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matthewb
16-03-2015, 11:01 PM
belt on belt/servobelt.

Does anyone have any direct experience of using this system?

I am looking to build a machine based on this principle.

I will have an 8000mm Y axis and a 1600mm X axis gantry.

The machine will be for fabric cutting so light duty and either a tangential pizza wheel cutter or gantry mounted co2 laser, but either way not heavy loads.
It will need good rapids- 0.5-1.0 meters per second.

I am erring towards a tractor belt small loop acting on a glued down base belt rather than 2 full length belts. Seems silly to use twice as much belt as i need.


thanks for your help!

GEOFFREY
17-03-2015, 12:26 AM
Does that mean it acts like rack and pinion? G.

matthewb
17-03-2015, 12:31 AM
Yes
http://bell-everman.com/products/linear-positioning/servobelt-linear-sbl

that is a link to the commercial version. belt stretch is limited to the amount of belt it takes to mesh with the bottom "rack" and go over the pinion so it should greatly improve a belt system. zero backlash apparently?

Kind of hoping someone else has done this system and can warn me of the pitfalls ... but if not.. ill do it and report back.

Ger21
17-03-2015, 01:52 AM
I built a prototype, but never tried it out. I decided to re-design it to be stronger and handle more power.

johnsattuk
17-03-2015, 10:34 AM
I built a prototype, but never tried it out. I decided to re-design it to be stronger and handle more power.

I am looking at using a servo-belt at the moment, could you give any pointers as to how you designed this.

John

johnsattuk
17-03-2015, 10:43 AM
I am erring towards a tractor belt small loop acting on a glued down base belt rather than 2 full length belts. Seems silly to use twice as much belt as i need.

If it is a horizontal drive, the full length belt is very good at keeping the base belt clean

John

Ger21
17-03-2015, 12:09 PM
I am looking at using a servo-belt at the moment, could you give any pointers as to how you designed this.

John

Here are some pics

http://www.cnczone.com/forums/linear-and-rotary-motion/59570-forum-post933535.html#post933535

http://www.cnczone.com/forums/linear-and-rotary-motion/59570-forum-post934595.html#post934595

http://www.cnczone.com/forums/linear-and-rotary-motion/59570-forum-post969827.html#post969827

Boyan Silyavski
17-03-2015, 07:20 PM
What belt you would use? T5 or HTD5?

Have you considered to cast the belt on the frame side from epoxy resin?

johnsattuk
17-03-2015, 07:32 PM
Would be nice if you could buy steel rack with T5 teeth, perhaps stack some laser cut ones :cool:

Ger21
17-03-2015, 08:06 PM
HTD5 won't work, it needs to be T5 to mesh with itself.

johnsattuk
17-03-2015, 08:11 PM
Hypothetically, If you were making a metal rack could you cut it to suit other belt sections

matthewb
17-03-2015, 09:47 PM
apparently the Gates powerdrive profile works too
found this thread (http://www.cnczone.com/forums/linear-and-rotary-motion/59570-forum-2.html?) on cnczone.

I am going to glue the base belt down with double sided sticky tape (sailmakers version)

matthewb
17-03-2015, 09:49 PM
If it is a horizontal drive, the full length belt is very good at keeping the base belt clean

John
yes good point, im probably going to have the belt teeth vertical ..... probably... but that is yet to be decided 100% so.....




Here are some pics

http://www.cnczone.com/forums/linear-and-rotary-motion/59570-forum-post933535.html#post933535

http://www.cnczone.com/forums/linear-and-rotary-motion/59570-forum-post934595.html#post934595

http://www.cnczone.com/forums/linear-and-rotary-motion/59570-forum-post969827.html#post969827

Thanks Ger21, i will look through at your system

Boyan Silyavski
17-03-2015, 10:29 PM
HTD5 won't work, it needs to be T5 to mesh with itself.agree on that but it zeems doable
https://www.youtube.com/watch?v=T9QU3YQe-Sc

tropostudio
14-05-2015, 08:50 PM
I'm pretty impressed with Mike Everman's Servo Belt concept. I first ran across it in the threads on CNC zone Gerry refers to. There more on it on Everman's own blog at http://mikeeverman.com/. It seems like a great solution to the problems of belt stretch in conventional systems and the limited tooth engagement and resulting low shear strength and backlash compensation I see in CNC fabric cutters like this: http://carlsondesign.com/plotter-cutters/pro-plotter-cutter.

What about making the belt on the drive motor side a continuous loop (tank tread) and skipping the full length top belt? If you mount the belt system upside down, similar to how you see racks mounted on many CNC router axes, the protection from dust or chips seems unmerited.

Regards,

Chris Krumm

johnsattuk
15-08-2015, 04:32 PM
What about making the belt on the drive motor side a continuous loop (tank tread) and skipping the full length top belt? If you mount the belt system upside down, similar to how you see racks mounted on many CNC router axes, the protection from dust or chips seems unmerited.

Regards,

Chris Krumm

Have been planning a moving table router and wanted to try a Servobelt design. I had some Vexta 5 phase motors with 10-1 low backlash gearboxes which I wanted to use. Wanted a sort of modular self contained drive that I could bolt onto the frame, I shall be using a dual drive and will sync the drives with a shaft between the motors.

The std. 37mm OD bearings are assembled on steel tubes for alignment, they act as spacers for the side frames and are clamped together by the mounting bolts

The engagement with the belt on the table, is set by the outer bolts in the chassis having slotted holes in the frame. The belt tension is set by moving the motor in the slotted holes in the chassis plates, also carries an outrigger bearing for the 18 tooth pinion.

I have carved a setup out of wood before I waste any aluminum :concern: