[cncjunky2011]

Hey guys,

Not really new to machine building but thought i'd share this one as much as I can with everyone. Building this for a purpose built application to machine large sheets around 3000mm long x 1250mm wide. The cutting area will be around 3500 x 1400.

The machine has a Z axis clearance of around 200mm as this is all thats needed, the Z is designed to lift the spindle right up to make tool changes easier as the collet will be pretty high and easy to access. Ballscrew and nut are hiwin.

All carriages & rails are 20mm hiwin, carriages for the X are flanged versions and all others are double lip sealed.

Gearbox setup is 5.1:1 and allows a resolution of around .0003" The motors all operate at around 3000rpm which will give rapid speeds of around 50,000 mm/min.

A note regarding the motors so far, DMM have been nothing short of amazing. The support to date has been outstanding and im looking forward to integrating the motors into the final part of the build.

Anyway enough of the waffle, lets get some images up here!

[cncjunky2011]

Here's the machine design:

[cncjunky2011]

Here's some images of the initial frame layout and fabrication

[mactec54]

cncjunky2011

Looks like you are on your way for a nice machine/build,also a great choice going with the Dmm system

[cncjunky2011]

Here's the bits from DMM:

X Axis

92GM-DHT-72
•Rated 750W
•Peak stall Torque: 7.2Nm
•Continuous stall Torque: 2.9Nm
• Rotor Inertia: 2.05 Kg-cm2

Y & Z Axis

60EM-DHT-36
• Rated 400W
• Peak stall Torque: 3.60Nm
• Continuous stall Torque: 1.28Nm
• Rotor Inertia: 0.7 Kg-cm2

[cncjunky2011]

Here's the parts for the gearbox and fabrication photos. All the aluminium in this build log is being machined on one of the other machines I have previously built.

[cncjunky2011]

Here's some images of the X setup and dry test fitting of the gantry plates. These are just to test, aluminium ones have been included in other images.

[cncjunky2011]

Here's the final machined gantry plates from 20mm aluminium plate:

[cncjunky2011]

For anyone who's unsure about keeping the rails parallel to each other here's one way of doing it. I have done this in the past so have become pretty good at it. No matter what steel you use, hot or cold rolled the walls are never truly 90 degrees. The best way is to use epoxy resin to level the rails, I managed to get them within .1mm which is within tollerance for the hiwin carriages. The x-setup glides smoothly using this method and no need for ground rails like some may suggest, not for my build anyway as this is as accurate as I will ever need myself.

[cncjunky2011]

Some initial images of the Y axis and end plates:

[cncjunky2011]

Some images of the Z axis fabrication so far:

[cncjunky2011]

This is from another machine but thinking of integrating this into the build. Its a vacuum board machined from HMW plastic. I used one of the extractor vacs on it and for larger pieces above 300x300 you cant move them. Anything bigger and it sucks the hell out of them.

[cncjunky2011]

More images to follow in the near future. I dont have much time available but will try to add some more images next week.

I have some videos of the vacuum which Ill upload too as I know this is a key issues for many DIY builds. Im planning to get a 7.5kw vacuum at some stage in the near future which I trust will be the end of the vacuum bed design. For now the extractor setup is outstanding it must be said.

[cncjunky2011]

Here's a few more images before final assembly and installation of cables and igus chain/spindle.

[cncjunky2011]

Used a 3.5mm jack and spiral cable for the touch plate. This will be stored on the gantry so wherever the machine is the touch plate will be too.

[cncjunky2011]

Just testing the servos, mechanical stuff is finished and starting to tune and test the DMM servos. I will post some information on this and videos of the machine operating soon.

Currently cannot get past 37000mm/min due to kernel restrictions in mach3, initially the 100mhz seems flakey too so I can see me dropping the kernel speed to 75,000 until I decide how best to achieve the 56,000mm/min the servos should be capable of achieving.

[louieatienza]

Just testing the servos, mechanical stuff is finished and starting to tune and test the DMM servos. I will post some information on this and videos of the machine operating soon.

Currently cannot get past 37000mm/min due to kernel restrictions in mach3, initially the 100mhz seems flakey too so I can see me dropping the kernel speed to 75,000 until I decide how best to achieve the 56,000mm/min the servos should be capable of achieving.

pretty awesome work so far, love the paint scheme!

[cncjunky2011]

Thanks, just trying to sort out the motor tuning and speed settings in mach3. Didn't really consider the limitations of mach3 and the parallel port, maybe have to consider using a smooth stepper or some other solution to get things flying along at the speed the machine has been designed to operate at (56,000mm/min).

Also in the middle of resolving a problem with the larger x motor/servo encoder as the servo encoder extension cable is causing some problems with the encoder not operating correctly. DMM are aware of this and provide a noise filter for the DYN-3 drive which uses 240VAC.

Ill post further information as it unfolds!!

[charlieslasher]

sweet build lots of stuff i like. What is the rubber gasket in the vacuum table? and whats in the touchplate? dose it need a springloaded surface?

[ger21]

Currently cannot get past 37000mm/min due to kernel restrictions in mach3, initially the 100mhz seems flakey too so I can see me dropping the kernel speed to 75,000 until I decide how best to achieve the 56,000mm/min the servos should be capable of achieving.

A quick solution is to use the electronic gearing in the drives.

Is the black finish anodized, powder coat, or paint? It looks really good.