Build Thread: Upgrading EMCO Compact 5 CNC to current technology

[KnacK]

I figured I would go ahead and start a build thread.

I recently purchased a gently used Compact 5 CNC that was at a tech school. The machine appears to have seen little use and I discovered why: The push buttons and switches appear to have corrosion on the contacts over years of no use, so trying to use it, let alone program it, would be very difficult.

Link to current pictures of lathe: EMCO Compact 5 CNC Lathe



The machine has a lot of dust and a bit of surface rust, nothing that can't be cleaned up easily. Taking of the rear cover was a shock: You could eat out of it:

The overall goal of this upgrade is to make this as user friendly as possible. I am not a practicing machinist but I understand the concepts involved. Plus where I work, I have a few seasoned veterans that are willing to guide me into my new endeavor learning G-Code and machining principles.

Before purchasing the lathe, I had been doing a lot of reading. Between here, the EMC web site, Artsoft, Hobbycnc, and CNC4PC I've learned a lot.

So here's a breakdown of what I want to accomplish:

1. Replace existing steppers with newer steppers that are a bit more powerful. It appears the current NEMA 23 steppers are 60 oz, 9v and about 2 amps. I have some 100oz steppers that I picked up for a song that I should be getting any day now.
2. Completely bypass existing electronics to be able to use a stand alone dedicated pc to run the lathe.
3. Clean and paint lathe to make it more presentable.
4. As it did not come with any tooling, I am exploring QC tool change posts from Little Machine Shop in probably the AXA size. Still unsure exactly what will fit though. Maybe this Quick Change Tool Post Set by A2Z CNC
5. Would love to find an automatic tool changer to use.
6. Mach3 or EMC2 - Big decision there.

So far Here's where I am leaning for electronics:

1. Per Arturo's suggestions at CNC4PC I will be using a HobbyCNC PRO Chopper Driver Board Kit
2. probably a C11 - Multifunction CNC Board
3. A C3 - Index Pulse Card for spindle speed control.
4. Try to utilize existing power supply for stepper power if at all possible.

So, as you can see I think from the conversion aspect I almost have all of my ducks in a row. Currently the only thing that a bit blurry will be the spindle speed/direction control.

As I side note: I was going to post the build over in the Yahoo group for this lathe, but since you have to join the group and search engines don't search the group, posting here will get more exposure and hopefully help more people out.

I also take constructive criticism pretty well so if you see a direction that I should be looking into, post up.

Thanks

[KnacK]

I went ahead and ordered the HobbyCNC Pro Chopper board today:


I should be receiving my 100oz steppers and the driver board about the same time.

I found a really nice pdf download on Gecko's web site that talks about steppers and the various configurations, torque vs. speed, and power supply design and requirements. Quite a good read:
Stepper Motor Basics Guide.
Plus there are a lot of other interesting white sheets on there as well:
Application Notes and Manuals

[samco]

Looks like your spindle encoder is a+z? (single channel encoder plus Index)? Looks to be about 200ppr?

http://picasaweb.google.com/cmuncy/E...40045475520578

With emc - you could use both channels to get very accurate threading. (instead of just the index pulse once per rev)

If you added another channel (a,b,z) you could do rigid tapping - (if you can reverse the spindle though the cnc)

sam

[KnacK]

That would be the ultimate goal sam. I didn't count but I would guess that it is 200 indexes plus the one notch. I should have enough I/O to get the signals back into EMC or Mach3 whichever I decide.

All of the tech is there, making it work is the fun part.

[KnacK]

Just ordered a C11 breakout board from CNC4PC today. Now all I need to do is build a power supply or use the existing EMCO power supply and I should be able to get this thing spinning under pc control in a few weeks.

[KnacK]

w00t!

Got my C11 board from CNC4PC today! I need to see if Fry's carries any bridge rectifiers. If not, time to go to Electronic Parts Outlet down in the Galleria next week.

Other than the power supply, I need some sheet metal to and stand offs to mount the 2 circuit boards to. Timing could not have been better on the delivery of these.

[dfstrasser]

How's the retrofit coming? Any more details?

[KnacK]

Not as much as I would have hoped.

My HobbyCNC board is built and tested.
I have all of the parts for the power supply.
I have a pc all set and ready to run both Mach3 and EMC2 depending on what I like better.
Now I need some free time.

I am still needing a tool post holder and some tools to go with it. So if someone knows of a good off-the-shelf tool post for this lathe that would be great.

Thanks for asking about the status.

[dfstrasser]

I'm looking to do the same thing real soon. What are your plans for the spindle motor?

[KnacK]

Spindle motor will remain for now. It has plenty of power for the size machine that it is.

I have thought about getting some sort of vfd for doing constant surface speed machining but that's lower on the list of things to do.

[Marty_Escarcega]

Spindle motor will remain for now. It has plenty of power for the size machine that it is.

I have thought about getting some sort of vfd for doing constant surface speed machining but that's lower on the list of things to do.

Do you have the DC spindle motor and how do you plan on running it?
Do you have any old CNC5 control parts leftover?
PM me if you do.
Thanks
Marty

[mrmeng]

I am looking to do the same thing with a EMCO Compact 5. I would like to ask you a few questions if you don"t mind?

As the machine is built (before conversion) by EMCO can it use G-code?

In the conversion do you control the speed of the spindle as "on and off" in the program and manually set the rpm outside the program?

Is that a tape reader on the panel?

Do the motors use standard screw hole locations? Can another motor be placed in the existing mounts?

You can pick up a EMCO Compact 5 tool changer on Ebay for about $250. It seems they rotate so many degrees and then go back a few degrees and lock in, just like a 4th axis.

Mike