Newbie CNC Build

Hi Guys,

Long time lurker here, I have finally got to the point where I want to start my CNC Build. So before I start I would like to get some advise from the already experienced members of the Forum. I have many questions about the Build and also the Electronics.

First the Build:

The CNC will be made out of Steel as that is what I have access to a fairly low cost, I was looking at Aluminium Extrusion but the Price was Prohibitive. Also the other reasons I decided on Steel is for the rigidity as one of the materials I would like to work on is Aluminium. The downside of going with Steel that I see is that it is not as flexible as the Aluminium Extrusion is, if you want to modify something in your build, are there any other Pros/Cons ?

I did find this CNC on Youtube. It is made of Steel and seems to have a good design, I would like to copy this design, is there anything in the design I should look out for?

I have a fairly small space to put my CNC, so the first thing I have nailed down is the size of the overall Base, 1200mm x 1000mm. With this size I feel I can comfortably work on 1/8 Sheets of Wood/Acrylic or Aluminium Blocks.

I have started the design process, here is the Base. I will post more pics later on as I get time to draw the parts.

Attachment 5431

Now to the Electronics:

My Goal with this would be to have a Accuracy and Speed but I am fairly sure I cannot have both, so I would like to be more on the Accuracy side than on the Speed side.

I have been looking at various electronics and Motors and I am not really sure what to get to achieve my Goals.

So far I have gathered that:
- There is no good or bad PSU, just get one that is suited to run your Steppers/Drivers etc...
- Digital Drivers and better than Analogue Drivers
- Servos are better than Steppers

Then again with all this above I could be Horribly wrong, so if I am, Please do not sugar coat it!

Thanks in advance for the Guidance, I am sure there will be more questions!

The machine on youtube is very basic in its design with bearing running on what looks like steel box section. This wont give you high accuracy. the box section wont be perfect for starters and also with bearings and running surfaces you tend to get crap between them and this gives problems. What you end up with is stuff ground into the running surface and this makes the bearing jump or stick when it tries to pass over it, I have seen this happen many times on the profiling machine I work on, you need to keep them very clean. Also if you want to cut ali I think the design would be too weak for it unless you took very light cuts. I think it would need some serious beefing up. Have a look through the forum builds and Im sure you will find something there to suit your needs that you can copy and modify to suit. Both accuracy and speed are obtainable relatively cheaply and stepper motors will suit your needs nicely when added to some linear bearing and slides and some ballscrews. Servos are better but cost loads more and the controller for them would also be more expensive. I use USBCNC myself and I like it but there are others out there for you to try. As for PSUs there are good one and bad ones. Buy a decent quality one is my advice.
Apart from that welcome to the forum.

Ian

Hi Ian,

Thanks for the Reply.

I like the design that JAZZCNC is working on, a picture here: http://www.mycncuk.com/forums/showth...d-General-Help

Would this be a more solid design with the high sides? Any tips for designing a Strong machine for working on Aluminium?

The USBCNC looks interesting, have you had any issues with it? I was looking at GeckoDrives, what you think of them?

Going back to the Drawing board for now.

Hello Junkie

welcome to the forum
First what is your budget for the build.

James

I am looking at around €1000 for the Build Excluding the Spindle.

The machine JAZZ is working on would be fine for ali I would think. If you think the side are a little too high for you then you could follow the same idea and lower the frame height a bit to suit. I like USBCNC and so far havent had any real problems with it once I got a bit further up the learning curve. Its getting better with each new update. Dont know about the Gecko drives as I havent used them.

Ian

Thanks for your input, I am hoping that there will be more from other users.

I have looked through the Forum and have seen a machine similar to JAZZCNC with lower sides, made by Jonathan. I have PM'd him to see if he can post more pics of it as it looks like it would do the Job.

What other designs do you think are suitable for the Job?

Quote:

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Originally Posted by JunkieHobbo

I am looking at around €1000 for the Build Excluding the Spindle.

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Have a look around the forum. You may find that your budget is a bit low for cutting al. But you wil get value for money if you listen to our experts.

Bruce

Me and jazz are working together (Well he's the master so I am watching and listening and learning) to develop this machine, as my goal is to cut aluminium, we are bashing out a few details first and he's going to draw up a final design. And of course I will let you all know and keep you all updated!

@ motoxy: I have been and I am currently gather more information and then back to the drawing board. I know the Budget is tight, I do have an emergency fund if upgrades are required... ;)

@ kylelnsn: Would like to see the drawings once complete. Have you decided on the Electronics yet?