26

Re: X6-1500GT CNC router

Yeah, a 500w + laser may be beyond my means at this point in time.  The CNC router approach is however looking more and more attractive and realistic for me.  At the risk of being too off topic,  I ran across some plans for a KRMx01 by Michael Simpson that I'm considering.   Just thought Id mention it in case anyone has some experience or insight into this design.  Will start a new thread if I actually squeeze the trigger and anything comes of it.....

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Re: X6-1500GT CNC router

The following are overviews of some of the early experimental cuts I've undertaken using the router. I will detail the software I use at a later stage.

Test Cuts: 2D Image to 3D Surface

Meshcam is the software I use to generate toolpaths (just like Slic3r for 3D printing). Apart from taking 3D STLs, it can also take 2D images and generate a 3D surface by turning the light and dark regions into high and low areas. In Meshcam, all that is needed is to tell it the length/width of the resulting cut, the depth of cut and whether the dark or light parts form the highest points of the 3D surface.

After the height map has been generated, Meshcam can also apply a filter to smooth it out before cutting.

Cutting was configured so that the tool would go back and forth in parallel, horizontal passes 0.5mm apart, with a solid carbide round nose ball mill. Spindle speed 2400rpm, feedrate 1000 mm/min, plunge rate 500 mm/min. At the deepest point only 3mm is being removed, and this high quality cutter went through the melamine panel with ease.

http://imagizer.imageshack.us/v2/150x100q90/30/d3ax.jpg

http://imagizer.imageshack.us/v2/150x100q90/191/wwtr.jpg

I'll make a video of a small 3D surface being cut at a later date.

28

Re: X6-1500GT CNC router

Test Cuts: Aluminium Plate

One of the main reasons I wanted the CNC router was to experiment with cutting sheet/plate aluminium. I have a product I designed a couple of years ago that cost me $700 (via laser cutting), which I figure I could make for <$100 with the router.

The test material here is 2mm aluminium plate left over from another project. The design is a simple gear generated with the free involute gear plugin in SketchUp. A toolpath was then generated using Meshcam.

The first attempt approached the challenge in the same way as how I have been cutting 3mm acrylic sheet. This meant a full depth cut, really slow.

http://imagizer.imageshack.us/v2/150x100q90/19/jhmh.jpg

Unfortunately this yielded a terrible result, with the cutting bit rubbing on the aluminium so much that everything heated up and the aluminium melted around the cutter. A second pass with a spray bottle of water to cool and lubricate the bit was needed to free the part.

I spent the night reading up on milling alloys and learnt that spindle speed and feedrate should be matched so that nice waste chips are being produced by the cutter. The bit should be taking a neat scoop out of the work piece on every rotation. Too much rpm or too slow feedrate and everything just rubs and gets hot, too little rpm or too much feedrate and the bit tries to take too bigger piece and is likely to snap or at least chatter. Cutting multiple passes at partial depth is also the norm.

Experimentation continued but by controlling the machine manually. With spindle rpm at only 5000rpm, I jogged the cutting bit down into into the aluminium about 0.5mm and then manually moved it around at varying feedrates. The aim was to get a nice metal shaving cut at the fastest possible speed. This was very valuable and despite some broken cutters, a good combination was eventually found.

3mm cutters were a bit fragile and prone to breaking, with 6mm almost invincible. A good compromise was something like a 5/32 inch (~3.9mm) HSS 4 flute end mill. 5000rpm with 800mm/min feedrate and 0.25mm depth passes with the plunge rate at a very slow 75mm/min as this is where the machine struggles the most (when it goes vertically down like drilling for each new pass).

The chips coming off in the video are beautiful, which sounds funny but is the result of much trial and error. In this video I'm actually cutting 5mm plate aluminium with a 6mm end mill, again with 0.25mm depth passes. It shouldn't really matter what thickness is needed, just keep completing passes until the final depth is reached.

http://imagizer.imageshack.us/v2/150x100q90/6/zdka.jpg

Above is a finished piece in 2mm aluminium. I have given it a light sand to remove the burrs. I intend to purchase a buffing wheel. The left hand wheel on the one at work instantly removes imperfections such as these and the right hand wheel polishes to a fine shine.

