[MetLHead]

I do all hand coding using cad drawings as a reference tool. All the parts I have to do are relatively simple, just turned and bored, and threaded on our Lathe. So I don't think we are going to purchase a cam $y$tem (sic)
I just hate having to go to the lathe for backplotting...

Is there a free or cheap backplotter for CNC lathes ??? Everything seems to be
made for CNC mills.

What I do like about hand coding is that I am becoming very familiar with all the codes and canned cycles, and I can control tiny little details...cuz I am a control freak ><;

Check out www.ncplot.com

It has a basic lathe backplotter, but there's no canned cycles for lathe yet. I'm still working on this, I should have them ready for the next beta release.

Regards,
Scott

[Brian J]

Depends I program both in cam and by hand depending. Parametric programs almost entirely get written by hand. Cam provides a good template though if you have multiple programmers so that the code is in the same format when it comes out and if multiple controllers so that the little diffences in some of the cycles don't cause headaches, ie G76. Also makes it easier to troubleshoot on the floor if you know where in a line you are looking for info. Still end up editing cam posts to remove some of the wasted motion you can't edit out of the template files. Have to agree though the more you use the cam product and get familiar with it the faster you become with it.

[NeoMoses]

mostly CAM, but I continuously edit programs that I frequently use. I find that each time I run a program, I find another spot that I could speed it up. I also become more comfortable with seeing tools rapidly approach workpieces, etc...

CAM for quick and dirty stuff, hand edit for optimum speed.

[Somle]

99.7% by hand. Directly on the machine (Okuma MC-400H). It is an older machine, so it can't read MS-DOS formatted floppies. We have newer machines that can read both MS-DOS and OSP-Formatted floppies, which can then be used for copying programs written or generated on a PC.

Guess i should be overly happy by doing it all by "hand", but it is slow and generally lots of errors/typos. Good for making some smaller programs, like a few holes, threads ,
simple facemilling. We had edgecam a few years ago, but gave it up since the one who could use it left, and it costed quite a bit to use (yearly fee or something), and we didn't use it enough to cover the cost, .. or so they said. And it generated very large programs , which the little memory on the okuma had a hard time to digest.
No parametrics i guess. But the 4 - 9 jobs we used it for turned out very well. Now and then, quite often actually, i wish we still had it. Or something simular.

[grabadosjapansa]

Just curious how many write to Cam, Me I write it.

Hello,
I make wood carved reliefs, it's impossible to write the Gcodes by hand. My works are too complex for that! In the mechanical industry I wrote some Gcodes by hand.
Regards,
Juan Sanchez.

http://www.geocities.com/grabadosjapansa/index_EN.htm

[bsharp]

I Use Cad\Cam every day. I use cam because it will not make a mistake where as if I write the code myself I may make a simple mistake and it then would cost me money and even more time than doing it with cam. Genarally if you can hand code it faster by hand you need a better cam or more training with it. Elimination of the posibilitys is all. "The old saying an ounce of prevention is worth a pound of cure.

[musicmkr]

I used a cam package to develop some code that I will need to run over 10,000 times in the next few months. The CAM version ended ran at around 14 minutes per part, way too slow.

I started from scratch, and hand coded it. Now it runs at just under 4 minutes per part.

[imserv]

My Cam system tells me how long the part will take to cut and how long each tool will take. It's easy to see if I did something dumb ( like use 5 ipm instead of 50) before I try to cut the part. It will also simulate the milling process on screen as an additional check for reliability. I still usually optimize speeds and feeds at the machine, sometimes forgetting to record the best values for re-use the next time the same part is made.

