The illusive Boxford 260vmc

[Ricardoco]

Well it may be ugly but its better than the ones available over here, i found loads of people asking for a circuit to do this but not many links to sites, I cant imagine there is no demand for this type of product, in fact reading the manual for the Texon they even provide a printable overley for your convienience.
There are plenty of people such as yourself who can do a little pic circuit with output to a display of some description and the maths is not too difficult for the program 50pulses=1rev for just a counter, introduce a clock and you have a tacho (not that simple i know) but it is for those people such as yourself and myself for that matter but an off the shelf solution would be better for the masses.

[Wobblybootie]

Yet again I am gobsmacked by the range of knowledge and skills displayed here on the Forum. For the short time I have been a member here I cannot remember a problem that has not been solved in some way or another.

[Ricardoco]

Oh cool the postman has just dropped of some goodies for my collection



12 Relay board DPDT...made by me
27 Switches SPST latching and non latching...fleabay
2 x 0-27vdc power supply boards...maplin
Motor Speed interface for mach...cncdoctor
Opto breakout board...cncdoctor
Standard breakboard...from the shed
50 x bc547 transistors ....fleabay
100 3k3 resistors..... fleabay
100 bi-colour LED's...from shed
100 Chrome LED panel mounts... from shed


and so it begins........

Hey wobblybootie that a cool avatar!!!!

Rick

[z3t4]

Les Jones posted this, first on the Shumatech site, then on MEW.

It works very nicely as a tachometer. I used an Allegro gear tooth sensor and just told it to count 65 teeth per rev.

HTH,

John

[Ricardoco]

Les Jones posted this, first on the Shumatech site, then on MEW.

It works very nicely as a tachometer. I used an Allegro gear tooth sensor and just told it to count 65 teeth per rev.

HTH,

John

Thank you for the link, This looks like a very nice circuit. I was rather trying to avoid digging out the pic programmer and all the other gumph that goes with it. But unless i can get an off the shelf solution, that seems to be the way i will have to go, as both yourself and Irving have indicated.

Ive just moved home and that stuff formed the least important box when moving, which I suspect means it is in the most awkward place in the garage under god knows what.... HELPPPPPPPPP...

[irving2008]

no probs rick... write the code and i'll program a PIC for you... if I havent done it first myself... lol what's your preferred flavour of PIC?

The Les Jones solution is neat, but limited... the Trexon's ability to display Surface Speed based on diameter is useful

[Ricardoco]

no probs rick... write the code and i'll program a PIC for you... if I havent done it first myself... lol what's your preferred flavour of PIC?

The Les Jones solution is neat, but limited... the Trexon's ability to display Surface Speed based on diameter is useful

Ok irving can you explain that a little for me because im missing something here..lol

Ive always liked the 16f877 in the pdip package

What features would it be usefull for this program to have and why?

[z3t4]

The Les Jones solution is neat, but limited... the Trexon's ability to display Surface Speed based on diameter is useful

Admittedly. I think he designed it as a simple tach, but (with an eye on the clever stuff Shumatech can do with a 1 pulse per rev input, e.g. surface speed) I emailed Les and he kindly provided code to produce a 1 pulse per rev output as well as the 7-seg display. A gentleman.

John

[irving2008]

what are you missing? design the program and write the code and send me the source and I'll compile it into a PIC :), sell it on ebay... next stop, world domination!!!

Seriously, I use the F877 in my testbed, which has a 4x4 keypad and a 20x2 display (actually 2, one a serial i/f VFD and the other a parallel LCD).

I would have the program have 3 modes:

Mode 1/ show actual speed in RPM (allowing input of a # pulses/rev value)
Mode 2/ Given a material type & a tool diameter & # flutes (or for a lathe, material type and diameter) and return the recommended spindle speed and feed rate
Mode 3/ Given a tool diameter and current speed show the surface cutting speed in m/min

[Ricardoco]

what are you missing? design the program and write the code and send me the source and I'll compile it into a PIC :), sell it on ebay... next stop, world domination!!!

Seriously, I use the F877 in my testbed, which has a 4x4 keypad and a 20x2 display (actually 2, one a serial i/f VFD and the other a parallel LCD).

I would have the program have 3 modes:

Mode 1/ show actual speed in RPM (allowing input of a # pulses/rev value)
Mode 2/ Given a material type & a tool diameter & # flutes (or for a lathe, material type and diameter) and return the recommended spindle speed and feed rate
Mode 3/ Given a tool diameter and current speed show the surface cutting speed in m/min

Thats a cool idea, in fact i wanted to put some axis jog buttons on the front panel as well so maybe i should consider a pic circuit based control panel along with the speed controller, im ok with writing the program i think (ive spent many a wee small hour with my copy of pic basic pro and a 16f877) but im not sure what the input format would be from the speed pickup and the output to the drivers, this is where my knowlege is lacking im afraid.

and thats not to mention how to do an interface that wont mess up Mach short of having a switch that swapped out all the lines lol. so if we are going down the DIY road im going to need to pick many brains!!!!