chistech

I picked up a 70's era set of Balsa USA 45" floats off of eBay to put together for my H9 Super Cub. I got them for little money because all the die cut bulk heads were missing. I ended up drawing the bulkheads from measurements off the plans the best I could and with the help of my friend put the drawn templates to wood and cut them out. I decided to use H9 float hardware so I knew there was going be some enginnering to get it all to work. I had spoken to Balsa USA about these floats and he told me they were pretty old and when I got them done to send a picture to them because they are so old. I decided to take some pictures and post here a little build thread of these old floats. 1st picture is of a couple of the bulkhead templates I drew up and the 2nd and 3rd are pictures of the bulkheads and stringers done up.

chistech

Because of the H9 hardware I have to make special pockets to recieve the strut ends. We came up with a ply box with a ply end shaped to the airfoil of the strut to keep it from turning in the pocket. I then used the measurements from the step of the H9 1/4 floats to the strut to figure out the placement of the pockets on my floats. The front strut pocket ended up right in the middle of the #4 bulkhead which is ply. I cut out the ply enough to except the pocket, located the position of the rear pocket, and cut out the upper and side stringer. The rear pocket ends up between two balsa bulkhead so I made some web bulkheads to connect the load of the pocket directly to the bottom of the float. 1st picture shows the pockets made with the T-nuts for the 8-32 SS strut mounting screws. 2nd picture shows the #4 ply bulkhead cutout to accept the front strut pocket. 3rd picture shows the front strut pocket in place in bulkhead 4. 4th picture show the rear strut pocket with the ply web from the pocket to the bottom keel.

chistech

Decided to make an additional ply web rib to help support the rear strut pocket. I also decided to put in the servos for the water rudders. Just used a 1/8 ply shelf and slotted the bulkheads on either side. I have made hatch frames for the servo access and will install next. I am kind of engineering things from the inside out. Will glue everthing together with the struts in place so everything can be kept in alignment. The first two pictures are of the rear strut pocket and the two ply web ribs. The 3rd and 4th are of the servo installation.

42etus

My Feedback: (2)

Keep 'em coming. This is a very interesting build.
Paul

chistech

Here are some more pictures of the pocket details. These show the pockets after the ply doubler for the T-nuts has been glued in place. After checking the initial placement of pockets I found I was off 1/4" and had to move the rear pocket back. That is why you can see a 1/4" sq. glued along side the pocket. The distance of the H9 struts from the leading edge of the front strut to the trailing edge of the rear strut is 18 3/8". You can also see in the picture of the front pocket where I had to cut out more of bulkhead #4 to clear the ply pocket doubler w/T-nuts. Again, I will not be gluing the pockets to the float body until I can assemble both floats together to make sure they are straight and true to each other. I have done all my measuring for the mounting holes for the struts off the center spar of the float. By doing this, the floats should come out pararrell. The hole spacing on the H9 struts is the same so if all goes right it should be right. Will follow up with more pics as I go. Had very warm weather yesterday and today and all our snow went. That means our field is ready to fly on and I have a brand new plane to go up. I'm getting itchy.

chistech

We got some more work done. Finished installing the pockets. Planed and sanded down the pocket ends to match the angle of the float sides. Routed out small oval sections of the balsa top deck and replaced with 1/8th ply biscuits to prevent the balsa from crushing when the bolts are tightend. Cut out servo access holes, made ply underframes to have something to screw into, and made ply hatch covers. Ran Nyrod pushrods for the H9 rudders. Both pushrods needed to be crossed over the centerline of the float because there is a left and right rudder with the tiller arms to the inside of the floats. I have set up the rudders to work with the same direction of my H9 Super Cub's rudder if I was to put the rudders on a Y harness with the plane. I can also of course couple with another channel. 1st picture shows the rear pocket planed, sanded, and the ply biscuit installed. 2nd picture shows the rear biscuit drilled for the 8/32 mounting bolts. 3rd picture shows the completed float with both pocket ends shaped, biscuits installed, drilled, pushrods for rudders installed, ply servo hatches installed, ready for siding. 4th picture shows the Nyrod pushrod installed showing the cross over the centerline by the rear strut pocket. 5th picture shows the rear of the float with the smooth transition of the pushrod out to the rear bulkhead. These old floats are somewhat smaller at the rear of the float than the newer floats available today so there was very little room for the T-nuts to mount the rudders to. The T-nuts just fit between the upper center stringer and the keel. My buddie is going to start siding the floats with pieces of 1/8 balsa set with the grain on the vertical. I will post pictures of his progress. We will also be making custom ballast containers at the front of these floats so weight can be added or removed for ballast.

