[Bloy2004]

I got that kit too from Dan at Camtronics. to fasten the little connectors to the wire I crimped them using a small needlenose pliers and then soldered the crimp. Also, on the servo motor connectors, I removed the female connectors from the red plastic plug and soldered each wire to the connector and then re-inserted the spring clip into the red plug, thus ensuring that the wires wouldn't have a bad connection and cause the motor to "runaway". When I get my lathe running, one of the first projects will be to make a housing for the encoder and plug to firmly hold the wire and protect the encoder from debris from cutting, lubricant and coolant.

[HomeCNC]

I don't have trouble with the connection between the wire and the plug. My problem is with the male and female plug. It will not hold strong. I now use 1/4 turn locking connectors on the controller boxs that I have made. http://www.homecnc.info/Pics/powerbox-front800.jpg
This box was for a CNCZone member.

[DaSigntist]

Howdy Guys,
Here is where I am as of today………

I saw some 600 oz/in Amtek servos on eBay and thought perhaps I should make up my own motion system.
I asked the person who was running the ad (which had great feedback) if he would be interested in making up a gecko driven servo system for me . . .he said he had a 4 week turn around. . . I declined.
He sent me to Dean at Axxus http://www.axxustech.com and I thought if I could let go the $1595.00 USD (plus servos) He’s asking I would do that but….It’s Christmas and I’ve got 5 kids and money can get tight.
So I then decided to wire the whole deal myself and save a few bucks.
When it’s all said and done I’ll post all the numbers as I know how valuable that can be for viewers wondering if this something they want to do.
I won’t have a fancy box to start with but I’ll be running 320 Geckos pushing three 1100 oz in Hathaway servos so it should be VERY powerful.
I also bought cables and a parallel interface from him as well to interface with the Geckos.

Geckos are on order.
2 48V 10 amp Powersupplies have been won on eBay.
They have ajustable voltage so I thought I run them together to get the higher volttage/amperage.
http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3059598209

I did register MACH2 http://www.artofcnc.ca/ so I can play with it in its full version till the goodies arrive.
Art is like lightning with the support and I highly recommend his products as you won’t find anything in the ballpark for the money!

I still have connections to solder for the limit/home switches.

I’m only concerned about my acme 5/8 rod as its too small and it has some minor bends in the 4’ lengths and when I hooked up the MaxNC servos with no load it was ready to vibrated to the point of something falling off ;-)
I might need to upgrade to a larger rod like 1" or so.

Till next update!

[zaboomafoo]

Hello Dasigntist,

Your machine looks similar to the one that I built earlier this year. Here are some of the problems comments that might help you:

From the picture it seems that you have 3/4" shaft on Y axis - my machine is 3' on Y side and I used the same shafts. However once I built it I've noticed that there is a significant flex on the Y line, even on the light cut (in the center area). Even though 3/4" looks strong enough it is not - unless it is supported. To fix this I added two aluminum bars on top and bottom of the gauntry and put some kind of slide made of delrin. That helped. I will try to get a picture of the assembly if you are interested. I also added a "L" shaped bar on the back of Y MDF to make it stronger. I still have some flex on the Z in some cases, will have to fix that.

Since you your machine has 4' wide Y axis you might have problems if you put a single drive for X. it might flex when you cut close to the Y=0 or Y=max. Parallel drive on the X axis would help. On my 3' Y axis I didn't notice that problem.

Acme screws - I am using 1" acme and problem with them is that the general purpose acme screw is far from being straight. I find the precision to be good for the woodworking. Problem is that on 4' lenght any spped over 50 IPM pushes the limits. After I installed a home-made delrin nuts it is a bit better but still 50IPM is the fastest reliable spped I can get on 4' X. on 3' Y I can get 60 IPM.

I am using Xylotex drive and stepper motors that I've purchased from Dan (camtronics) 262oz. Motors ratings are too high for bipolar paralel settings but I am happy with the bipolar series too.

last note - build a CNC from scratch is like buying an old car - there is always something you have to do on it. That is a problem or good thig - depends how you look at it.

Regards,

Frank

[HomeCNC]

I saw some 600 oz/in Amtek servos on eBay and thought perhaps I should make up my own motion system.

Be careful with these motors. If this is the guy that has a ebay name of something with "CNC" in it, his servo motors have an encoder that is not 100% compatable with the Gecko drives. This means that the Gecko will not be able to power the encoder. They would require their own power source.

