CNC
“Proofs” of Concept
I was doing some product research today. This is something I made in about five to six hours. I had been thinking of how I was going to make these all week. I just needed a good Saturday to give it a shot.
As the title indicates this is a proof of concept not a real project. I didn’t want to slow myself down doing all the pictures of the process. The process is still experimental so full disclosure can wait until a better time. I have my camera at the ready.
Long time readers know I have experimented with pewter casting before. Here is the LINK.
The “thumbs up” graphic is a 3-D rendering received free with the Vectric Aspire software. I used it to create the medallion. The finished result is seen in the first picture above. The picture was created within the software. I combined the thumbs up with some freelance drawing to form the disk. Actually in my opinion the disk is much thicker than it should be.
The edges of the disk did not come out well in the tool pathing. I need to find a better way to create the disk in the software. As this was a trial, I didn’t want to spend all day on the drawing so I accepted some imperfection in the edge rendering and moved on.
Next I had Aspire produce a roughing toolpath for a 1/8 inch ball nose mill bit. Then I had Aspire produce a spiral finish pass with a 5/32 inch ball nose. The disk is 1-1/2 inches in diameter. The aluminum (both pieces) is 1/4 x 3 x3 inches. The back plate is not machined in this test trial.
The machining was done on the CNC Taig mill. A… Continue reading
BobCAD-CAM First Test
I went through the full set of the supplied BobCAD-CAM V24 drawing tutorials and even though I am not a novice at this 2D and 3D CAD drawing stuff, I feel it is worth the time spent. The temptation is to cut corners and just dive right in. With any software this comprehensive it is best to follow the rules at first. There are many ways to skin a (Bob) cat they say, but it is best to make the first try with someone leading the way.
I am comfortable with the drawing (CAD) part in BobCAD-CAM. Yes, past experience helps a lot and any kind of previous CAD experience will be an asset. I am very pleased how complete this tool is for drawing.
The total user interface customization that is available is as awesome as it is daunting. I don’t suggest rearranging tool menus and so forth until you settle into a comfortable work style. Just wait until you want to make it a bit more convenient to your work habits. Definitely you can have it your way.
I thought I would miss the 4 view display I have in Rhino, but after working a short while in BobCAD-CAM, I didn’t even think of it. By the way, I will refer to Rhino occasionally here, not as a recommended alternative but as my basis of comparison. Rhino is a great 3D CAD and graphics program that I know how to use. You have to buy an additional add-on product to do any CAM with it. Actually BobCAD-CAM is very happy to import Rhino files.
The switching between various windowed axis views works fairly well but I did occasionally notice a few missed quick clicks when changing view, especially going into the rotate view.… Continue reading
Getting BC-C Loaded without C2H5OH
The BobCAD-CAM (BC-C) package arrived at my home office on a Friday, just a few days after shipping by UPS from Clearwater Florida. It is version 24 which is the latest and I presume greatest. It is a two disk set which is one disk of training videos and instruction manual and the second disk is the actual program install disk.
Unfortunately the instruction disk refused to load and run any of the instruction videos but the PDF manual could be opened and read. A NERO disk scan confirms the disk is bad. The salesperson and support desk at BobCAD-CAM are sending me a replacement disk. The same video training is also available from the BobCAD-CAM web site but of limited resolution, perhaps because it is directed from a YouTube server with JWPlayer. The quality usable but I am expecting the disk version to be of higher video quality. I will let you know.
Update: BobCAD actually send me both disks (new) because of the defective Disk 1. I ran all the training videos and they are exactly the same content as available on the web site but of superior quality. They wouldn’t go to full screen of my 24 inch monitor but were very sharp and easy to view. Nicely done.
So the new owner is not dead in the water on getting started with training. It is good the BobCAD-CAD web site provides a backup not only if the supplied training disk is damaged as is mine; it is also a great way to get a preview of the product before you make a purchase.
I have one other slight issue in getting started, and that was due to the packing invoice not included in the box, a shipping clerk oversight. The invoice contains the serial numbers or… Continue reading
Letting the Cat Out of the CAD
I am taking an opportunity in my project schedule to try another CAD/CAM package. I had looked at it long ago and it has been around for over 25 years. When I first saw it (back then) I believed it was one of those,”yet another CAD/CAM packages.” I am sure at some point I registered and ran at least the demo, as it seems I have been receiving occasional marketing from them forever. Back in that time, I was looking for a cheap all in one CNC solution. I was still a bit naive of all the requirements. I did find and purchase DeskCNC with its serial port interface. That worked OK but I am now using much stronger and expensive Rhino and Vectric 3D software and MACH3 from ArtSoft. You get what you pay for.
The product to which I am now referring to is BobCAD-CAM. I knew it was created by a guy named Bob (Bob Twaalfhoven) so I assumed he just called it BobCAD after himself. I was thinking simplistically it was Bob’s CAD. Today it is a more professional play on the image of a Bobcat, just change the T to a D. Whatever the thought on the name, it has survived the test of time.
Soon I will see if it survives the test of Dan.
DeskCNC is still around too but the web page has changed little to none. BobCAD-CAM is on version 24 and a first web site look, while allowing for marketing hyperbole, seems impressive.
It will take me a few weeks or a month or so to give it a full workout and use it to construct a CNC project. I’ll probably leak a few comments here in the blog, but I am considering doing a full report, probably… Continue reading
4″ Mayan in Wax
I use the Mayan calendar as my CNC test program. It is highly detailed and makes the stepper motors really earn their keep. In these photos I show where I have reduced the circle diameter to just under four inches. This is about as small as I can go with this design. I got it off center a skosh. That’s OK, it’s not a keeper. The test is not of the Taig mill but rather the tiny wax profile bit I bought from Bits & Bits.
The bit is 1/8″ in diameter half round with a 15 degree included angle. The end of the tip is 0.005″ It looks and feel like a very sharp needle. The RPM was 10600 (max for the stock CNC Taig) and the feed I had set for 30 IPM. With ramp up it seldom got to 30 IPM except for long paths.
The total run was just over four hours. The Taig and CNC controller took this run without a blink.
I use plain air to clear the wax chips but you can see they still liked to stick around. The problem could be the slow feeds because of the intricate details. I am going to try a faster more aggressive feed on the next Item. I am thinking of trying a small lithophane carved in wax.