VIIC 1:45 modell

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thschrader
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Joined: Sat May 20, 2017 12:06 pm
Location: Germany

Re: VIIC 1:45 modell

Post by thschrader »

@the public
the (low) drag-coefficients are calculated for a perfect smooth body.
In reality (especially for the VIIC-body) the cd-values are a little bit higher,
because of body-roughness (ceilings, cannon, flood-openings, body-paint, fouling...)

Edit:
http://www.dtic.mil/dtic/tr/fulltext/u2/a428039.pdf
hds
Posts: 117
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Post by hds »

Because i got several requests for CAD files, here you may download if you like the frames of the outer hull as FreeCAD file.
hds
Posts: 117
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Post by hds »

frames plastification second attempt ...
FramePlastSecnd.jpg
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hds
Posts: 117
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Post by hds »

Status of today. Cleaning and removing of excessive plastic finished. Frames are ready for assembly. In the top right corner pls note the chief of construction ("The Boss").
spanten.jpg
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P.S: Lost my money on E-Shore in trying to get an old 27MHz radio control system ... instead of throwing good money after bad i ordered a 12channel 2.4GHz from outer space in the east. That necessitates an redesign of the antenna routing to the surface. [Sigh]. On the other hand i get a pressureless diving tank for free ....
hds
Posts: 117
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Post by hds »

Summer is over, back to the workshop.
Second aft section assembled.
Added 4mm alu bars as reinforcement (probably overkill, but what the heck).
Changed some details for the rudder section so that assembly will be easier.
In the background the first aft section.
secondAftsection.jpg
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hds
Posts: 117
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Re: VIIC 1:45 modell

Post by hds »

Some progress. Front section quite ready. Next is the body separator between frame 27 and 28. For the PC now some hull section will be designed. May be i could use FreeCad for this to "plane" some of the hull parts. At least the ones with the cutouts.
vorschiff1.jpg
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vorschiff2.jpg
vorschiff2.jpg (413.53 KiB) Viewed 2764 times
hds
Posts: 117
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Post by hds »

Help requested:

I want to "unroll" the lofts with the cutout of the hull. Attached pls find a test file. What shall be achieved is that the loft with the cutout is exported to DXF for further machining .i.e. laser cut. I'am struggling with the macro "unrollRuledSurfaces". It does basically what i want, but does not create the cutout. Could it be possible to extend the macro for this szenario ?
LoftTest.jpg
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VIIC_Loft_Unroll_test.fcstd
(36.14 KiB) Downloaded 82 times
hds
Posts: 117
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Post by hds »

Ready for the hull and the technical stuff.
viicKeel.jpg
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hds
Posts: 117
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Post by hds »

Hull on the aft section as test. 4 layers of nylon + epoxy resin. To smooth the sharp edges a layer of paper has been applied. It seems that no additional support layer is needed. Only for concave contours as at the bottom and the diving tanks a special preparation step has to taken first to stick the nylon to that form. It might be that 4 layers are too much but lets see tomorrow.
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hds
Posts: 117
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Post by hds »

The day after. Looks not too bad for the hull. But as mentioned some prep work needs to be done for the cutouts and concave shapes.
IMG_20181104_150848.jpg
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Just a quick show off how it looks like with one layer. For the impatient ones (well me ....). The project will be delayed because i face a surgery on tuesday. Till then. Have fun.
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