From Drawing to Part

[john_r]

Hello all,
I was wondering how do you go from drawing a Corel Drawing to a finished part? I have the latest software from SB and Corel Draw12.
I save a pic as a DXF and try to convert it then run the simulator and...It looks nothing like I drew. When I open the editor there is nothing more than a couple move commands.
So what am I doing wrong?

[paco]

You need the CAM part in between... Are you using the SB built-in converter? CAD drawing and CAM output WILL be different... but you should be able to "see" your part in those lines... (the lines you see in simulator)
Provide with more info to get help from here...

[john_r]

Yes I tried using the SB built-in converter. It has the pop up that says DXF file conversion sucessful, So I re-open the new file that has the.sbp extension and it doesn't look anything like my part, When I try to simulate a cut. Even a simple box or circle doesn't work. What am I missing? I bought my shopbot used and it didn't come with any software. It's a PR96 from 1999 and it has the rack and pinion. I haven't even set it up yet just trying to get some of the software down.
Thanks for your help.

[john_r]

OK I figured it out...
from another post. Corel's 0,0 is in the center of the page. SB's 0,0 ref is in the lower left quadrant. My parts weren't even on the table. Thanks Paco for trying to help.

[ron brown]

John,

Welcome to the forum.

Ron

[paco]

Aaaaah AH! I always re-edit my Corel drawing in other CAD software... Sorry that I did'nt remember to suggest about the centered reference... Are you getting what you want from DXF converter?

[john_r]

Thanks for the welcome Ron. I posted a couple of questions in the past before buying a SB. I will be setting my SB up next month and have been playing with the software for a few months. I'm not real strong on autocad but can get around Corel pretty good. And if the text in "Canvas" (an old Deneba product, not sure who owns them now) works I have about 5 years exp with that. But it doesn't have an option for saving as text or curves during conversion like it does in Corel.
Hey Paco, yes I'm getting the results I want now.
Do you guys find that using a cad program gives more precision to parts? For example if I do a measured part in Corel will it be exact VS what a CAD program will put out?

[bill.young]

Hey John,

If you type VP to open the previewer settings and then turn on "Automatic center", the previewer will zoom in or out so that whatever is drawn in the previewer will fill the screen. Some folks really find it handy and some don't like it at all...you might find it helpful.

You can also click the "Extents" button near the lower right-hand corner of the previewer screen...it's handy if you have a "lost" file that has drawn somewhere off the table.

Bill

[paco]

Corel is good CAD... but only 2D CAD... as far as I know!

[john_r]

Thanks for the Tips guys, I will certainly give it a shot.

[normand]

This is where you find link to zsurf4 .From a bitmap to 3dmesh in no time http://news2.mcneel.com/scripts/dnewsweb.exe?cmd=article&group=rhino&item=175765&u tag=

[normand]

IF this does not work I give up.
4065done in 2 minutes from text. zsurf work with bit map file also. I found this freeware in visualmill forum.

[ckurak]

Normand,

What are the steps to get that surface cut?

I found zsurf4, created some text, then "processed" it. zsurf4 produces a file called srf.igs.

What software can read the IGES file? (I do not have Rhino.)

Thanks in advance.

[normand]

Hi Charles I use visual mill it happen to work. I never heard of iges file before.There may be a iges to dxf converter somewere on the net.

[ckurak]

Thanks, Normand.

Now I seem to be more confused. In one of your previous posts you mentioned zsurf. I assumed that you created the "SHOPBOT CNC ROUTER CUSTOM WORK" text that you had in the photo with zsurf. So, I downloaded a copy of zsurf, created some text, and it saved a file called srg.igs. I tried to use FreeMill to import the igs file. It will not.
Before I spend some larger $$ on VisualMill, I am attempting to experiment with some low cost and/or free programs.

So, could you explain the process, please? What steps were taken with what software from text creation to part cutting? I'm not after a detailed explanation of what buttons to push or what exact settings to use. I need to understand what pieces of software did what.

From your last post it appears that you used VisualMill for the ENTIRE process, from text creation to toolpath generation, then saved something that transferred to the Bot. But, I'm not sure.

Thanks!

