stunthanger.com
Building Tips and technical articles. => Building techniques => Topic started by: Chancey Chorney on April 15, 2019, 03:17:07 PM
-
Hi all. So while building my Ringmaster Jr, I finally made a mistake, a rather good one at that. While cleaning up my model room today I realized that I forgot to install the landing gear into the wing cut-out BEFORE gluing the wing in place. So, with that said, can I simply drill a hole in the fuselage and insert a piece of brass tubing. Then cut the landing gear in half and insert each half in plase as was supposed to originally be? I think it would be a quick fine fix, but would just liek to hear it from those with more experience. I know leaving it off is also fine, but this will be the only plane I have that I can self launch, so that is why I really want to have gear installed. Thank you.
-
Option A: Drill the hole, fill it with two pieces of brass, telescoped (so you get a 1/32" wall), split the gear. This has the disadvantage that the gear can pop out fairly easily.
Option B: Drill a hole, then file it out oval fore and aft (actually, along a line at right angles to the line of the gear legs -- but if that's confusing, just make it fore and aft, it'll be close enough). Make two landing gear halves that stick all the way through the fuselage, with about 1/8" hanging out on the opposite side. Each wire will need a little dogleg so that they line up right. This adds a lot more strength -- just the holes in the plywood, without any reinforcement are enough. It's harder to make, but the gear is far less likely to pop out.
Option C: Find some profile landing gear the right size, made out of sheet aluminum. Brodaks sells it (I think), or with a lot of inspired shopping you may be able to get the right stuff from Hobby King, made out of carbon fiber.
-
How much oversize would the hole in the fuse need to be to take one wheel off and work the gear through from one side? If you did that could you strengthen the enlarged hole with a dowel or sliver of plywood once the gear is in place?
-
How about having different gear in more forward position that penetrates the plywood, and uses small landing gear straps to secure to the plywood doublers? It would need to be more straight up and down (perpendicular) with respect to the wing incidence, rather than leaning back at an angle to the wing incidence.
Personally, I like the aluminum legs screwed together through the fuselage.
An alternative would be the carpet and brick stool stooge. You need it for the other planes anyway.
If this is the only odd ball with legs, you still need the human or mechanical stooge.
-
Another alternative, I just looked at an old Ringmaster my wife found at a yard sale. They apparently made the same mistake so they put the gear in through the engine mount opening and angled it rearward rather than through the wing slot angled forward. I can take a picture if you like.
-
Here's a picture of a Slight Freak (uh -- Flight Streak) with gear built to my Option B, above. I was trying to take a picture of the tank at the time, so the gear doesn't show well, but if you squint you can see the end of the gear from the other side, in between the tank and the wire going into the fuselage.
(https://stunthanger.com/smf/open-forum/hey-mark!-thanks-for-the-twister-uh-flight-streak/?action=dlattach;attach=92134;image)
-
Thank you all for the ideas and help. They are all great recommendations. The quickest and easiest would be to split the gear in half as I do not have any spare wire here to bend up a new set. But if that is still the case, it would not affect the finishing of the model. I have to get teh brass tubing and straps anyways so would pick up a new piece of wire to form a new set. Also George, a picture would be greatly appreciated if it would not be a big bother, but I do feel I have the idea in my head and also believe that there is enough room in the engine area for it if I decide to go that route. I will heed over the ideas and decide on one hopefully later today or tomorrow.
And also George, the wheels are not yet attached, but due to the bends in the gear, I think that the hole would be a decent size. Well, 1/8" wide, but length would be unknown till I got into it. I will possibly find a scrap piece of 1/8" wood and see. Despite the mistake, I am actually kind of happy as I was always worried about the gear popping up and into teh wing. Either way, that will now be eliminated.....
-
Yes Tim, I see it well. Thank you for your time. And I do kind of like that as I would not need the brass tubing sleeve.
-
Yes Tim, I see it well. Thank you for your time. And I do kind of like that as I would not need the brass tubing sleeve.
It's my favorite method of mounting wire gear in a profile (assuming I'm bending the gear). If you remember to do it before the wing goes in, and if you have a drill bit that'll track straight next to another hole, you can make two holes adjacent to each other. You need a drill bit ground to a "sorta Forstner", or maybe even a real Forstner.
-
How about converting to wing mounted gear. They look so much more “pro”!
-
There's no question that it would look good, but for a first time bigger build, I will resort back to a fuselage mounted landing gear. On my next one, that is something to consider so will save the questions on how to do it for then. I am just thinking that it would require a lot more work to do it as I would have to beef up the wing I am sure.
-
Been doing the brass tube split thing all the way back to the 60's. Works great. I normally use a longer top piece and 2 clamps but one is enough if you use brass. W/O the tubing the inside of the hole will start to elongate and the wheels will start to toe out and grab on takeoff but that takes a while. Oh, and make sure that the tubing recesses into the fuselage enough to allow for the bend in the wire.
Good luck _ Ken
-
Cut a slot from the engine bay to the leading edge, slide the wire gear in place then glue a piece of lite ply in the slot.
MM
I've seen it done by sealing the slot on the inside and just leaving it there so you can remove the gear and use them for what they were born to do - slow combat over grass.
Ken
-
You could bend a new, removable, one piece landing gear to straddle the fuselage as shown in the photos.
-
Well Bill, I am really liking that idea. Seems easy enough. I now have so many options and ideas. Thanks to all again for your ideas and help.
-
Chancy, Paul and I use the split gear idea regularly for our profile models with 1/2" thick fuselages. If you are worried that the gear might pop out because your fuse is thinner just drill two holes (one above the other and insert brass tubing). The slight difference in height won't amount to a hill of beans and you can always adjust the legs so the model sits straight on a level surface. IMHO, a two leg L.G. is always safer for taking off from rough fields. PS, I've got lots of wire.
-
RSM distribution
http://www.rsmdistribution.com/index.php
Profile Landing Gear, Long Duralloy Gear perfect for models such as Twister, Banshee & P40 Part Number: PLGL
RSM Price $14.99
Add To Cart
Profile Landing Gear, Short Duralloy Gear perfect for Ringmaster, Flite Streak & Yak 9 profile models Part Number: PLGS
RSM Price $13.99
Add To Cart
-
Thanks Dennis. I might have to take you up on some wire if I don't get to the LHS before field clean up day. I was doing a good job on the plane before this arose.....
-
Well, it is now done. And the winner is 'Option B' by Tim Wescott. I was bored, but had no wire handy. Then I saw a coathangar sitting doing nothing. Cut the wire, cleaned it all up and removed varnish. Bent the gear legs and installed. I just had to slightly adjust the strap mounting locations, but was no big deal. Tomorrow I will do a heat treating to the legs if I have time, and they should be good to go. Even if teh heat treat doesn't work out as planned, I can easily make new legs when I get the proper wire. Sorry I did not take any pictures, but when I reinstall it for a test fit, I will take them then. Thanks all for the help.