VIIC 1:45 modell

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thschrader
Posts: 1197
Joined: Sat May 20, 2017 12:06 pm
Location: Germany

Re: VIIC 1:45 modell

Postby thschrader » Mon Jun 18, 2018 6:56 am

@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: 59
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Postby hds » Wed Jun 27, 2018 6:23 am

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: 59
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Postby hds » Sat Jul 07, 2018 2:04 pm

frames plastification second attempt ...
FramePlastSecnd.jpg
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hds
Posts: 59
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Postby hds » Sat Jul 21, 2018 4:41 pm

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: 59
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Postby hds » Sat Sep 29, 2018 3:55 pm

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: 59
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Postby hds » Sat Oct 20, 2018 4:45 pm

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
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hds
Posts: 59
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Postby hds » Mon Oct 22, 2018 6:07 pm

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
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hds
Posts: 59
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Postby hds » Fri Nov 02, 2018 5:04 pm

Ready for the hull and the technical stuff.
viicKeel.jpg
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hds
Posts: 59
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Postby hds » Sat Nov 03, 2018 3:54 pm

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: 59
Joined: Tue Feb 14, 2017 8:23 am

Re: VIIC 1:45 modell

Postby hds » Sun Nov 04, 2018 2:52 pm

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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