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Aug 10, 2012, 08:59 PM
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Few things are more cool than seeing your own airplane getting built!

Adios - Paul
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Aug 10, 2012, 10:43 PM
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thanks the storage just kinda happened as I already have those pegs up in my shop.

as for my learning curve on this first build. I can definitely tell you that I will know much more my next one. The crazy thing is I was building it so that I could have a glider to fly and now sometimes I feel like I'm flying so I can justify the building process. In other words I thought I would give building a shot and now I think I have the bug. As this build is comming closer to an end I am already considering what my next build is going to be.

One question, I have been avoiding thinking about a problem I caused while learning to sand. I made a preaty deep groove in a spar cap or two. Should I grind it out and replace it or could I get away with grinding out just the spot that has the group and replacing it and sanding it to match or should I fill it with something? I am kind of leaning towards grinding out just be affected peace and replacing that then sanding it down to match the rest. Pics to describe the issue to follow in a min.
Aug 10, 2012, 11:05 PM
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Agree Paul, actually the next thing I'm going to try to figure out is how you did the posts on the inside of your fuse.
Aug 17, 2012, 09:40 PM
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Top spar fixing.....

Hey, I just saw your pictures. The thing to keep in mind is that the top spar is operating under Compression unless you are flying inverted or doing nose-dive loops(not likely either one).

So, if you can skill fully sand the steep side of that notch to match the less steep side, then skillfully make a "patch" piece of wood sanded to insert into that space and glue it very securely (I would recommend pre-glueing with yellow glue, sanding if needed, then re-glue and clamp it), let it dry then very skillfully sand it down to match the rest of the spar, then you've got the hard part done. It will help structural strength and cosmetically and give you the "normal" air flow of the kit as designed. Just do it slow and steady and don't be in a hurry.

Then, just try to put more shear webbing in-between the spars in that spot just to give it that much more support. Then you should be OK.

Hopefully all that makes sense.

I've repaired completely shattered and broken wings twice with similar methods and they're holding up fine. I don't even hesitate to put them in a short dive, pull up on the nose and do a backflip loop. If I hesitate, it's for other reasons and not the spots that I repaired.

Adios - Paul
Aug 17, 2012, 09:47 PM
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Hey, is that over-sanded-notch in Balsa covering/capping over a hardwood spar underneath?

If so, then if it's merely a balsa spar-cap and not a load-bearing hardwood spar, then you can just make a piece of balsa to fit in the notch, glue it in, sand it nice and even, and go from there if an actual load-bearing hardwood spar underneath has not been compromised.

Hope that doesn't make things more confusing.

Adios - Paul
Aug 17, 2012, 10:32 PM
The King Moonracer of balsa.
Windependence's Avatar
Fickle flyer, you only over sanded the balsa filler cap not the actual spruce spar. This will have zero impact on the integrity of your wing. The only reason for that 1/16 balsa cap on the spruce spar is to bring it up in height to the rib caps.

Aug 17, 2012, 11:46 PM
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Ok thank you fellas. At first i thought that was the case then i think i started over thinking it. I will just add new piece and sand to match.
Aug 30, 2012, 07:09 PM
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The wings are almost ready to be joined. I have some pics of them just dry fitting.

I need to finish the spoilers. I am almost sure I am going with servos in the wings as it seem seems to be able to adjust them with my radio and adjust them separately. If I end up that way I will need to build something to mount them on in the wing. Should not be too hard I am sure.

The main issue I have run into is with the fuse. It was turning out a bit crooked and I had to push one side forward to make it straight. Good news is that it worked and the fuse is almost completely straight. The bad news is that the braces are crooked. It seems that it is plenty strong but I don't know. Does anyone have input as to weather I should just scrap this one or if I should just make it work (seems fine now).

Either way I think I will build a new one at some point if for no other reason than to just learn how to make a straight one. I think I could do it now I just messed up with some stuff as it was my first fuse. I would be much more careful now and I believe I could get it straight my second try. Also, I was thinking I would not mind doing a bigger triangle stock and making the fuse a bit more aerodynamic. Of course if it flew fine I would probably wait till I crash it as I have a couple of other projects I would like to try.

Other than that just doing final sanding / shaping tasks and I should have the wing ready very soon.

The tail group is pretty much ready to be covered.

