Modelbuilding

[Danny Bimmel]

Dear all,

I’ve been using DELFTship for quite some years now for my model building hobby. I started drawing the hulls of my models with Free!Ship because the linesplan of the tug I wanted to build was very bad but I also got a list with all coordinates of the hull and didn’t know what to do with it. When searching the internet I found Free!Ship and it really helped me draw the hull with that list of coordinates and later on make a nice model of it. When DELFTship introduced the use of background images I was very pleased because from that moment I could trace the original linesplan of the ships I or some of my friends would like to build. With that drawings I was able to CNC mill the frames (like the pictures below) or even 3D mill complete hulls.

At the moment I’m drawing a hull for some friends of mine and besides the frames we would also like to mill the hull plates fot this model. With DELFTship Free I’m able to unfold the hull plates but unfortunately I’m not able to export this to a DXF-file. Could someone with DELFTship Professional help us out? We only need the DXF-file of the hull plates.

Danny.

Attachments:

• Vos_Shelter_DelftShip_06_k.jpg
• Vos_Shelter_DelftShip_07_k.jpg
• IMG_2651.jpg
• IMG_2662.jpg
• 2013-08-1621.06.08_k.jpg

[Marven]

If you send me the delftship model I’ll have a look at the plates and send you the DXF file.
You can send it to info@delftship.net

[MICHAEL KERR]

That’s fantastic Danny so is the DXF formate standard code for small CNC milling machines or just you machine ???

[Danny Bimmel]

Hi Mike,

That’s right, the CNC machines I know all use vector based drawings and with some modifications the DXF-file which Delftship produces can be used for CNC milling. Even better, you can export a STL-file of the hull and then you could 3D mill a mould for a model :woohoo:

Danny.

Attachments:

• IMG_1710.jpg
• IMG_1713.jpg
• IMG_1716.jpg
• IMG_1723.jpg
• IMG_1724.jpg
• IMG_1729.jpg

[MICHAEL KERR]

That’s for your reply Danny.
That’s brilliant what you have done with the hull mould, have you every tried to do a deck / cockpit / super structure or would that be bushing it too far ???

[Danny Bimmel]

Hi Mike,

I use DelftShip only to draw the hull, for all other parts I use programs like SolidWorks and AutoCAD.

Danny.

[Anneler Ruedi]

Hi Danny

your models look really great !
I’m using Delftship Pro 8.08 to develop a new kind of recreation rowboat. By doing tghis I’ve seen that the exported stations (dxf file) have spline contours. These splines are created as a number of straight (not bent) lines connecting points. So the program I use to convert the dxf into g-code for the cnc mill tells and shows me that there are “staircases” instead of smooth curved lines.

On your photos it seems to me that your cnc mill had smooth lines to mill. Correct?
I’m interested in your process from Delftship dxf Export till the g-code and the milling.

All tips and hints to improve the smoothness of the station border lines are highly appreciated

Attachments:

• 2016-05-31_biber-js1_station-3000.dxf

[Danny Bimmel]

Hi Biber,

I’m using AutoCAD to modify the DXF drawings which DelftShip generates and then VCarve to make the g-code for the milling machine. To minimize the chance of imperfections in the design I always draw the hull in 1:1 scale and then scale it back to the desired scale (normally 1:50). I never encountered problems with “staircases”, maybe I have them also but because the drawing is scaled down it’s not visible :ohmy:.

Danny.

[Anneler Ruedi]

Hi Danny

I undersatnd what you sayy, but as I’m developing a “real size” boat, I cannot scale it down. Could be an option to draw it 50 times bigger than what I want to have in the end, he he …

In the mean time I’ve found out that the type of the lines in the exproted dxf depensd on the version of autocad one selects when exporting e.g. the stations. I’ve been told that the default export creates splines, and that chosing autocad version 13 or 14 does the same. This is correct. The stations in the dxf are symmetric too. Besides both types of lines (polyline and spline) are rather the same – so the polyline and the spline curves are very similar and do show the same contour with very small deviations. The main difference is that the control points of the polyline lie on the “corners” of the straight lines the polyline is created with, but the control points for the splines do not lie on the line itself (this can be checked / seen in a good cad program).

I now export the contours of the stations as splines (autocad V14 option), and they look rather well. The remaining problem ist to connect the four splines I get for a certain station (hull/deck left and right side) to a continous line that is needed for the conversion to g-code. I’ve found out that turboCAD an connect splines, but the result will often be a polyline with a high number of control points. turboCAD does connect splines as splines only if the two arcs where the splines meet form together a proper arc too. As this is not the case with my stations, I always end up with a closed polyline contour. I’ll check this with a cnc milling converter, but think that the precision is good enough for a real size boat. We’ll see …

Attachments:

• 10imported-and-reworked_autocad-v12_2d_dxf-polyline_inturboCAD-as3d-polyline.jpg
• 12imported-and-reworked_autocaddxfdefaultpolyline_andv14spline_inturboCADshow3-dpolyline.jpg
• 20imported-and-reworked_autocad-v14_2d_dxf-spline_inturboCAD-assplinecurve.jpg
• 22imported-and-reworked_autocaddxfdefaultpolyline_andv14spline_inturboCADshowspline.jpg
• 90imported-and-reworked_autocad-v12_2d_dxf-polyline_inturboCAD-asbeziercurve.jpg
• station5750autocadv14dxfimportedsplinessavedas.dxf

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