Fred Smith - IMService
http://www.cadcamcadcam.com/hobby

[Geof]

Musicmkrs example demonstrates what has been referred to by a few posts; hand coding can produce faster running programs than cam and a lot of people edit their cam programs to optimise them. I think the dogmatic claims that cam is faster, better, easier for everything are wrong. Sometimes cam is the only way; nobody can write a multithousand line program for some mold shape or engraving a picture but if you know the geometry of your part you can hand code complex shapes; years ago everybody did this. Those people who came into the trade 20 years ago and did learn good hand coding skills, which they now apply to editing cam programs, are doing a disservice to newcomers when they say do everything by cam. A fully competent programmer needs both so that they have the knowledge and experience to edit and optimize cam programs. Also just looking at the time to create a program is wrong; the correct time period to look at is from when you first get the drawing, dxf file, or whatever to when the last part comes off the machine. A short run of a complex part almost certainly is quicker overall with cam but a long run may be quicker with hand coding. And the difference is often not just speed and feedrate selection, cam often introduces redundant toolpaths and sometimes it is quicker to write the entire code by hand to run faster than it is to spend a lot of time finding these and editing them out. But if a person has only used the cam approach and never done any significant hand coding they have no reference point to decide whether a part is complex and what can be done to optimize a cam program. My suggestion to people coming into the trade is; if it is possible to hand code, in other words if the part geometry can be calculated using trig in the same manner it would have been done 20 years ago, do it!!! Learn the complete capabilities of G codes and CNC machines. Sure you might have to spend some of your own time writing programs that are not needed because the cam generated program is cranking out the parts. The thing is you have two programs to compare and can learn the advantages and limitations of both approachs. You might finishing up knowing more than is needed for your current position but I can assure you knowing too much is a whole lot better than not knowing enough.

[mrainey]

Geof,

Great post!

[Kool Parts]

100% cam with hand editing.
Gary

[Halfnutz]

I still have no clue how to use a drawing or cam package. I have two beutifull cnc machines but they are limited to engraving work with DeskEngrave and because I cant figure out where to start when I open up a CAD or a CAM program. People often say to take the time to learn CAD/CAM, but I have yet to figure out how to do that or even where to start. I can make anything I need with a rotary table and a manual mill or lathe and the right tooling, but couldnt cut a square with a hole in it if I had to do it with CAD/CAM.

Some day I'll learn more, but I geusse I need a course or a book to explain it to me. I have been unable to figure this stuff out with the manuals included with the software. Most CAD or CAM manuals explain how to use thier software, but assume the user knows things that I am clueless of. For instance, the manual for ACEConverter says "load a DXF file into the program that has includes your tool path data." OK, but whats a toolpath? How do I produce a DXF file from my CAD program with the toolpath data? Other programs work without toolpaths, now I need to have it.

Thats an example of the type of frustration I have experianced trying to learn CAD/CAM. I know how to program, so I geusse If I had to I could write a program with just G-code, but by the time I wrote the program I could make 6 of the parts manually. Any one know of some FREE ways to learn the concepts of this stuff?

So anyway, what exactly is a toolpath, how do I write them, and where do they go?

(The above comments are the authors and do not represent the opinions of CNCZone or its management.

[HuFlungDung]

Wow Halfnutz, you sound really lost with cadcam. What kind of cnc machines do you have?

I would recommend that you browse the Haas website. They have a lot of material on there. While it is geared towards the user who is learning to run a Haas, much of it has universal application, assuming that your cnc is not too far off the mainstream in the way it is designed to be programmed.

A toolpath is simply the mathematical equivalent of cranking the handles on your mill table to arrive at coordinates. You need to understand what a 3 axis coordinate system looks like, and how any point in space can be described by one and only one coordinate, having X,Y and Z values that correspond to the hypothetical axis system.

It is always easiest to assume that the XYZ system has its origin (zero values for all three axis) at one corner of your part, if it is a cube shape. Sometimes, we need to imagine there are two coordinate systems, one belonging to the part, and one belonging to the machine. The two coordinate systems have the same orientation in space, but are simply displaced by a simple offset. Then we need to know how to compensate for this offset.

The toolpath is simply the safe coordinate locations for the tool to move to, outside the part. Obviously, if the tool moves through any space occupied by the finish part, you have cut a gouge through the part.

If the size of your stock is larger than the final desired part, then obviously material must be removed from the part. The fact that the tool you will use has a diameter of some value, means that the path for the tool has to maintain a fixed distance from the actual final part surface. This fixed distance equals the radius of the cutter. The cam part of the software creates lines and arcs that are offset from the part by exactly the correct amount. The lines on your screen representing toolpaths really are only for your visual benefit. The machine only needs the start and end coordinates of the lines and arcs, plus one of two possible choices:
Start here and move in a straight line to the next point (machine code is G01)
or
Start here and move along an arc to the next point (machine code is G02 or G03).

