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FeiJi's blog
Archive for June, 2012
Posted by FeiJi | Jun 11, 2012 @ 05:05 AM | 3,738 Views
Lately I have been building wings with 9mm EPP foam and decided to test the weight bearing ability of laminated EPP. I bought the laminate from a copy shop but had to measure it with a micrometer to determine size.
Here are the results of my test with photos. The weights are approximate as my scale is not digital. I just kept adding double a batteries until the foam/laminate collapsed.
Single lamination was a single layer on all surfaces. Double was two layers.

10cm * 50cm 9mm EPP Weight Bearing Test

Laminate Used..................Weight of Foam with Laminate.....Weight Until Collapse
none...................................12 grams.......................................70 grams
single .045mm laminate.....25 grams.......................................340 grams
double .045mm laminate....35 grams.......................................660 grams
single .095mm laminate.....30 grams........................................950 grams

Looks like the single layer of .095 laminate is considerably stronger, even than the double layer of .045.

Laminated EPP foam is really strong stuff. I am finding that wings made of laminated epp last much longer than ones made of foam board. The foam board wings get soft and mushy after a while and then never fly consistently. The epp wings always stay stiff, the components don't move and they fly the same way everytime.
Posted by FeiJi | Jun 06, 2012 @ 06:17 PM | 3,296 Views
I am on a finless flying kick and this video is of some first flights (not too exciting) to see how things go. I like it. No more broken fins and it still handles great.

BoneYard 2 Finless Foam WIng (2 min 37 sec)


Also included picture of Venus transit from this side of the world. Taken with exposed color film held in front of my camera lens set on manual and zoomed to 10x.