Re: [CAD_CAM_EDM_DRO] Contouring and CVV was Re: DeskNC for Windows experience anyone?

Ballendo,
I had to print out your view on Contouring. I will need to sit down and
analyze some of what you said.

In the case of FlashCut, I can only assume that it does indeed use the
technique that you mention as trajectory planning. It does indeed evaluate
the toolpath and make some pre-conclusions on just what paths it can run
without ramping, and which ones it can run by adding an adjustment in ramp.
Best I could ever tell, this is accomplished by two main factors. First, it
is based on a maximum unramped feedrate or rather the settings you make for a
maximum start/stop motor speed. Secondly, is a setting that you indicate as a
Continuous Contouring Feedrate tolerance in ipm. How it determines what
angles to run at that tolerance I do not know.

Now after having retro'd Flashcut to a few completely different machines,
with completely different drive ratios and amplifier/drivers, I will say that
I have seen quite a difference in operation. Some seem to run similar rates
very smoothly, yet others not quite as well. Obviously, this can be
contributed to so many things. This is where I feel it can be a situation
where some proudly mention their great successes with a product while others
indicate that it did not go so well. Thus I am very careful to not "Bash" a
product, but just tell of my experiences.

I would add that when I was hunting years back for a product with Contouring,
there was little available around $1000. My very first retro was with
Indexer. (Actually, there was one project before with MicroK DOS. This is not
for a Flatbed Router) I did two machines with Indexer and had good results
with it's Contouring Technique. I do not recall what settings were adjusted,
but I do not think it had anything to do with angles of approach. Whatever
techniques were used, it worked very smoothly, obviously analyzing the
toolpath very carefully for optimal execution. This was back with version 3.
The lack of G-Code capability sent me on the hunt for a new program, and
"Windows" is where I wanted to be.

Luckily for me, we had bought a brand new machine at work (flatbed router),
from a company (I will not mention), that flat out did not work. It was their
first attempt at their own controller. Somehow, a salesman convinced my boss
to buy it. It sat for a few months while the companies tech and sales force
tried to make it do what they said it would. Finally, I was able to convince
those in charge that we should retrofit it.

After some searching and looking at a nearby machine, I opted for the Ah-ha
setup. The Ah-ha setup sure was capable of doing many things. It ran that
machine for about a year with absolutely no problems. Rock steady, very
trustworthy. But, this was doing generic jig making. Straight Lines and Arc
commands. This was fine until we needed this machine to run thru mixed
geometry and short line segments. Ah-ha came out with their contouring option
but we could not run it much faster than 30ipm without it stuttering all over
the place. In conclusion, The Ah-ha computer card was shelved for later use
on a mill. I am sure for most work on that machine it would have been
wonderful.

The next step was to retro FlashCut, the newcomer at the time. Woulda went
with that right off if I knew about it. We hung it on the Ah-ha drivers and
it ran like the wind. Well, not right away anyhow. This was back before Flash
even had Contouring. But it still outran the Ah-ha as the time delay between
steps seemed shorter. The machine was just as trustworthy as it was under
full Ah-ha control, but now I was finally able to ditch using those worthless
floppies (CR101-CR101-CR101) and run this thing on the network. Draw-Post
thru the network- Cut ! Excellent !!!!!

However, The most impressive part about the FlashCut program was and STILL
IS, here was a proggy that "never had contouring considered" in the base
code. We called and developed a relationship with Flashcuts Gurus and worked
close with them uncovering small quirks while Contouring was being
implemented. Other small changes in the GUI, key commands and all around user
friendly updates were made at our request. In fact a lot of things were added
or changed though e were not the only ones asking for them.

This is where FlashCut's personel applied the most important business rule:
They listened and responded to their customers. I can not say that to be the
case with many of the others I worked with. There was a lot of discussion,
but not always action. In fact some of those companies are only Now applying
a Windows Control!

Do I feel that FlashCuts contouring lives up to Indexers ? Not quite. But,
then again, it sure isn't bad for a program that didn't have it at first !
Base code for the 16 bit program had always dictated any limitations it has.
I for one look forward to having seperate ramp/accels between Jogs, feeds and
rapids.

What's on the horizon with new products? I can not say as I have not used any
new-comers products. I have a keen eye on Master5, and. I have heard good
things. Likely this will be where the hobbiests modern software will be
found, especially at that price! I know I will purchase it when I see the GUI
change for a smal engraver project. I have heard both good and bad about
CNCpro. I assume the bad is based on one of those users that just could not
figure out how to make it work correctly as far too many indicate that it
works excellent.

As far as Flashcut, Well, lets just say that there are good things in the
works for their company. They used their business "sense" to secure good
relations with many OEM companies that were longing for a decent Windows
based software. That has turned into private labeled products. Their new 32
bit version due out in the not too distant future will likely turn out to be
THE answer in a $1000 dollar control. It won't be for everyone at that price,
but, business is business. They have to pay the bills. And, I am equally sure
that there will be those who will continue to conclude that they absolutely
have to have a $15,000 dollar controller and everything else is junk
especially if it is PC based. To me, computers are computers. If you can't
keep windows from crashing...... It must be a personal problem. I have not
ever wrecked a part because of a "Windows" problem. SO there !

Well, I'm off to read and absorb your Contouring Masterpiece!

Seeya,

Chris L

ballendo wrote:

An incredible thesis on Constant Contouring............