Alibre and GTCO Calcomp Digitizer pad

[blamb11]

I did a search and anything I found was from way back in 2007 and such. I have a customer that I write programs for and they need flat parts digitized into a DXF file so I can draw them in Alibre and create my g-code files. Doing some looking about I find GTCO Calcomp Digitizer pads, you lay your flat part, print or pattern on the tablet, trace it and it is supposed to input the points into your software. Will Alibre take this type of input, do I need an intermediate software to create the Dxf first, or how would I go about this?

Any help would be appreciated...

Thanks,
Brian

 

[HaroldL]

Brian, I take it that there are no drawings for these parts?
If memory serves me correctly, GTCO Calcomp digitizer were mostly used for AutoCAD. I have a couple of digitizers, one GTCO and one Kurta, that I used back when I was using AutoCAD 12 to 2000. I doubt they would work with Alibre since they are 2D input devices.

You would most likely need to create a DXF first then import that into Alibre. Try checking with the Logic Group, it looks like that's what they do or sell equipment that does.

 

[Lew_Merrick]

Brian -- I may well be misunderstanding, but it soulds (to me) as if your customer has 2D Flat Parts that need to be measured in order to generate geometry that cand be used to generate 2-1/2D CNC G-Code. Is that correct? What is the longest dimension of said part set?

 

[blamb11]

Parts have no drawings, custom motorcycle stuff, all free form and organic shapes. The Logic Trace stuff is what I have seen also and I have a call into GTCO Calcomp (they are local to me) to see what sort of software and compatibility issues there are. Parts can get a bit large, currently some that are in the range of 28-30".

I really don't want to have use a CMM or some such to measure the parts and was looking for something quick and dirty to create the DXF files. I can use 1/4" graph paper and hand measure if I have to, but that seems pretty archaic...

 

[HaroldL]

all free form and organic shapes.

Are the parts flat? Have you thought of using a 3D scanner and importing the point cloud?
Sounds like it is not going to be quick but it will be dirty.

 

[blamb11]

Sorry, yes, the parts are flat, just free form curves, nothing is straight or parallel to anything else. We don't need 3D, this is just taking a handmade template that they have dialed to fit, and then be able to get it to g-code so they can run production and a flat bed router.

Typical type of part...

TL1 V2

• blamb11
• Apr 2, 2018

 

[jfleming]

On the side, I make graphics kits for ATV's, Motorcycles, and SXS's. I trace out templates to fit the plastics and take them to staples where they scan them in. The local one can do 36" wide X unlimited length. This has proven to be very accurate for me. Perhaps this would work for your application?

 

[blamb11]

Thanks J,

That might be an option, customer has no problem spending some money on a method to streamline his process, so I'm just trying to find something that will be easy for them to manage. Parts were previously made using a pin router and templates, he now has a 4'x4' CNC router and wants to automate the process. His templates or what he makes as a pattern are rigid though, maybe 1/4" or 3/8" ply or MDF, so will this scanner handle rigid parts? Flatbed scanner of monstrous size? Or meant to handle paper and it just feeds it through rollers or something?

I managed converting one of the parts by creating a TIFF picture file, opening it in Alibre and drawing/tracing over it, but that get's a bit tedious with something 28" long and no curve is consistent enough to be more than an inch or so long. Watching the videos of the Logic Trace digitizers, it looked like a fairly fast and easy method of converting templates into DXF files.

 

[KMoffett]

I do this too. I shoot the part from a distance with a telephoto lens. This reduces parallax if there is thickness. I place a scale next to the part, so when I import the part into Albre I can scale it to the correct size. Continuous curves are a pain. But if you need it....

Ken

 

[VoltsAndBolts]

I do this too. I shoot the past from a distance with a telephoto lens. This reduces parallax if there is thickness. I place a scale next to the part, so when I import the part into Albre I can scale it to the correct size. Continuous curves are a pain. But if you need it....

Ken

I have used a similar method. But take the photo into inkScape and convert it into a DXF. Then I scale it if need be in 2d CAD, convert to gcode and cut on my CNC Router.

 

[blamb11]

I can do the photo, import into Corel Draw, outline trace, convert to DXF and then import into alibre, or go straight to CAM if I don't need any layers.... but... asking the bike shop to accomplish this might let the smoke out of their skulls... if you know what I mean.

I would like to find something that's direct into CAD, then the output to CAM is easy and simplify the process into a couple of steps. I talked at length to the Calcomp people today, and the unit is basically a tablet or mouse type of thing, has a windows driver to install. They are the hardware folks and talking software kind of went over their heads, but they know the unit does work with Autocad and Solid works, so one would assume (dangerous, I know) that if I had the digitizer hooked to the computer (it's just a USB device) and say I select straight line and using the pen select two points, I would expect a straight line, same with curves, use beginning, end and arc and click three times and I should get an arc....

All this sounds great, but do I take the risk and buy a used one and test it out....

 

[Dave H]

Can you actually trace their templates/parts onto a large piece of paper then take it to Staples to be scanned to DXF? Then generate your G-code.

 

[blamb11]

That is a possibility, will have to try it out and see what sort of results we get.

 

[NateLiquidGravity]

Based on my past use of a different brand of digitizer tablet with AutoCAD I don't think the digitizer tablet will work with Alibre directly. In AutoCAD I had to turn on the digitizer tablet and then calibrate it to output true size dimensions. AFAIK Alibre Design doesn't have this ability.

To be honest - since you don't need 3d I wouldn't even use Alibre Design.

 

[oldfox]

I have used a similar method. But take the photo into inkScape and convert it into a DXF. Then I scale it if need be in 2d CAD, convert to gcode and cut on my CNC Router.

I have used this exact procedure. The only glitch I found was that it produced a "double" sketch in AD. Double as in one true figure and a false figure either inside or outside of the true figure. Did you have this problem? If so, what fixed it?

 

[VoltsAndBolts]

I have used this exact procedure. The only glitch I found was that it produced a "double" sketch in AD. Double as in one true figure and a false figure either inside or outside of the true figure. Did you have this problem? If so, what fixed it?

I haven't seen the double thing...

One application I did this on. https://www.alibreforum.com/forum/i...dimensions-from-photo-file.19139/#post-119390

More detail.

I take the photo on a solid white background if possible with an item of known size in it for scale.

I convert the photo to Black and white and use inkscape’s bitmap auto tracing to create a SVG (Scalable Vector Graphic) file.

I then convert the SVG to a DXF.

Open the DXF in “DraftSight” Cleanup the DXF and scale as needed. Save and open in Victric Cut2D and make gcode.

Cut the part.

Note all the software needed to do this if free except for Cut2D.

I highly recommend inkscape, it's a great tool to have in your tool box.

 

[bigseb]

I use Inkscape a lot. Not for work stuff though...

 

[jfleming]

I too have done the photo thing in the past, for these paper templates though, the Staples scanning method has been more accurate. I wish there was just a pen-like tool that you could just trace something out and it convert it to a path somehow. Wouldn't that be slick?

 

[blamb11]

There is a pen tool, you use it with the Calcomp digitizer that I started this whole topic about... here is a video of one process, this is using a multiple button mouse:

and this one is using the pen: