[Islam]

No ball/lead screw
No rack and pinion
No chain and sprocket
No driving belt
No linear guide
stand alone table
5 axis
Zero backlash
Very smooth movement
The cheapest cost

It is my own upgraded technique using threaded steel pulleys and wire rope .. let us start talking by photos.
___________
The X-axis driving mechanism
Just one fixed stepper motor for the gantry

[Islam]

The Y-axis driving mechanism.
Motor is moving with Y-car not with Z-car.

[Islam]

Z-car using the same technique.

[Islam]

Stand alone table & 30.0 mm bar as a track.

[Islam]

After primer and hammer finish plating

[Islam]

Control unit chassis made by my diy cnc plasma m/c includes the following:

1- power supply, contactors, relays and rosets.
2- drivers & interface BOB and screened cables.
3- PC, screen
4- inverter
5- oem control switches.

[Islam]

Rotary axis (across X axis) under progress.
Able to rotate work pieces up to 350.0 mm ( 13.5") diameter.
Could be rotated around the Y axis to give the 5th manual axis facility.

[BassBone]

I really enjoy looking at threads such as yours which include ingenious approaches to DIY CNC. In this case, steel wire is strong in tension, so I can see why you chose it. I will be interested in seeing what challenges it introduces and how you deal with them. One thing that I see is in the first post the cable is winding around a rod, and I imagine that as the cable winds around the rod, the angle of the cable will change, so this will shift the alignment of the cable and possibly cause issues (just guessing). I am curious if this is a factor and how you deal with it.

Thank you for sharing your photos. I wish you continued success in your project.

I really like the color, by the way.

[Islam]

I really enjoy looking at threads such as yours which include ingenious approaches to DIY CNC. In this case, steel wire is strong in tension, so I can see why you chose it. I will be interested in seeing what challenges it introduces and how you deal with them. One thing that I see is in the first post the cable is winding around a rod, and I imagine that as the cable winds around the rod, the angle of the cable will change, so this will shift the alignment of the cable and possibly cause issues (just guessing). I am curious if this is a factor and how you deal with it.

Thank you for sharing your photos. I wish you continued success in your project.

I really like the color, by the way.

Thanks for your comment.
The cable is not winded around an ordinary rod but around a threaded rod and inserted inside its teeth , this threaded rod moves axially during its rotary movement via a fixed nut forward and reverse to compensate the axial displacement of the wire.

So the wire will be maintained straight without any angle owing to the axial movement of the threaded rod.

I think that the clip of the machine movement that I will post within a few days will clarify every thing.
But you can have a look to my DIY plasma in this thread, it is also by using wire rope but a different design.

http://www.cnczone.com/forums/plasma...cnc-forum.html

[BassBone]

That's a very clever way to accommodate the wire winding around the rod. Thanks again for explaining this and for providing the illustration.

[victorofga]

around 95 we built a painting machine with rope.. there were no issue the repositioning, because it painted in one pass..

I never tought it could drive real cutting machine..

very cool anyway.. folks could learn creativity from you..

[Islam]

This is a simple illustration showing the difference between the wire winded around an ordinary rod and that's winded around a threaded rod.
The pitch of the rod thread is about 1.2 times the wire diameter to allow an accepted clearance between the wire winding , this way achieves the following:

1-double friction between the wire surface and the rod which prevents slipping (two winds are more than enough to ensure a tight coupling)

2- prevents wire winding from overlapping or any chaos.

3- Control and organise the relationship between the radial and axial movement of the wire depending on the thread pitch.

[iwaskevin]

Thanks for your comment.
The cable is not winded around an ordinary rod but around a threaded rod and inserted inside its teeth , this threaded rod moves axially during its rotary movement via a fixed nut forward and reverse to compensate the axial displacement of the wire.

So the wire will be maintained straight without any angle owing to the axial movement of the threaded rod.

I think that the clip of the machine movement that I will post within a few days will clarify every thing.
But you can have a look to my DIY plasma in this thread, it is also by using wire rope but a different design.

http://www.cnczone.com/forums/plasma...cnc-forum.html

I like it great idea

[Coydog]

I have done this with Kevlar fishing Line. The issue you will have is that as it wind the wire position move. My test rig which used a 1/4inch 20tpi threaded rod the wire move about 1 inch side to side per every 13 inch of lateral move ment. this Side to side movement affect the geometry. unless you did like i did which is to put the drive at the gantry. and put the attachement of the cable to either end of the table and offset them accordingly.

My Machine used fishing lines, which can only handle 60lb per line with 250oz inch Motor the line will break befor the machine lost step. This is more then likely caused partially by the tension on the line. Also at about 10inch per sec Acceleration the line will break. My machine has a 50lb gantry and I used 4 lines when i did this test.

The machine with fishing was capable if runing a 1/4 router bit with 1/4 inch deep cut at 45 inch per min on ply wood. as long as the accel was low. And Rapid is in the range of 250 inch per min.

But after all this I thought it was a perfect cheap system for somthing like a 3D printer.

Attachment 264228

[Islam]

I have done this with Kevlar fishing Line. The issue you will have is that as it wind the wire position move. My test rig which used a 1/4inch 20tpi threaded rod the wire move about 1 inch side to side per every 13 inch of lateral move ment. this Side to side movement affect the geometry. unless you did like i did which is to put the drive at the gantry. and put the attachement of the cable to either end of the table and offset them accordingly.

My Machine used fishing lines, which can only handle 60lb per line with 250oz inch Motor the line will break befor the machine lost step. This is more then likely caused partially by the tension on the line. Also at about 10inch per sec Acceleration the line will break. My machine has a 50lb gantry and I used 4 lines when i did this test.

The machine with fishing was capable if runing a 1/4 router bit with 1/4 inch deep cut at 45 inch per min on ply wood. as long as the accel was low. And Rapid is in the range of 250 inch per min.

But after all this I thought it was a perfect cheap system for somthing like a 3D printer.

Attachment 264228

Finally, I have finished my machine and tested it, the machine is running very smooth and this issue is not existed owing to the axial movement of the threaded pulley as I have mentioned before which compensates this offset.

I will attach the clip of my machine movement.

[Islam]

My first cut using the rotary axis besides the 3 axes.

[Islam]

Some photos of the machine after finishing.

[Islam]

Auto tool zero & Y axis movement.

https://www.youtube.com/watch?v=osf9...ature=youtu.be

[Islam]

An adjustable derlin brake has been fixed along the axis of the rotary to eliminate any vibrations due to the backlash of the gearbox during the cut.

[Islam]

Part of the table has been designed to fix the small work pieces up to (15" x 30") using sliding bars and also used for square columns.