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Re: G4003G Conversion

Posted: Wed Dec 18, 2013 9:01 am
by Dave_C
CTWO,

Yes, the fins will be upright as in the first picture. ALso, the air inlet into the cabinet is directly below those fins so the air flow is up from the bottom and out the top left side.

It should cool nicely even thought these servos pull 6.8 amps each. That is the reason for that big honkin power supply.

Thanks,

Dave C.

Re: G4003G Conversion

Posted: Sun Dec 29, 2013 10:50 am
by Dave_C
Ok, the CNC Motion Panel is just about complete. I still need to install the 5 VDC regulator for the spindle index but the cabinet is mounted and the backplane has been installed with all the electronics mounted on it.

You can't tell from the picture but the panel is installed on the wall just above the splash guard on the lathe. In small shops you have to put them where you can get to them and this seems to work out for me.

My three phase motor is on the way and when it gets here I could go ahead and use the variable speed part even though I don't have the Ballscrews and bearings yet.

Speaking of bearings, those of you who have done a conversion succesfully, what bearing spec did you use. The reason I ask is that I can buy a double bearing for the fixed end of the ballscrews but the specs say "C7" and that seems pretty poor to me.

I've got all the elcectronics worked out but now I have to work out all the mechanical stuff. (Ballscrews, bearings, limits and mounting plates)

Life goes on and I'll be back with more pics once I get satisfied with the mechanical design.

I suspect it to be a while.

Dave C.

Re: G4003G Conversion

Posted: Wed Jan 08, 2014 5:02 pm
by Dave_C
Guy and Gals,

Once in a while I run across a firm that has excellent customer service. When I do, I like to share it with everyone else so they can benifit as I have.

I ordered a D90L (Metric IEC) motor for my CNC project to replace the 2 HP single phase motor I have now. It was supposed to arrive via FEDX on January 2nd but arrived January 8th instead. I called FEDX and they had an excuss every day so I emailed the company from whom I bought the motor. I got an email the very next morning with a very positive repsonse and then a follow up phone call the same day.

Ed did an outstanding job of following up with FEDX and getting my motor to me. He even offered to ship me a replacement 2nd day air. Now that is not cheap for a motor that weighs 42 pounds!

On top of that, he refunded my shipping charge of $29.00 (which is low for 42#s) and then called the second time to check and see if the motor arrived without damage.

I bought from them because they had the best price of $208.00 (US) for a 3ph 2 HP 87% efficient inverter duty motor.

I think this company would be a good source for any of our motor needs, even Metric ones!

I would call him direct if you need something you can't find.

Edward Frye

Electric Motor Wholesale.com
829 Lion Hope Road
Clayton, DE 19938

(302) 653-1844 ext 11 phone

(302) 223-6247 fax

sales@electricmotorwholesale.com

Tech Support 11 & 14

Sales ext 12

Accounting ext 13

Vendors that go to great lengths to take care of us deserve some praise. I suppose those who perform poorly deserve some attention as well so we can avoid them.

This was a good one!
Dave C.

Re: G4003G Conversion

Posted: Wed Jan 08, 2014 6:45 pm
by ctwo
Good deal Dave. Proof the old American spirit still lives. Very nice job on the panel. I am far too lazy for such perfection.

Re: G4003G Conversion

Posted: Mon Jan 20, 2014 11:08 am
by Dave_C
Greetings again:

Some progress, this time on the computer and monitor stand. Due to space restraints around the lathe, I decided to make a stand that I can roll around as needed. The arm that holds the keyboard tray and monitor pulls in and out as needed and the whole arm can be lowered to a sitting position by loosening the four bolts on the back clamp. As pictured it is in the standing position like it would be if I were standing at the lathe. Being right handed I prefer the keyboard and screen on the right instead of up around the head stock.

I do have some good news on the Z axis ballscrew and nut. Automation 4 less has 5 overstock screws that are 50.375" long and have zero backlash nuts. These are NSK "precision ground" ballscrews with .0005" +/- runout per foot. Normally these are $1,300 each. They are offering them for $300.00 each. (25MM diameter with 4mm lead) The lead is a little fine but I can change my micro steps if I need more speed.

