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S1 R/M ? on build

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S1 R/M ? on build

Post  oldguy on Thu Feb 01, 2018 5:15 pm

I have mention before i'm scratch building a Sterling S1 RM from plans.
I have question on the wing construction. The instructions call for 1 main spar 1/4 x 1/2.  I'm thinking about going with two spars, 1 across the top of the ribs and one across the lower side of the ribs.  I'm thinking about doing this because of ease of construction, and I have always built my .15 size wings this way.  I'm asking here for pros or cons on this decision I have come to.  

Another question is.  What weight should I shoot for on  the S1 RM, to be a decent flyer?


Last edited by oldguy on Tue Apr 03, 2018 4:35 pm; edited 1 time in total
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Re: S1 R/M ? on build

Post  Cribbs74 on Thu Feb 01, 2018 6:45 pm

The conclusion you have come to is a wise one. The internal spar aka “rib ripper” should be avoided. What you propose will work fine, but in all actuality it’s not really needed at all. The leading edge is the strength in that wing.

Some other tips:

Use the inner hole on the 3” bellcrank. Less is more with that big elevator.

Glass over the leading and trailing edge splits with epoxy soaked cloth or any strong thin material.

1/16” ply is all that is needed for the doubler. 25-32oz and it will manouver well.

Have Fun!

Ron
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Re: S1 R/M ? on build

Post  oldguy on Thu Feb 01, 2018 7:13 pm

Thanks for your thoughts Ron.
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Re: S1 R/M ? on build

Post  oldguy on Wed Feb 21, 2018 6:44 pm

I'm still working on the scratch S1 r/m.  Have a question for anyone, on the control rod.  What size control rod should be the minimum?  And any suggestions on what can be used?  And where to get?
Thanks


Last edited by oldguy on Wed Feb 21, 2018 10:52 pm; edited 1 time in total
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Re: S1 R/M ? on build

Post  Ken Cook on Wed Feb 21, 2018 7:42 pm

I personally use 3/32"/ .093" . Reason being is that I mainly use Sig Nylon Bellcranks or Brodak's versions, The holes in these are very close to this size only needing some mild  chamfering to allow for a proper fit. In addition, I use Dubro solder couplings on the control horn side which are designed for 4-40 clevises. Don't use 2-56 clevises if that's something you use. Of course, there's no need for clevises and a hard bend can also be used. This something I do equally. It takes a bit more time to perfect due to being very accurate. A 3/32" rod by itself is going to bow and a fairlead must be used to stiffen the rod. I use the loop of a safety pin to do this. I slide it on the pushrod and when I find it's proper location, I push it into the fuse. I rough the ends and place some epoxy into the holes that I made upon installation to retain it. The elevator of the Ring is quite large therefore the horn by itself is not enough strength and will either crack the elevator or pull out of the elevator. You need to make a small pad to under the horn top and bottom which I do using 1/64" ply to give the horn a bit more footprint and prevent the above. The wood control horn used on the early Ringmaster's is very poor and will fail usually without warning.
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Re: S1 R/M ? on build

Post  oldguy on Thu Feb 22, 2018 10:34 pm

Ken Cook wrote:I personally use 3/32"/ .093" . Reason being is that I mainly use Sig Nylon Bellcranks or Brodak's versions, The holes in these are very close to this size only needing some mild  chamfering to allow for a proper fit. In addition, I use Dubro solder couplings on the control horn side which are designed for 4-40 clevises. Don't use 2-56 clevises if that's something you use. Of course, there's no need for clevises and a hard bend can also be used. This something I do equally. It takes a bit more time to perfect due to being very accurate. A 3/32" rod by itself is going to bow and a fairlead must be used to stiffen the rod. I use the loop of a safety pin to do this. I slide it on the pushrod and when I find it's proper location, I push it into the fuse. I rough the ends and place some epoxy into the holes that I made upon installation to retain it. The elevator of the Ring is quite large therefore the horn by itself is not enough strength and will either crack the elevator or pull out of the elevator. You need to make a small pad to under the horn top and bottom which I do using 1/64" ply to give the horn a bit more footprint and prevent the above. The wood control horn used on the early Ringmaster's is very poor and will fail usually without warning.

Ken thanks for that the comments. I will go with hard bends and the safety pin fairlead.
Thanks
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Re: S1 R/M ? on build

Post  oldguy on Wed Apr 18, 2018 3:08 pm

Here's the R?M

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Re: S1 R/M ? on build

Post  Ken Cook on Wed Apr 18, 2018 3:25 pm

Keep an eye on that wood control horn, that can fail due to breaking or the glue joint failing. I've seen that more than once. I do understand that's how the original was built.
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Re: S1 R/M ? on build

Post  oldguy on Wed Apr 18, 2018 3:41 pm

Ken Cook wrote:         Keep an eye on that wood control horn, that can fail due to breaking or the glue joint failing. I've seen that more than once. I do understand that's how the original was built.

Yea, I read earlier in one of your posts about that. Its just for looks there's a nylon control horn below.
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Re: S1 R/M ? on build

Post  Ken Cook on Wed Apr 18, 2018 3:44 pm

What engine?
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Re: S1 R/M ? on build

Post  getback on Wed Apr 18, 2018 5:58 pm

I love the colors and the hind-a-way horn cool didnt even see it ! Very Happy
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Re: S1 R/M ? on build

Post  oldguy on Wed Apr 18, 2018 6:42 pm

Ken Cook wrote:     What engine?

