25/24

Title

CNC Repairs and Upgrades https://wiki.norwichhackspace.org/index.php?title=CNC_Machine

Proposer

Helen

Date proposed

7th October 2024

Date for Decision

Approved in principal, discussion on details ongoing

Cost

Estimated Cost
£100 would cover most upgrades
Controller and Laptop and enclosure if necessary extra.
Running Cost £57.38
£6.40 - copper pipe for eccentric clamps (1)
£6.95 - longer shielded USB- USB B cable (5)
£14.03 - z-probe (7)
£29.99 - emergency stop (9). Most expensive item so far, but most important for safety. Can also be used for other machines if ad-hoc emergency stop required.

What is being asked for

This is an evolving list, and items will be marked as completed, in progress, not started or abandoned.

Changes may be made to any of the list items, and new items may be added on.

The list is in no particular order; some are things that I (Helen) am intending to do soon or are urgent.

Some points are stretch tasks/ nice-to-haves.

Competency (may use multiple colours if I have not looked into what is involved in the process)

• Green - I am confident that I am competent to do this myself
  

• Orange - I can’t currently do this, but I think I should be able to with a little research or advice
  

• Red - I need to do extensive research to do this or some help from a more knowledgeable person
  

1. Dog Hole Eccentric Clamps

Green

In progress, essentially complete.

I used this design for the modified eccentric clamps. Materials & resources used - length of 15mm copper pipe (£6.40), plywood scraps from the laser room box, laser time

I am making/ intend to make 2 kinds of clamps, most of which will consist of scrap wood. This will hopefully minimise damage to the CNC and cost when collisions occur. This design https://www.youtube.com/watch?si=2aUY7xtjrpurt9U1&v=O-rqf4uSXRE&feature=youtu.be

Progress:

Dog holes installed in the spoilboard, clamps glued yesterday, initial test positive. Made a mistake with the depth when surfacing after the dog hold cutting, work area 1 mm below rest of spoilboard. Unfortunate, but livable, can flip spoilboard over if needed. I have made the dog holes, and a set of the eccentric clamps. They work well, but I need to laser cut some more so that I can clamp thicker pieces of wood (currently have 6-12 mm thick clamps). The copper pipe used may deform over time, so replacing with aluminium bar at some point may be a good move.

2. Add bolt holes to hold nuts for hold-down clamps

Green

In progress

Considered adding slots to spoilboard to utilise t-slots on aluminium base, but decided against this for ease and to avoid damaging the base in case of collision with head. I intend to use roofing nuts due to the low price point (approximately £0.05 per nut in Thorns DIY, likely cheaper elsewhere), though other but types (wing nuts, T-nuts) would work too. I’d require approximately 54, at a spacing of 75mm per hole, to alternate with the dog holes, plus some bolts (think there’s plenty in the workshop) and some plywood scraps to make the hold down clamps.

Approximate cost £3-5 depending on type of nut used/ scavenged.

Progress

I flipped over the spoil board and found approximately 100 pronged T nuts in the existing spoil board. I removed them, and have been able to reclaim approximately 80. I will replace them in appropriate positions and purchase botls for the nuts. I believe the nuts were M5, but I will re-check this prior to purchase

3. Bit and collet holding tray/ board

Green

In progress

Will make on the CNC from whatever scrap wood is in the workshop.

Progress

I have measured and counted the collets, and have designed most of the holder.

4. Clamp and spacer holding box
'Green
Not started
Will make from scrap wood

5. New shielded cable for controller to laptop
Green
Complete

The only filtered USB B to USB cable in the hackspace is 1m long, which really restricts where the laptop can be. Non-shielded cables disconnect mid- pass quite often £5-10 including postage.
Completed
Purchased and used. More range for controlling laptop. Still some disconnections, but better than when using non-shielded cable. Cost of £6.95

6. Sort out the MacBook
orange

I couldn’t get UGS to install on it a few weeks ago - can’t remember what the problem was (possibly required an administrator password?) I’ve been running everything on my own laptop. I’d also like to get a copy of Fusion360 or FreeCad or something on there. I know very little about MacBooks, so this may be annoying, and I may have to work out what the administrator password is (different to the log in password written on the MacBook).
Not started
Some discussion of replacing with a new laptop.

