{"id":4106,"date":"2020-09-26T00:40:33","date_gmt":"2020-09-26T05:40:33","guid":{"rendered":"http:\/\/www.balsaworkbench.com\/?page_id=4106"},"modified":"2020-10-26T11:37:50","modified_gmt":"2020-10-26T16:37:50","slug":"chuck-cunningham-foam-floats-part-3","status":"publish","type":"page","link":"http:\/\/www.balsaworkbench.com\/?page_id=4106","title":{"rendered":"Chuck Cunningham floats part 3"},"content":{"rendered":"

Hey, I wonder if Chuck Cunningham’s foam floats can be made without foam. \u00a0Let’s find out.<\/p>\n

I’m building a Bingo 20 to fly from a friend’s pond. \u00a0I was going to build these from foam just like the 36 inch set, but at the last minute I decided to use just wood instead.<\/p>\n

The main difference between wood floats and foam floats is that if you make a bad landing with wood floats, depending on how hard you smack the water, you can split a seam and the float will take on water, and then your plane will sink. \u00a0Foam floats\u00a0can’t fill with water because they’re already full of foam. \u00a0But I \u00a0don’t plan to have any bad landings, and I’m sure you don’t either, so I’m going to go ahead and make some Cunningham-style foamless floats for my small Bingo.<\/p>\n

According to Chuck’s formula<\/a> the floats should be about 27 inches long. \u00a0I calculated the outline of the float side and cut it from 1\/16″ balsa sheet, and I cut the plywood spine as well. \u00a0When I decided to make the floats from wood I cut out bulkheads from lite ply. \u00a0I figured there was room in there for about 7 bulkheads including the front and back. \u00a0Because I won’t have foam to hold everything together\u00a0I decided to put 1\/8 x 1\/4 balsa stringers on the top and bottom edge of each float for a little bit of extra strength.<\/p>\n

\"DSC_1311\"<\/a><\/p>\n

From there it was pretty easy to stick the two sides together with the bulkheads in between.<\/p>\n

\"DSC_1312\"<\/a><\/p>\n

\"DSC_1313\"<\/a><\/p>\n

I have the spine set in place in this photo, but it’s not glued yet. \u00a0First I made a single top plate from the hard spine, plus a strip\u00a0of\u00a03\/32 balsa\u00a0on each side of the spine.<\/p>\n

\"DSC_1314\"<\/a><\/p>\n

\"DSC_1315\"<\/a><\/p>\n

The top plate is placed on a flat surface, and the float is glued to it.<\/p>\n

\"DSC_1316\"<\/a><\/p>\n

I’ve decided to cover the aft section with 3\/32 balsa sheet, and the forward section with thin birch plywood. \u00a0In all three segments the grain will run crosswise. \u00a0The curved segment at the front will be 1\/32\u00a0plywood, and the main straight segment will be 1\/16 plywood, which should handle landing stress a bit better than balsa, especially if I hit a floating stick during a high speed takeoff run.<\/p>\n

I made a piece of 3\/32 balsa sheet long enough to cover the entire tail section.<\/p>\n

\"DSC_1318\"<\/a><\/p>\n

While holding the float down on a flat surface, I glued this piece in place with medium CA.<\/p>\n

Because two pieces of birch plywood will make a joint where the bottom of the float changes from flat to curved, I decided to add 1\/4 inch triangle stock to both sides of the bulkhead at that location.<\/p>\n

\"DSC_1317\"<\/a><\/p>\n

Once again, while holding the float down firmly on a flat surface I added the 1\/16 inch plywood plate to the flat segment, then the 1\/32 inch plywood to\u00a0the curved segment. \u00a0There was a very small gap where the two pieces of plywood meet. \u00a0I sanded the joint to fill the gap with sanding dust.<\/p>\n

\"DSC_1319\"<\/a><\/p>\n

Then I hardened the dust in the gap with thin CA.<\/p>\n

\"DSC_1320\"<\/a><\/p>\n

With triangle stock on the inside and a filled gap on the outside, this joint is never going to break.<\/p>\n

That certainly was easy. \u00a0It looks like everything is done except final sanding and paint\/covering\/finishing. \u00a0It looks like a Chuck Cunningham float, but this one is a foamless float. \u00a0I like building with wood, so I think I prefer this version, but if you like foam, try it the other way. \u00a0Either way is good.<\/p>\n

All that’s left now is to apply a waterproof finish<\/a>.<\/p>\n

\"DSC_1321\"<\/a><\/p>\n

\"DSC_1322\"<\/a><\/p>\n

\"DSC_1323\"<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Hey, I wonder if Chuck Cunningham’s foam floats can be made without foam. \u00a0Let’s find out. I’m building a Bingo 20 to fly from a friend’s pond. \u00a0I was going to build these from foam just like the 36 inch … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":4143,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"http:\/\/www.balsaworkbench.com\/index.php?rest_route=\/wp\/v2\/pages\/4106"}],"collection":[{"href":"http:\/\/www.balsaworkbench.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/www.balsaworkbench.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/www.balsaworkbench.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.balsaworkbench.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4106"}],"version-history":[{"count":11,"href":"http:\/\/www.balsaworkbench.com\/index.php?rest_route=\/wp\/v2\/pages\/4106\/revisions"}],"predecessor-version":[{"id":4239,"href":"http:\/\/www.balsaworkbench.com\/index.php?rest_route=\/wp\/v2\/pages\/4106\/revisions\/4239"}],"up":[{"embeddable":true,"href":"http:\/\/www.balsaworkbench.com\/index.php?rest_route=\/wp\/v2\/pages\/4143"}],"wp:attachment":[{"href":"http:\/\/www.balsaworkbench.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4106"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}