Transferring plans to CAD

[Glenn Patterson]

I used ACAD to draw the parts patterns accurately then we glued the patterns to the metal with 3M 77 Glue. The patterns simplified making all the bits and pieces. The Lee Valley optical center punch spead up setting the punch marks for accurate drilling of the parts. The paper washed off easy with a laquer thinner or with naptha. The sum of the parts will build the Bearhawk and for the rest the Barrows drawings were adequate.I put grids on the paper drawings to get scale and then put the same grid in full size on plywood to make the tail feather jigs. Left & right Horizontal tail were made from the same jig. Combination of old school drafting techniques and technology. Not sure putting the whole airplane in CAD is worthwhile as using the time to make the pieces will get one there quicker. We had one builder visit the shop during our construction who was explaining in lengths the depths he was going to for his construction. We could tell he was lost and mired in the process of the process rather than being efficient, He flamed out shortly after. Best is keeping all the processes simple as possible to get a quality build and keep moving forward. A person only has one life so tackling the project head on and fabricating is daunting a process for a scratch builder. Be careful with the hours spent as hours lost in CAD could have been a lot of parts made with the project advanced further than having hours and days in a virtual creation.

[triumphantduke]

yes, I think you are very right (wrt to flame out and 3d not being required/useful)- I'd like to be cautious against efforts that would cause me to flame out. For me personally it is more so if I'm unable to work towards building or find myself with "free" time waiting on something. The main reason to is to practice and develop skills for managing an aircraft throughout its lifecycle within the software I professionally work with. I have a job today, but according to my calculations I need to ensure I keep the job to finish the bearhawk. I'm aware of the shortfalls that can and do occur when a design engineered and produced through drawings is converted to model form. I was curious if any official model progress has occurred, because that saves me time. There's much more than model conversion that I can practice with in the PLM software.

main point, building comes 'first' :) (after house chores, wife, work, kids, etc. etc.)

[Glenn Patterson]

I have managed projects and large maintenance events. It takes serious dedication and there are often days where I would rather have been somewhere else. At work productivity was measured basically as tool time and tool time gets as expensive as one wants. Hundreds of dollars in huge maintenance turn arounds per hour of wrench time. Usually anything over 65% productivity of the tradesman is good. All the hours spent going in tangents that is not producing parts or spent advancing the project physically is diluting the productivity percentage to extend the project timeline. This is not intended to be critical of anyone's initiative but to show the value of concentrated construction time. CAD is an excellent way to make paper patterns of parts so they can be cut out quickly and holes accurately located. Drawing the parts in CAD for patterns can add to efficiency. Our engineering printer was dialed in but they can be printed at home. Put reference marks at 1" spacing and one can adjust the printer scale percent to get accurate patterns at home.

[lutinplunder]

Current state of my CAD work, for those of you not on the Facebook group

[Nev]

Very nice indeed !

[Sir Newton]

Interesting flap ;-)

[way_up_north]

I’ve had a lot of success with the tried and true methods of pencil and paper

since we only have a license to build one plane per plans

For the kids reading this… you’ll be much farther along just getting started building with the traditional methods

[Sir Newton]

I agree, talk is cheap! However I get it everyone dreams :-)

[TLyon]

Cool stuff! I like the drawing process - either paper or CAD as think time. Curious to know what you think about this during/after the build.

[lutinplunder]

Just another update on my progress. Figuring out the spars/ribs/hinges for the flaps, wing skins and playing around with the idea of solar panels at the tips and the center of the skylight.

[way_up_north]

I`ve not read all the posts in here..maybe I missed it...but your flap hinges look like they are beefed up from the originals

never gets old...looking at the Bearhawk design its a great looking plane

[sacherjj]

How much of the solar is Scrapy influenced? :)

I would think the weight in more LiFePO4 battery that charges off the alternator would be a better overall use of weight, unless you have much more solar than that. Unless you see a use case with multiple days in sunlight. Although I like the location choices.