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Re: X6-1500GT CNC router

Lawsy you would have saved a lot of time and prolonged the tool if you took my advice to give g wizard a try. The whole purpose is to generate the best feed rate and it will save you head aches like no tomorrow.  When I was 14 I had a cnc router and learned the hard way. This software would have save me time and end mills if I had it then. I would use a 2 to 3 flute end mill for aluminum sense you have very little torque and rigidity

Powder coated steel enclosure, 1/4" Surface grounded hardened aluminum plate, MK2A Heat bed, .200 Polished fused quartz plate, Machined quick change hot bed mount, E3D hot end, Ramps 1.4, DRV8825 stepper motor drivers

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Re: X6-1500GT CNC router

I looked into it but the 'subscription' model is something I will never give my money to. When I pay for something, I expect it to be mine. I have been using other free ones that do the same thing:

http://zero-divide.net/index.php?page=fswizard

Furthermore, generally my machine is not rigid enough to go above what I have it set to. The values output by the calculator above are pretty good but I have to limit the spindle rpm to 5000 and then the rest is realistic.

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Re: X6-1500GT CNC router

It's close but g wizard provides you with a little more data and gives you more options.

You can by the lifetime subscription on sale every now an then, again it's not a physical software program that you own
to an extent but he's a big name in the industry.

Next time your about to cut something give me your tooling and material type and max RPM and I'll plug it in to the full version so we can see the differences if you would like.

Takes me a minute so I don't mind doing it

Powder coated steel enclosure, 1/4" Surface grounded hardened aluminum plate, MK2A Heat bed, .200 Polished fused quartz plate, Machined quick change hot bed mount, E3D hot end, Ramps 1.4, DRV8825 stepper motor drivers

32 (edited by kwest 2014-01-09 21:48:18)

Re: X6-1500GT CNC router

lawsy wrote:

I looked into it but the 'subscription' model is something I will never give my money to. When I pay for something, I expect it to be mine. I have been using other free ones that do the same thing:



Furthermore, generally my machine is not rigid enough to go above what I have it set to. The values output by the calculator above are pretty good but I have to limit the spindle rpm to 5000 and then the rest is realistic.

All you need is G-Wizard Lite, so think of it as you're paying $69 for the software. Rigidity is your limiting factor so I'd guess you'd have .15hp when it comes to using G-Wizard.


A few tips for future projects if you're new to machining.

  • Use the correct cutter for the job/machine. For CNC routers this is very important, too many flutes and not enough feedrate will cause the cutter to rub. Rubbing will cause extra heat in the tool, where cutting puts the heat into the chip. There are some nice single flute endmills designed to cut aluminum.

  • Cut deeper with less stepover when doing clearing operations, you get the most life out of your tooling.

  • Clear the chips. Recutting chips is hard on tooling. A little air blast, vacuum, or even a long artist brush with do

  • Use HSM tooling paths if you can. This is so important on small machines, having smooth motion and even tool load will    make a huge difference in surface finish.

  • Use separate roughing and finishing operations. Surface finish only matters on the last few passes, save time a rough at a higher feed rate and then slow down for your finishing pass.

  • Try cut finishing passes at full depth, even if it means taking a small cut

  • Rigid setups are key to good surface finish and tool life

  • Avoid plunging an endmill into material, endmills are horrible drills. Use helix, ramp, smooth profile if your CAM software supports it. If not then use pre-drilled holes were possible.

This is my XZero machine with a 1hp Teknomotor spindle cutting 6061-T6 using HSM Works tool paths. This was one of my first cuts on aluminum on the new machine. I can't posted links as I'm new. youtube.com/watch?feature=endscreen&NR=1&v=7d5J46hroCI

Now I'm cutting 5mm deep and 1.25mm stepover at 3200mm/min for roughing operations. Finishing passes are full depth .5mm at 1400mm/min, minimum of 2 finishing passes with a repeat of the final pass.

33

Re: X6-1500GT CNC router

Have you had any problems running off USB?

SD2 - Glass Bed, Fans on PCB and Y motor, Custom enclosure
Slicer - Simplify3D

34

Re: X6-1500GT CNC router

when we cut aluminium with hole saws and any toothed saw, we spray kerosene on the cutter and it stops the aluminium galling... melting to the cutter make a really shiny cut too

35

Re: X6-1500GT CNC router

My my experience with the x4 and x6 mini cnc cutting aluminum kinda slow but with a 1/8 carbide single flute does amazing. You have to use 6061 or harder.. the 3003 AL is too soft and gummy so even slower speeds are needed. This is if you want to cut with no oil/water/air etc.

I sold the X6 because of the flex and inaccurate play.. its larger.. and chinese. The X4 is smaller and bit more tight and accurate though you only get 800w vs the 1500w spindle iv not noticed any issues with power. Chances are you dont need the larger work area the X6 would provide.

36

Re: X6-1500GT CNC router

I noticed the height limit is 60MM?

I really want a machine like this I just need a little more Z height, more like 12 inches or so.

Seems like it would be difficult to use the 4th axis with only 60mm of travel.

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Re: X6-1500GT CNC router

You can slide the spindle in the mount higher or lower to suit what you are cutting. For instance if you are working with a 60mm material, you slide the spindle higher to get above it.

