Monday, 27 February 2017

1000ipm - Episode 138


Do I really need my machine to run at 1000ipm?
No I don't and there are several reasons behind this. First the savings in machining time are so small that it might as well ne nil for 2D and 2.5D machining. For 3D machining the savings are nil. It is not practical to cut at 1000ipm on a homemade machine. The better option is to make 1 deep cut at a slower speed rather than 5 or 6 shallow cuts at high speed. This is why many commercial machines cut in 1 or 2 passes. When it comes to 3d machining the maximum speed of the machine is irrelevant with accereration the determining factor in overall machining speed. A larger machine which cannot get up to speed quickly will be slower than a smaller light weight machine with high accereration.
Now don't get me wrong. It is nice to have a machine that can quickly get from one end of the table to the other but there are limits to how fast you really need to go.

It isn't how fast your machine is it is how quick it's fast.

just my thoughts on the matter.


Sunday, 26 February 2017

DIY Cable Management - Episode 137

DIY Cable Management

The last thing I need to do after the upgrade is replace the cable management on the Y axis. This is bacause after the upgrade the Y axis could not get full range of motion because the existing cable management was too short.

For demonstration purposes I show how the X axis cable management is constructed though the Y axis is made the same. The only difference is in the way the way it is connected at the ends. Each machine is different and you will need to find what method of attaching the cable management works best for you.


This is not the only type of cable management available for CNC machines but is is one of the simplest and cheapest. Other systems use drag chains. These are relatively cheap to purchase compared to what they cost some 4 or 5 years ago. At $10 USD per metre these are now easily affordable and once my machine is finally complete I will look at getting some of these for my machine. Until then i will continue with the system that has done me proud for the last 8 years.

Drag Chain supplier

Disclosure:  By purchasing through the link provided you are supporting my channel at no additional cost to you but please do not feel obligated to purchase any item shown here. Simply entering through any link on this page and making any purchase on Ebay will support my channel. Your responsibility is to yourself not to me. 

I have purchased from this supplier in the past without any issue though I have not purchased the item in the link. Search for other suppliers and chains as they come in various shapes and sizes. While this one will be fine for me it may not suit your machine so shop around.

Drag Chain

<a target="_blank" href="">Drag Chain</a><img style="text-decoration:none;border:0;padding:0;margin:0;" src="[CACHEBUSTER]">

Friday, 17 February 2017

Machine Upgrade - Episode 136

Machine Upgrade

The time has come and I can put it off no longer.
Having built my new Y carriages I decided my desire to know if they worked out weighed the concern I had that they wouldn't work. As the job went along I started canabalizing parts off the old carriages to create new parts to mount the SuperPID and cable management system. If I was forced to return to the old carriages I was going to have a real problem. I am fortunate that I don't need to retreat but it bacame clear as the upgrade proceeded that all was going to be fine. The Carriage install took about 4 hours of labour with a vast majority of that being used in working out how to reinstall the SuperPID, Cable management and motor connectors. The old carriages were made of MDF so screwing peices onto the Y carriages was no problem. Not so when they are mad of Aluminum and steel.
The upgrade was done over 2 days with the carriage install done on day 1 and the disassembly and cleaning of the X carriage done on day 2. The X carriage maintenance was long overdue and of course it required some TLC after being neglected for quite some time. Now it is reassembled and adjusted it is working better than ever.

With the upgrader of the Y carriages comes a greater machining area on the table.
The V-Bearings are spaced further apart than on the previous carriage by about 4 inches which is why I needed to lenghten the top Y rails but having added another 8 inches to the rail I now have an extra 4 inches of travel. I have also gained a few inches of travel in the X direction as well because the new Y carriages are narrower. Whether I retain this in future upgrade to the x axis will remain to be seen.
Another Bonus is I was able to increase the Z travel so will be able to make larger projects.

Upcoming Upgrades
I have recently purchased an air cooled spindle and will be installing it in a future episode. I has not yet arrived but I am waiting as quickly as I can. 
Stay tuned for more CNC madness.

Sunday, 12 February 2017

Grinding V-Rails Part 2 and a mystery object - Episode 135

Grinding V-Rails Part 2 and a mystery object

Continuing on with the rail upgrade for my machine I show how I complete the rails by putting the mounting holes in them and then after painting the rails I need to remove any paint that had accumulated on the V part of the rail. Leaving this on the rail will cause it to come off as the V-Bearing rolls over it and it will accumulate on the V-Bearing. This is a problem to remove from the bearing and can be avoied by simply cleaning the rail before installing it.

Another part that needs to be made it a mount to attach the X rail to the new Y carriage. This is done with the aid of some box section steel and by using a simple jig, drilling holes in both the V-Rail and the X rail mounting block can be done very easily and accurately with minimal measuring.

The upgrade process

In a future episode I will install the new Y carriages and attach the existing X rail. I anticipate a few issues while doing this install with the most obvious being how and where to mount the SuperPID speed control currently mounted to one of the Y carriages. I may also need to add additional bracing to the X rail to attach it to  the Y carriage. These are issues that will be addressed as the install proceeds. 
At this time I have no scheduled time for the upgrade. It will depend on available tiime but it should be soon.