[balsaman]

I use the +5 volts from the step/dir common to power the encoders, since they draw over to 50 ma. max of the gecko.

Eric

[DaSigntist]

Howdy all,

Zaboomafoo:
I’m using 1” harden steel rod which seen OK but I’ll keep an eye on the flex.
I figured I’ll need to keep the rapid and federates down and then perhaps upgrade when I can spend the bucks for perhaps some high end screws.
I know now if I tried to go full speed I would watch my machine explode ;-)
As I see it I’ll upgrade the weakest link or links after I’m under power.

HomeCNC:
I’m going with 1100 oz/in Surplus Hathaway servos from Axxus with new Digital US encoders.
He knows I’m using 320 Geckos so hopfully it will be OK.

As always thank you for your input!

Happy Thanksgiving!

[balsaman]

Put limits on that bad boy. With 1100 oz-in motors a crash will tear it apart.

Eric

[DaSigntist]

Your reading my mind!
Those brutes will be on the floor still spinning if not contained as it eats the machine alive.
Limit/home switches will be done tonight with wire dangling.
I bought nice small one from Radio Shack 4 for 4.99 CAD in the normally closed position.
I’m trying to have everything that I can do done before the big boys get there next week.
The bummer is it will be about 10 days or more for the Geckos/power supply to arrive.

[balsaman]

why did you end up going with such big motors?

[DaSigntist]

More POWER!!!!!
(Insert the Tim the Tool Man GRUNT here!)

I was just going to do 600 oz/in Amtek servos but Dean at Axxsus offered me the 1100’s at the price of the 600’s.

I also am thinking in the future I will build a steel 4’X8’ machine and will bring the motors over for that.
The two things that I do not want to end up with is a machine that is underpowered and slow.
The power part is under control so now I need to deal with upgrading the acme as soon as Christmas is paid for ;-)

[turmite]

Hey Dasignist have you considered a timing belt drive instead of the screws? I was going to use a precision ball screw but after talking with Mariss from Gecko I am going to use timing belts when I build my machine. I am upgrading my current machine which uses rack and pinion and I have run that one at 1000 ipm once just to see if it would do it. That was using full steps and a slow acceleration but it finally leveled out about the time it had to start ramping back down. I hope the timing belt system is as good or better than the rack and pinion because it has served me well.

turmite

[DaSigntist]

Hi Termite,
I have but I figure that I’ll try the path of least resistance first.
I’m sure I won’t keep my hands off the machine and will always be tweaking and upgrading it trying to make it faster.

I’ll keep an eye on your posts when you get started keep us informed.
I’d love to see photos of your machine.

[BeerFizz]

Hi Dasigntist,

could you post the link where you got your surplus servos?

Thanks alot.

[DaSigntist]

I got them from Dean at www.axxustech.com
Tell him James Brake sent you "oops" now you know who I am (lol).

[DaSigntist]

I’ve still waiting for everything (motors, geckos, power supplies and breakout board) to get here (I hate waiting)

Since I have so much time to think and look at my machine I decided to buy some linear slides off eBay.
http://cgi.ebay.com/ws/eBayISAPI.dll...tem=2575324484
And do the Z axis right.
I figured the Z axis is the weakest link and I’ll deal with it now rather then later.

I bought a small arc welder to do the welding myself (never welded before) so we shall see how that goes.
Most of the welds are just tack welds that don’t need to look good.

MaxNC charged me a 10% “restocking fee” to return the motion setup they sent me which was wrong!
That’s $140 bucks + shipping + customs charges – I got screwed out of about $350. USD because of salesperson feeding me B.S. – not feeling too good about that.

It looks like everything will be here next week so I can get it finished in a week or two after that (fingers crossed).

[HomeCNC]

that's an expensive lesson. I'm glad you did not get fed up and stop wanting to build your CNC machine.

[balsaman]

I will never buy anything from them. (MaxNC)

Eric

[DaSigntist]

Howdy all,
Installed the Z axis with my new linear slides and installed my 1100 oz/in servos with wiring routed to my control box.
Installed two 12 VDC fans, breakout board, Geckos 320’s and I am awaiting my 2 48V 10 amp power supplies to be deliverd next week.
I still need to install my relays for the shop vac and router to remotely turn them on via software (MACH2).
Home and limit switches are installed and some reinforcing welding on the Y axis done as well.

Updates and pictures to come. . . .

[balsaman]

Cool...nice job. You da man!

Eric