New Mill , Has anybody got one Warco WM-14.

[HS93]

Has I have recently Purchased a WM-14 mill from warco , it should fit my needs as I have great diificulty lifting my arms, I have started to Machine a conversion of the Z way to stepper driven so I dont have to lift my hands to far, I would also Like to convert my fine feed the same was as Ralph (Divided he ad) But I am going to use a small stepper so I wont have to use a gear box and with the aid of a larger handle I should be able to turn it by hand as well. I am also going to do a mod on the small knob that engages the fine feed as it is a small knurled nut and since my last bad flare up om my ilness I have problems with small items and holding parts, I have done a few little jobs on it , made the plate for stepper and a few other bits and the mill works well, quite quiet but would like to get some info on how I oil/grease the gears etc. so if anybody has a nice circuite to operate a stepper motor simply with a few switches I would be gratfull I can build things like that ( or could and think it should not be a Problem)  so any designes wold be great and i will not  pester for help

Peter

will post some pictures of the mill as soon as I can

[Bluechip]

Hi Peter

One very simple Stepper Driver I have built is here:

http://www.aaroncake.net/Circuits/stepper.asp:

Does have it's limitations, but it works fine so long as you don't want it to run very fast.

( I used MOSFETs as drivers, not bi-polar as shown. )

Otherwise the output FETs get damned hot.

( Lack of drive from the CMOS chips, hangs about too long in transition ).

Dave BC

[picclock]

Yup - I've got one. Very happy with it so far.

Fitted DRO's on X and Y Axis. Mine came with a DRO fitted on the spindle.

If you ever figure out a way to grease the gears let me know - It may be to do with a round plastic window on the right side of the mill head. I can't think what else its there for.  You can grease the motor gear by just taking the top off, but after that it may be a head off job. I needed a new motor on mine about 7 months after purchase. Tripped out the house mains when turned on.  Their policy is if its up to 6 months they will visit and fix on site but I was just out of on site warranty, so they just supply the parts and you fit them. Motor gets quite hot when running at high speed, so I leave the top metal cover off if I have a lot of that to do.

Re stepper driver - just my opinion. Use a 19-24V scrap laptop supply. Buy a stepper driver - its less painful. I have made several but for speed and ease of use, ebay. The stepper driver will need two signals. One for direction and one for step. Lots of simple control circuits on the internet. PM me if you get stuck or use the CNC forum on HMEM. Use a 5v regulator from the 24v for the stepper driver signal generator supply.

@ Bluechip
Not sure how to put this tactfully - so please don't be offended. The circuit you posted has no current limit for the motor windings so that the limit is set by the output devices, the winding resistance and the power supply current. Integrated drivers limit the winding current by turning on and off at a high frequency, using the reactance of the motor inductance to maintain a constant current in the windings.
This also allows the motor to run at much higher speeds. It may be that the circuit is for a special type of stepper motor, but its not for the normal types used. Typical stepper motor winding resistances vary from 0.5 to 3 ohms with maximum currents of 2-4 Amps or so. With a 12V supply and no current limit you are likely exceeding the motor current limit (driving with DC, current = voltage/resistance).

Apologies for any offence caused.

Best Regards

picclock

[HS93]

picclock I have half a dozen driver cards I just need a way of controling one without a pc I have a laptop supply I was going to use if you could just knock up a way of controling the driver board I will be able to build it of your sketch/drawring.

Peter

[Bluechip]

Hi Picclock

Nope, not offended. You'll have to do better than that to offend me ..  

I did point out it had it's limitations.

I have used it with a 12V/400mA per phase/ 7.5 deg stepper. No limiter resistors and it works fine unless you want more than 20 or so rpm.

Then the ( STP36NF06L ?? IIRC) Mosfets warm up.

Never tried it with the uChip MOSFET drivers, it would probably be a lot better.

It's a simple driver for basic applications. Probably cheaper than a L297 - L298 set up if you're running bi-polar ..  

Dave BC

[djc]

...I have half a dozen driver cards I just need a way of controling one without a pc...

If you have the stepper driver, use a simple circuit with a 555 timer controlled by a potentiometer to put the step pulses in (e.g http://www.kpsec.freeuk.com/555timer.htm#astable). A three-way switch (FOR-OFF-REV) will do the direction.

[picclock]

Hi Peter

Probably simplest circuit is to use a 555 timer with a pot to control speed, and a switch to determine direction.  So you could use a pot with a switch to control the speed of movement and turn it on and off, with a separate switch for up and down.

If that meets your requirements I'll post a circuit for you. Including the regulator it will probably be about 10 components.

Let me know.

Best Regards

picclock

[HS93]

that would be great ,if you could do that for me.

Thanks

Peter

[krv3000]

o I long for a mill

[picclock]

Hi Peter

Circuit attached.

Have fun.

Best Regards

picclock

[HS93]

thank you for that just one question how do I go in reverse and what controle will I get with it

thank you again for your help

Peter

[picclock]

Hi Peter
The direction of travel is changed with the switch, SW1. This simply sets the driver up/down counter changing direction.

Not sure what you mean by what control. With the pot, VR1 in the off position no pulses are supplied to the stepper driver. When the pot is rotated, the pot switch makes and pulses at a low frequency around 120 Hz) are produced. As the pot is turned the frequency of pulses increases to around 12KHz.

So you get to control the speed over a ratio of 100 to 1. You can change the frequency by altering the size of the capacitor C3 if you need to.

Hope this helps

Best Regards

picclock 

[HS93]

No that's great. that will be supper for the z way on the mill will build it tonight.

Peter

[SamJo]

If you ever figure out a way to grease the gears let me know - It may be to do with a round plastic window on the right side of the mill head. I can't think what else its there for.  You can grease the motor gear by just taking the top off, but after that it may be a head off job.

Never seen a live Warco WM 14 but it looks like another member of the Optimum / Weiss family, size BF 16. On that mill you can lubricate the gears without removing the head. First you'll need to unscrew the head pivot and guide bolts a little so you can tilt the head some 90 degrees. Then you will get access to a cover plate held by four screws. Just remove the plate and take out your grease gun. Easy enough, but afterwards there's the nuisance of tramming the head, again.

Hope this applies to the WM 14 as well.

Jouko

[picclock]

Hi Jouko

There is no plate underneath the head on mine, but it may be that removing the panel on the front of the head will get some access.

It's something I probably ought to do soon - or at least check the state of things.

Best Regards

picclock

[SamJo]

Hi picclock,

I'm sorry it didn't work out. On the BF 16 mill the gear cover plate is in the back of the head towards the column, facing the z axis slide and I assumed the WM 14 is built in a similar way. The front panel on the BF 16 is just fastened to the casting, no openings underneath. There's no quill fine feed or DRO on that mill so the head construction may be totally different after all.

Regards
Jouko

[John Swift]

Hi Peter ,

how are you doing with the stepper drive circuit ????


It looks like your looking for some thing like the test circuit I need to build
but with limit switches added

I've added a modified version of my circuit and Picclock's "555" circuit just to give you some ideas


    John