2015 Design Contest - Half-A-Wing
10-01-2015, 08:07 PM
#51
Thread Starter
Thanks for the information on the prop plate. Comes off easy when you know how to do it. Didn't have a phenolic washer so I made one out of pop can material. Will see how it holds up. Hope it will get me by for a few flights. If not I'll round up something else. From only making a few runs with the motor it was wearing fast.
Moved the balance back closer to 18%. Did every thing on Tue and was ready to go Wed for a another test flight. The wind has just been to strong the last two days. Will probably be the same through the weekend.
Moved the balance back closer to 18%. Did every thing on Tue and was ready to go Wed for a another test flight. The wind has just been to strong the last two days. Will probably be the same through the weekend.
10-01-2015, 08:38 PM
#53
Sacrifice material phenolic although tough will thin out over time.
A thin steel washer large enough to cover the entire rub zone will delay some wear.
The best material one could fabricate from would be ceramic. The pop can aluminum
is a good idea and thin just watch the slop over time don't want that con rod pin from the
crank shaft rubbing on the reed valve. Good job you took the time to add the thrust washer.
The extreme method I have used with a TD was adding thrust bearings for near 0 loss under load.
A thin steel washer large enough to cover the entire rub zone will delay some wear.
The best material one could fabricate from would be ceramic. The pop can aluminum
is a good idea and thin just watch the slop over time don't want that con rod pin from the
crank shaft rubbing on the reed valve. Good job you took the time to add the thrust washer.
The extreme method I have used with a TD was adding thrust bearings for near 0 loss under load.
10-08-2015, 10:52 AM
#54
Thread Starter
I made two more tries . Both crashed at take off . I think the main problem is not getting a good launch. If I could hold it at the fuse I think things would be more successful . I balanced once at 18% and 20%.
The wing panels are still in good shape. So I am going to build a new fuse and make it into a tractor.
Then I should be able to get a decent launch .
The wing panels are still in good shape. So I am going to build a new fuse and make it into a tractor.
Then I should be able to get a decent launch .
10-08-2015, 11:19 AM
#55
You should be able to toss from holding the fuse the lift from the toss will have it raise up enough to clear your quickly downward moving hand 
I have also seen many high performance planes with pusher configs launched this way.
I have also seen many high performance planes with pusher configs launched this way.
10-08-2015, 11:32 AM
#56
Outside of the novelty of making a pusher design functional, I think you'll be happy with the choice to move the engine up front.
Judging from the amount of side area that your pusher design had in front of the CG...I didn't think just adding 2 inches to your winglets was going to safely offset the forward side area. Not a very scientific observation on my part, just a hunch based on a road I've traveled before.
Judging from the amount of side area that your pusher design had in front of the CG...I didn't think just adding 2 inches to your winglets was going to safely offset the forward side area. Not a very scientific observation on my part, just a hunch based on a road I've traveled before.
10-08-2015, 11:42 AM
#57
Thread Starter
Im still thinking about making another pusher sometime. Making the fuse so it could be held easy and provide some protection for my hand . The way its made now I didn't feel comforable about throwing it by the fuse.
10-08-2015, 12:28 PM
#58
If you could look at a slow motion replay of a overhand throwing launch, it would be interesting to see how close the prop comes to your hand.
The hand should be well clear of a 5 inch prop if your throwing motion has a good "follow through".
If you don't have a good hand hold from underneath the plane, then all bets are off.
The underhand toss is more clumsy IMO
The hand should be well clear of a 5 inch prop if your throwing motion has a good "follow through".
If you don't have a good hand hold from underneath the plane, then all bets are off.
The underhand toss is more clumsy IMO
10-08-2015, 01:44 PM
#59
Thread Starter
If you could look at a slow motion replay of a overhand throwing launch, it would be interesting to see how close the prop comes to your hand.
The hand should be well clear of a 5 inch prop if your throwing motion has a good "follow through".
If you don't have a good hand hold from underneath the plane, then all bets are off.
The underhand toss is more clumsy IMO
The hand should be well clear of a 5 inch prop if your throwing motion has a good "follow through".
If you don't have a good hand hold from underneath the plane, then all bets are off.
The underhand toss is more clumsy IMO
One guy in our club had a small foam electric pusher. He made a bad toss and it cost him 21stitches on his hand.
10-08-2015, 03:01 PM
#60
The first "pusher launches" I tried were while wearing a heavy leather welding glove. I was launching 4.2" to 5" diameter props, so the arc isn't as much [obviously] as a 6" prop would have been.
