CAD Designer wanted for Jurca Mustang !

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wiloows5050

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I wonder at what point that becomes a problem. If someone made CAD files to CNC cut components for a popular plans built airplane that would be good for all, no? It would of course be a bad idea to totally redraw and sell the entire plan set to replace the originals.
I think the way most people would do is supply parts that were made from a licensed drawing using the cad. Not necessarily doing everything I.e. precut wing ribs or fuselage formers. It would be so much easier if Patrick from Jurca would chime in on this discussion. He’s a member here. His take would provide valuable guidance as to what Jurca wants.

This guy seems like he wants everything pre-made for him or drawn for him so he doesn’t have to make the parts himself.
 

proppastie

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So not, you dont need a 3d lazer scanned images
sorry for the misunderstanding.....the 3D model of the airplane is in the computer.....the lofting is done exactly in the computer in much the same way it would be done with a full size master model or a one off build.......the output would be pen-plotted mylar contours for making the shapes or CNC cut ribs or bulkheads ..... we made airplanes long before we had computers so yes it is not necessary......the problems come in when someone thinks they can CNC cut ribs and frames and the kit will snap together.....that will not be the case with hand drawn paper plans.
 

Tiger Tim

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This guy seems like he wants everything pre-made for him or drawn for him so he doesn’t have to make the parts himself.
Oh yeah, that ain’t going to work. I feel like an airplane reduced to an IKEA-style kit would take several iterations of every part before it would ever work.

These threads (and there have been a few) are wild. I wouldn’t have the guts to say, “I want a scale P-51… but I don’t want to pay for it… also I’m not willing to do any work or even learn anything,” even once, let alone however many times it’s been posted.

I’ll tell ya if it works I’ll be changing my tune. Expect to see the above but sub in ‘full scale’ and ‘Mystery Ship’ 😂
 

proppastie

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When designing bending punch press dies I was able to hold +-.005 in dimensions .....the same with precision tooling in the Amada bending break. +-.005 was a standard tolerance. with my cheap junk Chinese bending brake I am able to hold +-.010 in dimension.......my pen plotter will plot to +-.010 or better....hard to measure because the pen width is more than that.
 

Riggerrob

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The one word I haven't seen yet is "checker".
Yes. Quality control is a big issue.
This reminds me of an interview (Wooden Boat magazine a couple of years back) with the head of Chesapeake Light Craft, a leading manufacturer of plywood kayak kits.
When the interviewer asked about e-mailing out CNC cut files ... to be cut a the local CNC shop - the head of CLC replied NO. He was afraid of intellectual property theft and quality control problems. Who can predict if the local CNC shop will insert the correct grade of (boat quality) plywood.
CLC also worry about being sued after a drowning involving a sloppily-built boat made from third-generation, pirated copies of their design. Even if CLC can prove that the boat was built from out-dated, inaccurate plans and CLC was not involved, lawyers can still bankrupt an innocent company.
 
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geraldmorrissey

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"Checker" has nothing to do with mics or guage blocks. A design group checker examines new and revised CAD files for accuracy, compliance with company modeling standards, compliance with company drafting standards if drawings are part of the CAD package. Plus, and most importantly, does the design satisfy the reqirements for fit, function, and manufacturability. That's why there is a signature block on dwgs. It's a job usually done by the more experienced designers. Stress, weights and the shop usually have to sign off as well. It can also be boring as the dickins. I did it for years but never much cared for it. It's a dream gig for those that enjoy tedium. I've worked with great checkers that were not particularly great designers. These days everybody with a laptop is a CAD designer. I'm building a Bearhawk, nearly every new plans holder wants to mock up the plane in CAD before they build the first detail part. Plus they want to share these files with all the other builders. Just my opinion, NEVER accept CAD files from anyone except the designer. You never know what your going to get.
 
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Dan Thomas

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Sep 17, 2008
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These days everybody with a laptop is a CAD designer. I'm building a Bearhawk, nearly every new plans holder wants to mock up the plane in CAD before they build the first detail part.
We have become obsessed and completely reliant on electronic wizardry. It's not healthy. It dumbs us down. A recent article on the GPS navigation systems in cars says that drivers have lost the skills of mapreading and interpretation. The skills of determining spatial location and direction. It gets drivers into serious trouble sometimes. They blindly follow the GPS even though the road is obviously the wrong road.
Lorraine Explains: Could GPS be compromising our brains?

Paper plans require you to think. They require you to get out the protractor and engineer's scale rulers and use them. They require you to add up a series of measurements along a spar, say, and see that they add up to the overall length on the plans.

Exercise your brains. You need them when you fly, and if they get lazy you're going to be in trouble sooner or later.
 

Monty

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an amature designer usually does not have such help.....probably should though.
Does it fit together is my checker....seriously though, the sloppiness in everything open source is appalling. I cringe when I see github or grabcad. As highlighted, having the cad files is only half the battle. Just because you have drawings doesn't mean you can produce a part to spec. Asking for free professional results....is a waste of time. Maybe as a one off favor for a friend...otherwise no. The fee is also effective in keeping non-serious people from wasting my time.
 
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