Just did this for a colleague to celebrate the birth of her grandson. Carved into Merbau with no sanding afterwards at all. The finish is simply vegetable oil.

http://imagizer.imageshack.us/v2/xq90/560/7m84.jpg

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Re: X6-1500GT CNC router

So what is the maximum height then 100mm?

Very nice!

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Re: X6-1500GT CNC router

I'd have to measure but the maximum height is dictated by the base of the spindle mount and z axis  mounts. I'm guessing it would be at least 100mm.

40

Re: X6-1500GT CNC router

Ok. So overall would you say you are happy with this?

I am getting ready to pull the trigger on one.

41

Re: X6-1500GT CNC router

For sure. It's not as rigid as a big dollar machine but for the money it's great. Also, yesterday I used the smaller one I set up for work and it seemed like a toy in comparison, everything was smaller and not as well made.

42

Re: X6-1500GT CNC router

Well I got me a 3040 off ebay. Already did a PCB etch on it and it was perfect.

SD2 - Glass Bed, Fans on PCB and Y motor, Custom enclosure
Slicer - Simplify3D

43

Re: X6-1500GT CNC router

Trying the 4th axis today. I will be trying Deskproto software as it has continuous 4th axis milling:

http://www.deskproto.com/

Already I have discovered that the steps per mm for the rotary axis are incorrect at 13.33. After searching, I found the answer here:

http://www.cnczone.com/forums/chinese_m … ost1385558

agurkmedia wrote:

16.66944476

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Re: X6-1500GT CNC router

First 4th axis job went well. Limiting factor was the large size of the ball nose cutter I was using. The Venus bust shown here was only 40mm tall so a 3/16" / 4.8mm ballnose cutter was never going to get the detail required. Everything else was a success, however.

Software used was Deskproto trial v6.

http://www.deskproto.com/

After using it just once I am a big fan of the software and will purchase a hobby license. I highly recommend both this and Meshcam. Meshcam is simpler to use but can't do continuous 4-axis milling.

Stock was cheap and nasty 35mm diameter pine dowel I had lying around.

Model was Venus de Milo statue from DeskProto site. They have a series of videos on machining this model:

http://www.deskproto.com/support/videos-venus.htm

I setup the basic parameters of my machine and software, rotated and scaled the model and set up the rest of the little things as shown in their video. First pass was continuous A rotation with X steps:

http://imagizer.imageshack.us/v2/xq90/812/ruv9.jpg

I also made a second file with X cutting and A axis steps:

http://imagizer.imageshack.us/v2/xq90/197/n7nh.jpg

As discussed previously in the thread, the spindle was moved up in its mount to create safe space underneath for clearing the 4th axis hardware. Table to 4th axis centre distance is just under 60mm, so the largest diameter stock you could safely machine like would be approximately 110mm.

http://imagizer.imageshack.us/v2/xq90/856/nv98.jpg

Final result was pretty good considering the mismatched cutter size. The second cutting pass wasn't really needed and could be omitted to save time. I am about to order some 2mm diameter ballnose cutters to do things like this with sufficient detail.

http://imagizer.imageshack.us/v2/xq90/812/ddyh.jpg

Summary video:

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Re: X6-1500GT CNC router

Your evil, you have helped convince me I need a Tormach 1100 PCNC

http://www.tormach.com/product_pcnc_main.html

You got me started on a dangerous path.

46

Re: X6-1500GT CNC router

Welcome to the club. I'm having a ball with mine. Yours looks like a serious bit of gear!

Part way through running the Venus de Milo job again but with a larger bit of wood to get more detail. Got too late with the noise last night.

47

Re: X6-1500GT CNC router

How is the workflow?

If i understand correctly its 3D modelings -> CAM software -> Mach 3?

Yes, the Tormach is a nice personal CNC.

I plan on doing lots of metal work and threading and stuff like that. The work area is larger as well.

48

Re: X6-1500GT CNC router

Spot on with work flow.

I assume you found the aluminium milling demo on their website. Super impressive!

The only thing is it looks like there were many tool changes, which are a pain in the arse in my opinion. I have a z height probe I haven't played with, so hopefully there is an efficient way for you to change cutters and set the z height.

49

Re: X6-1500GT CNC router

They all have thier own settings. Once you get them programmed in you just change.

Without the power draw bar.
http://www.youtube.com/watch?v=eQmNlIVki2U

Skip to the end for power draw bar.
http://www.youtube.com/watch?v=-kxw9d6kI7A
20 second tool changes..

50

Re: X6-1500GT CNC router

I might have to settle for a X6-1500gt for now.

Have you tried using blender cam?

I will be in the market for a free cam software.