Cool Panel Cover Logo #107 - Dakovo, Croatia

[Fox]

The edges indicate that feed and speed is indeed not right, swarf sticking to work and tool (probably). You should be able to get a 'clean' edge finish off the table with a good chip load. For sure use some sort of readily available lubrication, wd40, lamp-oil (paraffin) works, etc etc. Watch some videos on youtube to get an idea....For try outs just brush the lubricant on, later maybe build a nice mister like Ross did. Use 2 flute or single flute.

Ps. i don't know your background; What a lot of 'newcomers' don't know is that you have different qualities/alloys of aluminum, and they are all called aluminum with different strengths, but more importantly.... that also cut very different, some are stronger and very difficult to cut on a router table with high RPM spindles.

[marcobc]

Almost every day I am cutting aluminium 2mm thickness. In first I experimented with a lot of kind of bits, and the best is one flute, shown on picture below


This bit provides best chip, and good cutting edge, without cooling.
It is hard to find bit with this shape. I bought it from local dealer, ant bought all he had.
Recently I found site of German manufacturer, that have this type of bits. Try to find if they are available in your country.

I forget, rpm 9000, feed rate 1.2 m/min, plunge rate 1.2 m/min spiral
I'll record when i cut alu next time.

[marcobc]

site of German manufacturer
http://www.werkzeug-navigator.com/DE/HKnavigator.aspx
Item no. 15007060

[smreish]

If in USA - this is where I purchase my bits for everything. They have the single flute too.

http://www.hartlauer-bits.com/HartlauerBitsList.pdf

[Gerald D]

Originally Posted by Fox

. . . . . you have different qualities/alloys of aluminum, and they are all called aluminum with different strengths, but more importantly.... that also cut very different . . . . . . .

Agree 100%

Most people think that all aluminums are similar. They are not. There are huge differences.

[marcobc]

I tried 2 kinds of aluminium. first Al99.5, which is softer, and it is harder to cut him (must be lower rpm and feed rate). Second one is better ALMg3 (approximately rpm 9000, feed rate 1.2 m/min, plunge rate 1.2 m/min spiral)

[marko cro]

Well, to say I am amazed for this kind of help, would be an understatement.
Thanks a lot for this.
The alulminium I was cutting was lying around the workshop before the MM came alive, so there is no way for me to figure out what type of aluminium type is it.
If you can record that video of cutting aluminium, that would be a blast.
I have some different types of aluminium, and will test it tommorow.
20 mm per sec is great speed for aluminium. Hope I can come near that soon.

[marcobc]

I forgot, pass depth 0,5 mm.

[Gerald D]

Aluminium is not only available in different grades, but each grade is available in different "tempers", due to heat treatment or "work-hardening". The tempers also have an influence on machining.

[Gerald D]

Any volunteers to summarise this article for us?

[pblackburn]

McMaster has a quick reference here.

http://www.mcmaster.com/#catalog/119/3626/

Where I work we primarily use only 6061

[marko cro]

After some reading and some trial and error i got this
12000 RPMs, feed rate 10 sec/s stepdown 1 mm. Little or no lubricant.
Trying to get some tutorials on high speed maching in mastercam.
Better?

[danilom]

I think High Speed Machining is tough even on some VMC's or machining centers and would be too much stress and tool breakage on a Mechmate.
For that kind of machining you need lots of rigidity and power.

[marcobc]

I have uploaded video.
http://youtu.be/nbytoYSw76k
http://youtu.be/T8cZtZ20X-Q

Here are some pic of work:






When the bit is not sharp, cutting edge looks like this:
[/URL]

[marko cro]

Thanks Marco for very cool videos.
I wonder if anybody has a dfx of spindle mount to share.
I cant connect to my computer where I have it, and could use spare time to cut it.
I couldnt find any plans on the forum.
Here is what I have been doing for these last few weeks.

[darren salyer]

Nice Work....

[pblackburn]

Everyone mounts their spindle a little differently. Thin back plate, thick back plate, steel design, aluminum, etc... If it is a 2.2kW then it is I believe an 80mm. Most use a clamp mount. Mine used the standard 2 dowel pins but 2 holding bolts and is all 25.4mm Aluminum. Five piece, all bolt together.

You have been busy I see. Good Work!

[marko cro]

Thanks guys.

I have been working, and soon I hope to get more and more work, but..
I have a problem.
2 times I have been cutting aluminium, and machine went full stop.
The problem is like this.
In the middle of cutting aluminium, machine suddenly stops at place, and wont move.
I am looking at mach 3 and I can see that coordinates are moving.
When I press escape, Mach stops, but i need to press 2 times reset button to gain control over machine.
It happened 2 times, and both times on aluminium. Not sure what is happening, suspecting for the computer to be faulty. Or the parallel cable is faulty.
I have been cutting longer times and had no problems like that, some other yes, but not like that.
Anybody had similar problems?
Can it be something with current in the machine?

