CAD/CAM/CNC
Milling Wax Adventure
The year is running out fast. I will soon have to say good-bye to 2011. This is the year (last Saturday actually) that I became 65 years old. Time enough for pondering that event, now to keep moving. Ha!
I did some machining of wax on the Taig CNC mill Saturday. I love machining wax (the hard blue kind). The wax is not good for creating real finished useful items but it makes excellent models for making molds and doing casting.
I spent the morning doing the design work in VECTRIC Aspire software. I was creating a Christmas ornament as a negative. I learned how to mirror and reverse the lettering and other “thinking inside out” processes in 3D design.
The afternoon was spent machining the design into the wax, using the Taig CNC mill. That was an adventure.
I haven’t run that machine for some time. The milling started out OK, but I got a couple of stalls and lost steps in the Z axis. The mill has never done that before so it was a surprise. I wasn’t pushing rapid travel or cutting speeds that hard either. Lifting the spindle and motor is fairly hard work.
The rapids are only set at 65 IPM and I was running about a third of that. So I ran through the software set-up and MACH3 warned me I was pushing the limit on pulses for the pulse generation frequency for which I had MACH 3 set. The Taig has twenty TPI screws so it takes a lot of very short pulses with 1/8th stepping (32,000 per inch) to get any speed from the drives.
That’s 32,000 per inch so at 60 IPM travel (keeping the math simple) that’s 1 inch per second requiring 32,000 Hz (32 kHz)… Continue reading
GWizard – First Looks
A visitor to this blog named Bob Warfield left a comment about a post he made in his blog HERE. Bob is also the creator or progenitor of machine shop “Speeds and Feeds” software called GWizard. It probably isn’t fair to call it just a Feeds & Speeds as it does so much more.
Bob told me he was known for The CNC Cookbook Blog as well as anything. So naturally I had to dive in and take a look. Sure enough there was Bob standing there grinning and holding plate with pumpkin pie. You’ll probably have to scroll way down to find him now (and the pie). This CNC Cookbook is a great place to read and study about the “science” of rotary machining.
I like a guy that doesn’t hide his face from his peers and customers.
I perused carefully everything I could find on that web site. Where was this when I needed it!? Of course always the skeptic, I had to figure out what was the “deal” going on here. The biggest question for any CNC machinist (well at least for me) is how hard can I push feeds and speeds and what are the reasons. It would seem obvious that this sort of program would have been offered long ago. But… it is a very complex subject. Tool manufactures are of course going to shade any such tool program toward their own products.
Bob admits it could be done with a spread sheet and in fact that is how he started. When I first started CNC machining I eventually found the safe speeds for the kind of work I usually do, but it had taken a lot of effort. I could have built a spread sheet myself but the effort would have kept… Continue reading
“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