Luthier CNC

[bluesking]

Minor update today as I have not made as much progress as I hoped.

Cut angles into the side plates using a table saw with a cheap aluminium blade I got from screwfix. Worked perfectly:


Started assembling machine only to realise I still have my paper templates on my aluminium plates. Started peeling these off and immediately realised using spray on contact adhesive was a huge mistake. Paper wouldn't come off. Used a Stanley knife blade to try to coax it off with limited success. Spent most of the day trying to clean the leftover gunk with acetone - managed to clean off half of one single plate (and not very well).

After dinner I realised I have lots of lighter fluid which I use for cleaning gunk off guitar finishes and tools. Thought this may be worth a try and it worked fantastically. Finished all of the plates in about 1.5 hours!

1 Douse the paper with lighter fluid


2 Leave for 1-2 mins to let it soak in and peel the paper off; dead easy


3 Kitchen roll doused in lighter fluid to gently wipe off any gunk - keep adding lighter fluid rather than elbow grease (avoids smearing the gunk around). Here are all the clean plates and extrusions ready to assemble:

[Lee Roberts]

Nice!

What table saw have you got?

I use blades by OX TOOLS (https://www.ffx.co.uk/tools/product/...6Mm-X-30-X-80T), check out FFX if your a Screwfix/Toolstation kinda shopper, service from them has been great, fast to post out to.

Toolstation have these blades as well but not quite the same size offerings, just got one of these for my circular saw as helping bro build a new workshop: OX TCT Circular Saw Blade 184 x 30 x 28T

[bluesking]

Nice!

What table saw have you got?

I use blades by OX TOOLS (https://www.ffx.co.uk/tools/product/...6Mm-X-30-X-80T), check out FFX if your a Screwfix/Toolstation kinda shopper, service from them has been great, fast to post out to.

Toolstation have these blades as well but not quite the same size offerings, just got one of these for my circular saw as helping bro build a new workshop: OX TCT Circular Saw Blade 184 x 30 x 28T

I use the Triton TWX7 with the table saw module (I have the router table module too, which sees a lot of use in guitar building)
http://www.tritontools.com/en-GB/Pro...20Systems/TWX7

Had it about a year and a half and still everything works very well and no rust - happy with it overall.

Thanks for the links - the table saw needs 245mm blades w/ a 30mm mount - the best deal I found was at screw fix for about £30.

[bluesking]

Build started in earnest:

1 Y axis rough assembly


2 Y axis ballscrew


3 X axis assembly beginning


The gantry seems to move on its rails without binding - more by luck than by any concerted alignment effort. I'm not sure what freedom of movement I should be expecting though. It doesn't keep rolling after its been pushed.

Here is a vid of it being moved by hand. Can someone please check if this looks and sounds about normal?
https://streamable.com/u1pd2

Also, I have tried securing the ballscrew nut to the gantry. This seems to work OK, but at both of the extremes of travel, the resistance does go up quite a bit. I think I need to align the ballscrew more accurately to stop this happening. I'm finding this quite difficult - is there any advice you kind folks can offer?

[Lee Roberts]

Sounds and looks about right to me, did you get the rails and bearings from fred @ BST?

I've just been setting up a bed axis lead screw and had the same problems last week, I noticed in your video that there was quite a gap between the ball nut mount plate and the ali extrusion that passes under the machine, I'd say you need to shim that gap to perfection, just take your time and have the plate screws just finger tight so you can see any movement the plate wants to do, its likely you'll need to get down to beer/coke can thickness for shim material.

Then when it looks like you've got it close, run the gantry up and down a few times, do this with the ball screw mounts just finger tight as well so they can find their natrual sitting postion, then start at the floating end of the screw with the gantry down at that end as close as it can go (with-out falling off the rails), tighten the fixings for the ball screw mount at the floating end and then run the gantry up to the fixed end and do the same, creep up on perfect alignment and the ball screw should spin effortlessly as you move the gantry, I've got my X axis (gantry axis) so close doing it this way that i can push the whole z axis assembly from one side to the other with one finger and think that's the standard to aim for on the other axis's.

You can fine-fine tune each with a dial gauge later ;-).

[bluesking]

Sounds and looks about right to me, did you get the rails and bearings from fred @ BST?

Lee, that's really useful advice, thanks a lot, I'll try to follow it. Yes, all the linear motion stuff is from BST.

[Lee Roberts]

Lee, that's really useful advice, thanks a lot, I'll try to follow it. Yes, all the linear motion stuff is from BST.

Well Fred's kit is the real deal so you don't need to worry about it being fake Hiwin linear rails and bearings, the fake stuff doesn't move as smoothly as genuine Hiwin dose, Hiwin is usually quieter as well.

Don't forget to clean them and give a few drops of oil, once everything is setup and running great you can start using Lithium 2 lubricating grease, this lasts longer.