[Brady Watson]

Charles,
Zsurf is a neat toy, but most likely will never be good enough to make money using. ShopBot has a TIF to SBP convertor that converts a TIF file over to a shopbot part file using bit depth to create Z moves. You may want to try that as an alternative. You can do quite a bit more than ZSurf in Rhino3D. Rhino is CAD, and Visual Mill is CAM (toolpathing only). There are a number of other CAD and CAM packages out there and all of them offer a demo for you to try before you buy.

-Brady

[normand]

Hi Charles I am sorry to get your hope to high. The picture show the text in visual mill just after I open the igs file . It has not been toolpathed postprocess or routed yet.But from that point on it could be scale to the proportion I want then a first toolpath with a large cutter and then a finishing parralel pass with a small cutter could be done.This is not a tiff to sbp because it wont give you a .sbp file.It will output a mesh file from a bitmap , after that it is a virtual part that you process in a cam program.Rhino wont do what zsurf does. But I sure hope that rhino will do a lot more than zsurf considering the price.It is like comparing apple and a full lunch. I still think it is dynamite but you need the spark.
Normand

[ckurak]

Thanks, Normand and Brady!

So, if I have this straight, zsurf (CAD) is a freebie that can create Normand's text model in 3D as an .igs file. FreeMill (CAM) is also a freebie. FreeMill cannot take the .igs file as input. VisualMill (CAM) is a professional tool. VisualMill can import an .igs file. VisualMill can then be used to create the toolpaths.

From Visual Mill's webpage, I thought that it could create text. On their products page it lists "True Type Font Text" under the category of "Cad Creation / Editing Tools." Evidently that means that it can manipulate a TTF text object once it is imported from another piece of software? Maybe this is where I got confused.

VisualMill has a nice powerpoint presentation that walks you through their software functions. They also show a model toolpath for a visual representation of each function. I found this to be very helpful.

Brady, my interest in zsurf was more in lines of exploring something I have not done before. If I have a market demand, then a more powerful tool would be in order. If not, then I haven't spent thousands on an idea without an appropriate return on investment.

Anyway, I do know about the TIF to SBP converter. I've used it before. Works great. Of course, you need a TIF image file to start.

Thanks again.

[normand]

Zsurf is not a cad neither is Rhino but Rhino is 3d Zsurf is not 3d.I am a beginner at this to. Zsurf only take the bitmap and convert to vector(.igs)if you have rhino then you can further manipulate and transform the part.After that you need the cam program to make the toolpath and finally convert to .sbp file. Visualmill will write ttfont but I find akward to use and as of last month with the new update vmill wont write font under win98. meaning updating to xp, meaning a new computer to buy.Vmill is good the info could be better.
normand

[Brady Watson]

Charles,
You are right, you get what you pay for. I have experimented with a lot of different programs and my above post was basically telling you not to waste your time with ZSurf expecting anything other than a junky output. The SB TIF convertor is far better.

I believe that VisualMill's text fucntions are limited to machining text on a 3D surface and simple 2D raised text.

I've wasted a lot of money on software that doesn't quite live up to it's claims. Rhino and MillWizard are a very potent combination. I spent 5 minutes creating these files in Rhino and toolpathed them in MillWizard. About 7" XY and .25" Z:


4066

4067

[Brady Watson]

4068


4069

This took only a few minutes to do from start to finish. You can create a heightfield from bitmap in Rhino and export it in a number of formats. I made it an STL and imported it into MillWizard & machined with 1/8" ballnose in simulation.

If you want a nice combo, for about $1000, this is the one to get.

-Brady

[normand]

right you get what you pay for and you pay what you can afford. I would not let a car salesman nor Jame Bond tell me what ride to get.Charles I think you have to look at what you want to be doing first, and then decide what software to buy. What work for one might not suits you.Although rhino willwiz might do
Normand
Keep looking get many opinion

[bryan]

Brady what setting do you use on heightfield function in rhino? I have been using 150 by 150 on line with a neg 1 to 2 set to get a raised image. The picture is 30" by 15"
Does this sound ok? or should i keep them in proportion to the size?

Thanks Bryan

[Brady Watson]

Bryan,
I have found that a setting of 200 X 200 or even up to 300 X 300 will get you what you want. Set your Z height very low.

Here's a few other tips that will help. 1st, convert the image to grayscale. In some cases it may be necessary to convert it also to a negative image to get the male/female Z height that you are looking for. Try it, and you'll see the difference.

