Thread: CNC Gantry Router #A

Thanks Chris,
Yeah spot on it depends on the pitch of the screw and the resistance of the motor when power is off.
Obviously I don't know what it is going to do on this machine yet so just thinking ahead.

Some more progress.

This is the Y aixs and connection plate between Y and Z. I have the rails on top of Y and at the back as I figured that was the best position for them to be protected from sawdust and swarf. I have built a 16mm thick aluminum box around the beam as a connection to the Z axis. I have milled 5mm deep housing joints for those - you just can't take the woodworkers away.
Still have the ballscrew to fit and this will be at the back of the beam as well.

Z axis was also mounted and I am happy with the potection and motor mounting. When I change this spindle for the larger one I will definately have to fit a brake or use a rock to hold it up when it is not powered.

Rod,
It is looking brilliant as usual! I am really pleased with your progress as I have just mounted my gantry and am about to embark on Y & Z axissss's (sp).

I hope to have some photos today, but I have a problem ... my table top is horizontal and in my workshop every horizontal surface attracts 'things' and 'things' spoil photos, not like your well ordered and arranged photos!!

Is that your air cooled spindle that you have mounted? Do you know if any of our forum have actually got an air cooled spindle in operation and what the results are?

Cheers for now,

Alan

Firstly I have to apologise, I've just seen this thread, but haven't taken the time to go through it from the start. I have to say that the build looks fantastic, very professional. I'm in the process of a build with the T-Slot, I have two pieces of 45x90 Heavy for my Y gantry beams. What size is your gantry beam and how do you find the T-Slot? What size are you steppers? What speeds are you getting? Is that the spindle from HomeShopCNC....I was looking at it, but got a reasonable quote for a new Colombo spindle from Germany, and cant decide whether to spend the extra few hundred on the Colombo?

Thanks. Looks fantastic.

Hi Alan,
I laughed at your horizontal surface as I am just as guilty as you. Note the gantry is pushed to the front of the machine and the photo is cropped to hide the mess.

Yes it is the air cooled spindle and I don't know if others have one hooked up yet. I lent a fellow my water cooled spindle same size as this one and he has reported back that it is performing very well. So that I could compare the two I decided to put the air cooled on this machine. I am being a bit lazy also because I do not have to run coolant tubes and pump by using this one. Later I will fit a much larger 2HP water cooled spindle.

Thanks thkoutsidthebox,
The machine has not been commissioned yet so speeds are unkown. I will use 497oz on X and Y with two to one pulleys on 5mm pitch screws. I am hoping to use the lower down stepper torque better by using the pulleys. Z has a 269oz motor on it in the photo and I may swap this for a 497 as well.

The spindle I got direct from China and it looks to be the same quality as HomeshopCNC but cheaper. About $500US will get you one delivered - example here

My Y axis beam is 120 X 80 heavy and is doing the job well for a 1200mm span.

Nice work as always Rod.

Just wondering whats the cutting area?

Thanks Chris,
At this stage 1200 by 900 by 130 but I haven't fitted the ballscrews. I need a full day to machine the mounts and I have other things to do.

Did the Y axis ballscrew and mounts on the weekend. Worked out to be about four hours of machining on the X3 as there are 14mm deep pockets in the aluminum.

Using a 2 to 1 pulley ratio to step up the speed on this machine. I am using 5mm pitch screws as there are more threads on the ballnut verses a 10mm pitch and the pulley ratio brings it up to the equivalent of the 10mm pitch. With pulleys and a belt you are less prone to mid band resonance so another benefit.

That is my theory and I'll see how it goes when I run it.

I have made sure all the little jobs have been done during construction so I am nearing the end of it now. Mechanically I only have to do the two screws for X axis and mount the limit switches. I then need to run all the wires to the motors and spindle and will be using energy chain to support the wires.

I will then move on to a little mill conversion I have been gathering parts for.

I should have made a bigger machine because to take the photo I had to stack stuff two deep to clear the table. )

Looking the goods Rod, I envy the time you have to get in and machine the supports and move on with a few projects at once. lol. I like the idea of the ratio pulleys on the ballscrew, like you said, it should also cut back resonance, which should allow the machine to run even faster without stalling. Not long now, keep up the good work and can't wait to see yet another clean build up and running.

Daniel

Looking good now, should not be much longer now

Thanks

Bob,
Good to hear from you. How is the retro fit going on your machine?

Looks good Rod ! ... now to just find a suitable rock

Russell.

Thanks Russell,
Rocks are an essential CNC component.

Heh yeah, sometimes I think we may have them in our heads for getting into this stuff in the first place

Russell.