Advice on Super Skybolt (engine mount and servos)
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Advice on Super Skybolt (engine mount and servos)
Hello, I'm building a Super Skybolt and I have a few questions. I've built planes for years, but nothing over a size .46, so this is the biggest one and I wanna make sure I'm doing it right. Ihave bought a YS 110 for the plane and was wondering what kind of engine mount to get. The only mounts I've ever used are standard ridgid two-beam mounts. The plane came with one like that, but I'm thinking maybe Ishould invest in something nicer. Any suggestions?
Second, Ibought a 7 channel Spektrum (DX7) for the radio. In every plane I've ever built I put the elevator and rudder servos in the middle (over/under the wing). But I'veseen a lot of people in the past put them in the tail section. I kind of like this idea because it will free up area in the middle for the oil tank for a smoke system (since only the throttle servo will be in there). Will the weight of the servos in the rear be too much though? I was thinking since the radio only came with 4 standard sized servos and Ineed to buy more, maybe I should buy lighter weight ones for the elevator/rudder. I'll probably have to use two servos for the elevator also, as it's split in two.
Any thoughts would be very much appreciated!
Thanks!
Second, Ibought a 7 channel Spektrum (DX7) for the radio. In every plane I've ever built I put the elevator and rudder servos in the middle (over/under the wing). But I'veseen a lot of people in the past put them in the tail section. I kind of like this idea because it will free up area in the middle for the oil tank for a smoke system (since only the throttle servo will be in there). Will the weight of the servos in the rear be too much though? I was thinking since the radio only came with 4 standard sized servos and Ineed to buy more, maybe I should buy lighter weight ones for the elevator/rudder. I'll probably have to use two servos for the elevator also, as it's split in two.
Any thoughts would be very much appreciated!
Thanks!
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RE: Advice on Super Skybolt (engine mount and servos)
have a look through this thread, lots of good info here.http://www.rcuniverse.com/forum/m_60...tm.htm#9397447
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RE: Advice on Super Skybolt (engine mount and servos)
I have used the GP black nylon mount with my YS110 without problems. As far as servo's go, nothing special is needed. I just used a single servo for the rudder on this plane.
The key here will be to keep the airframe very very lite. You will need to put all the servo's as far forward as possible as this kit builds tail heavy.
As mentioned, there are a couple of build threads on this plane.
The key here will be to keep the airframe very very lite. You will need to put all the servo's as far forward as possible as this kit builds tail heavy.
As mentioned, there are a couple of build threads on this plane.
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RE: Advice on Super Skybolt (engine mount and servos)
Were you aware that Great Planes has discontinued this kit? You possibly have one of the last ones to be made.
Have to agree - keep it light and keep the weight forward - "builds tail heavy" is usually a fact of life with this model. I use digital DS821 servos (the ones that come with your DX7) for all my planes, on all except throttles and flaps. I also use pull-pull rudders on all my planes including my Skybolt.
For the elevators I pinched someone else's idea and made a torque rod linking the left and right halves to avoid uneven movements from the offset elevator servo. It does work just fine, but if I were to do it again I'd be looking for something like [link=http://www.centralhobbies.com/control_linkage/bellcrnk.html]one of these[/link] dual elevator bell cranks. They fit into the fuselage towards the tail and take a single pushrod, with dual pushrods linking to the elevators.
I found a discussion about unequal aileron movement using the system that GP includes with their kit. An easy remedy is to use these [link=http://www.sigmfg.com/cgi-bin/dpsmart.exe/MainMenuFV4.html?E+Sig]Aileron Interconnect Horns[/link] by Sig.
As for the engine, I used a regular engine mount (think it was a Great Planes one) for my ASP120 four stroke, till I replaced it with an OS160 twin cylinder four stroke. You could use one of those rubber mounted aluminium mounts if you think your YS will vibrate too much but I wouldn't bother - they're very expensive and you're probably better off spending the money on some other pat of the plane (I can really recommend on-board glow drivers).
You'll find the kit has a cowl & wheel pants made from ABS plastic - these are rubbish and for some reason (probably cost) GP thought it'd be a good idea to have the builder glue two halves together, fill the gap with (heavy) automotive filler, spend hours sanding etc. You can get good quality fibreglass replacements from [link=http://www.fiberglassspecialtiesinc.com/catalog.htm]Fibreglass Specialities[/link]. I bought their cowl and am very happy with it, but didn't know about the 'glass wheel pants till after putting in all the work on the GP ones, so I stuck with them.
When you're gluing in the firewall, use the strongest strapping you can find and wrap it as tightly as you can around the planks that form the forward fuselage. I failed to do this properly and had to go to great lengths to build up the inner part of the fuse and sand away the outer to get the correct taper on the nose so that the cowl would fit over.
