The 'ultimate rev counter' thread...

[irving2008]

Certainly a lot more professional and easy to use than my 1st pic board :whistling:

Attachment 2628

lol don't knock stripboard, it has its place... I use plugboards now for prototyping (pic is my basic setup) but for some things where you want a copper ground plane, stripboard still works bette as a prototyping medium...

[ecat]

Heh, general dev board looks a little different these days



and prototyping a little more advanced



That's a few Dallas temperature sensors, 80MHz cpu board, 32K external RAM, 4MB external flash and a 1GB micro SD card. Add a little test software (http://forum.sparkfun.com/viewtopic.php?f=19&t=17217) and things have come a long way :)

[irving2008]

Now you're just showing off lol

[ecat]

<chuckle>
I know feck all about mechanics so I've got to find some way to justify my membership here ;-)

[Wobblybootie]

<chuckle>
I know feck all about mechanics so I've got to find some way to justify my membership here ;-)

Ruddy Hell ... I know sod all about anything useful to this Forum, I just soak up stuff, except anything mathematical :confused: [sorry Irving] ... so I shall beat a hasty retreat (aka Tactical Withdraw) to my little Sanger and keep a listening watch!!:whistling:

[GeorgeD]

Tsk! it was one of these when I wus a lad...
http://www.tvfilmprops.co.uk/userdata/PRODPIC-914.jpg

[z3t4]

I hadn't used stripboard for ages until I made Les's Tacho x2. Much more used to the joys of UV boxes, FeCl3 etc. I have now resolved never to use stripboard again. It's just too much hassle checking for shorts between the strips :sad:

ecat's Eagle .brd looks good. Must investigate ...

Just a thought about the design spec. Three features of Les's design that I really liked were

• the use of the Allegro gear sensor (it's as good as gold; no messing with slotted discs/foil/Tipp-Ex etc, very reliable, very robust -- just needs to be mounted tangentially 1-2mm from teeth)
• the capacity to accommodate a non-standard number of pulses per rev (65 in the case of the ml7 bullwheel)
• a one pulse per rev output (useful for my Shumatech DRO's).

HTH

John

[irving2008]

I hadn't used stripboard for ages until I made Les's Tacho x2. Much more used to the joys of UV boxes, FeCl3 etc. I have now resolved never to use stripboard again. It's just too much hassle checking for shorts between the strips :sad:

ecat's Eagle .brd looks good. Must investigate ...

Just a thought about the design spec. Three features of Les's design that I really liked were

• the use of the Allegro gear sensor (it's as good as gold; no messing with slotted discs/foil/Tipp-Ex etc, very reliable, very robust -- just needs to be mounted tangentially 1-2mm from teeth)
• the capacity to accommodate a non-standard number of pulses per rev (65 in the case of the ml7 bullwheel)
• a one pulse per rev output (useful for my Shumatech DRO's).

HTH

John

All of which are on my list... I started looking at how to fit to my minilathe and quickly decided a slotted disc wasnt going to fly (or should that be 'rotate'?) Since we have some fixed gears, clearly a reluctance sensor is the way to go, so started looking for something suitable..

The software design already accommodates a 'divide by N' feature as Rick needs /50 for his, and I will need something for the minilathe and if I do one for the mill too Im sure that'll have a different value. I haven't yet decided how to set this.. probably a jumper and a push button... at power up if jumper present go into setup mode and each press of the button increments the 'divide by count' from 1 to 100, hold it down 5sec is increment by 10... release button for 10sec, store in eeprom

One pulse per rev is easy...

[GeorgeD]

Irving,there is a way to mount a disc on the lathe...

One disc with a hole in it and mount it on the back of the spindle just behind the two locknuts,you'll have to make a short arm piece of metal for the slotted sensor to fit over the disc.
This way its covered up and out of sight.

[irving2008]

yes, but I want more than one pulse/rev... for closed loop speed control you can't have too much information... and a sensor on the fixed gears may well be easier...

Note: if anyone reading this has a minilathe with built in rev counter... how is it done? Are there any useful parts that could be acquired as spares? I had a quicl browse for a parts list online but all of the ones I found don't detail the rev counter...