One question. Does the wood have to be mostly perfect or can the covering cover a lot of the inconstancy. Just curious as I feel like I may be overdoing the sanding and shaping bit.
Aug 30, 2012, 09:35 PM
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Cool Pictures!

Hey, nice job so far.

Spoilers- I may end up having to put a servo in each servo bay and wire my wings for my 2M Spirit since I ran out of room to put a single mini servo for pull strings after narrowing and lowering my fusalage.

Fusalage- When you talk about crooked "braces", do you mean the bulkheads? If you're talking about the bulkheads, then no, it won't matter as long as things fit, your wings sit on your fusalage straight(and lined up with the tail pieces). If making your bulkheads a little crooked is the price you pay for getting your fuselage nice and straight and lined up nice on the outside, you'll be fine. At the worst case, a not-quite-straight fusalage looks worse than it affects flight. Straight is better flying, but my first plane was a bit off-center on the fusalage and it flies fine for what it is (HOB 2x4).

Triangle stock- Yes, I would advise putting them in your corners and rounding your corners and making things as nice, round and smooth and aerodynamically clean as possible. If you do this with EVERYTHING it will make a noticable improvement in how it flies, penetrates into a breeze when wanted, minimizes sink, maximizes "Go", etc.

Other Streamlining if you want to spend the time- Keep all switches inside, if using 72Mhz, keep that antenna wire mostly inside the fusalage and not dangling, put your wing hold-down dowels inside the fusalage and not sticking out(it's a bit of a project, but it's sooooo much cleaner aerodynically). Keep those trailing edges of the wings, elevator, rudder and nice and tapered and almost "sharp"(if you're really into it, make the last 1/4" of the wing trailing edges spruce and sand down to 1/32" or less- but that can wait until you really want to focus on streamlining, or go ahead). I think everything I mentioned is posted on my Spirit thread in case you want a pictorial.

Sanding away inconsistency vs covering up with covering? -Hmmm, It depends. If it's not much, it probably won't matter much if any, if there are things really "dipping inward" you might want to fill in with scrap wood and sand to shape, if things "stick out" much, I would sand them down so everything is nice, even and smooth. You'll be glad you did.

However, The "main thing" is having everything aligned so that your plane's surfaces aren't fighting each other through the air. For instance, if you have a warped wing, it's fighting the air some, then you'll have to compensate with your rudder left/right off-center to make it fly straight and thus fighting your wing's warp and that will make drag and less effective manuevering ability.

I'm going to guess outward alignment probably counts most here in regard to the questions you asked. Hopefully all this helps more than confuses.

Adios - Paul
Last edited by Pauliwog; Aug 30, 2012 at 09:41 PM.
Aug 31, 2012, 03:45 PM
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Fuse update

Here it is. I think I am just going with it for now. You really have to look to be able to tell it is a bit off, and it is only off in the curve of the side. it is straight.
Aug 31, 2012, 10:46 PM
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You'll be fine, almost every one of us at some point (like me and my HOB 2x4) has had that happen, and usually with the first plane. As long as you get your wings, horiz and vert stabs all nice and lined up, it'll fly fine and probably only notice it when you look for it.

I've heard of people cutting the fusalage apart or soaking in the sink to undo the glue, etc and re-gluing and I'm not sure how much that's really neccessary since it's largely aesthetics at the speeds this plane will be flying. Besides, the Sig 2M Riser is known for being a good handling, nice flying plane, not a high performance speeder, but still a nice flying plane so I think you'll be fine.

Adios - Paul
Sep 01, 2012, 09:35 PM
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doc993's Avatar
Ditto what Pauly wog says.You also have a little room when it comes time to sand the radius's. If you sand slowly and round the edges nicely you wont see it.It will be fine.Your build is going pretty well ,good pictures to.
Sep 01, 2012, 09:41 PM
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it's hard to get the fuse exactly straight - i have a gentle lady with a warp in the fuse and it flies great - i just don't ever look at it too close - besides, if all is right, they spend most of the time as a speck in the sky, right?

i've never built the riser 2m, but i have heard they fly well - year ago, i can remember reading an article about a girl who won a nationals competition flying a riser 2 meter
Sep 01, 2012, 09:44 PM
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my point about the riser 2m winning the nationals competition is, now that i think about it, not as interesting as the fact that a girl won the nationals - lol

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