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

[njhussey]

OK Chaps a couple of questions if I may. I'm rapidly pulling all the bits together and just want to check that I'm not going to start this build and then just when I get going come to a grinding halt because I've overlooked something! Below is a list of what I have and what I think I still need to get. Can you take a look at it and suggest what else I've forgotten please?

Items already purchased
• 1000mm x 800mm x 20mm Aluminium Plate (eBay)
• 2200mm x 950mm x 10mm 6082 Aluminium plate (eBay)
• X axis 20mm NSK linear rails 1300mm long & 4 carriages (eBay)
• Y axis 15mm THK linear rails 750mm long & 4 carriages (eBay)
• Z axis 15mm THK linear rails 440mm long & 4 carriages (eBay)
• NEMA 23 3Nm steppers x 3
• AM882 drivers x 3
• PDMX 126 BOB
• X axis ballscrews x 2 1325mm long with Ballscrew, ballscrew housing and Fixed and floating end bearings and housings (Chai)
• Y axis ballscrews 750mm long with Ballscrew, ballscrew housing and Fixed and floating end bearings and housings (Chai)
• Z axis ballscrews 415mm long with Ballscrew, ballscrew housing and Fixed and floating end bearings and housings (Chai)
• 1 set of ER16 collets 2mm through to 10mm (Chai)
• 2.5m of IGUS 15 series 36mm x 24mm energy chain (eBay)
• 6 off mechanical limit switches (also have 6 off PNP Proxy switches in case I want to use them instead of mechanical switches) (eBay and cou”work”gh)
• E-Stop button
• Homemade 1.7kW brushless outrunner spindle (Me!!)
• 100mm x 50mm x 4mm 7.5m length of steel
• 50mm x 50mm x 4mm 7.5m length of steel
• 50mm x 25mm x 4mm 7.5m length of steel
• 24V 47A (twin server PSU’s) PSU for the spindle
• 75A ESC & Servo tester for the spindle

Items to be purchased
• PSU (parts as will make one)
• CY cable (will ask our works electrician if he has any going spare…)
• Cable Tray (as above)
• 5mm pitch HTD Pulleys and belts (lengths of belts still to be fixed)
• Bespoke Z axis Ballnut mount (one of you hopefully??!!)
• Epoxy for levelling the X axis rail beds
• Spindle mount to be machined (again one of you hopefully??!!)
• Various size taps for tapping all the holes

There are more bits that I think I need but at the moment I can't think....that's where you experienced chaps come in

[JAZZCNC]

There are more bits that I think I need but at the moment I can't think....that's where you experienced chaps come in

Hundreds of nut's & bolts and Screws.!! . . . . Kid you not 200 bolts go no where.!! . . . DONT buy cheap taps and get spiral flute they make life easy.

Good electrical cabinet to put it all in and trunking to separate power and signal cables etc.

Now start building and stop over thinking because you'll never account for everything and plans will change has you go along.!!

[njhussey]

Hundreds of nut's & bolts and Screws.!! . . . . Kid you not 200 bolts go no where.!! . . . DONT buy cheap taps and get spiral flute they make life easy.

Good electrical cabinet to put it all in and trunking to separate power and signal cables etc.

Now start building and stop over thinking because you'll never account for everything and plans will change has you go along.!!

I'll get some more spiral flute ones Dean!

I'll ask our electrical engineer to get me a cabinet, probably a Sarel one as well as the trunking...

Will be starting the frame once the steel gets here which hopefully will be in the next day or so. Will get it cut up before work and at lunch and then start the welding bit by bit. Can't do it at home as no 16A sockets :(

[JAZZCNC]

Can't do it at home as no 16A sockets :(

Just bang an old nail in fuse it'll be ok for a few hours welding. .

[njhussey]

It's one of them new fangled fuse boxes with little plastic trippy things so you can't wrap tin foil round the fuse or bang a nail in.... :(

[~andy]

Got an electric oven? That will probably be on a 32 amp radial. I'm clearly not suggesting you pop the isolating switch off the oven and have the wire running out of your kitchen window. That would be irresponsible.

[njhussey]

Andy, for a nano second I did think about it ;) .....however I'd have to have some sort of beefy extension lead going to the shed as it's a good 15 meters away from the cooker! I did think about getting a 5.5kv genny too but the cost was too much as I'd not really use is and its a new build so all the houses are crammed together so the neighbours would complain... simple solution is that I'll weld it at work, we have all the kit as it's what we do here!

[Jonathan]

What's special about the Z-axis ballnut mount that causes you to need a custom one?

The PSUs you've got for the spindle sound good. Do you have a source for them for a reasonable price?

[njhussey]

What's special about the Z-axis ballnut mount that causes you to need a custom one?

These are what I've drawn...

I wanted them low profile to cut down on the machining required, i.e. so I don't have to get the Z axis plates machined for clearance and so I can get the rails nearer together which I know is not ideal but as I'm mostly going to be machining balsa, ply and carbon fibre will be fine!

[Wobblycogs]

They look very similar to these (which I'm planning to buy): Aliexpress.com Ball Nut Housing.

If anything I'd say they are lower profile than the one you've drawn up. The bottom bolt holes are in slightly different places but I'd be surprised if that was critical.