[phomann]

Peter, I did try the board i got from you on the mill. I was going to contact you about it when I got the chance. I couldn't get it to work. It may actually be my motor controller that isn't compatible.

This is my motor controller. I am running it on 220 VAC and it is mounted on the required heat sink. My motor is a 2 wire brushed 180 VDC 2.5 HP max. The controller maxes out for 2 HP. These two items work great together. The trouble starts when I want Mach to control them.

I think the conflict between this controller and your board is because this controller says I can't hook up S3 for use as a voltage follower. Page 23 in the pdf here.

The control voltage range on 220 VAC is also only 0 to 2.8 VDC. I think therein is the incompatability with the DC-06.

Then again, without a wiring diagram, I can only tread water. Any help or thoughts there would be great. Thanks.

Hi Lee,

OK, I had a look at the manual and we should be able to get it to work. I looked at what you ordered, and noticed that you did not order the optional dc to dc converter. You will need this as the drive does not produce enough voltage to drive the DC-06.

Also, can you tell me what rev board the dc-06 is? It will be on the PCB.

What I want to do is send you a new one with the optional converter installed. The Rev:3 boards have the adjustment pot so that you can reduce the output voltage down to provide a max of 2.8V

Once you get the new one working, you can send the original one back.

Cheers,

Peter.

[LeeWay]

I didn't get a chance to take a peak at it today as I intended. Forgot it actually. I'll look tomorrow. I think it does have a pot on board though. I was also using a clean 5 VDC supply from a wall wart.

Send me what you think should work and what you think I might need. I will likely keep this other one to use with this lathe. I'm pretty sure it will work with the other little controller I have for it.

Just send me an invoice through Paypal and I'll pay you for it. No problem.
Thanks a bunch.

[LeeWay]

Peter, here is an image of the DC-06. I think I may know why this wasn't working for me. It may be that 5 VDC connection. I don't think I wired the ground pin on the incoming to the 5 volt -, but to a PP ground pin. However the power light does work as does a relay light. I may require some hand holding on it.

I turned my X screw down on one end so far. Just using some decent flanged pillow blocks for now. There is enough journal turned on these though for a proper double bearing setup later on. This should work fine for awhile though just to get up and running.
Turned the bearing journal down to 1/2". 7/16" 20 on the threads and 3/8" for the motor coupler. I used a belville washer between the nut and bearing. This bearing wasn't a locking collar, but is solid with two set screws. It's nice and rigid.

[phomann]

Peter, here is an image of the DC-06. I think I may know why this wasn't working for me. It may be that 5 VDC connection. I don't think I wired the ground pin on the incoming to the 5 volt -, but to a PP ground pin. However the power light does work as does a relay light. I may

Hi Lee,

Thanks for the image. From the photo, you have the rev:3 board. The only thing missing is the optional DC/DC converter. I'll put one in the mail.

Once you receive it you need to plug it into the empty IC socket, and move the JP2 jumper from the AV+ position to the DC/DC position. You can then revove the red wire from the DC-06 AV+ terminal to the speed controller.

Then, remove the 9-way pluggable connector from the DC-06 board for testing and set-up. With the DC-06 turned on and being driven at full speed from Mach, you will be able to measure about 12V between the AGnd and Vout pins on the DC-06. You can then adjust the VR1 trimpot to reduce the max voltage out to 2.8V.



One thing to check is that the Input logic polarity jumper is in the correct position. From the photo, you have it set to positive logic. That is, a logic 1 from Mach will turn on the relays, and povide positve edge logic to the DC-06. Make sure that Mach is setup the same way. If you have Mach configured to use -Ve logic, then change the JP1 jumper on the DC-06.

Cheers,

Peter.

[LeeWay]

Thanks a bunch, Peter. I think that will clear up my issues. Send me two of those little converters and another DC-06 and I'll pay you for them. I'll shoot you an email to confirm.

[LeeWay]

Okay, Peter.
I received the new stuff. Just added the extra generator chip to this board. Swapped out what needed swapping and regulated it down to 2.8 volts.
Viola!
The speed works perfectly with no loping. The speeds are dead on @ 3000 RPM and 6600 RPM. Within 5 or 6 revs.
At 1000 speed setting, it is like 960. 2000 is like 1980.
4000 is around 4060.
6600 is 6605.
Perfect enough for my mill for sure. I could likely fiddle with the control board to get it even closer, but this is fine. Nice and smooth operation throughout the speeds. Very nice. Thanks a bunch, Peter.
That has plagued me for awhile.
I feel confident that I can do the same for this lathe.