Finally, a personal request - please don't use the standard colouring scheme on the box. There's a huge thread on this plane called the "super skybolt clubhouse" or something similar and there's hundreds of pics of colour schemes in there (including mine). Since it's a real plane you can also google images of real colour schemes for inspiration too. Just make sure the underside of the bottom wing's a contrasting colour so you can tell top from bottom while in flight - I made mine all black and after a couple of scares added a pair of large, white "ace of spades" symbols for my own comfort.
Have to agree - keep it light and keep the weight forward - "builds tail heavy" is usually a fact of life with this model. I use digital DS821 servos (the ones that come with your DX7) for all my planes, on all except throttles and flaps. I also use pull-pull rudders on all my planes including my Skybolt.
For the elevators I pinched someone else's idea and made a torque rod linking the left and right halves to avoid uneven movements from the offset elevator servo. It does work just fine, but if I were to do it again I'd be looking for something like [link=http://www.centralhobbies.com/control_linkage/bellcrnk.html]one of these[/link] dual elevator bell cranks. They fit into the fuselage towards the tail and take a single pushrod, with dual pushrods linking to the elevators.
I found a discussion about unequal aileron movement using the system that GP includes with their kit. An easy remedy is to use these [link=http://www.sigmfg.com/cgi-bin/dpsmart.exe/MainMenuFV4.html?E+Sig]Aileron Interconnect Horns[/link] by Sig.
As for the engine, I used a regular engine mount (think it was a Great Planes one) for my ASP120 four stroke, till I replaced it with an OS160 twin cylinder four stroke. You could use one of those rubber mounted aluminium mounts if you think your YS will vibrate too much but I wouldn't bother - they're very expensive and you're probably better off spending the money on some other pat of the plane (I can really recommend on-board glow drivers).
You'll find the kit has a cowl & wheel pants made from ABS plastic - these are rubbish and for some reason (probably cost) GP thought it'd be a good idea to have the builder glue two halves together, fill the gap with (heavy) automotive filler, spend hours sanding etc. You can get good quality fibreglass replacements from [link=http://www.fiberglassspecialtiesinc.com/catalog.htm]Fibreglass Specialities[/link]. I bought their cowl and am very happy with it, but didn't know about the 'glass wheel pants till after putting in all the work on the GP ones, so I stuck with them.
When you're gluing in the firewall, use the strongest strapping you can find and wrap it as tightly as you can around the planks that form the forward fuselage. I failed to do this properly and had to go to great lengths to build up the inner part of the fuse and sand away the outer to get the correct taper on the nose so that the cowl would fit over.
Finally, a personal request - please don't use the standard colouring scheme on the box. There's a huge thread on this plane called the "super skybolt clubhouse" or something similar and there's hundreds of pics of colour schemes in there (including mine). Since it's a real plane you can also google images of real colour schemes for inspiration too. Just make sure the underside of the bottom wing's a contrasting colour so you can tell top from bottom while in flight - I made mine all black and after a couple of scares added a pair of large, white "ace of spades" symbols for my own comfort.
#5
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RE: Advice on Super Skybolt (engine mount and servos)
Put the servos near the rear of the radio compartment. That will give you room to slide the tank back and add a smaller tank for oil where the fuel tank would normally be.
There is an open area on the bottom of the nose just forward of the landing gear. Instead of sheeting this area, create a hatch there. It is the perfect place to store the smoke pump.
Here's a vid of my Skybolt with smoke:
http://www.minnartist.com/RCU/grafix...t_high_res.wmv
There is an open area on the bottom of the nose just forward of the landing gear. Instead of sheeting this area, create a hatch there. It is the perfect place to store the smoke pump.
Here's a vid of my Skybolt with smoke:
http://www.minnartist.com/RCU/grafix...t_high_res.wmv
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RE: Advice on Super Skybolt (engine mount and servos)
I too am building a Super Skybolt, one of the two I have. I'm going to use an OS 120 pumper in it. Note that the plans specify that the thrust washer should be 6 1/16" from the firewall and should have an isolation mount. I have an OS mount however if used it would place the thrust waser at 5 3/4". I took a chance and bought a set of wheel pants from Tower for there ARF Skybolt, they are glass, assembled and painted AND they are the same size and shape. Iv'e made a mold for the cowling and have pullled one part from it so far. Man I detest ABS.
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RE: Advice on Super Skybolt (engine mount and servos)
ORIGINAL: AH1G
I too am building a Super Skybolt, one of the two I have. I'm going to use an OS 120 pumper in it. Note that the plans specify that the thrust washer should be 6 1/16'' from the firewall and should have an isolation mount. I have an OS mount however if used it would place the thrust waser at 5 3/4''. I took a chance and bought a set of wheel pants from Tower for there ARF Skybolt, they are glass, assembled and painted AND they are the same size and shape. Iv'e made a mold for the cowling and have pullled one part from it so far. Man I detest ABS.
