Comments sought on new build: A CNC Router for RC Gliders and Planes

[njhussey]

Thank you!!

Yes shed is 2.4m at the apex and just over 2m at the sides. This is 1.8m total height....also got double doors so can get it in and out again...

[kingcreaky]

also... dont get stung like i did initially on the accessable area... remember you have lots of wasted accessable area at the top of your machine... where you could perhaps extend the bed or add a vice etc... and there is a void of unaccesssable space at the bottom...

[njhussey]

I was thinking about that earlier. I was going to shorten the bottom and put a vice on but then decided to reverse the Y axis to stop chips from collecting on the ballscrew and bearings. Don't fancy having a vice at the top but might shorten the bed and make provision for a 4th axis.

The cutting area I was aiming for was 1000mm x 500mm and this just about gives me this so was going to leave as is but you've tempted me to have another look

[JAZZCNC]

Ok here's things I see with this and learnt from mine being vertical.

The Machine frame, (not holding frame) needs much more bracing esp at the open ends. The 2 short uprights will flex if not braced well, triangulate much has possible.

Chips which fly up will collect in several places on way down so think about covers or deflector guards. Collection areas are:
#1 Against the rails on Y axis so on the top side just in front of rail with enough clearance for bearing to slide by put a short angled deflector/catch plate which they hit first and slide off.

#2 The Ball-nut mounts so again some form of angled deflector plate wrapping over the mount with hole for screw to pass thru, won't hurt to build in a wiper seal has well. Chips don't collect so much on screw but they do around the ballnut where screw enters on top side so this is the target area to keep chip free.

#3 The bottom bearing mounts.! Same deal just some form of deflector guard so chips hit that first and bounce off.

#4 THE BIG ONE . . .Complete Z axis cover needed FROM THE START. While turning 180deg you have lessened the chip collection points BUT they will get in there and the ONLY way is full cover. They are easy made with thin Ali plate and weigh nothing not the prettiest things but very affective. Something Like this


Also while turning 180deg helps keep chips off rear of front plate it will also make it very awkward for when your changing tools.? The way you have it When doing jobs with several tools you'll have to lower gantry to reach spindle properly and that will mean leaning over gantry so will be very awkward.
Much better to raise gantry and access spindle from below, I have my screen setup with tool change position where gantry goes to top and Z axis parks in centre of gantry. This brings me to #5

#5 Not chip related but relates to parking the machine when not used. You want to build in some bump stops at the bottom and when not using park it there to release any tension on motors/screws/belts etc.
On my machine I just have some thick rubber dougnuts with slit in which slip over screws and sandwich between bottom bearing mount and ballnut which i slowly drive upto, simple but affective.! . . But if was building from scratch like you then I'd build in some permanent bump stops, either fixed or flip up jobs.?

#6 Not a biggie but still worth doing else it will annoy I'm sure.?. . . Put the side covers on the inside of frame not outside has again chips will collect and build up, have the inside walls smooth and uninterrupted and chips will slide nice into box below.

That's it for now if spot owt else i'll shout. .Lol

Edit: All the above with exception of beefing up frame work are Minor things and even if left uncovered won't affect machine working properly just annoying and over time will cause premature wear which is easily avoided with simple deflectors or covers.
Don't necessarily need to cover every thing just deflect chips away.!!

[JAZZCNC]

Said I shout up if seen anything else, well I have. . Lol

Looks like you are thinking to use the slotted front gantry style.? Well the way yo have it now it will eventually fill up with chips. .. Doh.
. . Even with brush guards they will get thru.!

The slotted gantry is great because it keeps every thing neat tidy and protected and it will work perfect turned other way just not this way. . .Sorry.!