Super Cub custom Plywood battery box and Custom Floats.
12-01-2007, 05:49 PM
#1
prefectionist
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Join Date: Jan 2007
Location: MN
Posts: 1,919
Super Cub custom Plywood battery box and Custom Floats.
Myself and other members of the PI flight club have added aluminum landing gear to the super cub. This was originally done by using the front screws holding the battery latch cover on to hold onto the landing gear. This works, but there is a problem: The landing gear would press on the weakest part of the battery box squishing it in. One good crash and it would rip the battery box to shreds. Mine was slowly breaking over time. So I decided to replace the stock battery box with an all plywood custom job.
First thing I did was make a paper template box to adjust the size and match the angle of the back of the battery box. (my new one fits the 9 cell battery from the Park Zone spitfires)
Then I created a PDF template and used that to cut out the 3/16 inch plywood forms. (attached)
I glued thin stringers around the top and sides of the forms and then glued it all together.
To put it in the cub I glued more stringer blocks on the angled side of the box and epoxied it into the super cub.
I then filled in all the open spaces with a 50/50 mix white to gorilla glue.
I sanded the bottom smooth and epoxied a bottom plate on (I should have made it the whole width of the bottom.) It slid while drying so it's slightly crooked. This was the trickiest part because the plywood actually has to bend before and after the battery box.
I then drilled holes in the plywood for the screws and attached the landing gear and stock battery door.
The receiver is held in with a piece of servo tape.
I got a chance to test fly it in the bitter cold. With a 9 cell NiMh from my PZ spitfire it took off and flew just fine. With the aluminum landing gear I have on my cub and all the TowerKote it's getting to be on the hevy side. The aluminum landing gear also makes it a tad nosehevy.
____________________________________________
Floats:
I made a set of custom foam floats also. the plans came from:
http://www.rcgroups.com/forums/showthread.php?t=195067
I used 3/32 music wire to attach with 1/8" hold down straps holding the wire to the floats and rubber bands holding the floats to the plane.
the floats weight 4.8oz.
the aluminum with 3" du-bro wheels : 2.1oz
all up flying weight with floats : 25.8oz
First thing I did was make a paper template box to adjust the size and match the angle of the back of the battery box. (my new one fits the 9 cell battery from the Park Zone spitfires)
Then I created a PDF template and used that to cut out the 3/16 inch plywood forms. (attached)
I glued thin stringers around the top and sides of the forms and then glued it all together.
To put it in the cub I glued more stringer blocks on the angled side of the box and epoxied it into the super cub.
I then filled in all the open spaces with a 50/50 mix white to gorilla glue.
I sanded the bottom smooth and epoxied a bottom plate on (I should have made it the whole width of the bottom.) It slid while drying so it's slightly crooked. This was the trickiest part because the plywood actually has to bend before and after the battery box.
I then drilled holes in the plywood for the screws and attached the landing gear and stock battery door.
The receiver is held in with a piece of servo tape.
I got a chance to test fly it in the bitter cold. With a 9 cell NiMh from my PZ spitfire it took off and flew just fine. With the aluminum landing gear I have on my cub and all the TowerKote it's getting to be on the hevy side. The aluminum landing gear also makes it a tad nosehevy.
____________________________________________
Floats:
I made a set of custom foam floats also. the plans came from:
http://www.rcgroups.com/forums/showthread.php?t=195067
I used 3/32 music wire to attach with 1/8" hold down straps holding the wire to the floats and rubber bands holding the floats to the plane.
the floats weight 4.8oz.
the aluminum with 3" du-bro wheels : 2.1oz
all up flying weight with floats : 25.8oz
Last edited by constantCrash; 12-24-2007 at 01:05 AM. Reason: Adding floats.
12-06-2007, 02:41 PM
#5
prefectionist
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Join Date: Jan 2007
Location: MN
Posts: 1,919
I have no idea how much weight it added. A scale is on my list of tools to purchase. I'd say It added a little more than what I took off the landing gear. The aluminum landing gear was originally solid and heavy so i dremeled out a bunch of it to make up for the battery box weight. The plane flew fine with the solid aluminum gear (although somewhat sedated compared to stock with no towerkote on), So between lightening the landing gear and going to 9Cell NiMh / 3 cell Lipo it should make up for the added weight.
If anybody has an original cub could they weigh it for me? Mine is also covered and has a front end made of mostly gorilla glue (this was my first RC plane so it's early days were kind of rough).
If anybody has an original cub could they weigh it for me? Mine is also covered and has a front end made of mostly gorilla glue (this was my first RC plane so it's early days were kind of rough).
12-06-2007, 03:01 PM
#6
Member
Join Date: Jun 2007
Posts: 847
Originally Posted by constantCrash
I have no idea how much weight it added. A scale is on my list of tools to purchase. I'd say It added a little more than what I took off the landing gear. The aluminum landing gear was originally solid and heavy so i dremeled out a bunch of it to make up for the battery box weight. The plane flew fine with the solid aluminum gear (although somewhat sedated compared to stock with no towerkote on), So between lightening the landing gear and going to 9Cell NiMh / 3 cell Lipo it should make up for the added weight.
If anybody has an original cub could they weigh it for me? Mine is also covered and has a front end made of mostly gorilla glue (this was my first RC plane so it's early days were kind of rough).
If anybody has an original cub could they weigh it for me? Mine is also covered and has a front end made of mostly gorilla glue (this was my first RC plane so it's early days were kind of rough).
12-08-2007, 03:52 PM
#7
prefectionist
Thread Starter
Join Date: Jan 2007
Location: MN
Posts: 1,919
Still haven't weighed my supercub yet, but I got a quick chance to re-maiden it today.
It's Zero degrees here but it's mostly sunny and calm so I tried to go out flying. The Cub flys just fine with the new battery box. It had no effect on the COG. I used a 9 cell Nimh from my spitfire for the maiden and I think this helped with the addtional weight. Between the glue, TowerKote, battery box and aluminum gear, my cub isn't exactly light anymore. It dosen't float like the stock one, but cruses just fine at a little less than half throttle.
My next mod is to put floats on it. They are already built (homemade from Elmers board from walmart) I'm just waiting for the landing gear hold down straps to come in at the LHS
It's Zero degrees here but it's mostly sunny and calm so I tried to go out flying. The Cub flys just fine with the new battery box. It had no effect on the COG. I used a 9 cell Nimh from my spitfire for the maiden and I think this helped with the addtional weight. Between the glue, TowerKote, battery box and aluminum gear, my cub isn't exactly light anymore. It dosen't float like the stock one, but cruses just fine at a little less than half throttle.
My next mod is to put floats on it. They are already built (homemade from Elmers board from walmart) I'm just waiting for the landing gear hold down straps to come in at the LHS
06-07-2008, 07:07 AM
#9
Member
Join Date: Aug 2007
Location: Albertville, AL
Posts: 91
I appreciate your posting pics of this. I've been trying to figure out a way to mount the set of the rear struts of a GWS float. The rubber band idea rocks and I wasted no time in doing mine the ame way only moments ago. Thanks again!!!!!!!!!!
07-07-2022, 08:12 AM
#10
New Member
Join Date: Mar 2016
Posts: 7
Originally Posted by boodaghost
I appreciate your posting pics of this. I've been trying to figure out a way to mount the set of the rear struts of a GWS float. The rubber band idea rocks and I wasted no time in doing mine the ame way only moments ago. Thanks again!!!!!!!!!!
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