Scratch Build – In Progress My Now finished mean Computer Numerical Control machine build

Right today I did the Carriage plates



3 of these.



All done now



Oh forgot to say the nut numbered 2 in the diagram is a eccentric nut for adjustment I'll post a picture of it tomorrow.

 

The eccentric nut, every carriage plate has two of the rollers adjustable with these.

 

Doesn't look anything like me!

 

The red ones do

 

From seeing those plates complete, I think I maybe underestimated how big this would end up.

What's your first project once you have it setup and running ok?

 

How does eccentric nut work? I can see it's off centre hole, and I've read it's to adjust the tension of the v wheel, but how does it being off centre achieve that?

 

If it's the usual sort, it has a boss which projects from it into the hole, like this:



That way, rotating the nut changes the position of the spindle of the pulley.

 

I think the idea is as you rotate it, it will shift axis of the roller around a bit. With the axis centre following a circular path with a radius that matches the distance between the nuts centre and the offset centre.

No CNC experience myself mind. This is me just eyeballing things with a 'What else could it be?' state of mind.



Edit: Ninja'd

 

oh I see, that hole is bigger on the plate, and the boss goes into the hole and moves the v runner up and down. Solved thanks.

 

Yes siree - isn't engineering ace?

 

It's not that big around 24inches square I reckon of course the actual work area will be smaller, Although later I'll be making it big enough to have a work area I can fit a case side panel in that will allow me to be able to do some nice side panel designs.

There's a few test programs I'll be trying, one that is just writing on a A4 sheet and another cutting a design from some MDF after that I was thinking of maybe doing a simple fan grill.


Still have to learn how to do the programing / code for it to cut it

 

From their website:

Footprint 550mm x 500mm
Cutting Area 300mm x 300mm x 50mm

However the key thing is:

Expandable - Yes

 

I spoke to the company yesterday about buying longer rails and there's such a big demand for these kits they won't have any stock in till late August

 

When that cnc is done, you can make your own rails/pieces!

I'm sure they make their own with that cnc.


And for the code, don't worry it's not complicated, need to learn 4-5 commands to understand the code so you can check it before milling.

 

lol if only actually I would need the machine to be bigger than the rails I would be making

I'm thinking of buying a program I've seen that will allow me to design something and convert it to the needed code for the machine £95 but worth it if you get the use of it.

 

This looks awesome, I want one! Can't wait to see what you produce with this when it's up and running.

 

Todays update,

First there's a couple of boring bits before going any further all the rails needed to have the end holes tapped with a thread two on each end and the electrics needs to be tested, the last thing you need is to have to take it all apart again because the electrics are no good.

Using the supplied tap all the rails was threaded two to each end



Now to get the parts for testing 4 motors



and the ARDUINO



the two boards fit together



Next wire it all up, power connected and connected to the PC via a USB cable



Now I need a bit of software to control the motors





Right took some messing around to get the PC to recognise the ARDUINO I had to hunt down the driver and install it but once that was done all the motors worked fine

 

Next update.

Now that I know the motors and electrics are all working it's time to build the Z axis assembly, there's quite a lot of bits to this one so picture heavy

This plate will be where the spindle attaches to, the picture shows the back which will run up/down the z axis rail also there is a threaded block that the threaded rod goes through no pic of it I'm afraid.



Next shows the brackets the spindle is held on by



Ok next the parts for the Z axis rail and motor mounting bracket notice the flexible coupler to join the motor and the threaded rod in between the two mounting plates there is a roller bearing and 10 spacers



Motor, spindle plate and Z axis rail assembled

 

Two updates today

So time to put the toothed cogs on the motors and fit the motors in the carriage plates



Pretty tight fit these but went on with some persuasion



For the Z axis it requires two carriage plates one with a drive motor and one without



Here comes the boss to check the work



Looks like she's happy with the work so far





More tomorrow