Building the tools to build the boards.

[fluidity]

Started a project a couple of months ago to build my own CNC machine to try building board moulds with CNC instead of my earlier methods.
Getting most of my gear through aliexpress and steppersonline. At the moment it's looking like I have 120mm height on Z axis, 665mm width on Y axis and 1620mm on my X axix. This will give basically a biggest board size with a small mould sealing perimeter area.

Steppers, controller/drivers, PSUs and 1500watt water cooled spindle motor are from steppersonline.
From aliexpress I got "2pcs SBR12 - 1800mm linear rail bearings guides + 4pcs SBR12UU block cnc route" The Linear rails came very slightly bent which I expected... china to NZ by air! Still very usable though. I've mounted them on wooden rails on an 18mm thick plywood base.
These bearings have a tension adjustment in the middle.
I also got "HLTNC 2 set linear rails HGR15+1 ballscrews SFU1605 any length+ballscrew supportBK/BF12+1 couplers for CNC" for my Y axis. I've mounted these bits on a glued plywood and MDF gantry. For the Z stage I bought this: "3D printer DIY NEMA 23 c-beam Z axis kit CNC Z-AXIS ASSEMBLY kit TR8*8(2mm) lead screw Linear Actuator Bundle kit set". It was a bit loose so I've tightened it up, it's carrying over 4kg of spindle motor!

Currently I have the axis all assembled, waiting for some correct sized flex couplers and then I'm going to fix in the Y axis motor and put dual steppers on the X axis (by each X rail). The stepper motors are all bipolar Nema 23 and I've set up an arduino control board to test the Z axis which is working really well. Waiting for each remaining item from aliexpress to come in the courier... I have a 1500 watt variable frequency drive for the spindle motor, waiting also on pulleys and 4 x 80mm square radiators with fans to cool my spindle motor circulating water.
I'll pop a few photos up as I go and in my first edit to this post. The wood Gantry for the Y stage was a hard decision. I was waiting over a month for an aluminium 40 x 80mm V-slot extrusion from a local factory for it but wasn't 100% convinced it was going to provide a big enough cross section. It's on the courier now but I've already built in MDF and Ply, made it exactly the dimensions I wanted. I'll be designing again in openscad and looking at setting up a PC running Linux to try and get the only open source 3D routing program running to it's latest version. Routing only needs a very basic arduino to handle the control of the driver boards, an arduino is much better suited to accurate step pulse timing than a PC's printer port!

[TomW]

I bought an Ooznest 1000 x 1500 Workbee. Not fully set up yet.
Be interesting to follow your progress.

[thewindego]

I have my eye on the workbee as well.

[plummet]

Fucken awesome. What's the approximate cost to set this up? Heavy you looked at the price of a small cnc router? Do you have a perforated vacuum table for sucking the work down.?

I too have been thinking about such a build.

Ps if you need and steel/alloy parts cut out of sheet give me a holla. I have a access to full engineering workshop including laser and water jet and can do some good deals.

[downunder]

Good stuff.

Love your enthusiasm

How many boards you're planning to build tho?

Because once is not a hobby....

[SaulOhio]

Mine is an Inventables X-Carve. I thought it was pretty big at 750 X 750. If I want to make molds for entire boards, I will have to do them in multiple pieces. I mostly use it for hydrofoil molds. Its also useful for drilling holes in screw inserts.

What material are you going to cut your molds out of?

[fluidity]

Fucken awesome. What's the approximate cost to set this up? Heavy you looked at the price of a small cnc router? Do you have a perforated vacuum table for sucking the work down.?

I too have been thinking about such a build.

Ps if you need and steel/alloy parts cut out of sheet give me a holla. I have a access to full engineering workshop including laser and water jet and can do some good deals.

Hi Plummet,
I think cost is working out around $1600 NZD or about $1030 USD. So far there's no import tax because I'm keeping everything under the $400 NZ limit.
No vacuum table, I used to have one I made for vacuum moulding my RC Jetboat designs but I solved that design challenge and moved on... I'm going to use sticky sheet instead and try high density foam for my moulds.
I wanted to do it big enough to be able to just fit a tandem kiteboard size, though I'd probably have to build a moulding perimeter if I actually did do one that big.
I've had everything moving individually. I tested the x stage movement and I've used a setup with double X stepper motors feeding T5 toothed belt between pulleys mounted on the bottom stepper motor bolts to force around the stepper motor pulley.
I'm not happy with my Z stage that I bought, It's carrying over 4KG of spindle motor and the C section V-slot carriage I bought uses some sort of plastic covered pulleys. Felt ok testing initially but under load it was loose. I tightened it and ran through a few cycles and it got worse. So I'll investigate metal pulleys and see if that cures... else I'll need a better pair of rails. The Gantry that moves on X rails and holds the Y axis seems fine though. I used good quality sliders on my Y rails and my wooden gantry is very firm after glueing ply and MDF into a C section with the end MDF sections keeping it all in shape. This is probably a better Z stage: https://www.aliexpress.com/item/3300484 ... da119cda10

[fluidity]

Downunder and SaulOhio: I also will have the opportunity to cut cross sections, long sections for formers for old school building, to machine marine foam like Gurit M-core directly, cutting T-nut holes, cross-bleed slits for resin and 3D gripping water channels while the material is still flat. So it should be a real game changer. Biggest issue will be setting up my workshop with space for all my tools and work areas!

I did consider a smaller CNC machine but I was concerned about alignment on assembly, I like the idea of being able to work on full kiteboard sized sheets and blanks.


On a different note, has anyone spotted the newish? induction foundry gear on aliexpress and likely other places too?
Basically they use a power supply with windings set to produce only in the region of a volt or so but at 20amps+, running through a water cooled copper pipe coil. The coil stays cool but inside the coil you can soften steel and melt other metals using a graphite crucible. So next time you want small sized custom metal, it's an option. Also there's the lost wax method used on PLA 3D printed pieces, encase in a ceramic slurry, cure, melt and burn out then fill with molten metal, cool, crack open.

Here's a bit of an update, Got my water cooling running finally and tested out the spindle motor. Runs nice and quiet, also the 4 fan radiators (80mm square) are quiet running. Nothing like the noise of an air cooled router!

After the above photos I made brackets to hold the spindle motor drag chain, cables and water cooling but I'm still not happy with it. I was going to get a Z stage with wheels to slide over bars, but I'm now looking at the ball bearing sliders instead, I think the dust seal is important after having run a bit of plastic under the spindle motor routing bit, there's going to be sawdust/plastic/metal swarf everywhere when I have this running...

Exciting times!
My machine will now complete a homing run. If you look at the newest pics, you can see an x cut into the ply. Simple gcode commands, G0 X-800 Y325 goes to the centre. Most promising software so far seems to be visualcadcam 2019 which is freeeee... I've yet to convert a 3d stl object to a gcode cut file but stay tuned...