So after several months....

[dfurlano]

I finally finished modifying a Grizzly mini mill to be a 4 axis CNC.

My first project was to try and take a 2D image and wrap it around a cylinder. This is going to be a ten year anniversary ring pen with Irish accents.

Here is the test part. I used a scrap piece of wood and filled the engraving with black CA. The finished part will be IBO with silver leaf filling the engraving. Things were going rather well till I lost the Z zero and the tool crashed into the barrel on the bottom text. But got enough of it done to prove the design. Need to change the font.

Sides

 

[wood-of-1kind]

Looks like you have a 'special' project on the go. Keep us posted with new developments, I for one am very interested here.

Regards,
-Peter-

 

[angboy]

Originally posted by dfurlano
<br />I finally finished modifying a Grizzly mini mill to be a 4 axis CNC.

Huh?? You did what??[?][?] I have no idea what the heck you're talking about, but the end result looks nice!

 

[Dario]

Congratulations!!!

Very impressive!

 

[JimGo]

WOW!

 

[alamocdc]

KEWL!

 

[vick]

Great stuff I am truly jealous. Of course I would not know how to work it if I had it but that is not the point.

 

[Yarael]

kewl Nice looking old Dell portable there[] looks good hope the cnc works out for you

 

[DCWoodworks]

Originally posted by angboy
<br />

Originally posted by dfurlano
<br />I finally finished modifying a Grizzly mini mill to be a 4 axis CNC.

Huh?? You did what??[?][?] I have no idea what the heck you're talking about, but the end result looks nice!

Angboy: CNC stands for computerized numerical control. Basically alot of big words that stand for a computer controlled machine. The computer controls the mill through numbers in a program, usually called G-code or conversational programming, depending on the type of control.

 

[tcastel]

Congrats Dan...Just curious who's servos and control software are you using. I've been designing an building CNC's for almost 30 years if you have some glitches that drive ya nut's (which isn't uncommon...lol) I'd be happy to give ya any help I can

 

[justdawn]

Aren't CNC machines fun? My better half made one from scratch, but its not 4 axes.
I'd love to hear how you did yours, I'm intersted in making the 4 axes for my pens.

Looks like you have done an excellent job.

You can see a few of the things that have been done on our CNC machine at http://www.igcomputers.net/gallery/woodprojects

I do the pre-work (cleaning up images etc, and he runs the machine.

 

[Mudder]

Dang Dan;

That's a project and a half!

How many hours do you have invested in the design and implementation?
That looks like something I would like to do but don't know where to start. Did you find any help online? I have researched a little but wondered if I could "actually " do it.

I'm really impressed.

 

[dfurlano]

Well I found information on my own searching the web but there are two experts on the pen forums (that I know of) that can easily help you. Dan Symonds who is mostly on the yahoo forums and Tony Castellani (two posts up) that can give you assistance. They both offered help and I would assume you will get more out of your money then I did if you work with them. I Wish I knew before I started but I'll bug them about other issues.

All in all it isn't that difficult but it can be trying because things tend not to work out exactly as planned. The biggest headache was the Z axis and then the A axis. I would have done the Z differently.

By far the biggest learning curve is the CAM software. You will end up using multiple programs to get what you want done.

For the machine controller I use Mach3 from www.artofcnc.ca which only cost $159 and I would highly recommend this package. Nice thing is you can download it for free and actually use the software. It has a 1000 line limitation until you buy a license. It has a bunch of canned routines for drilling and milling and the new version have a 2D milling package called Lazycam. It can also do digitizing.

I used Pac sci steppers on the X and Y with 5/8" rolled screws and over sized ball nuts. I get less then .0005 backlash. On the Z I also used a 5/8" rolled screw and ball nut. On the Z and A axis I used generic 270oz steppers. To mod the rotary table I had to disassemble the table and put thrust bearings on the shaft. It has a tendency to bind at high speeds. I need to see if I can fix that problem but with the thrust washers I get almost zero backlash. For the driver it was a prebuilt 4 axis unit based on a Xylotex 2.5 amp per phase (max) bi-polar chopper drivers.

Dan.

Originally posted by Mudder
<br />Dang Dan;

That's a project and a half!

How many hours do you have invested in the design and implementation?
That looks like something I would like to do but don't know where to start. Did you find any help online? I have researched a little but wondered if I could "actually " do it.

I'm really impressed.

 

[Paul in OKC]

I'm jealous! I can use the cnc at work, but it would be like making a toothpick for size comparison!