7. Install a z-probe
Orange
In progress

Found one on Ali Express for less than £2, but the ones with a recessing touch plate seem to be £10 -15. A / pressure gauge might be a good teaching tool and save some broken bits. Little more expensive, starting at £30 once you include postage.
Progress:
Probe purchased at a cost of £14.03 awaiting delivery

8. Print an adaptor for the vacuum & brush attachment
Green
Not started

The size worked for the big vacuum in the main workshop, but that is out of reach in the sanding room. I’d like to print an adaptor or a new attachment to work with the sanding room vacuum. Cost - some FDM filament

9. Emergency stop for the spindle
Orange/ Red
In progress
Certainly the biggest safety issue. Either tie spindle into existing switch or set up second emergency stop button. Cost - potential new emergency stop switch. Ben (Plexer) will look over the control board with me to see if the existing stop can be wired in to work for the spindle.
Progress:
Barney suggested an in-line stop button, at a cost of £30. Benefit - can easily be used for other mains-powered equipment if needed. Plexer has confirmed that the spindle cannot be wired through the existing stop button. Purchased for £30, awaiting delivery

10. Work out why CNC doesn’t seem to register end stops
Orange
Not started
This probably involves looking at the control board. I’m not sure what is involved, may be able to figure it out. Cost - potentially new end stops.

11. Mist coolant system
Red
Not started
Nice-to-have. Can be set up for just air or air and coolant. Lubricates plus helps to blast chips. Found a guide here. Cost £20ish plus an air compressor

12. -Re-organise space around CNC
Green
Not started
So that it does not hit the wall and is easier to use. Maybe move belt sander to allow operator to sit at the end of the CNC for easier interpretation of axis and greater safety.

13. Review current stock of bits and collets
Green
In progress

I think there may be some bits that we don’t have a large enough collet for. Fill any major gaps. Variable cost.

Cost - variable.

14. Update CNC page on Hackspace wiki
Green
In progress

Include basic details such as size of bed, clamping system, where things live. Safety risks, dust collection. Useful to add: which machine to choose from fusion library, list of available (and unlikely to break) bits and collets provided by the Hackspace.

15. Future CNC inductions
Orange
Not started

I’d like to make the process of starting to use the machine easier. This would be after sorting out the emergency stop, and ideally also the end stops.Write list of basic competencies to use the CNC safely, compile learning resources, list who is happy to induct on machine basics. There’s a lot to go through, and too much to cover in a reasonably long induction, so having a competency checklist and guidelines ahead of time would probably help. Someone who has CNC experience would be able to go straight to a machine induction (shown where things are, told about any idiosyncrasies), someone with limited or no experience would have a list of things to learn, then could be inducted in a much shorter session.

I’d also consider running a group session for people with no experience to go over the basics, signpost to some resources, and then do individual inductions once the group has gone away and learned the core concepts.

16. Swap axis to make coordinate system more intuitive
Red
Not started

17. New control board for CNC
Red
Not started
More functionality, can run FluidNC/ GrblHAL, space to add additional upgrades in the future. Discussion on control board in #CNC channel on Slack.

18. Induction work sheet
Green
Not started
Will compile details, likely after new control board & axis swap. Marion has offered to write the sheet up

19. New Enclosure
Red
Not started
The current enclosure is packed very tightly. A new enclosure would help reduce EMI (and hence the cut-out issue. Enclosures seem to be about £200 to buy a metal one (plastic are cheaper but provide less shielding). Cheaper option - repurpose old PC case. A non-working metal Apple Mac has been ide identified as a potential donor.

20. Software Options
Green/ Orange
Not started
Set up well documented & easy to use software on control laptop. Currently using UGS on personal laptop with add-in to export gcode from Fusion360 (for ease). Also using person copy of VCarve, post-processor & saving to file, then opening file in UGS.
Plexer has contacted Lightburn about getting in on the beta test for their new CNC control software. Currently not open, but are on the waiting list.
Craig has suggested getting the makerspace licence for VCarve. I have been using my copy of VCarve to make my inlays, and have found it intuitive and user friendly. The licence is £100 per year, and members will have access to a version to use at home. The big advantage would be that we could set up guideline parameters for new users to flatten the learning curve and risk of damage to equipment. https://www.vectric.com/products/makerspace/

21. Vacuum Clamp
Green
Not started
Option to convert clamping system to vacuum clamp as shown here https://openbuilds.com/builds/diy-vacuum-hold-down-table.10071/.

Why/how this will be good to have

We will be able to make the machine safer and easier to use for members. Currently, there are significant barriers to users, experienced CNC operators or not. These changes will mitigate these, and make the CNC a valuable piece of equipment.

Who is supporting the project

Helen, Barny, Ben, Dean, Alan

Comments

Advice, guidance and suggestion is being given in the #CNC channel.

Outcome

go to main page

go to proposals