Now the cad part of your software deals only with the drawing of the part, or model, geometry itself. If you use solids or surfaces in your cad, this is obvious. If you draw only "wireframe" cad, then you have to imagine that your lines and arcs define the edges of the surfaces that you intend for the model to have. In such a case, then either you, or your cam system has to offset from the wireframe cad model, by the radius of your cutter, and create a "skeleton" of toolpaths which will cut away all excess stock.

[ger21]

For instance, the manual for ACEConverter says "load a DXF file into the program that has includes your tool path data." OK, but whats a toolpath? How do I produce a DXF file from my CAD program with the toolpath data? Other programs work without toolpaths, now I need to have it.

What ACE considers the toolpaths, is just lines and arcs. All you need to do in your CAD program is draw lines and arcs wherever you want the tool to go. Save as .dxf and load it into ACE.

Say you want the tool to cut from 5,5 to 15,2. Just draw a line with those coordinates, and ACE will turn that line into g-code to move the tool to those positions.

A book or online tutorials is probably the best way to go. What CAD porgram are you using, btw?

[Kool Parts]

Halfnutz,
You sound a little like me when I first started. I received my first machine (Brand new VFOE) and a Compaq computer the same week. Had never wrote 1 line of G code in my life, and had never pushed the on button on any computer. I obviously had no fear and no sense back then!

Then the hard part, a "friend" recommended bobcad as a easy solution to get started. After 2 weeks of despair I somehow found a surfcam dealer that would come to my shop and teach me cad cam. It was hard to part with $5500 when the other systems were so cheap, but the difference was hands on teaching.

Now there are lots of good cad cam systems, but what you need is somebody to sit down and show you the basics. It will make all the difference in the world.
Gary

PS I beat the crap out of the friend for his recommedation :boxing:

[Halfnutz]

Yes, I need to take a course at the comunity college. I just havent been able to yet, and trying to do it ad lib is just too time consuming. I will try out the tool path example you gave me though, Gerry, it sounds simple enough.

I'm not desperate or worried about it though, I can do signs and plaques with deskEngrave, then I do the borders manually with a router, so I do use the machines. And I can make whatever I need manually. It would be nice to learn more about CAD/CAM though.

I have a copy of TurboCad, and its fine, I havent had time to teach it to myself yet, but I will. I'll probably get thier TurboCADCAM eventually, but in the meantime I would like to learn how to do this stuff with ACE. I dont have the bucks for a CAD/CAM package right now.

Ive only been doing this for less than a year, and Ive made two machines so far, so I have learned quite a bit, just not as much and as fast as I'd like.

How 'bout a 24 year old female CADCAM tutor named Bambie to sit on my lap while I struggle through this....................

(The above coments are the authors and do not represent the oppinions of CNCZone or its management.)

[Victor Martin]

I dont have cad yet,We are a custom hydraulic Cylinder manufacturing shop and still do production jobs rarely.I think I will need cad once I master my turning ctr.Which is better Shopcam or ezcam?both of these are cheaper than Featurecam.Is there any shortcuts like templates that could save me time w/o cad cam?I have Fanuc 6t control and 1982 wasino l5- j3.

[Kool Parts]

Victor Martin,
Not familiar with either of them. Or with Surfcam lathe package for that matter. I have had all mills up till now. But with a new lathe on the floor I think I will get Surf lathe just because I know the mill side so well.
Gary

[Gunner]

I think doing lathe programming is much easier by hand. You run into to many variables that are difficult to handle with cam/post processer and end up playing around with the program at the machine to get it right anyway. Simple stuff for the mill is easier by hand too although I have written posts for a lot of the simpler stuff that works pretty well. I will say that when you have a lot of combined radius and angle work a cam system can help with the numbers you need. Once you get those, a text editor is all you need.

[miljnor]

hey halfnuts, you look like you in orange county. If so just PM me come by my shop and I can probably point you in the right direction. Most packages have some similarities I personally use virtual gibbs which is a nice package. dont know what you use they all have their pluses and minuses but between me and the guy that works for me we could probably point you in the right direction. We can probably only help if your not affraid of the stuff though

Of course it could just mess you up more!