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Posted by BulletMaster | Nov 21, 2012 @ 06:40 AM | 5,219 Views
It's been a long time since my last post. Things have improved considerably on the CNC. I finally got around to making a new table for it.. Used 19mm MDF for the base, then screwed 5mm MDF to that. Used a large router bit and faced the cut area off... Then used WestSystems epoxy to coat the whole shebang. Finally, drilled a grid of holes and fitted threaded inserts for attaching clamps to the deck. Much better run-out wise now. But I still need to make that pressure foot for engraving the plastic traffolyte material as it buckles as you engrave it giving uneven depth of characters.

Some video of CF cutting..
MotorMountCut (0 min 16 sec)

Posted by BulletMaster | Aug 28, 2012 @ 10:21 AM | 5,614 Views
Due to the base table being all out of wack.. it has been impossible to do engraving reliably well. I tried replacing the base with some 12mm plate steel, but that was inaccurate. So I finally used some 18mm MDF as a base plate. Then added some 5mm MDF the cut area size, screwed to the base.. then faced off that piece. I then coated it in epoxy and re-faced. All that's left to do now is drill a pattern for threaded inserts to be put in for hold-down clamps... should be MUCH better..
Posted by BulletMaster | Jun 08, 2011 @ 07:08 PM | 8,474 Views
I guess now I really need to start doing some useful projects. Number 1 might be a foot that I attach to the spindle to allow both vacuum suction and compressed air blow in to clear & cool the cutting bit.

I also want to cutout bits to make a flightline box for my pylon racing. Best get drawing on that one.
Posted by BulletMaster | Jun 08, 2011 @ 06:57 PM | 8,746 Views
Yipee! Finally spent some time yesterday with the beast and wanted to achieve a true 3D cutout from design to finished product. Well, using Autodesk 123d Beta for the design software, I created a simple tube with rounded ends. I then saved as an stl file (3D export format) and imorted that into a trial version of CAMBAM (will definitely be buying this software). From there I positioned the model so I was only cutting about half of the cylinder & then created the toolpaths. Copied the resulting GCode to the Router... (inserted a 3.2mm Ball nose end mill) and set her off....

I will say there were some issues... during the process the z-axis must have slipped , which put it out about 1.5mm. I tightened the drive connector and continued one (no more slippages after that). Also it took a LONG time. Have to work on that bit I think...

The machine is also nice and quiet during operation.. I was quite OK to leave it cutting late at night without fear of disturbing the neighbours.

CNC - 3D Testing (0 min 23 sec)

Pics below of the final object..
Posted by BulletMaster | May 09, 2011 @ 08:23 AM | 7,693 Views
My order of router bits from the US arrived today. But I still haven't seen the new collets (different sizes) & router bits that I ordered via ebay (HK). I will try and have a play tomorrow arvo and see if I can cutout some T6 Alloy turnfins for boating applications.

Also played with the FREE google sketchup 8 software (3D CAD software)... pretty groovy, plus with a plugin installed you can export 3D .stl files that the FREEMILL software can work toolpaths out on. So, might be time to have a go at some 3D milling soon too.

Update - I did cut out a turn fin from some T6. Needed to use a proper endmill with cutting lubricant & really shallow cuts. But the finished product turned out quite well.
Posted by BulletMaster | Apr 26, 2011 @ 08:03 AM | 7,966 Views
Sooo... Finally I have a few days off, so can spend a bit more time with the machine.. Spent today messing with various CAD/CAM programs to sort out how to do this stuff properly. Finally settled on combinations of CAMBAM (will probably purchase full copy of this one), EmachineShop CAD & DraftSight for CAD.

I was going to cut a spanner for undoing the collet assembly but had an oops moment while playing with the machine & snapped the sole end mill I had.

So waiting now for some tools that have been ordered... plus still waiting on the collet set I ordered the other week.

So far spent around $150 on tools/bits and another $150 on software.
Posted by BulletMaster | Apr 21, 2011 @ 12:20 AM | 7,906 Views
Woohoo... I nailed it today! Finally sorted the spindle issue and made my first CNC cuts today.. I have some quicktime video, but it's a large file (and quite boring). I still haven't hooked up the watercooling, but now I can start to think about locating the unit properly and setting it up in it's workspace...

Oh, by the way, to solve the spindle issue involved running an earth cable from the spindle mount, to the VF Drive, then to the Control box Power supply (240AC/24DC), to the Control box incoming 240V Earth. Seems to run very stable now.

