Unionville 6' Otter
#1

I'm framing up a Unionville 6' Otter for a club member and since it's not a commonly modeled subject, I thought I'd post some pics here.
The wood quality in the kit is very good, but this must be best described as a "builder's" kit, since very little is done for you. It's really more like scratch building with the ribs cut out for you. I also am making several mods to make the plane more reliable to operate and set up.

I sacrificed scale appearance in the stab mounting area in name of safety. The recommended method is failure-prone IMO.

The plans call for rubber bands, but the owner requested a bolt-on wing system

The wing is ready to cover minus the center section fairing, while the fuse still needs the firewall installed as well as all the bits that will give it a rounded shape.
The wood quality in the kit is very good, but this must be best described as a "builder's" kit, since very little is done for you. It's really more like scratch building with the ribs cut out for you. I also am making several mods to make the plane more reliable to operate and set up.

I sacrificed scale appearance in the stab mounting area in name of safety. The recommended method is failure-prone IMO.

The plans call for rubber bands, but the owner requested a bolt-on wing system

The wing is ready to cover minus the center section fairing, while the fuse still needs the firewall installed as well as all the bits that will give it a rounded shape.

#3

ORIGINAL: crash bandicoute
is this some kind of short kit or built from a set of plans? looks pretty nice so far.
is this some kind of short kit or built from a set of plans? looks pretty nice so far.
I mentioned it was like scratch building, because most of the fuse is built from 1/4" balsa sticks that you have to cut/fit yourself. It takes a lot of care to keep everything square and true, because, the kit has none of the modern interlocking features that you get, for example, with a Great Planes or Goldberg kit.
#4

Join Date: Apr 2006
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Bipes: Your construction is excellently done. I have just downloaded the website so I can purchase a Beaver also. It is one of my most favorite civilan aircraft. Keep us on track with your build.
Rich
Rich
#6

Here's an update: I mocked-up the fin/rudder. Boy the sucker is big, see standard size servo for scale.

Built the wing fairing to blend the wing to the fuse. A little fiddly to get right, but balsa is so forgiving. Mess up, glue another piece on and sand again to fit!


Firewall installed. This one had me head scratching for a while, because you have to figure out exactly where it should be placed. Using the plans, I marked the engine thrust line on the fuse sides and on the firewall. Once that was done, I had reference points to make sure everything lined-up as it should.

Built the wing fairing to blend the wing to the fuse. A little fiddly to get right, but balsa is so forgiving. Mess up, glue another piece on and sand again to fit!


Firewall installed. This one had me head scratching for a while, because you have to figure out exactly where it should be placed. Using the plans, I marked the engine thrust line on the fuse sides and on the firewall. Once that was done, I had reference points to make sure everything lined-up as it should.

#7

Not much apparent progress today. In a sense I actually moved "backwards" a little after determining that the supplied engine would never fit into the cowl with the stock firewall setup. The only solution I could see was to recess the engine mount which meant cutting into the freshly installed firewall.

The engine is mounted in a way to have the exhaust come out the bottom of the plane and position the cowl cut outs in a position that will be less conspicuous. I also cut away part of the engine mount to allow me to slide the engine back as far as possible. This setup will place the engine inside the cowl and have the prop about 1/4" past the nose.

The engine is mounted in a way to have the exhaust come out the bottom of the plane and position the cowl cut outs in a position that will be less conspicuous. I also cut away part of the engine mount to allow me to slide the engine back as far as possible. This setup will place the engine inside the cowl and have the prop about 1/4" past the nose.

#8

Made some progress last couple of days.

Carving and sanding then sheeting the nose section proved to be the most challenging part of the build so far. The sheeting conformed to the compound curve at the front once I had it soaked with water.

Pooch, however, is not impressed.

Carving and sanding then sheeting the nose section proved to be the most challenging part of the build so far. The sheeting conformed to the compound curve at the front once I had it soaked with water.

Pooch, however, is not impressed.