I have made only a little more progress on this. I did manage to powder coat the spindle head and riser. I order the steel plate for the saddle or cross slide base. I'll get a picture or two when I can.

[phomann]

Okay, Peter.
I received the new stuff. Just added the extra generator chip to this board. Swapped out what needed swapping and regulated it down to 2.8 volts.
Viola!
The speed works perfectly with no loping. The speeds are dead on @ 3000 RPM and 6600 RPM. Within 5 or 6 revs.
At 1000 speed setting, it is like 960. 2000 is like 1980.
4000 is around 4060.
6600 is 6605.
Perfect enough for my mill for sure. I could likely fiddle with the control board to get it even closer, but this is fine. Nice and smooth operation throughout the speeds. Very nice. Thanks a bunch, Peter.

Hi Lee,

I'm really glad it solved your problem. It is almost impossible to get an open loop speed control to be spot on all the time as there are all sorts of mechanical issues such as mechanical resistance. etc. The best thing to do is set it up to be spot on at the speeds that are important.

Cheers,

Peter.

[LeeWay]

That is what I was thinking, Peter. This is well within the range for a mill. Maybe even close enough to thread at some speeds.
With my small end mills, (3/16") I use 3000 RPM for steel and 6600 for aluminum. Those speeds are almost prefect.

Now on the lathe, I have an index pulse card. I have to see how it will work, but it should get it close enough to thread on there.
Does this override the DC-06 for threading? Does it work in conjunction? These are questions I will have to find answers to.
Thanks.

[phomann]

Hi Lee,

For threading, Mach measures the spindle speed and adjusts the X feedrate to match the spindle speed. So you set the speed of the spindle to a set value, and Mach3 will match the feedrate to it. The important thing is that the speed stays constant. It is not so important that the actual speed is the same as the set speed, jusyt as long as it doesn't vary.

Cheers,

Peter.

[LeeWay]

Thanks Peter.
I think it will do fine. I did notice that yesterday in the AM, I had a little slower speed than the 3000 or 6600. At night it was back to perfect. My line voltage must vary some.

I know the motor I have for the lathe isn't as strong as the one on the mill. I don't think it has to be. At least not for a small bench top. It's only going to have a 4" chuck.

The motor controller on the mill is real nice with all the adjustments you could want.
There are fewer on the lathe controller, but should suit.
Here is a link to that motor driver.




I have a question about using this one with the DC-06.
This controller won't start at high speed. Will the DC-06 still drive this board?

Will I have to hand code a slow speed initially and then bump it up once running?

Just curious.
Thanks.

[Bubba]

Lee,
I think there used to be some mods to the circuit that would defeat the zero start. I will look around in my stuff to see if I can find it.

[LeeWay]

Sounds good.
Thanks, Bubba.

[rot]

Hello Lee,
nice design. I hope it will be strong enough. A CNC lathe will be one of my next projects after i finished the Zoltar

rene

[Bubba]

Lee,
I couldn't find the information on my hard drives (have had a few crashes over the years so I'm surprised), however, I have found a couple of hints on the net that may help?

"If your controller is similar to mine and you are using a pot to control the speed you can just open the wiper (center lug on the pot) connection. That will stop the motor. When you reconnect it, it will soft start and come up to the speed it was set at"

"The controller usually uses a 10k ohm pot. Most have the safety turn on feature so that the treadmill can't be suddenly turned on at high speed. To make the controller automatically turn on regardless of the pot setting (almost) all you need is to connect a 470uf 16vdc electrolytic capacitor across the pot with the positive lead to the wiper and the negative to the ground.

This will hold the control voltage low enough when first turned on until the capacitor charges to the pot setting that the controller will think it has been turned down. It won't work if the pot is turned all the way up as then the time constant is effectively zero because there is no resistance between the +10dc control voltage and the capacitor. To overcome that a 1000 ohm resistor may be placed between the +10dc pot connector and the hot leg of the pot. This has the effect of reducing the maximum speed by 10% or so but that can be regained on most controllers by adjusting the top speed trim pot on the board.

