My first CNC machine build - Help and advise gratefully received

[fentiger]

Hi,

My name is Steve. I'm a furniture maker and craftsman. I've been looking at getting a CNC machine for a while, mainly for carving letters into Oak.
I've had various different designs going round in my head for months but I've settled on something similar to these...
http://www.mycncuk.com/attachment.php?attachmentid=14423&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14424&stc=1
Something a little smaller than these about 4ft x 2ft

I've contacted CNC4YOU.CO.UK and have a quote of around £2000, which was my budget.
These are the parts I'm looking at...

2x RM1605-C7 ballscrew - 1200mm
1x RM1605-C7 ballscrew -600mm
3x BK12 Ballscrew support
3x BF12 Ballscrew support
1x SBR25uu rail kit -1400mm
1x SBR16uu rail kit -800mm
1x Nema 23 4Nm stepper motor kit x 4 Axis
1x Z Axis 250mm ballscrew with fitted Kress mount
1x Kress 1050
3x Nema 23 stepper motor mount
3x Ballscrew mount ID28mm
4x 8mm-10mm XD coupling 25mm-30mm

I've spoken with them today and they are also quoting me for a USB controller

I'm hoping to go ahead with the purchase of these parts in the next few days to be delivered next week.

I would like help on which bolts I would require and if anybody could point me in the direction of any assembly guides / instructions.

Thank you in advance for you help
Steve

[EddyCurrent]

I'm hoping to go ahead with the purchase of these parts in the next few days to be delivered next week.

Steve

Steve, the parts list does not include any electronics such as the stepper drivers etc. also it does not include the aluminium frame.
All I will say is this, I think you could build a better machine for the same price by getting advice from here.
I appreciate the build you propose might be easier than welding a steel frame for example but it depends on the quality you are looking for.
Have a look at some of the build logs here first. http://www.mycncuk.com/forums/253-DIY-CNC-Router-Build-Logs

[fentiger]

Hi,

Thanks for your reply.

I did ask if this list included everything I needed to built the machine. But I was unsure about the frame.
The design of these two machines seems quite simple and quicker for me to make.
I like how the stepper motors run directly on the square rail, but the rail they have selected for me is round.
So I'm not sure the design will remain the same with the parts they have selected for me.

The electronics are all in with stepper motor kit.

I'm about page 5 through the build logs, but haven't found anything quite right.
I think I'm going to struggle with the parts they have selected for me to make a machine similar to the two above.

Cheers
Steve

[Robin Hewitt]

Every time a noob designs their machine I pop up and say, "Do you really need 12" in the Z axis? It will give you a massive overhang because most of your work will be in the bottom 1 or 2 inches". They always swear blind they have stacks of 12" thick to do and carry on regardless.
Here you have 2 machines with monster Z travel and the bed fudged so they cannot use it. That single design facet tells you that you are looking at noob machines that have been fudged because they were designed badly.
Why not copy one of Jazz's recent machines, he is well past the stupid mistake phase. Why rip off problems when you can just as easily rip off something that works.

[Clive S]

Steve. Please don't go down the route of buying the electronics until you have decided and built the frame because as you learn (like we all have done) your goals will change.
That kit you pointed at will not be enough to build what is in the picture, as in the pic it appears its using rack and pinion drive system with the gear boxes on the motors etc.
.
CNC4YOU.CO.UK is a good company to buy the motors from but I feel you can do better buying the ball screws and rails, power supply etc. else ware.
In the kit you show 4 motors but three ball screws !! and it would be more usual to use 10mm pitch on the X & Y axis and 5mm pitch on the Z.
.
Keep asking questions no matter how silly and the good people here will guide you through the minefield.
Put a sketch up here before you buy anything. ..Clive
(Edit I missed the Z screw)

[fentiger]

Hi,

Thank you for you reply.

I shall keep on researching.

Have you seen these... https://www.inventables.com/technologies/desktop-3d-carving-cnc-mill-kit-shapeoko-2

Wondered if they are any good

Cheers
Steve

[irving2008]

In a word, no. Weak design, underpowered and overpriced.

[EddyCurrent]

@fentiger, have a look at this shapeoko thread; http://www.cambam.co.uk/forum/index.php?topic=4599.msg33867;topicseen#msg33867