The £200 CNC

[Wabbit]

Hi Wotsit,

I'm kind of following you path to a CNC machine as I bought the plans from Patrick at buildyourcnc.com

I have to date - 1 week after plans arrived - failed to make a start.

Still trying to soure basic MDF in the correct sizes to match imperial plans from Patrick in the UK.

3/4 MDF on plans 4' x 2' = B&Q not correct size to start off with ...

We seem to be 18mm MDF only thickness and 3/4" is like 19.nnn

Have I made a big mistake already ??

Guys ??

[irving2008]

Hi Wotsit,

I'm kind of following you path to a CNC machine as I bought the plans from Patrick at buildyourcnc.com

I have to date - 1 week after plans arrived - failed to make a start.

Still trying to soure basic MDF in the correct sizes to match imperial plans from Patrick in the UK.

3/4 MDF on plans 4' x 2' = B&Q not correct size to start off with ...

We seem to be 18mm MDF only thickness and 3/4" is like 19.nnn

Have I made a big mistake already ??

Guys ??

You have to adapt the plans for the different thicknesses. MDF in Europe is 6, 9, 12, 18 or 25mm, while in the US its 1/4", 3/8", 1/2", 3/4" and 1". Its not a big issue; in most cases it makes no difference, in others you have to do a bit of thinking and make an allowance for the difference by adding a mm where appropriate (so for example if you were making a box, you'd need to make two of the sides 2mm longer to get the same external dimensions if that was the critical measurement). The tolerance on MDF isn't that good anyway, its within 0.5mm so the difference between 18mm and 3/4" could be as little as 0.5mm anyway.

[CraftyGeek]

Hi Wotsit,

I'm kind of following you path to a CNC machine as I bought the plans from Patrick at buildyourcnc.com

I have to date - 1 week after plans arrived - failed to make a start.

Still trying to soure basic MDF in the correct sizes to match imperial plans from Patrick in the UK.

3/4 MDF on plans 4' x 2' = B&Q not correct size to start off with ...

We seem to be 18mm MDF only thickness and 3/4" is like 19.nnn

Have I made a big mistake already ??

Guys ??

I'm just finishing the build of the same machine - I've used 18mm.

Start up your own thread & I'll offer you a few of my own findings.

[Wotsit]

Sorry for the long time with no updates but life took over! However I have now ordered some more parts, horray!

SY60STH86-3008BF Nema 23, 1.8 degree hybrid stepper motor with a holding torque of 3Nm (425 Oz-in) £88 from ebay

and

3 Axis TB6560 Stepper Motor Driver £47

As soon as they arrive show my progress

[irving2008]

Sorry for the long time with no updates but life took over! However I have now ordered some more parts, horray!

SY60STH86-3008BF Nema 23, 1.8 degree hybrid stepper motor with a holding torque of 3Nm (425 Oz-in) £88 from ebay

and

3 Axis TB6560 Stepper Motor Driver £47

As soon as they arrive show my progress

What voltage are you going to run that driver on? And what leadscrews have you got?

[Wotsit]

Only 18V with a trapezoidal lead screws, i was going for 8mm bar and derelin nuts but think it might be worth an upgrade. Cost is the major factor for this project, just over the £200 mark now and hopeing to stay there for this one.

[irving2008]

Only 18V with a trapezoidal lead screws, i was going for 8mm bar and derelin nuts but think it might be worth an upgrade. Cost is the major factor for this project, just over the £200 mark now and hopeing to stay there for this one.

18v with that motor/driver combo and 1mm pitch screws will give you a top traverse speed of around 150mm/min assuming direct drive... but then speed and cost are mutually exclusive!

[Wotsit]

Speed is not that important for this project, just trying to use what i have available at the moment. I do also have a 100VA transformer that supplies 34v open circuit but i think that might be to low current and too high voltage for my driver.

Really hope i can cut alu even with a tiny feed in the end.