chistech

My buddie got one float sided and started to sand and round the top deck corners. I cut out the oval holes in the balsa for the struts and test fit them. This old kit has some real nice quality balsa in it and some of the siding pieces are as hard and dense as basswood. We are using those pieces close to the step area for strength and that they stay pretty straight with no real need to bend because the float is pretty straight in this area. Will do the other float then start on the bottom planking. We also went down to our field today and got in one flight with my trusty old Spitfire. It got too windy with a westerly crosswind so we packed up after just one but still got to fly.

chistech

Here are the custom ballast containers. They're not complete yet. Haven't made the covers. These are made of 3/4 copper pipe. The cross piece is 3/16 mild round steel, flat ground in the center, drilled and tapped for 4-40. I bore the holes in the copper just a little undersize and chucked the round rod in my battery drill. I spin it fairly slow and let it work it's way through the hole and into the other side. I center the hole, make sure the threads are 90 degrees to the pipe, then cut off flush with the pipe and grind. We will be drilling 7/8'ths holes in the solid balsa nose pieces to accept these canisters. Will epoxy them in flush after sanding so the cover is barely visable. Most float setups will call for 1.5 to 3 ozs. weight to be added. These canisters weigh 7/8ths of a ounce and when filled with shot weigh 3.5 ozs. Should be just about right.

chistech

Went on vacation last week to Daytona. Rode over 1750 miles on my Road King. It was great considering that we've had nothing but cold and snow here in New England. While I was gone my buddie finished all the sheeting on the floats. They are now ready for filling, sanding, then glassing. I have currently assembled them and will be working on the mounts to my H9 Super Cub. I will have some pictures tomorrow. My buddie is a master scrimshawer by trade and his work only sells by word of mouth. I have included one picture only of his phenomenal work. This was consigned by a collector and is worth more than a luxury car. I took some pictures for him for insurance reasons before he ships it out to his customer. It is covered on 4 sides with work. It is a piece of tusk mounted on a ebony base. After looking at this you will see that working on our rc stuff is nothing for him. I have more pictures I can email anyone who's interested. They would be for private use only.

chistech

Just to answer any questions. No, it is not a photo transfered to the tooth. It is scratched in by hand and inked. It is true scrimshaw. Incredible!

chistech

I got the floats assembled for at test fit and quickly mounted them to my H9 Super Cub. Drilled the nose block and checked the fit of the ballast canisters. I will install them when we go to glass them. My buddied weighed the balsa pieces when he was sheeting them so that both floats would come out close. I need to add some plywood inside the cub for the rear mounts and put in the servo lead for the water rudders. Will be some time before I'm done with them and flying. The weather isn't even close to cooperating anyway.

chistech

Got the rear mount installed today. Ended up drilling the first set of holes too far forward. The step wasn't behind the CG. Redrilled and put in the T-nuts in. Made the rear mount out of 1/4" ply, installed the T-nuts, epoxied the whole mounting plate inplace with triangle stock. Will try and get some pictures of the plane's insides. Straightened the ends of the struts where they mount to the stock landing gear and remounted them to the fuse. The pictures show the front mounts and the spring steel strut ends mounted to the fuse.

Craig F

chistech, I wish I saw this before I finished building my Sig floats. Couple questions, is the H9 hardware adjustable
at all as far as mounting on the plane ? ie adjust the angle to mount a little one way or the other, forward/aft?
I already have them built with the plywood cross member, the thought of tearing them apart to build the pockets as you did
is not real appealing, I would have for sure from the begining, but I think it's a little late now. I know it wouldn't look have as nice,
but what about using the plywood cross member and the rest of the H9 kit? I guess that would depend on the distance between
the cross members. Mine measure from the back of the front one to the front of the back one is 14 1/4 inches and they are 1 1/4
wide is that closs to the spaceing of yours? Thanks for any advice, I have a long way to go and I'd like to get it done for this
summer. Craig

chistech

Sorry Craig,
I wasn't watching the thead much lately. I'll take some measurements tomorrow and post them here. My buddie is going to glass and paint these floats for me when the weather gets better and I will continue with the thread. The part of the mount the fastens to the bottom of the fuse can tip left or right a little either way so there is some flexibility. I can't remember the distance between the cross struts. I'll let you know.

