"One Perfect Part at a Time"

CNC

Ramblin’

I have been making more lithophanes on the Taig. I don’t plan to show them all off here. Some day when I have enough  “good” ones I may decide to do a gallery here in Ramblin’ Dan.

I just ordered a backlighting kit from http://www.vibelights.com/info.html. Once I have it tested out I will show the results here. I may be buying a lot of these things.

The 5.5″ x 12″ work area on the Taig is fine for what I am doing now. However, the urge for a larger working area is always lingering. All my designs for a larger HB2 keep ending up looking like a certain commercial product. At least the designs with the components I can afford to use. Don’t be surprised (I won’t be) if HB2 ends up being a hybrid of commercial and home brew. There is little if any cost advantage to total component scrounging. As I have written in Funding HB2 there is retained value to tie in with a recognizable brand name product.

Next anticipated big event for Gloria and me (and Steve and Danielle and Aunt Shelley) in this little corner of N. Texas is the arrival of Tessa our first grandbaby sometime this month. Pictures will follow and of course Gpa’s plans for making “things” for her.  😉

Lithophane Making

Here is my latest creation. The carving is called a Lithophane. In the first picture you can see that it is a reverse relief carving. The darkest details are raised in the design The material is 1/4 inch thick Corian produced by DuPont. Its the stuff from which counter tops and wall covering is made. As it turns out, it is very easy to engrave.

The second picture is the same carving with back-light. As you can see, when illuminated from behind, it shows a very high detail gray scale photograph. You can even see the reflection in my glasses! The detail is outstanding.

In this example the photo area is about 4 x 5.75. Just the right size for the CnC Taig Micro-Mill. I don’t have a step-by-step example in my hobby web site yet, but I will soon. Probably this week end. I’ll post a link here.

What is hard to believe is all I used was two ball end mills to machine this picture. The first was a 1/8 inch mill for roughing out, followed by a 1/16 inch mill for the finish pass. That was almost 1000 lines. Total machining time was about 2.5 hours.

Update 4/20/08:

As promised, The Hobbyist Machine Shop has the lithophane making process in the web site. From the menu bar select “Projects” then select “Lithophane” from the drop down. Enjoy! ~ Dan’l

Small But Mighty

If you read the special Article I wrote called Funding HB2 you know I am struggling with the cost of building a large first class CNC router, especially the long term consequences of a large investment. Like many hobbyist, I become very zealous in studying all the details before I leap. Actually that is a worthy trait for the hobbyist that has if nothing else, a lot of time.

What I decided is HB2 is not a machine for business. I discuss that option in the other article. HB1 is definitely too small for the work I want to attempt such as 3D Lithophanes. So is the Taig, but the Taig does provide a 5.5″x12″ working area. I can dabble there. My vision for HB2 has focused in on a working area between 18″x18″ and 24″x24″. Standard quarter and half sheet engraving material can be purchased in 12″x24″ and 24″x24″ sizes. That makes 18″x24″ sound real good as a target size.

That smaller footprint can help provide a very stable platform because of the shorter spans at a reasonable cost for materials. Also that sizes HB2 components so they can be machined on my existing machine shop tools.

The shorter spans reduce the need for high speed rapids and put the controls back into the realm of stepper motors. The best part is I think for me, that it can be built out-of-pocket with no long term finance or pressure to get return on investment. Hmm… a hobby perhaps?

HB2 Ramblin’ Update

HB1 and TaigI have been spending some more time with my HB1 (Home Brew) engraving machine. I have been taking careful measurements of the movement of all the axis. In an earlier post I reported that there was a problem in the Z axis “dead-band”. As I have observed and measured yesterday, the backlash in the other two axis although not horrible are nothing to brag about either. This drives me to thinking about why I built the machine in the first place.

I was influenced by John Kleinbauer’s web site on building low cost CNC machines. I ordered and built his controller and bought a set of drawings. I was influenced by his concepts but not so much as to duplicate his designs. John is just a bit of a weird duck but he is sincere. Appearing public on the web is quite a challenge in time management. I believe the HB1 is every bit as accurate as John’s designs. I believe John has provided a path for a lot of folks to do more than as he calls it “spin motors”. His web site is a good place to check out low cost CNC.

That said, Having HB1 operational within a few hundred dollars budget is a great introduction to machine design and construction. It is a good operating machine but can not be used where 0.001″ accuracy is required. I won’t be carving jewelry designs, but that was never the intention. Simple wood carvings come out well.

The key to the new design for the HB2 is intention. Just what do I want the machine to be able to do for me? The wrong answer is “everything.” I have spent a lot of time deciding on “purpose”. I have invested in Vectric software as… Continue reading

More Fun With CNC

Steve and DanielleAnother carving done with a V bit on the CNC machine. It looks like the very old newspaper pictures that were screened before being printed. It is actually a very similar process. The Vectric software scans the picture for light and dark areas and that in turn sets the depth of the carving. Everything is adjustable by the user (me) so it takes some work to make it look just right.

That is only the computer part. The board is a piece of red oak and that needs some prep before carving. I sanded and applied two coats of shellac and sanded again. The board looks horrible after carving, so it takes more sanding and paint filling to get what you see here. Then a clear finish coat over everything.

The point is that I didn’t just push “GO” and out popped this print. There is a lot of work involved. But it is also a lot of fun to have a unique finished product at the end.

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