Without Instant Replay there is no way of knowing how close of a shave you are getting.
Without Instant Replay there is no way of knowing how close of a shave you are getting.
10-08-2015, 03:57 PM
#61
Lucky for this project it's a reed engine with torque low enough to just make you go ouch and perhaps a few dang its and such 
Any thin leather glove would be enough protection to avoid blood on the grass.
Any thin leather glove would be enough protection to avoid blood on the grass.
10-08-2015, 07:21 PM
#62
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Around 1992 I put an FP .15 on the back of a 32" canard with a Zinger 7-4 pusher. Flew great, but I never did launch it myself . My buddy bravely did many times and never did get nicked.. again who knows how close it was!
. My buddy bravely did many times and never did get nicked.. again who knows how close it was!
10-08-2015, 07:49 PM
#64
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It was one of these..
I acquired a "couple" of kits when I worked there. Mediocre rocket glider but fun prop plane/slope glider. And kewl looking. Flew decently with a BW pusher in the rear. With the .15, and flying at 6000' it was a bit hot.
I acquired a "couple" of kits when I worked there. Mediocre rocket glider but fun prop plane/slope glider. And kewl looking. Flew decently with a BW pusher in the rear. With the .15, and flying at 6000' it was a bit hot.
10-09-2015, 08:08 AM
#65
Before abandoning the pusher configuration, consider that moving the prop to the front may de-stabilize it. Searching back through history - it may be why designers added fins to the Northrop flying wing when switching from the pusher-props to jet engines.
Since you had a successful flight already, could you add a light ply, hand-hold spine to the belly to facilitate baseball style, hand launches?
Since you had a successful flight already, could you add a light ply, hand-hold spine to the belly to facilitate baseball style, hand launches?
10-09-2015, 12:08 PM
#67
Thread Starter
Before abandoning the pusher configuration, consider that moving the prop to the front may de-stabilize it. Searching back through history - it may be why designers added fins to the Northrop flying wing when switching from the pusher-props to jet engines.
Since you had a successful flight already, could you add a light ply, hand-hold spine to the belly to facilitate baseball style, hand launches?
Since you had a successful flight already, could you add a light ply, hand-hold spine to the belly to facilitate baseball style, hand launches?
I have already disassembled it. I was getting to frustrated with the crashes. Plus the fuse was getting torn up. Not sure I could have glued it up to many more times. I felt I had done about as much as I could and was time to try something else. There was also things about the way I made the fuse that I didn't like. Maybe with a tractor type it Will give me more insite on how to launch and the balance point .
I would still like to give the pusher a try again sometime.
Last edited by A. J. Clark; 10-09-2015 at 12:12 PM.
10-09-2015, 12:17 PM
#68
Thread Starter
10-09-2015, 01:29 PM
#69
www.youtube.com/watch?v=ebSlnlK8V5U This is the way for the Stryker. I have one, and got chicken with the holes provided for launching. I did a couple of launches that way with no issues though.
10-09-2015, 04:09 PM
#70
yea thats a light weight foamy with enough thrust to weight ratio to have a easy toss
Here's a bare chested German with no fear of launching with his hand on the underside
Take off at 1:10
https://www.youtube.com/watch?v=XlyYu4dcdJs
Here's a bare chested German with no fear of launching with his hand on the underside
Take off at 1:10
https://www.youtube.com/watch?v=XlyYu4dcdJs
12-03-2015, 07:22 AM
#71
Thread Starter
I've started to build a new fuse with the engine in the front. Want to see how it flies and find a good balance point. Would like to then go back to a rear engine.
12-03-2015, 10:58 AM
#72
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I guess you couldn't just start the engine CW and throw it backwards..
Hope it works out. Lots of people launch spinning pushers, I have and not hit yet, but I have no idea what the probability of getting sliced on the next launch may be and it always concerns me..
Hope it works out. Lots of people launch spinning pushers, I have and not hit yet, but I have no idea what the probability of getting sliced on the next launch may be and it always concerns me..
01-03-2016, 07:12 PM
#73
Thread Starter
Over the holidays I was able to finish the fuse for the tractor design. Came out at 10 oz. Might have to add some tail weight as it is a little nose heavy. I think it will be OK as is for the first test flight. Should have made the back of it another 3/8 to 1/2" longer. With the battery in the back could have moved it around for the right balance.