Video here:

DSCN0895.MOV (1 min 13 sec)

Posted by BulletMaster | Apr 16, 2011 @ 10:26 AM | 8,164 Views
It's true! I have officially gone potty... this machine is driving me nuts. I really need to sort this spindle issue, but it looks like I have to go on a serious grounding issue to tie all the points together at the same potential... Wish it had been done right at the beginning. I pulled the spindle off the machine and measured 60V AC (spindle to bed) with the VF Drive powered and 140V AC at full RPM. Not good. Earth continuity seems to be good on the machine itself. So now I need to get the control box, the PC, the spindle and the VFD at the same earth potential (tied into the 240V supply earth).
Posted by BulletMaster | Apr 15, 2011 @ 09:42 PM | 8,256 Views
Hi guys....

Well, I decided I couldn't wait until the new spindle collets arrived, so I machined up a split spacer to make the 3.2mm bits fit the 6mm spindle. All worked out fine, so now I had a machine that I could cut with. Excellent! (or so I thought). I setup the job (a simple test piece). and then fired up the spindle. Opps! Mach 3 didn't like that, an external EStop request was registered. I did a bit of research and the VF drives can throw spurious requests due to generating noise in the system. So then I made sure the VF drive was grounded (supply and to the spindle). Same result. The Spindle motor cable is not a sheilded type, so I removed it from the cable snake and gave it clearance from the other cables. Still the same result.

Not sure which way to go now... Time for an email to the supplier I think.
Posted by BulletMaster | Apr 13, 2011 @ 11:45 PM | 8,192 Views
Hmm... spent the last couple of days getting used to the setup and doing dry air-runs. Decided today was the day, I was going to do some real cuts. Created a shape on the freeware emachines software, exported the dxf file to Mach3 and converted it to GCode. Setup the router & limits, all was looking good. Then I went to fit a cutter tool...! *###... the tools supplied are 3mm shank and the ER11 collet supplied with the spindle is a 6mm one! So... basically no chance.

I have ordered a set of ER11 collets, that will let me use up to 7mm tools and down to 0.05mm. So now I have to wait (or get some 6mm cutters from somewhere).

Might be time to get the full licence for Mach3 software...
Posted by BulletMaster | Apr 11, 2011 @ 11:31 PM | 8,607 Views
Just powered it all up (excepting the pump & VF drive). Setup as per the downloadable manual (check ebay for the right one). Changed some port settings & direction settings... and away she went. There were some test GCode files in the Mach3 software, so I ran through a few of them with the spindle set high. Very happy... Runs like a dream!

Now to do some actual cutting - but first to sleep!

I have video of the first test runs.. will upload later.
Posted by BulletMaster | Apr 11, 2011 @ 08:33 PM | 8,701 Views
I pulled the lid off the stepper control system to check that all was good inside. Looks like quite a reasonable unit with potential to be a 4 axis controller with PWM output for spindle speed control.

All motor functions are now connected. I haven't plumbed the spindle cooling or setup the VF drive yet, as I won't be doing any cutting for a little while. But Mach3 software is installed (Demo mode) and connected to PC. Just have to setup some initial configurations and then give it a go...
Posted by BulletMaster | Apr 11, 2011 @ 12:52 AM | 8,695 Views
So... have the Gantry mounted, had to loosen some bolts to remove a tweak that must have been caused by transit knock. All good now. Motors all mounted. Water cooling pipe & Spindle cable run.

Lots more to do... starting to think that maybe the dining room table was not the best place to set it up at.
Posted by BulletMaster | Apr 10, 2011 @ 07:37 PM | 8,506 Views
I just wish the packing tape that was used would come away cleanly from the items, and not leave the sticky residue. Have a bit of cleaning to do before assembly.
Posted by BulletMaster | Apr 10, 2011 @ 07:17 PM | 9,425 Views
Well.... I finally did it after deliberating for ages. I went ahead and ordered one of the ebay units. They looked great for the price (around $2000 AUD landed). And today was the big day that it arrived . Ordered it on the 29th March, in my hands on the 11th April. Not bad I would say considering it shipped from China.

I will post some pics below of the unassembled unit exactly as I have unpacked it from the adequate packaging. The only damage sustained so far I think is a couple of dings on the corners of the Gantry and a slightly bent cable support bracket on the base (also noticed the table has dings on all 4 corners). But we shall see how it all goes together and time will tell on this.