50.50" was my target for ballscrew length so this should work.

Edit 02-25-14 (Ball screw did not work out due to the ends being turned down to small)

Here are a few pics of the stand.

Dave C.

Re: G4003G Conversion

Posted: Mon Jan 20, 2014 11:47 am
by Dave_C
Update on the Ball Screw and Nut.

Once I got the drawings from Kent at Automation4Less.com I could see I was not going to be able to use them. The ends had been turned down smaller than the proper bearing size for this screw. 12.70 MM on the free end and 14.60 MM on the fixed end. They suggested making a sleeve but it would have to be welded in place to hold the thrust force on the Z axis.

I still give Kent high praise for being helpfull as none of the other ball screw companies have even tried to help.

Back to the drawing board!

Dave C.

Re: G4003G Conversion

Posted: Tue Feb 25, 2014 12:07 pm
by Dave_C
Progress:

I finished boring the timing pulleys for the Servos and the ball screws.

For those who are keeping track of the parts, these are 26 tooth pulleys and made for 5mm pitch round tooth belts that are 15mm wide. OD Flange diameter is roughly 1.75" This looks like it is the perfect setup as the 26 tooth pulleys in this size leave ample room for the boring and set screws.

I used 10-32 x 3/16" setscrews in the .500" bores that have 3/16" keys and I used 8-32 x 1/4" in the smaller bores that had 1/8" keys.

The pictures of the belts are ones I ordered in 4",5",6" & 7" centers as I don't know yet what the exact center dimensions will be. They are pretty cheap and it was easier to get extras than to pay the freight on a new order. Belts and pulleys bought from Polybelt.com.

Re: G4003G Conversion

Posted: Tue Feb 25, 2014 12:11 pm
by Dave_C
I should have put some of this within this topic but I got off on another thread regarding the turning of the ballscrew ends.

Hopefully this link will take you to that thread: http://www.chaski.org/homemachinist/vie ... =9&t=98353

Dave C.

Re: G4003G Conversion

Posted: Tue Feb 25, 2014 1:41 pm
by FLSTEAM
DrDavo

Where did you get the computer stand? Looks nice and heavy and just perfect to mount on the back of my roll around tool box.

John B.

Re: G4003G Conversion

Posted: Tue Feb 25, 2014 2:05 pm
by Dave_C
John B.

The top part that holds the monitor and keyboard, and has the adjustable arm, was purchased off of Ebay. It was the only version I could find at the time.

The bottom part (Grey steel, with the wheels) I made myself and clamped the above part to the upright post.

There are different models from time to time on Ebay. You'll just have to search till you find what you need.

Dave C.

Re: G4003G Conversion

Posted: Wed Mar 19, 2014 11:29 am
by Dave_C
Progress Continues:

I just finished the Preloaded ball nut set up for the Z axis.

I tried to take some pictures but they need explanations. In the first picture I laid out the parts in the order that they go together.
Parts Layout
Parts Layout
In the second picture the view is just from the other side.
Right Hand View
Right Hand View
In the third picture the parts are assembled. The dog point screws are not set into the slots in the adjustable tension hub and won't be till this thing is on the ball screw.
Assembled
Assembled
The square block is the thrust block that will attach to the plate that moves the carriage. The double row ball nut is threaded into this block and held in place from turning by three set screws.

The single row ball nut is threaded into the thrust collar which has 6 slots each are 60 degrees apart giving me the ability to change the preload by 1/6 of a turn on a 18 pitch thread. The thrust block has three dog point set screws 120 degrees apart. They are left out till the assembly is tightened and then when in place will allow the thrust block to move back and forth on the spring washer.

The movement required is not great but necessary to allow for any drunkenness of the thread. Making these fixed without any movement is not a good idea as they will bind and wear out.

The spring washer has 230# of pressure at contact and 400# if pressed flat. It has about .028" of travel which is way more than needed.

I think it will serve my needs very well.

Dave C.

Re: G4003G Conversion

Posted: Wed Mar 19, 2014 11:40 am
by Dave_C
I attached the drawing that I made. It may be a bit hard to read at this low quality but ask if you have questions, I'll be glad to help if I can.

Dave C.