Rauno's CNC router

[Rauno]

Hi, CNC enthusiast!

I would like to start with the reason why I started this thread. I started designing my first CNC router and googled like crazy to reach the best possible design. I felt I am quite at the optimal point already and thought about starting to ordering parts. Actually I already ordered one motion parts kit, and then I found this forum, specifically the DIY routers section and all the hell broke loose. I realized I have a lot of research to do.

So thanks to everyone for sharing their builds in this forum!

My goal

I would like to build a quite universal CNC router, so I could cut aluminum, wood, plastic. I know universal things are very good for nothing, but I would like to try to make the best out of it. I don’t want to make (small scale) series production. My main interest is to make prototypes, both functional and aesthetical. Therefore a rigid design is a must for the machine in order to make nice looking aluminum parts.

Current design

Size: Rail lengths 1000x1500x400 mm. Maybe it’s reasonable to make the router smaller so it could be more rigid with same ball screws and frame design. The 1500 mm could be changed to 1000 mm for example. Mainly considering this due the lower price of 1605 ball screws.




Custom parts (plates): Surface milled (mainly 20 mm) aluminum plates, I plan to order water cutting of the parts. Where needed I could make counterbores for the hex socket bolts using special counterbore drill.

Base frame: Rectangular tube steel, design is yet not final. I am able to weld it by myself.

Gantry beam: 4080 aluminum profile with sheet metal reinforcement. I know the 45x90 design recommendation, but it would cost me 60€ more, yet I am open to your opinion - is the 45x90 L design gantry worth this money?



Linear rails: HGR20

Ball screws:

Two options:
X, Y, Z 1605
X, Y 1610 or 2010 and Z 1605

1605 ball screws are cheaper 400€ for all axes. If I go for the 1610 or 2010 it would cost 300€ extra for me. The numbers include linear rails because 1605 are cheaper in kit with linear rails.

Few links:

HGR20+1605 kits: https://www.aliexpress.com/item/1005...3cef5171eAfjgA

1610 and 2010 could be offered mainly from BST: https://www.aliexpress.com/item/3288...25355885%22%7D

Spindle

2.2kw water cooled + VFD

Motors:

Lichuan LCDA86H+LC60H21 Set of 4 500€ from Aliexpress https://www.aliexpress.com/item/1005...08626891%22%7D

Do I need that expensive motor+driver for Z axis?

Belt drive: HTD 5m closed loop timing belt, pulley size 20T

Controller:

AXBB-E running UCCNC

Power supply:

230VAC for VFD
230VAC -> 55VAC toroidal transformer for drivers

If I understand correctly the toroidal transformer could power those VAC capable Lichuan drivers directly with AC current. One thing to consider is the input grid voltage, as my place has solar panels and this could cause bigger voltage fluctuations than the grid itself has.


I am open for comments, suggestions. Main questions are:

1. If I continue with this size is it reasonable to use 1610/2010 ballscrews for Z and Y axis. Is it worth the extra 300€. And if I don't spend extra money should I downsize the router?

2. Is the gantry stiff enough?