I too am building a Super Skybolt, one of the two I have. I'm going to use an OS 120 pumper in it. Note that the plans specify that the thrust washer should be 6 1/16'' from the firewall and should have an isolation mount. I have an OS mount however if used it would place the thrust waser at 5 3/4''. I took a chance and bought a set of wheel pants from Tower for there ARF Skybolt, they are glass, assembled and painted AND they are the same size and shape. Iv'e made a mold for the cowling and have pullled one part from it so far. Man I detest ABS.
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RE: Advice on Super Skybolt (engine mount and servos)
I had a YS91 on mine and all I did was to add a strip of rubber (Cut from an old inner tube) between the standard mount and firewall. This is something I often do with any engine mount, not something special I did for this plane.
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RE: Advice on Super Skybolt (engine mount and servos)
For the OS 120 4-stroke, it does specify an isolation mount, A Jtec mount to be exact. Unfortunatly I tried to obtain one from Jtec and was told they will not have any in the forseeable future. So I'm going to use a Dubro isolation mount. I wasn't sure about the cowl so I built my own mold and pulled my first part (epoxy/glass) on Sunday; It looks pretty good if I say so myself.
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RE: Advice on Super Skybolt (engine mount and servos)
Since this plane is so tail heavy any body thing one of the new small gas engines would work, such as the Evolution 26 or DLE 30? Would make smoke easy too!!
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RE: Advice on Super Skybolt (engine mount and servos)
I don't know anything about gas and never thought about it. I would love to give it a try instead of the OS 120. What things would have to be considered? Would it even be a good option for a first gasser?
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RE: Advice on Super Skybolt (engine mount and servos)
Mooseflier,
The planes show a "Y" for the elevator controls, so a single servo should be all it needs. The plans are a litte old school with the binding and soldering of the control rods. The cabines show the same method. I thought of building CF cabines and struts for mine and utilizing a a socket and slot arrangement instead. They would be installed with screws and nuts to the wings and permanently mounted to the fusalage. As I see it, it would be about the same weight, be more aerodynamic, and something else to putz with.
To Minnflyer,
G20 huh, I'm going to give this some serious thought. I'm at a point that I need to make a decision before I proceed with the fusalage any further.
The planes show a "Y" for the elevator controls, so a single servo should be all it needs. The plans are a litte old school with the binding and soldering of the control rods. The cabines show the same method. I thought of building CF cabines and struts for mine and utilizing a a socket and slot arrangement instead. They would be installed with screws and nuts to the wings and permanently mounted to the fusalage. As I see it, it would be about the same weight, be more aerodynamic, and something else to putz with.
To Minnflyer,
G20 huh, I'm going to give this some serious thought. I'm at a point that I need to make a decision before I proceed with the fusalage any further.
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RE: Advice on Super Skybolt (engine mount and servos)
Mooseflier,
I think I need to apologize to you, we got off subject regarding your original questions.
Did your questions get answered?
When you get ready for a cowl please let me know and I'll send you a epoxy/glass one and hope it suits your needs.
Brian
I think I need to apologize to you, we got off subject regarding your original questions.
Did your questions get answered?
When you get ready for a cowl please let me know and I'll send you a epoxy/glass one and hope it suits your needs.
Brian
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RE: Advice on Super Skybolt (engine mount and servos)
G-20 sounds a bit large for this airplane, I've heard of a lot good thing about 1.20 four strokes for the super skybolt. Anyone needing fiber glassing advise I can help.
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RE: Advice on Super Skybolt (engine mount and servos)
Thanks for the fiberglassing offer however, thats not one of my shortcomings, I have about 37 years of experience in glass work.
I'm still looking for a J'Tec OS 120 isolation mount so, the project is on hold until I find one.
I'm still looking for a J'Tec OS 120 isolation mount so, the project is on hold until I find one.
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RE: Advice on Super Skybolt (engine mount and servos)
I agree Dubro does make a nice mount, I have several. Unfortunately it places the engine 15/16" too far forward and will not work in this application. The Skybolt is usually nose heavy anyway and I surely don't want to add a pound of lead to the tail. With an OS mount it is 5/16" short; I could add a spacer and rubber between the mount and firewall but I'd rather have the J'Tec mount. The GP kit (old) does specify the J'Tec with a 120 and as I plan to sell this one I'd like to done perfectly. I'm old school...
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RE: Advice on Super Skybolt (engine mount and servos)
Actually it tends to come out very tail heavy - even with an OS 160 twin I needed to add 60 grams of lead to the engine mount. Before the 160 I ran an ASP 120 4 stroke on an OS 60-120 solid mount and ran 180 grams of nose weight.
You really don't need an isolation mount with the big 4 strokes, both of mine were solid mounted and never had a problem.
You really don't need an isolation mount with the big 4 strokes, both of mine were solid mounted and never had a problem.
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RE: Advice on Super Skybolt (engine mount and servos)
Hmmmm. On my last one I had to add just shy of 2 oz to the tail. Lasted three years until a tree reached out and snatched it.