Some time ago, in great excitement and anticipation, I bought one of those '3018 desktop cnc mill' machines from somewhere, but I never assembled it... until now.
(in case you're wondering, I bought it, then fell ill, and by the time I had fully recovered, there were other projects on my mind - this thing sat on a shelf, gathering dust)
The thumbnail? Why yes! I love This Old Tony! / @thisoldtony
The machine I have is something very similar to this one: www.banggood.com/Offline-Vers...
If you're in the same predicament as I was (i.e: you have the machine, but no instructions), Here's how I recommend to assemble (after unpacking and cleaning away any metal swarf like mine had inside the protective film):
Identify the key parts:
The base will be constructed from the two rectangular-section metal rails, plus the two long thin black plastic pieces (note these have small protruding feet on the bottom edges), plus the shorter set of linear round rods, plus the shorter of the two threaded rods.
The gantry will be constructed from the two square section metal rails, plus the other two plastic pieces, plus the longer linear rods and threaded rod
The bed comprises the silver metal plate (the side with 3 slots is the underside) and the grey linear bearings and screw carrier
You will have two different lengths of M5 machine screws:
Shorter screws: for attaching the linear bearings to the machine bed
Longer screws: for assembly of the rest of the structure
Sequence of assembly (based on my trial and error - rationale further below):
1. Assemble the linear bearings and screw carrier onto the underside of the silver bed plate - put the screws through the holes, loosely fit the large channel-nuts, then slide the parts into the channels and tighten them finger-tight
2. Assemble 3 sides of the base - take the long plastic piece with the large central hole and bolt through it into the ends of the two rectangular-section metal rails
3. Take the two plastic gantry support pieces and affix them to the outside of the two metal base rails (the support with the large circular hole goes on the right side) - bolt through the holes and add the small channel-nuts, then slide these carefully into the channels on the base sides, then tighten finger-tight
4. Add the front of the base, bolting through into the two side rails
5. Turn over the assembled machine
6. Thread the two linear rails through their bearings on the underside of the silver bed plate, then fit these rails into place in the frame of the base (bolting into the ends of the rails through the holes in front and back of the base
7. Feed the shorter threaded rod through the hole in the back of the base, screwing it through the screw carrier, adding the spring and brass anti-backlash nut as you go through - keep driving this rod until it goes into the bearing on the front rail
8. Add one of the coupling cylinders to one of the stepper motor shafts, then fit this motor to the back of the base, coupling it to the threaded rod. The connector plug for the motor needs to be oriented so it will be on top when the machine is the right way up
9. Fully tighten the bolts holding the linear bearings on the bed plate
10. Turn the assembled machine right side up
11. Push the longer linear rails rods through the Z axis assembly and fit these rods in place between the gantry supports
12. Add the long threaded rod through the Z axis assembly, via the larger hole in the gantry support (adding a spring and anti-backlash nut)
13. Add the stepper motor to the right gantry support, coupling it to the end of the threaded rod
14. Add the two gantry structural rails between the two supports. Slide two of the small channel nuts into each rail before you do this.
15. Slide the gantry so that the spindle motor will be exactly halfway between the front and back of the base (most photographs of the assembled machine show this nearer the back, but that's wrong). Fully tighten the bolts holding the gantry supports to the sides of the base.
16. Add the spindle motor
17. Bolt the PCB to the back of the gantry rails, using the plastic standoffs, and bolting into the channel nuts you added in step 14. Don't overtighten these.
18. Wire up the stepper motors and spindle motor
19. Double check all structural bolts for tightness
Rationale for this assembly sequence:
Channel nuts in the structure need to be slotted in while there is still an open end of the channel
Channel nuts in the bed plate are really hard to engage with the bolts if you try to do it after fitting the bearings to the rods
If the stepper motors are fitted before the threaded rods, it's really hard to get the threaded rods into place
The gantry structural rails just get in the way if they are added too early.
5 фев 2021