Craig F

I'm glad you responded! I was getting worried something happened to you! I ordered the H9 float mount with 2 of the
bracket kits, I stopped building the floats and the plane 'til I get them. I want to take my time on this and do it right.
I plan on nav. lights as well as landing lights (connected to the flaps) power is a Homelite 33cc conversion. This all
started about a year ago with a few projects in between, and a "honey-do-list" !! I'm glad you're ok, I've been
checking every night. Craig

chistech

Hi Craig,
The spreaders measure from the front edge of the front one to the rear edge of the rear one 18 1/4". This is too long for your measurements. You could put some ply plates on the deck or slot the side and put them under the top deck with T-nuts. The second option would be better. You would just have to put some wood back in where you slotted the sides. Good luck and post some pictures.

Craig F

OK thanks, since I stopped the Super Cub, I took it off the bench and working on an ARF trainer. A neighbors kid has been
watching me fly, ( I have my own flying field) and I've been teaching him on the sim. I told him once he can take off and
land on the sim. I'd take him up with a buddy cord. And once he can take off and land like that I'd give him a plane and
radio. Well ,.....I owe him a plane and radio !! I want to have it ready for this weekend. Then I can get back to the Cub.

chistech

Well the weather is here to start glassing the floats to get them done and the plane on the water. We have a large fresh water pond that is unaccessible unless you know one of the beach front owners. I just found out that my brother's good friend happens to be one of those owners and he wants to learn how to fly and once he does, get a float plane. Funny how things go sometimes. My buddie has already started glassing his floats for his 1/5 J-3 and will start on mine soon. He will then paint both sets with epoxy paint. We be applying a black rubber skin to the nose of the floats to protect them when beaching. Will post pics soon.

chistech

There been so much to do that we haven't had a chance till now to start glassing and getting the floats prepared to be primed and painted. I was the event coordinator for our clubs first fun fly and that took up a lot of extra time. Now we will be putting on a club float fly in honor of one of our members who has been float flying for over forty years. This all means that we have to get the floats done now. We have finally gotten the float bottoms glassed and have started on the tops. I have included the pictures of the glassing. My buddy will be priming my set and his set of floats once the glassing is done then they will painted silver. He has a special technique to apply "dip it" type rubber to the nose of the floats that we will also be doing.

AH1G

Chistech -
It appears that I have the same Balsa USA float kit and found it on Ebay. Fortunity the kit I have does have the bulkheads. It came with a single sheet of plans, top and sideviews. One stick of 1/4 sq is broken but everything else appears to be there. I called Balsa USA today to find out if there is/was two sheets of plans as they could not ID the kit as it's too old, they also are interested in photos. It does appear that there should go on a plane of 20 lbs or less.

beau0090_99

Hey Chitech,
The floats look good. I assume you are using polyester resin. What weight glass are you using? I am starting to glass a set of foam core floats I made from scratch and am getting ideas.
Curtis

chistech

AH1G, There was just one sheet of plans that came with mine. I was pretty impressed with the quality of balsa in the box. You're not going to use the dowel spreaders are you? There are too many better options to use them. You can use the H9 hardware pretty easily and the looks are really good.I will be sanding down mine starting tomorrow to get them ready for paint. I used .75 cloth to cover mine with poly resin. Even though the bottoms are not ply the quality of the balsa makes the floats pretty rugged. I agree that 20lbs should be about tops as the floats are not that deep from top deck to keel. The GP 60 float kit builds up much deeper. I haven't weighed my Super Cub but I don't think it's much over 15 pounds.

AH1G

No, I'm not planning on dowel spreaders. In the past (30+ yrs) I used 3/16 or 1/4 piano wire sandwiched between two peices of basswood or spruce plained and sanded to a symeterical airfoil shape. It worked very well. I'm going to take a look at the hardware you are using, it looks good. Actually, with a little work, some measuring I'm going to comparethe measurementsof my whiplines and try to come up with a semi-scale set of floats for a C206.

chistech

Ok, finally got them glassed and painted. My buddie did them for me and he has been extremely busy. We do things for each other so one hand washes the other. It's what good friends are about. I wish I could use a airbrush like he does. We are going to try and maiden the Super Cub this Monday on the floats. Hope all goes well. Here are a few shots of the floats and the plane floating in my pool. They look pretty good for a 35+ year old float kit. really like the H9 hardware and the look of it.

AH1G

The floats look great and I love the hardware setup. Good luck with the maiden flight!