Needs Pictures: 0
Results 1 to 15 of 47
Thread: New CNC build
-
13th March 2023, 05:18 PM #1Woodworking mechanic
- Join Date
- Jan 2014
- Location
- Sydney Upper North Shore
- Posts
- 4,472
New CNC build
I’ve been threatening for years to purchase a CNC but never got around to it. I then got interested in lasers and was tossing up which one to buy. I bought a cheap 3018CNC kit with 70w spindle and 5.5W laser to have a play and see which one I preferred.
I spend some time beefing it up and in the end I could get some “reasonable “ carvings and some very nice “burnt” images. 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.
The cheap 5.5W laser does all I want re imaging so I’ll keep it for that and get rid of the spindle.
I had a look at some CNC kits available but none suited my situation. I have limited space so a 1000mm x 1000mm was out of the question. No companies I contacted would make a smaller one and basically said the cost of a small one would be very similar to a 1000x1000 unit so I decided to build my own.
The space I have is 800mm x 800mm so with stepper motor extensions etc. I can fit a base footprint of 600 x 600m. This allows for X adis stepper motor extending from the side and the Y axis stepper motors to extend from the back.
The design gives me an effective machining area of somewhere around 450 x 450mm. This is pretty good for the size of the base as most manufacturers say you lose 250mm per axis from the base outside dimensions. eg. A 1000 x 1000mm has an effective machining area of around 750 x 750mm.
Another consideration is I wanted to be able to machine soft metals so I needed something sturdy. I decided on C Beam for all axis and twin linear rails on all axis giving me a total of 8 linear rails. I couldn’t get SFU ball bearing screws to suit the length so I settled for 8mm lead screws.
I also wanted a reasonable Z axis height.
Shopping around, researching builds, talking on forums etc. led me to a guy called Chris Laidlaw in the USA that supplies a range of plates.He does all the matching to order. He had designed a set of plates that took twin linear rails on all axis and he could supply 11” high Y gantries over 7” or 9” that were also available.
So in went the order.
While waiting for that I ordered to aluminium, fasteners, brackets etc from Melbourne and the linear rails, bearings and lead screws from Aliexpress (prices in Australia were double and most likely came from the same place).
Part 1
Base assembly
D0C43EF2-8B60-419F-AEAC-1C9868FDA0A5.jpg
Brackets were added to fasten down the spoil board.
Linear rails added to Y axis C Beams
9D777A31-E630-4D8E-9990-A91B6B67B6BE.jpg
The linear rails came with one bearing, so I had to order 8 extra bearings so there would be two bearings per rail.
I had read some dreadful stories re quality of Chinese linear rails and bearings but these were excellent. They were cleaned to remove the packing lubricant then re lubricated with EP1/EP2 grease.
Aligning the rails.
3D7A70C3-4161-4508-86CC-101857721F9E.jpg
The top rails was aligned from the top then all top screws tightened. The Botton rail was left slightly loose then aligned when the gantry was attached by sliding from front to back repeatedly then tightening the screws.
.
Y gantries mounted
A0652C52-D9C2-43DF-BEFB-4BA505D4E900.jpg
Word of warning
Using two rails seemed a good idea at the time but slight variations in the C Beam or linear rails led to the movement tightening when the bearings were attached by screws to the plates. I ended up buying shim steel in varying thicknesses and shimming between the back of the bearing and the plate ,on some bearings. Tedious, but the result was good
Part 2 to follow.
-
13th March 2023 05:18 PM # ADSGoogle Adsense Advertisement
- Join Date
- Always
- Location
- Advertising world
- Posts
- Many
-
14th March 2023, 03:52 PM #2Originally Posted by Lappa
I have been thinking along the same lines for quite a while, so I shall be watching with interest.
-
15th March 2023, 09:14 PM #3Woodworking mechanic
- Join Date
- Jan 2014
- Location
- Sydney Upper North Shore
- Posts
- 4,472
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.
