5 posts in this topic
As I mentioned in another thread, I have a heap of material left over from building 1830 F-arc's. The f-arcs are made from good quality chikara ripstop and it is too good to just throw out, so I decided I needed to put it to good use.
I have been playing with Surf Plan for a while now and although I can get a design that looks good, I have no idea if the design will fly or not. Then one day looking threw some old archived websites, I found a link to the surf plan design specs for a 6m p-arc. P-arc (P=parallel) was the original name of the F-arc, but was changed before release because Parc backwards is crap
anyway, I decided it was worth giving it a go since I already had the material. So I got the plans printed out on A0 paper and set to work.
first thing I had to do was unpick every seam on the remaining sections of 16m f-arc, which took a lot longer then expected.
next came the marking out and cutting. Because I was working with material that had been folded and crushed, rather then off the roll, it was a nightmare getting it to lay flat to trace the outline on to. I had to flatten an then clamp the corners to the table. As well as the outline of each piece surfplan also allows you to add waypoints so everything can be aligned after being cut.
I used a hot knife to cut all the pieces out to make it a bit quicker and stop the edges from fraying.
i then used double sided tape to stick all the pieces of the top and bottom skin together for sewing. The ribs were too difficult to stick in place, so they were just aligned and stitched as I went. (A walking foot attachment from eBay makes sewing ripstop sooo much easier)
The surfplan design didn't have spar pockets, so I made them from some 50mm webbing and stitched them to the end cells.
I also added internal front and rear straps of 25mm webbing, similar to the more modern arcs. Like the modern arcs, the rear strap has adjustment for the middle 5 cells and wingtip 5 cells. I also made the front line adjustable at the middle 5 cells, in case the kite was prone to backstall.
And the finished product.....
flat area: 6m
wing span: 6m
I estimate it took about 100hrs, cost $150 and countless 🍺