The spline function in AutoCad is fine, but some manual judgement is needed at the ends of the spline. AutoCad wants to be told the direction of approach to the very end points of the spline. Here are 4 splines drawn through the same points:

Chad,

I used the MechMate logo design from one of the DXF files and blew them up to 9 and 6cm high.

Ries

You are right Gerald. I remember that one can adjust the parameters of the spline line. I am trying to find it in the program at the moment but.. where is it. Not sure if that wil work and give the right line in the end?

Hi Lex , thanks for the offer but I've got to do it myself . Otherwise you will have to do all my designs . I was also looking for a cheap CAD package to do it in . I've been using a demo version of Rino3d but dont want to pay that much for it .

Chad try Deltacad cheap and easy

thanks hennie will try it out today .

Hi reidcd

What do you want to do with the curves that pass through the 11 points that you have? what's that for? stringer? I can give you some help if it is... Using autoCAD works, but not the best option.
francis

Hi Francis , yes its for stringers . So far the best curves have come from Rhino3d . What option do you suggest ?

www.boardcad.org

let me know how you go.

What you want to do is... design your board and export the profile as dxf polyline.

Also you can use your 11 points coordinates. Just put the coordinates in the guide points box... and then manually pull the curves through them, it's much better than using autocad or whathaveyou.

francis

Chad

As francis says boardcad is pretty good for what your are doing. Only additional comment is that if this is all you want to do then just use the webstart version, the full version with CNC can require a little perseverance to get up and running (it also has a few bugs in the code generation).

Chad - A shaping machine, now your talking.

As Jed says boardcad is good for design and free. I personally have had issues generating gcode, probably just me though. I normally design in AKU shaper and get them cut on CNC machines on the Gold Coast in Australia. I am still investigating what path to follow and have dropped the ball while the actual build is underway.

I know there are some tricks of the trade with respect to the shaping applications to gcode. Some of the solutions also take some serious learning time, if you have not already done so you might make some connections on www.swaylocks.com on their forum.

Cheers
Ross

Chad

If you actually want to shape with your machine then Boardcad is still an option, particularly if you have a seperate CAM package (say Rhino CAM) there is functionality in the webstart version to export your designs as STL's which will work fine in most CAM packages, this should give you better controll than what I have seen from BoardCAD so far which has a couple of issues in the toolpaths particularly around the rails. But for stringers the export profile to dxf works a treat (I've been experimenting with this for creating frames for a hollow wooden board).

Your the man Jed - spreading shaping joy to us wannabe foam mowers. Never thought of passing off the CAM to another application so thanks for giving us both the tip.

Ross

@ Chad

Try http://moi3d.com

The developer use to work for McNeel on Rhino

30 day trial and a very reasonable price

D

Yeah, boardcad is not ready for toolpaths yet. Another year or so it will probably take for it to be reliable. we'll see...

f.

I've used boardcad but have a problem when Importing the dxf into sheetcam . Looses its shape ! reports an error !

I design all my boards in Surfcad . This is the original shaping package that boardcad , shape3d and Akubird have all copied .

Chad

Attached is gcode for the stringer of one of my test board designs, open it up and let me know what you think, if it looks like what you are after then perhaps the cnc version of BoardCAD can solve your problem. If this is the case then try setting up the full cnc version of boardcad, if you have issues then pm me and I'll do my best to help. Other way this could be done is by dumping the stl from boardcad and then create a slice in your CAD/CAM package.

Jed

thanks Dickie I'll try that Moi3d . I really like working in Rhino3d so if Moi is similar I'm sure I'll love it .

forgot to say this... you have to scale the .dxf exports from boardcad. Do a scale command with a factor of 1000, be it in rhino, autocad, cut2d... suppose you will want to nest the stringers.

Surfcad was one of the first programs and it works well, but the control you have over the curves is quite difficult if compared to boardcad.

no worries.

Hi Francis , I scaled up the dxf in Rhino . All looked good . But when I open the DXF in sheetcam the rocker is very angular !

Hi Jed . Opened the Gcode in Mach3 . Was it just the bottom curve you sent ? I've cut a few stringers now using the files I created in Rhino . They are very close . Just need to tweek them in two places by 1/16"

I have worked with the developers to try and get the .dxf export up to the standard of autodesk. That is quite weird though. Perhaps the version you are using is pre-last update on the .dxf writer. Can you attach the 'problematic' .dxf for me to have a look? I can tell straight away if it is up to date. Then I'll try to open it with cut2d.

cheers,
f.

Chad

meant to send full profile but looks like I sent the wrong file. If you have the dxf working this is almost certainly a better way to go so I'd stick with that as it's much more flexible.

Jed

Downloaded Boardcad again and did a profile for a 6'6" . this one worked fine :) I've got both methods working . see attached DXF

nicely done. This .dxf is up to date.

Edit: Better introduce myself, rather than simply dropping in. I'm a kneeboard designer based in Melbourne Australia (originally from Durban, SA). Been cutting boards on commercial machines for a few years. Avoiding the surf machines after pretty poor results. Now getting a machine together for my "hobby" (as my wife calls it).

About the thread:
Congratulations on getting the machine together and running (and pretty quickly, too, even with the delays).

End Edit

Interesting stuff on the software, since I'm currently debating what software route to go. The industry standard for cutting is Shape3d, but it's a bit costly. I had considered getting the export version of S3d to convert to dxf, whence to CAM software (I've done this in the past and it workd well).

From what you're saying I could save myself a few thousand Euros using a combo of Boardcad and a cam software such as MoI? Are there hidden pitfalls I should be aware of?

Hi Red
 

Hi Red , you and Gigs must be the only kneeboarders left . I dont use the Mechmate to cut surfboards . I cut stringers with it . I personally dont like shape3d . I love surfcad because I get what I want out of it . Maybe look at the boardcad CNC option . Looks good .