of time they run for, but after that the tube inside flattens a bit and doesn't hold the same volume as a new one. I just replace the ink tube inside when that happens, and some of the ones I saw on ebay have replacement tubes so you should get plenty of use for years. Tygon tubes are often rated for 1000hours of use before flattening out too much. The only types of failure are motor burnouts (some thick inks are difficult to pump) and splits in the tube, which happens when the last engineer was a lazy mong....

This post was last modified: 26-05-2018, 10:48 AM by fixitsan.