Putting the capacitor in circuit will also slow the response of the motor to adjustments made to the speed control. It will take a few seconds to stabilize at a new setting but has the advantage of producing a slower ramp up to high rpms if set that way when turned on."

If I find anything else, will post here.

[LeeWay]

Thanks a bunch, Bubba, for your time looking this stuff up. Seems like there will be a few options when the time comes. One of them is bound to work.

[Bubba]

Lee,
finally found the info I was looking for on the http://www.metalworking.com/dropbox/...retired_files/ site.
Attached is a zip file that hope will help you out.

[Jason3]

Hi Lee,

Very many thanks for the big favor recently!

Any progress on this machine lately? I'm having an unwanted break from building machines while we finish off the workshop, so I am hopping around impatiently and avidly reading about everyone's mill and lathe builds... Oh, and gathering parts of course...

Are you still intending to use gang tooling, or do I recall you asking about a turret earlier? I'm puzzling over this myself at the moment, it seems if one wants a nice small turret, one goes out to the shop and builds it.

I guess there's nothing to prevent starting with gang tooling and adding the turret later, just that the cross slide travel could probably be a lot shorter with a turret, thus keeping the machine nicely compact (an advantage to me, as space is likely to become limited quickly!)

Best regards,

Jason

[LeeWay]

Thanks guys.
Not much more progress to report yet. I have been having to work some overtime on my production. I was paying my son by the part for welding up my guards and he just hasn't been able to help much. This slows my production way down and I was already behind estimated time a couple weeks on my products.

Good help is damn hard to find.

This is precisely why I like my CNC machines so much. At times I get all three working while I am using another machine. That is just cool.
They rarely talk back either.

I was considering using a turret eventually, but gang tooling for sure to start with. My parts are really pretty simple. I am using a cross slide table to mount the tools on. I think it's almost 6" by almost 12" or so. Should be plenty of room to gang em up.

I do, however still drool over the parts from time to time.
I will be powder coating all the steel parts. I will even PC the table edges and slots. This should prevent much rusting.
I will have to use special masking tape to mask what doesn't receive the powder. Pain in the trailing end for sure, but low maintenance overall.
PC is a fine machine finish. I can absolutely tell the difference between painted and PC'ed on the mill.
Coolant weakens the paints I have used, but not what I PC'ed. It still looks as good as it did when I pulled it out of the oven.

Don't fret none though. I will be updating this thread as soon as possible.

[LUCKY13]

LeeWay, I noticed they have some 3 & 3 1/2hp treadmill motors at the surplus. I wander if the bigger controller will run one of these. I know you would have to at least go 220v (no problem there) but even with a heat sink the controler only claims to pull 2hp worth of load. I was thinking if a person made a better heat sink and used a good fan system the bigger motors might run on those controllers.


If not, what controler could one get to push those bigger motors ? I would really like to run that 3HP 4100rpm motor on my big mill.


I have my parts gathering up for the CNC conversion. I went with 850 servos,Gecko320's, CNC Brain and Rockford Ball screws. I really need that extra power for my spindle and the RPM also. I could just go for one of the 2 1/2hp motors, I think they have one that has some very nice RPM. A belt drive and this would be sweet. I guess if worse come to worse I could put a encoder on that big motor and run it with a Viper servo drive but thats starts getting into some funds. I have a lot of work to do just to get this thing going, but as far as design and parts my spindle is all thats holding me back.


BTW, a 3rd machine, no wait is that the 4th ? Cool, your mill works so good I think a lathe of this design will rock also. Between you & Hoss (plus many others) you guys are what keeps my motivation up to keep me going with all this. Thanks You.


Jess

[ALWAY]

Leeway,
This is my first post to CNC Zone. I am also contemplating building a mini lathe very similar to yours. This all started back in March 2008. I googled looking for info on linear motion devices to use for each of the axes and ended up here.

Before going to far with the Headstock and Spindle have a look at this site and eBay Item 150312130102

http://www.arceurotrade.co.uk/projec...ges/index.html

I will be using tapered roller bearings as the bearings for the mini lathe headstock casting.

I need a favor from anyone that can measure the mini lathe casting. I need the foot print dimensions to make some detailed drawings for the build.

I did find all the info I needed for the linear motion stuff, here and your mill build thread. What a fantastic example of DIY. You should be very proud of your accomplishement.

Al