Marko

[smreish]

Does the same exact cut file stop when your cutting a non-conductive material? Like wood or MDF?

[marko cro]

Nope,

Only on aluminium.
I tried wood and all other stuff, and only stopped on aluminium.
But it does not stop every time.

[smreish]

To be honest, I have had something similar happen - but I don't know what it really the answer.

1st question - does mach show any indication that it has stopped? Or is constantly running the code queue?
2nd question - does the drive or drives disable? Or go into thermal protect?
3rd question - do you have proximity limits on your z axis? ( I have had to isolate the 12mm body from the machine metal mounting because the ground issue has caused my machine to either stop, or caused the z axis to "tick up and down" without direction from Mach IF spindle was running.
4th question - does your spindle have ceramic or steel bearings? And can it ground itself thru the tool bit?

It sounds like an EMF / Grounding issue. Have you tried grounding the alum part your cutting?

[slobato]

Nice work Marko. A question, What´s tool do you use to draw these project?

[marko cro]

Thanks Sean,

1. Mach keeps on rolling with code like nothing has stopped.
2. Motors are cool and even below 37 C
3. I dont have proximity sensors yet.
4. Dont know about bearings, but i think its not ceramic.

I have felt some static charge when I was touching the control box, but I ignored that and that never happened again.
Can it be that my spindle is doing some static and stoppping the motors?
Or is it that my drivers and control board have connection with metal?

Thanks Leonardno,

I mostly use artcam, solidworks and aspire 4.

[lonestaral]

I had an intermittent fault with the machine stopping.

Check your parallel port connections.

Also take the cover off the computer and vacuum inside especially the printer output.

I also put in a new earth on the computer and machine.
It has worked very well since.

Hope it works for you.

[marko cro]

Thanks Al,

Was just doing some wood cutting, and msachine stopped again.
Well that was revealing, and also anoying, so i tried to move it, and after pressing, it came finaly back to life, withoot me touching anything else.
So I set it to move, and kick it with my leg the control box, and it stopped again.
That is good thing, coz i know now that my cable if messed up, or something in control box.
Will deal with it tommorow.
Keep you posted.
Some aluminium cuts pics:

[marko cro]

Hello again. Im back with some news.
I discovered where was my problem.
I found my 5 V cable to my control board to be untrustworthy. So I tested it, and when i started to move it, the machine stopped.
Correct me if I am wrong, but if i physically stop my stepp motors, will the mach keep rolling the code? It happened 2 or 3 times when machine stuck in the melted aluminium, and lose almost no step, but was moving for few seconds.
Anyway. I redone the wiring, and machine worked in 2 times for 4 hours straight.
This where my new problem started.
I was cutting some reindeers from plywood and I set my artcam cut speed 100 mm/s.
As I loaded in mach, the machine did not go as fast as that. It moved only on straight lines with that speed. As mostly are curves, the job what was ment to do in 45 (artcam approximation) mins, stretched in 4 long hours.
Can you help me with that.
Not sure is the Mach 3 or artcam problem.
some pictures:

[lonestaral]

Marko.

100mm/s is 6000mm/min F6000.

Check your nc program and see what the feed value is, it should read F6000.

When the machine is cutting look at the Mach screen feed value.
It will show the commanded feed and the actual feed.

Yes the programm will still run if the motors are jammed or removed.

Nice deer and workshop stove.

[marko cro]

HI Al,

Machine says its F6000 but it moves around 5 mm per sec at some areas, mostly around 20 mm/sec and only on straight lines it get to full speed at 100 mm per sec.
Thanks for the info about the program and parallel cable.
Was thinking is it CV problem, or the computer muscle problem, but now I cant tell.
The job should be done in 45 mins flat, and it took almost 4 hours.

Stove is a work of art, the only thing keeping it together is the sheet metal around the edges, coz the inner plating fell off.

[KenC]

Marko,
Yes, the machine will slow down when cornering or changing directions drastically.

Now its obvious that its software setting or tuning error with your units. It can be anywhere, might be u forgot to put in the drive ratio in Mach3 set up, even be in your G-code... Give it a round of check & you might just find it hidden in plain sight.

[Robert M]

Hi marco….

Sorry to read your trouble…and dble sorry, I’m not confident enough to assist you !!
BUT…may I ask where did you get this nice dear drawing ?
I’d like to produce some for this time of the yr !
Beat of luck with your….troubleshooting !
Robert