CNC build(s) & upgrade ....saga


#1

After the excellent show n tell Tuesday, it was suggested I post some info/history, so here goes.

Couple of years ago, built a CNC using crossslide vice (against lots of internet advice - which was correct).
Did couple of serious hole drilling jobs…with lot of care & manual tweaking
But my XY axis had really bad backlash and twist.


Luckily I built to allow upgrades - 1st photo shows upgraded Z from dremel (don’t bother!!!) to $20 donated trim router
…Cuts 6mmx1mm in Al at good feed rate…but 1/4" holder =?>$$ tools, or adapter
Collet is REALLY short - so does not hold very well
…probably need upgrade/swap…
Z axis weighs 7kg!!

Next photos show items been scavenging/donated over last year, so can do upgrade


But the upgrade would now be a bed of 1000 x 1700…which means need a fairly serious CNC to make parts for it…so an interim upgrade of XY on original mill is underway to make a mill with XY of about 500 x 400 travel, that hopefully can cut Aluminium, maybe steel.


(Amr Tawfik) #2

Amaizing! Thanks for sharing!


(Stephen Davies) #3

Good to see you making progress.


#4

All 3 axis move on new rails.

X tweaked to 400mm travel and starting to tune driver and firmware settings. Going to use temporary bed to help make final parts.


(Stephen Davies) #5

Sweet :wink:


(Steve Kennedy) #6

looks great so what controller are you going to use?


#7

Started with an Arduino Pro and grbl, then mainly due to ancient Dremel electrical noise, switched to an Arduino Mega, still with grbl. Seems OK and have run some basic jobs OK (before this upgrade).

If I ever get the hardware to any sort of halfway decent accuracy/repeatability it may be worth an upgrade to a more serious controller. Currently slowed down with tweaking stuff. Could start test jobs, but really really need to work out expanding/sliding covers to keep the rails and lead screws covered first.


#8

First rough cuts in Aluminium

Seems like it might work after all.


(Stephen Davies) #9

Looks good. Can you share details on cutter dimensions, speeds n feeds?


#10

Cutter 3.5mm 4 flute spiral, HSS
Feed very slow 127mm/min …swarf was very fine. edit…Router no load speed is 30k rpm.

Was really just a rough check to see if mill would move repeatably under load. Any tips very welcome.

edit… and totally incorrect tool for cutting letters that size.


(Stephen Davies) #11

Hi,
thanks for that. My last attempt was using the cheap 3.18mm, 2 flute, pure carbide cheap chinese bits. Spindle runs at 33k RPM. Was breaking bits at 800mm/min. Will try 200 and see how I go.


#12

Initial cutting highlighted the need for dust covers which I had been delaying…super fine Aluminium swarf/dust (see 1st photo below) is really not good for linear rods, bearings and lead screws…

So after several longish days pulling CNC apart …

so can add dust covers to X axis, including several rinse and repeat cycles to fix minor mistakes (dust cover too long, dust cover = rubbery = grabs and wraps around the drill 3 times!!!), causing large issues, almost have X axis covered pretty nicely…Y will get very simple if any as my patience is wearing very thin!

Well maybe tomorrow more cutting…