Trying to use conforming vectors again

[luckettg]

I bought this upgrade when it first came out, tried it a couple of times, getting weird results. Mostly it was carving crazy, not moving like it should, etc. I moved the text out of the pocket with the pattern, just cutting text above and below and it worked fine, every time. Wasted a lot of wood back then, playing with it.

I decided to try it again when a customer asked me to make him a design that needs it. My first run at it, it again went nuts, right at the beginning during the pocket carving with the 1/16 ball nose. The X and Y axis seemed to be moving right, but the Z was bobbing up and down. I am attaching the mpc file and the picture of the board. I aborted the carving.

I have been looking it over and cannot see anything wrong with the design. I am carving a modified one of it now. It cut the pocket and the pattern okay, but then when reinstalling the V bit, it gave the error msg about not finding the correct depth. I reinstalled that, then same thing, so I gambled and told it to continue anyway. Usually that creates a mess with the text, but this time, as it is carving at the moment, it looks okay in the bottom of the pocket. When it is done, or I abort it for some reason, I will include the results. The mpc file is also included now for it.

I will report more in a bit.

[luckettg]

Well, it worked pretty good; the best it ever has for me. It did not carve the text on the Hero's Engine very well, but the other text will work. Deeper would have been better, but that has always been a crap shoot with fonts and Designer. No depth control settings at all. I used the 1/16 ball nose and the 60° V bits.

[SteveNelson46]

Greg,

The machine will ask for all of the bits used in the project in the setup and measuring cycle at the beginning of the carve and then again as each bit is used. The error message "Bit Depth Does Not Match" is usually caused by the bit that hasn't been inserted to the same depth as the first time it was measured. Are you using stop collars to insure the bit is inserted to the same depth each time? It has to be inserted to a depth that is within the acceptable range and to the same depth each time to avoid the error message and air carving. Also, the bit has to touch the bit plate each time so the depths are set correctly.

[luckettg]

Well, it worked pretty good; the best it ever has for me. It did not carve the text on the Hero's Engine very well, but the other text will work. Deeper would have been better, but that has always been a crap shoot with fonts and Designer. No depth control settings at all. I used the 1/16 ball nose and the 60° V bits.

[luckettg]

Darn, lost my reply to you Steve. I will try it again.
I know about how to install bits and the errors that are caused by not doing so correctly. This is not the case, but thank you for the suggestion. I have had this machine since Dec. 2007, and have both upgraded and rebuilt it several times. This error was caused by something other than miss intalling the V bit. Every now and then, since day one, the machine will give this error, and it is always with a V bit. Those are really hard to not reinstall correctly, so I have my doubts. My guess is a software glitch that measures the original operation, then does not do the calculations correctly when reinstalling the V bit.

Connie suggested I should also do another calibration check, but for a different reason. That had to do with text depth. It is a good idea, so that is next on my list.

The X axis has been having issues since putting in the rubber traction belts a couple of years ago. Intermittent in nature so I suspect board variances are causing that.

Again, I thank you for trying to help me. I appreciate that. If you have any other ideas, please let me know.

[DickB]

The Centerline tool is for the 90 degree V bit and 60 degree V bits only. You selected and used the 1/16" ball nose bit for the text on the Hero's Engine - that is why it turned out so poor. Try again selecting and using the 60 degree V bit for that text.

Asking for a depth control on Centerline is asking to change the laws of trigonometry. The Centerline tool manages the depth of cut to yield the width dictated by the width of the text strokes. The only way to go deeper with a given V bit is to go wider on the text strokes, by selecting Bold or a different font with wider strokes:



Or select the 60 degree V bit as you did. That bit will cut deeper than the 90 degree bit given the same font and text size (stroke width):

[luckettg]

Yes, I know how the text and depth is related and based on the angle of the bit. What I have a very difficult time with is how to determine the actual font width versus the actual cut depth. It will look fine in Designer, but that is just an illusion. I also run a Shark flat bed CNC, and do have depth control there, so it is not a simple matter of trig laws being not understood on my part. There are a lot of fonts to choose from in the drop down menu for the text, in Designer, yet no good way to determine the width or the depth. I might be wrong and just ignorant, but I struggle with it.

Using the ball nose for text was just an experiment, as it is in the drop down menu for selecting the bit, in Designer, for the text. If only the 60° and the 90° V bits should be used, why are all of those other bits selectable?

Thank you for the suggestions. I appreciate your effort to help me. Any ideas or suggestions are good.

[DickB]

It will look fine in Designer, but that is just an illusion.

I don't agree. Designer gives a good representation of the end result for me. If the result is not as illustrated with Designer, I suspect it is because of some kind of machine problem.

What I have a very difficult time with is how to determine the actual font width versus the actual cut depth.

There are a couple of ways to do this. With the 90 degree bit, the depth will be 1/2 the width of the stroke. Draw a line across the stroke to make a measurement and read the length of the line. Even easier, place the cursor over the center of the stroke and read the depth at the bottom of the screen:

I also run a Shark flat bed CNC, and do have depth control there, so it is not a simple matter of trig laws being not understood on my part.

Are you using Vcarve Desktop software? I'm not very familiar with that software, but while you can set the depth of V carve text, I believe that is used to generate a toolpath in a recessed area to produce a faithful version of the given text. If the depth setting doesn't match the depth of the surface, then the resulting character is deformed. I'm not sure why you would want that. The depth setting in Vcarve is not bending the trig laws. Using an incorrect depth setting will distort the text. In Designer, Conforming Vectors makes this depth adjustment for you, preserving the shape of the text. It's true that in Designer you cannot specify an incorrect depth to yield distorted text like you can with Vcarve.

[luckettg]

I suppose we will have to agree to not agree on your first point. I am using the latest Designer versions, always have, along with most of the add on packages. I completely disagree with you about the fonts looking like the way they actually carve.
Second point, I will give those two ideas a try, and run some test carvings, thank you.
Third point. I use Aspire, which is a souped up Vcarve. You are of course right about what happens when not set correctly, but I can tell if I am doing something the machine will not like, usually before actually carving and finding the mistakes by wasting wood and carving time. I really like being able to set feed rates, bit rpms, and a wide selection of bits to choose from, even setting up new ones. I use Aspire to create 2-1/2D PTN files too. Export from Aspire into STL to PTN.
We have digressed from the conforming vector discussion, my fault for mentioning what Connie and I were discussing about text. That first carving that went whacko, I am still unsure why. Spent more time on it in Designer last night and will do another carving today, after I double check the machine calibration. I will report what is discovered.
Thanks for the discussion and the methods for text sizing to try.

[SteveNelson46]

Aspire doesn't really have a depth setting either and the same rules apply. What it does have is a start depth and a flat depth setting. This is the same as Centerline in the Designer but with much more control. The start depth setting allows for a v-carve in a carve region or pocket or even on the surface of the board and if you want the bit to carve a little deeper just set the start depth a little deeper. If the Designer had this setting one could play with the start depth to diagnose a problem and compensate, within reason, for fonts that don't carve very well.

On most CNC machines how deep the bit is installed doesn't matter as z-zero is set only once when a bit is inserted and used. If no bit is inserted at all the collet will touch the surface of the board or z-zero plate.