 

[btboone]

Great job Dan. It looks like your stepper motors are plenty beefy for pens. That's the problem with the small machines is they don't have feedback, so if they get tweaked off the count where they think they are, the part suffers. I'm certainly glad to see other people experimenting with this stuff. I think it's one very promising avenue to making higher end pens.

I got curious after the last thread mentioning CNC to try and create my own tool for fine engraving like the stuff on the Tighe pen. I sharpened a broken 1/8" carbide bit to a point and ground off half of it. It worked like a charm. I carved titanium with around a .008" cut. It would work well for fine graphics like yours or stuff like signatures or other line drawings. I've also been thinking up my next 4th axis design. Just need time to try it out.

 

[dfurlano]

The pen about was .015" deep and that worked great. I use an engraving tool that Dan Symond's told me about.

I am trying to find an affordable thread cutting tool. The cheapest one I found is at Harvey tool for 60 dollars:

http://www.harveytool.com/products/product_detail.php?product_id=71000-C3&product_family=Thread+Milling+Cutters&category_id=1

I may break down at some point and get the MicroKinetics cnc lathe:

http://www.microkinetics.com/btlathe.htm

but I am going to hold off for now.

Oh yea, on thing about stepper motors you do not need limit switches

Dan.

 

[btboone]

Dan, MicroKinetics is where I got my tabletop CNC mill, and they are right near me. I used to actually work with the sales lady MaryAnn there. If you are interested in going there, please make it a point to stop by here and we can talk pens and CNC.

 

[dfurlano]

Yes, you were the person that pointed this equipment out.

Ok, you made me an offer I cannot refuse. I will try and schedule something in the Atlanta area and let you know. I talked to Maryann and asked for a discount on a class if I bought the lathe but she graciously declined. I would really like to see your setup and discuss techniques.

Thanks for the offer.

 

[btboone]

Dan, the equipment is very easy to program. I can show you all that. The software that comes with the machine is all you need as long as you can pick some dimensions off a CAD drawing. I like to dial in a design in CAD and use that to cut a pen. It's pretty cool to make a part from several components that actually fit together and work the first time out. It takes a bit of learning curve to get there, but it's darn cool once you do. []

 

[Johnathan]

My goodness! Now that's some serious hours into that project. Great job, way over my head.

 

[dfurlano]

Here are some short clips of a test using the rotary axis (~10 meg files):

I'll report later.

 

[btboone]

Dan, I'm not able to see the new mpgs on my computer. Do you have a jpg of the signature?

 

[dfurlano]

I'll post it tonight when I get home. The mpg files are weird because I can view them at home but on my work computer I am missing a codec. It may be mpg4.

 

[Paul in OKC]

Ok I couldn't resist showing MY four axis set up[] Actually it is the one at work. (Think I need a smaller bit!)
Comes complete with coolant to put the fire out on the pen if I get too carried away.

<br />

<br />)

 

[btboone]

Check out that Haas action. Paul, you'd be proud. I was actually working on a wood pen last night and was using my 4th axis machining center. It's long way from done, but i was nice to work on a pen for a change.

 

[Paul in OKC]

Originally posted by btboone
<br />Check out that Haas action. Paul, you'd be proud. I was actually working on a wood pen last night and was using my 4th axis machining center. It's long way from done, but i was nice to work on a pen for a change.

Yeah, one of these days I will get to do pens again. Haven't turned but about 6 in the last two years. Been at least 4 or 5 months since the last one[]. This machine is fun to play with doing real jobs in. I do get to use it to stencil my name on my vises though!

 

[dfurlano]

Things I learned about signatures:

1) Garbage in garbage out. I scribbled my name and thats what I got. JPG of the sig file: (I blanked out my last name).

2) Maple does not reproduce fine detail very well. I did not want to use a piece of metal to trial the file but it would help in getting the detail better.

3) Sizing, depth and material are important I tried several depths but due to the poor reproducibility in maple if you do not go deep enough it does not look clear, too deep and it is hard to read.

Too deep:

Not deep enough:

Also here is the video I reformatted it so let me know if it does not play (11 meg windows media file):

http://www.dfurlano.com/sig1.wmv

Later I will put up the other video files of the circles and screen.

 

[woodman928]

I bought some very small drill bits from HF they came in as a set and had 1/8" shafts and a little plastic stop on them. They were like .047 and smaller. I used them in my Andi CNC to cut the holes flat on one side of the tracker bar on the street organs I build. You have to use high spindle speed and VERY slow feed rates but they did work, you just have give it time.
The point I am trying to make is try a different bit. (Smaller)
Jay

 

[Ron in Drums PA]

Well Done Dan!! Super Impressive!!

BTW - Do you have a tutorial?[]