Messages

8731

General Mach Discussion / Re: Strange Problem

« on: March 10, 2009, 01:34:46 PM »

I would suggest that you check the LPT connection between your computer and machine. A broken / intermittent connection on the Y axis step pin (whichever one you have chosen) could possibly cause this problem.

Tweakie.

8732

Tangent Corner / Re: Metal shredder

« on: March 10, 2009, 11:51:43 AM »

Wow ! - don't want to let your CNC anywhere near that.

Tweakie.

8733

Show"N"Tell ( Your Machines) / Re: CNC watch lathe

« on: March 10, 2009, 10:10:56 AM »

Nice work Vince.

Tweakie.

8734

Show"N"Tell ( What you have made with your CNC machine.) / Re: Building a 4th Axis from scratch.

« on: March 10, 2009, 10:00:29 AM »

I haven't the faintest idea how to set up Mach to drive a fourth axis yet. There are plenty of posts on this subject (i've checked already) so I will have to do a lot of reading before I can make anything.

Tweakie.

8735

Show"N"Tell ( What you have made with your CNC machine.) / Re: Building a 4th Axis from scratch.

« on: March 10, 2009, 09:23:33 AM »

Just finished making the stepper motor mounting this morning - can't wait to try it out but I have to do a bit more electronics to extend my driver card to include a fourth axis driver.
Fortunately, I have a stepper test rig so I can run it on the bench just to make sure there are no tight spots and that the stepper has enough torque.

Here are a couple more pictures.

Tweakie.

8736

General Mach Discussion / Re: Newbie needs help

« on: March 10, 2009, 09:12:15 AM »

Gerald,

Please don't forget to post some pictures of the stuff you make.

Tweakie.

8737

Tangent Corner / Re: Metal shredder

« on: March 10, 2009, 04:02:29 AM »

In the UK they call these machines fragmentation plants. They usually have 4 hammers (which are bell shaped in section) which are free to pivot within a central hub which is rotated by a motor (big motor). Underneath the hammer assembly is a grille of about 100mm mesh and everything that is placed in the hopper above gets smashed by the hammers until it drops through the grille.

The machines are usually conveyor belt fed from grab cranes and everything that goes in (cars that have been previously crushed into blocks - scrap etc.) comes out as scrolls of gray metal witch all looks exactly the same. Quite an amazing sight.

Tweakie.

8738

Show"N"Tell ( What you have made with your CNC machine.) / Re: Building a 4th Axis from scratch.

« on: March 10, 2009, 03:45:17 AM »

Hi Folks,

My approach to cutting the gear wheel was nowhere near as technical as it should have been. I already had a 60 tooth spur gear so I knew in advance the diameter the finished gear was to be cut to. I machined 60 slots around the circumference of the blank (for the tap to engage) and went for it like it was a knurling operation on a lathe. The initial problem is that the number of teeth versus the circumference did not match because I did not machine the blank to the finished shape )=(   it was initially too large in diameter at the point where the tap first touches (difficult to explain but I hope you understand). So there was some argument between the tap and the blank but this subsided to harmony when the diameter and pitch became correct.

As with all things, if I was doing it again I would probably do it a different way but the way it was done worked. I have since seen examples of this type of gear which has been cut radially into two discs which are spring loaded against each other as a way of eliminating backlash.

Tweakie.

8739

General Mach Discussion / Re: Newbie needs help

« on: March 10, 2009, 03:26:11 AM »

Hi Gerald,

We seem to have hijacked your thread over the license issue - sorry.

Have you now resolved the zero tool position on the work ?.

Tweakie.

8740

Show"N"Tell ( What you have made with your CNC machine.) / Re: Building a 4th Axis from scratch.

« on: March 09, 2009, 08:42:33 AM »

Thanks Guys.

I will post more pictures as the project progresses.

Tweakie.