-
15th March 2023, 09:21 PM #4
Diode lasers are starting to get more powerful, I can see them getting up to 80W over the next couple of years
-
16th March 2023, 10:15 PM #5Woodworking mechanic
- Join Date
- Jan 2014
- Location
- Sydney Upper North Shore
- Posts
- 4,472
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.
-
17th March 2023, 09:38 AM #6GOLD MEMBER
- Join Date
- May 2011
- Location
- Albury
- Posts
- 3,030
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.
-
17th March 2023, 09:50 AM #7
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.
-
17th March 2023, 05:18 PM #8Woodworking mechanic
- Join Date
- Jan 2014
- Location
- Sydney Upper North Shore
- Posts
- 4,472
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?Last edited by Lappa; 17th March 2023 at 05:40 PM. Reason: Additional
-
17th March 2023, 06:11 PM #9GOLD MEMBER
- Join Date
- Nov 2018
- Location
- Newcastle
- Posts
- 1,018
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...
-
17th March 2023, 07:38 PM #10
-
18th March 2023, 08:11 PM #11Senior Member
- Join Date
- May 2019
- Location
- Sydney
- Age
- 45
- Posts
- 220
Good to see you take the plunge Lappa.
Looking forward to seeing the design.
-
21st March 2023, 08:18 PM #12Woodworking mechanic
- Join Date
- Jan 2014
- Location
- Sydney Upper North Shore
- Posts
- 4,472
Part 2 of CNC build
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.
delrin block.jpg
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.
IMG_1985.jpg
The base machine mechanicals were completed a few days ago and it looks great (IMO) and feels rock solid.
IMG_1967.jpg
The spindle mounts arrived and I added a spoil board - 16mm MDF and the cable chains - postioning to be finalised when cables are added.
IMG_1979.jpg
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.
IMG_1976.jpg IMG_1977.jpg IMG_1984.jpg IMG_1983.jpg
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.
IMG_1982.jpg
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.
-
26th March 2023, 05:33 PM #13Woodworking mechanic
- Join Date
- Jan 2014
- Location
- Sydney Upper North Shore
- Posts
- 4,472
It's ALIVE!!!!!
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.
IMG_1992.jpg
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.
IMG_1987.jpg
Playing around with positioning for the limit switches but I think I'll settle with these positions.
IMG_1988.jpg IMG_1989.jpg IMG_1991.jpg
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!!.
IMG_1957.jpg
I added these stoppers which also act as the limit switch end stops so all's well.
IMG_1995.jpg
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.
IMG_1994.jpg
Still work to do but its getting there.
-
26th March 2023, 06:19 PM #14Novice
- Join Date
- Dec 2013
- Location
- Queensland
- Posts
- 11
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?
-
26th March 2023, 06:33 PM #15SENIOR MEMBER
- Join Date
- Dec 2017
- Location
- Aldinga Beach
- Posts
- 478
I built this a while back...and sold it.
cnc1.jpgcnccontrol2.jpg
Similar Threads
-
Round table build question (and build)
By LickinChips in forum FURNITURE, JOINERY, CABINETMAKING - formerly BIG STUFFReplies: 3Last Post: 12th September 2021, 08:22 PM -
Outdoor Table Build - full build photos
By pach in forum FURNITURE, JOINERY, CABINETMAKING - formerly BIG STUFFReplies: 6Last Post: 25th March 2019, 05:18 PM -
Plan the build / Build the plan. Verandah steps & Trim
By Charlee43 in forum WOODWORK PICSReplies: 4Last Post: 22nd March 2014, 07:28 PM -
Patio build - Hardwood and softwood in the same build?
By gidgegary in forum WOODWORK - GENERALReplies: 1Last Post: 16th January 2014, 09:00 PM -
help me build a basic flat build bed trailer for my kayaks
By gros21 in forum TRAILERS & OTHER FABRICATED STUFFReplies: 7Last Post: 13th October 2011, 08:47 AM