#10

Thanks Prr6100, I got a fair bit done in last few days, the fuse is basically ready to cover.
Firts I assembled and test fitted the tail feathers, look at that rudder, boy is it BIG.


Next I started sheeting the bottom of the fuse, which was fairly strait forward. Note the use of small tabs to help locate the sheeting along fuse side.

Next, I started installing the formers running towards the back of the plane and here is where I encountered a slightly annoying problem:

The formers aren't sized correctly, so that in order to get the stringers to sit properly, they have to be ressessed into some formers, while over others, they have to be shimmed. Not difficult to do, but quite fiddly.
The end result was pretty good, I think.
Firts I assembled and test fitted the tail feathers, look at that rudder, boy is it BIG.


Next I started sheeting the bottom of the fuse, which was fairly strait forward. Note the use of small tabs to help locate the sheeting along fuse side.

Next, I started installing the formers running towards the back of the plane and here is where I encountered a slightly annoying problem:

The formers aren't sized correctly, so that in order to get the stringers to sit properly, they have to be ressessed into some formers, while over others, they have to be shimmed. Not difficult to do, but quite fiddly.
The end result was pretty good, I think.

#13

The request by the owner was for a frame-up job, and the plane is now ready to cover.
Here's the strut setup. In the close-up pic, note fiberglass applied to area where the strut meets the wing. This will make it more ding and scratch resistant.


And the completed OTTER in all its glory

Oh, one major deviation from the plans was the use of an aluminum landing gear. The kit comes with lengths of 5/32" and 3/32" music wire that you have to bend and solder yourself. It was a lot easier and quicker to source a aluminum unit.
Here's the strut setup. In the close-up pic, note fiberglass applied to area where the strut meets the wing. This will make it more ding and scratch resistant.


And the completed OTTER in all its glory


Oh, one major deviation from the plans was the use of an aluminum landing gear. The kit comes with lengths of 5/32" and 3/32" music wire that you have to bend and solder yourself. It was a lot easier and quicker to source a aluminum unit.

#19
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Well this is an old thread but I have a Unionville Otter in my basement I bought prior to 1990. It was partially built and still sitting in the box. Not sure I will every complete it as my heart has gone to RTF and multicopter. Maybe some year I will get it done. Love the pics above of the Otter, at least now I know what I have left to do.
#21

I'm not sure the kits are still in production, but Pinnacle Hobbies had a small inventory last time I checked.
http://www.pinnaclehobby.ca/
http://www.pinnaclehobby.ca/
#22
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Hi All
I bought this kit quite some time ago from a canadian homepage which is no longer existing i think (scalercmodels.com or anything like that)
I was happy since i couldn't find any good kit here in switzerland.
I am currently about as far as you were in the first picture and i plan to add some of mine here too.
The kit is very nice and it starts to look good now (: i couldn't find much information about this kit but I'm glad to finally compare my model to someone elses.
The manual is sometimes a bit overcomplicated.. i plan change the wing mount a little bit and the landing gear is also not very nice.
The biggest experiment i am facing is that i want to put a brushless inside.
Do you have pictures of the finished model?
I am very interested in the outcome of your project.
Keep up the good work!
I bought this kit quite some time ago from a canadian homepage which is no longer existing i think (scalercmodels.com or anything like that)
I was happy since i couldn't find any good kit here in switzerland.
I am currently about as far as you were in the first picture and i plan to add some of mine here too.
The kit is very nice and it starts to look good now (: i couldn't find much information about this kit but I'm glad to finally compare my model to someone elses.
The manual is sometimes a bit overcomplicated.. i plan change the wing mount a little bit and the landing gear is also not very nice.
The biggest experiment i am facing is that i want to put a brushless inside.
Do you have pictures of the finished model?
I am very interested in the outcome of your project.
Keep up the good work!
#23
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Join Date: Apr 2007
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There is a build of a Norseman, which is similar, on RC Canada. If you like I can try to send you the link, you may be able to find it on RC Canada, have you looked at that site?