Red Head McCoy .35
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Re: S1 R/M ? on build

Post  oldguy on Wed Apr 18, 2018 6:49 pm

Cribbs74 wrote:The conclusion you have come to is a wise one. The internal spar aka “rib ripper” should be avoided. What you propose will work fine, but in all actuality it’s not really needed at all. The leading edge is the strength in that wing.

Some other tips:

Use the inner hole on the 3” bellcrank. Less is more with that big elevator.

Glass over the leading and trailing edge splits with epoxy soaked cloth or any strong thin material.

1/16” ply is all that is needed for the doubler.  25-32oz and it will manouver well.

Have Fun!

Ron

I sure hope that weight spec is without the engine. Because she is on the heavy side. It's the first time I have used ultracote, it is pretty heavy stuff. Will see how it flys, my first real .35 size plane. It will be a learning build/ fly experience.
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Re: S1 R/M ? on build

Post  oldguy on Wed Apr 18, 2018 7:16 pm

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Re: S1 R/M ? on build

Post  Ken Cook on Thu Apr 19, 2018 4:10 am

I would say you should be good with 80 lb. That's the correct product, more importantly it's the made in the USA version. The same product is made in China and is absolutely no good. I fly .25 sized 24 oz. planes on 100 lb. This is also a requirement due to the required breaking strength of .018 steel lines. When flying a Ringmaster, your line length from eyelet to eyelet should be about 58'-6".
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Re: S1 R/M ? on build

Post  Cribbs74 on Thu Apr 19, 2018 11:01 am

oldguy wrote:
Cribbs74 wrote:The conclusion you have come to is a wise one. The internal spar aka “rib ripper” should be avoided. What you propose will work fine, but in all actuality it’s not really needed at all. The leading edge is the strength in that wing.

Some other tips:

Use the inner hole on the 3” bellcrank. Less is more with that big elevator.

Glass over the leading and trailing edge splits with epoxy soaked cloth or any strong thin material.

1/16” ply is all that is needed for the doubler.  25-32oz and it will manouver well.

Have Fun!

Ron

I sure hope that weight spec is without the engine.   Because she is on the heavy side.  It's the first time I have used  ultracote, it is pretty heavy stuff.  Will see how it flys, my first real .35 size plane. It will be a learning build/ fly experience.

No that’s with engine. I doubt the ultracote added that much weight. It’s lighter than monokote. What type of glue did you use? My Ringmaster is from an original kit and with age, repairs etc. weighs in at 38oz. It gets a little sluggish in the overheads, but is still flyable.

Ron
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Re: S1 R/M ? on build

Post  oldguy on Thu Apr 19, 2018 1:22 pm

Cribbs74 wrote:
oldguy wrote:
Cribbs74 wrote:The conclusion you have come to is a wise one. The internal spar aka “rib ripper” should be avoided. What you propose will work fine, but in all actuality it’s not really needed at all. The leading edge is the strength in that wing.

Some other tips:

Use the inner hole on the 3” bellcrank. Less is more with that big elevator.

Glass over the leading and trailing edge splits with epoxy soaked cloth or any strong thin material.

1/16” ply is all that is needed for the doubler.  25-32oz and it will manouver well.

Have Fun!

Ron

I sure hope that weight spec is without the engine.   Because she is on the heavy side.  It's the first time I have used  ultracote, it is pretty heavy stuff.  Will see how it flys, my first real .35 size plane. It will be a learning build/ fly experience.

No that’s with engine. I doubt the ultracote added that much weight. It’s lighter than monokote. What type of glue did you use? My Ringmaster is from an original kit and with age, repairs etc. weighs in at 38oz. It gets a little sluggish in the overheads, but is still flyable.

Ron
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Re: S1 R/M ? on build

Post  oldguy on Thu Apr 19, 2018 1:23 pm

oldguy wrote:
Cribbs74 wrote:
oldguy wrote:
Cribbs74 wrote:The conclusion you have come to is a wise one. The internal spar aka “rib ripper” should be avoided. What you propose will work fine, but in all actuality it’s not really needed at all. The leading edge is the strength in that wing.

Some other tips:

Use the inner hole on the 3” bellcrank. Less is more with that big elevator.

Glass over the leading and trailing edge splits with epoxy soaked cloth or any strong thin material.

1/16” ply is all that is needed for the doubler.  25-32oz and it will manouver well.

Have Fun!

Ron

I sure hope that weight spec is without the engine.   Because she is on the heavy side.  It's the first time I have used  ultracote, it is pretty heavy stuff.  Will see how it flys, my first real .35 size plane. It will be a learning build/ fly experience.

No that’s with engine. I doubt the ultracote added that much weight. It’s lighter than monokote. What type of glue did you use? My Ringmaster is from an original kit and with age, repairs etc. weighs in at 38oz. It gets a little sluggish in the overheads, but is still flyable.

Ron


Used ca and epoxy on the doublers and wing.
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Re: S1 R/M ? on build

Post  Cribbs74 on Thu Apr 19, 2018 1:51 pm

Well, I wouldn’t worry too much about it. Just fly and see what happens. Not sure where you are at in flying skill level, but it will certainly fly in circles.
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Re: S1 R/M ? on build

Post  oldguy on Thu Apr 19, 2018 2:09 pm

Cribbs74 wrote:Well, I wouldn’t worry too much about it. Just fly and see what happens. Not sure where you are at in flying skill level, but it will certainly fly in circles.

Don't like just flying in circles.
.15 video https://www.youtube.com/watch?v=ZTGsB1j1aQQ
https://www.youtube.com/watch?v=bqYFxuVMhZI
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Re: S1 R/M ? on build

Post  Cribbs74 on Thu Apr 19, 2018 9:40 pm

Ok, well I guess all you can do is fly it. It will probably be just fine.
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