Re: [CAD_CAM_EDM_DRO] WHICH CAD AND CAM SOFTWARE PRODUCT WOULD YOU RECOMMEND FOR MY APPLICATION & WHY?

Eric Mack wrote:

> The problem with posting this type of question is that it provides no
> qualifying information for you to consider when replying. I know that
> many folks have asked this question before with mixed responses. I'd
> like to encourage answers to this question that will help other
> newbies like me who I am sure, are dealing with the same question.
>
> So, what that said, I will first qualify my situation and then
> welcome the responses. My intent and hope is that this will trigger
> many responses. I have cross posted this to the Sherline group and
> the CAD/CAM DRO Group as I am involved in both, and, while the
> Sherline folks may (or may not) be as involved with CNC, the answers
> to the CAD question will certainly prove valuable to all.
>
> OBJECTIVE: My objective is to be able to machine small parts for
> robots that I would like to build. These parts include mounting
> plates, brackets, gears, parts for grippers, pulleys, cams, etc.

OK, these sound mostly like 2-D parts. That helps define your needs.

>
> EQUIPMENT: I have a CNC Equipped Sherline Mill with a rotary table
> and an AHHA Controller. I will also have a CNC Equipped Sherline
> Lathe with a linear encoder for threading. Finally, both machines
> have a spindle motor controller.
>
> CAD SOFTWARE: None, to speak of. I have downloaded various demos to
> experiment with. It looks like I will have to gain much more
> experience to be qualified to choose one. While the vendors are
> generous in allowing 30 day free trials, I'm concerned that I'm not
> able to learn enough in 30 days to be able to make a decision on a
> package that can cost upwards of a thousand dollars.
>
> CAM SOFTWARE: Again, None to speak of. I would prefer a package that
> has the CAM functions built-in unless there is a reason that I should
> not be considering this approach. Otherwise, see notes above.

I agree with you here. I went with Bobcad/CAM for this reason. I didn't
want to have to do the research and testing to make sure that the CAD
and CAM were completely compatible.

>
> CNC SOFTWARE: The CNC Controller that I have is based on an AHHA
> Controller.
>
> EXPERIENCE: I've been more computer oriented than mechanically
> oriented most of my life. While I have no trouble putting things
> together or designing things, I have only a small, make that tiny,
> amount of hands-on machining experience. I understand the concepts
> and I have been reading many books on the subject. So, while I am not
> afraid to make shavings, I know enough to know that I need to be
> pointed in the right direction when getting started.
>
> LEARNING STYLE: I don't mind reading. I also value experimenting with
> what I am learning. For that reason, I am collecting a pile of wood,
> plastic, and aluminium blocks to make shavings from. I also enjoy
> videos and watching/learning from others who are more experienced
> than I am. I share this as some folks prefer to learn by doing vs
> being taught. I'm game to either method.
>
> FIRST PROJECTS: I took a handful of unique parts from my LEGO
> Mindstorms kit. These include blocks, pulleys, gears, and the like.
> My current thinking is that I would start with a basic piece such as
> a block and try to design it and then plan the tool path to machine
> it. I would reproduce this part until I get the process right. Then,
> I would proceed to the next part. I like the idea of trying to clone
> some LEGO parts as I can then use the real parts to see how well
> things fit together. By the way, if any of you have a similar
> interest in taking this LEGO approach or have others ideas, I would
> like to hear from you.
>
> BUDGET: Although this is a hobby, I like to do things well and I want
> to learn how to do things right. I have invested a lot of money in
> what I believe is good quality miniature machining equipment. I am
> pleased with the conversion. Now, I have the enormous task of
> learning how to produce parts with all of this stuff. So, while I
> would of course like to spend very little, I'm also willing to invest
> enough to do it well. Is that $500, $1000, $1500, More? My intuition
> tells me that I'm probably looking at about a $500-$1000 purchase by
> the time I add 4th axis support. I know that there are some excellent
> no-cost products like Intellicad. There are also multi-thousand
> dollar products intended for the Professionals who do this for a
> living.
>
> Ok, so, with the qualifying information here comes the big question:
>
> "BASED UPON THE ABOVE QUALIFYING INFORMATION, WHICH CAD AND CAM
> SOFTWARE PRODUCTS WOULD YOU RECOMMEND FOR MY APPLICATION AND WHY?"

I'm pretty sure Bobcad/CAM can't handle the 4th axis in the general
sense. IE, if you had a drawing of a complex 3-D surface, it would
not be able to use the 4th (rotary) axis to machine all sides of it in
one program. I'm not sure you can afford a program that can handle
the fully general case of this. I'm also not sure you would ever need
to, given your objectives, above. The one place a rotary axis could be
VERY useful is in making gears. The best way to do this is to cut a
single point (or multi-point) tooth profile cutter, and then cut the teeth
one at a time, with an indexing of the rotary axis in between each pass.

If you want to be able to make any imaginable shape, without much
prior thought about machinability, or hand manipulation of the G-code,
you are dreaming, or have the budget of Bill Gates!

I did some analysis and thinking about a pet project of mine, to take
photos of people and then machine scaled busts of them from the
photos. I found out there was software to do the extraction of point
clouds from multiple photos, but that such software had real trouble
with faces. The software worked REAL well on buildings. Faces aren't
too hard, and I figured I could just rotate the stock and make axial
passes up and down the piece. But, for parts with deep recesses
and intersecting flat faces, it gets a LOT more complicated to produce
the correct toolpath without skipped or gouged spots. In other words,
mechanical parts are a lot harder to deal with, as they may have more
discontinuities. But, I think you can go REAL far, without getting into
the 4th axis very much. The one place you can use it is in making
rotationally symmetrical parts, like gears and belt sprockets. in that
case, you make the CAM program just do the notch between two
teeth, then you add in the code to index the rotary axis at the end
of the program.

Jon