Thread: New CNC build

Originally Posted by Lappa

... I decided to stick with the CNC as I would need to invest in a 80W plus CO2 laser if I wanted to seriously cut as well as burn images. ...

Is this an either/or decision, Lappa, or can you keep your options open? Run with the CNC and then later, perhaps, consider adding a laser.

I have been thinking along the same lines for quite a while, so I shall be watching with interest.

The CO2 laser would have to be a completely new build. I did buy some excellent plans from a guy in NZ. It could be a lighter build with wheels and timing belts as you have little force on the axes and its fast.
Thinking at the moment is to use a laser purely for imaging so the cheap Chinese 3018 set- up works fine for wood which is what I would use it for.

Diode lasers are starting to get more powerful, I can see them getting up to 80W over the next couple of years

Originally Posted by Camelot

Diode lasers are starting to get more powerful, I can see them getting up to 80W over the next couple of years

Maybe but at the moment it’s just laser stacks. Commonly available individual diode lasers (not fibre diode lasers) are a max of 5.5W. They add more individual lasers in the package and bounce them off mirrors then through a single lense. Max at the moment is 4 lasers so 22/24W. When you see 40W diode lasers advertised, that’s their input power e. 12v x 3.4 amps.
Sure there are industrial units such as the Jenoptik that output up to 275W but we are talking 400 to 500 amps and $ 10s of thousands.
Cheap 80W CO2 lasers are about $3500.

Aah! What would those of us with small sheds do without a saw table to convert to an assembly, paint and whatever else table. It really is the go to larger flat surface in the shed, we'd never get anything done without it.

There is an alternative that sits between individual diode lasers/arrays and CO2 - fibre lasers (I work in photonics......)

Uses a diode laser as the pump, and a length of doped optical fibre to apply a (substantial) gain and give very high output powers.

Fibre Lasers - Working Principles, Applications & More | Fractory

If you Google fibre laser, you'll find quite a few at moderate powers (50W-100W) at very reasonable prices, but output powers up to several kW are available.

Originally Posted by Mr Brush

There is an alternative that sits between individual diode lasers/arrays and CO2 - fibre lasers (I work in photonics......)

Uses a diode laser as the pump, and a length of doped optical fibre to apply a (substantial) gain and give very high output powers.

Fibre Lasers - Working Principles, Applications & More | Fractory

If you Google fibre laser, you'll find quite a few at moderate powers (50W-100W) at very reasonable prices, but output powers up to several kW are available.

When looking at lasers I did look at fibre lasers but the only “hobby” fibre lasers I could find only worked on very small areas ( looked like an desk lamp) and cost around $5000 to $7000. Most of these were used for “etching” only; no cutting which is the advantage of CO2 lasers IMO.
Are there units that can work like a CNC on eg. a 3018 or larger platform?

Travis Mitchell over on the youtubes has built a very nice Fibre Laser for around US$15000 all in - includes the moving parts, fibre laser, cooling and gas supplies.

His patreon is pricey, but it has everything you need to duplicate his work.

DIY 1000W Fiber Laser Cutter Part 1: Project Introduction - YouTube

I'm keen to add something similar to my AvidCNC at some point, but controlling the laser with my warp9 setup is a bit of an issue, and possibly beyond my limited smarts...

Originally Posted by Bernmc

Travis Mitchell over on the youtubes has built a very nice Fibre Laser for around US$15000 all in - includes the moving parts, fibre laser, cooling and gas supplies.

His patreon is pricey, but it has everything you need to duplicate his work.

DIY 1000W Fiber Laser Cutter Part 1: Project Introduction - YouTube

I'm keen to add something similar to my AvidCNC at some point, but controlling the laser with my warp9 setup is a bit of an issue, and possibly beyond my limited smarts...

Had a quick look at his video but his machine seems to rock about a bit, however I would love that sort of ability.

Good to see you take the plunge Lappa.
Looking forward to seeing the design.

Unfortunately, I didn't take a lot of photos during the second half of the build.
Chris, the guy that machined the plates, also included 5 perfectly machined and drilled spacers so you can attach Delrin anti-backlash lead screw nuts to the plates.