The default value on my machine for height is 10mm. I typically scale this down to 1.5mm and start there. You don't need much in Z to get the height contrast.

When pulling the image in, stay at a reasonable size on XY dimensions. It is not uncommon for the STL file that you export to be 60+ Meg in size. You really don't want to export a 3DS here, because 3DS by nature, are limited to a maximum of 64,000 triangles. STLs are not.

Keep in mind that you can also scale the X,Y and Z independently or together if you need to by using the functions under the Transform menu.

Let me know if you have any questions.

-Brady

[bryan]

Thanks Brady
I'll give it a try tonight after the day job ;-)
Now if the Millwizard people get my software here.

Bryan

[Brady Watson]

Also...Don't check the 'Interpolate surface through samples'...Use the 'Control points at sample locations' when you set Z-height.

Keep in mind that this and most 3D operations require a powerful computer. I recommend at the very least a CPU of 1.5GHz and 640M of RAM. Be sure to close out other programs when doing this in Rhino...or it may run out of memory.

-Brady

[paco]

This work great!!! I use a 1.29 GHz AMD Duron with ONLY 96.0 MB of RAM... and it's been fast (second) for a 8" X 6" X 0.2" Thk image relief (200 X 200)... I have been "problem prompts" as trying to save it as STL... so I saved it as 3DS... Here how it look for the simulation in Mill Wizard:

4070
Brady-
I have to ask you about how much time do you spend first to get comfortable with Rhino? Did you use something else than the inclued tutorials(training CD, books and manuals, Rhino forum)?

[Brady Watson]

Paco...Time & necessity has prompted me to figure out how to do things in Rhino. There are tutorials included in the purchase of Rhino (at least mine had them). Look under the Help menu. I probably spent about a year off and on before I figured out how to do what I needed to. I am no expert by any means...but there are a lot of functions in there that I may never even use.

There is no substitute for just sitting down and playing in Rhino with a specific goal in mind. Unfortunatly as with any software, there isn't a way to magically infuse your brain with how to work in Rhino. So...dedicate a certain amount of time each week to learning and going through the tutorials.

-Brady

[paco]

Yes, I noticed and learned the inclued tutorials... I too figure that many functions I will never need... it's just to figure which... In fact I don't think that I'll be designing highly sofisticated 3D parts... just that I wish the results to be up my mind; not limited by the software...
Thanks! Now lets get deep in!

[Mayo]

In addition to creating toolpaths from 3D files, Meshcam allows you to tranform BMP, JPG, PNG, and TIF image files into a toolpath. You can download a 60 day fully functioning evaluation, and if you decide to purchase, the cost is $100. through November 2004. The software will not create toolpaths for any 2D or 2.5D vectors - only 3D DXF files or stl files. The toolpath options include cut along X, cut along Y, cut along X then Y, and waterline machining with the capability of cutting selected slices. It also has a .sbp post processor.

I've got about 25 days left in my evaluation version - I'll see if I can get a couple pieces cut and pics posted on here.

I'm not connected with Meshcam or receiving any sort of compensation - I just think it's pretty cool software some of us could make use of. Meshcam (http://www.meshcam.com)

[daniel_carr]

You can do it all in ONE software package (VS3D - currently priced at $975). In VS3D you can import the image and control how the brightness is mapped to surface height. Unlike a lot of the other packages, you can perform Virtual Sculpting on the relief surface to fine tune it. For example, in VS3D you could fix the sunken-in eyebrows on that surface that Paco posted.

And VS3D will automatically calculate the 3D tool offsets at each point along the path, based upon the actual 3D shape of the cutting bit. And lastly, VS3D will output the necessary ShopBot Part file (.sbp).

If you want a very detailed surface (one with small intricate fonts, for example) then 200x200 probably will not provide sufficient resolution. I've worked with some as large as 1600x1200. Of course, the amount of processor time and memory usage increases with higher resolution.

[jsfrost]

Obviously, the right software package is nearly always the best answer when profit is required. But when the goal is learning and exploring Shopbot, there are less expensive ways that work. I have had good, but time consuming, sucess lifting sunken eyebrows and the like by adjusting greyscale contrast in Photoshop (expensive, but I own it). Other photo packages will likely do the same.