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I prefer these on my lead screws. Even on my cheap 3018 unit, I replaced the brass, spring loaded units with these blocks

On the Z axis plate of my new build, you can actually attach two Delrin blocks which is great due to the added load of the spindle and the heavier stepper motor I used for the Z axis.

Speaking of lead screws, lead screws and grub screws are a marriage made in hell!!. To stop movement, where ever a grub screw contacted a lead screw, I machined a flat and locked the grub screw with Loctite.

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The base machine mechanicals were completed a few days ago and it looks great (IMO) and feels rock solid.

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The spindle mounts arrived and I added a spoil board - 16mm MDF and the cable chains - postioning to be finalised when cables are added.

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While waiting for the cables, I got on with building the electricals. I was lucky that I found a steel cabinet (used for an electrical control board going by the lights and switches) in a scrap steel bin so I grabbed that. Electricals are mounted on plywood.

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I'm using an Arduino UNO and running with the UGS software.

There is a 36v power supply and a 5v/12v power supply, In the second photo, the blue unit on the right is an opto-isolator board that you attach the limit switches to.

The orange unit in the first picture is a brilliant latching relay - brilliant because it can work on voltage ranging from 12v to 250V, AC or DC and can handle 16amps. It can be configured so a single momentary switch can turn it on with one press then off with the next press or use two momentary switches - one for on and the other for off. It is also NV sensitive.

Wiring layout is critical to reduce/eliminate electrical interference so I've followed advice from a industrial CNC builder.

I will tidy up the wiring when all is in place.

I did a trial run, just running standard wires from the drivers to the steppers - no limit switches yet, and it ran a program without a problem.


Shielded steeper and limit switch cables arrived so I spent today wiring those to the machine.

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I still need to add the stepper and limit switch sockets to the case, add the limit switches, emergency stop switch, add plugs to ends of cables then add more sockets for the zeroing probe, reset/abort, cycle start/resume and feed hold switches, etc. etc.

That's all for today.

Wiring in the control box completed and wiring to the stepper motors completed. I tried to use mini Molex connectors but gave up. Out of interest, I priced a genuine Molex terminal crimper for their small terminals - $1250!!!!!!!!!!! from RS.
In the end, I scrounged some used computer hard drive power cables from a computer shop and used those - came up a treat.

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All the connectors are fitted to the back of the control box - five pin ones for the steppers so I can run the shield wire to the 240V power earth and 4 pin for the limit switches for the same reason. Couldn't buy 3 terminal so I settled for 4. Still needs to be prettied up and nicely labeled.

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Playing around with positioning for the limit switches but I think I'll settle with these positions.

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All are adjustable to I can fine tune them.

One of the failing of the plates I bought is that the front plates are suited for a CNC running on wheels. When you add the linear rails, the whole gantry will slide right off the front!!.

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I added these stoppers which also act as the limit switch end stops so all's well.


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Checked the actual movement dimensions and its 435 x 435mm so happy with that.

Checked movement accuracy and its fine.

Check for squareness in all directions, including Z axis (which needed some adjustment).

On setting up - Z axis is set on 1/.2 step ie. 400 steps per revolution which will reduce the accuracy somewhat but gives me torque which is important with the heavy stepper and Makita router it has to carry. X and Y axis are set on 1/4 step or 800 steps per revolution.
I have played around with speed and acceleration and at the moment I have settled on 5000mm per min for X and Y and 1000mm for Z re speed. Can't remember accel figures off the top of my head but all these figures will get fine tuned once the limit switches are operational.
This was a good workout as I needed to tighten the lock collars harder against the bearings. Thinking of adding some tensioning nuts on the Y axis but it would mean new lead screws and the wallet's taken enough of a beating at the moment

Ran an air cut program to cut a shape and ran like a charm - very happy.

Waiting for M2 screws to arrive so I can finish off the limit switches.

Cut some holes in the table and added a cable enclosure to neaten the cabling.

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Still work to do but its getting there.

Interested in your build. I was involved in building a large CNC router 2400 x 1200 which has been in use for some time. The drawback is there are only three members who use the CAD program and run the machine.

What software do you intend using and where are you sourcing the bits?

I built this a while back...and sold it.

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