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Can a Tee See 049 spin a 1.5" spinner
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Can a Tee See 049 spin a 1.5" spinner
Does anybody know or ever tried using an RC type plastic 1.50" plastic spinner on a TD 049? Will the engine tolerate it? Or will the power loss be too much? Thanks.
kevin king- Silver Member
- Posts : 95
Join date : 2020-04-16
Re: Can a Tee See 049 spin a 1.5" spinner
Well, I’ve used a 1¼” on a TD, so why not?
The TC Mark
The TC Mark
batjac- Diamond Member
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Posts : 2332
Join date : 2013-05-22
Age : 60
Location : Broken Arrow, OK, USA
Re: Can a Tee See 049 spin a 1.5" spinner
It will do it. Far from ideal though. How much does the spinner weigh?
I am horrible with math, but seems to me the weight would have more effect the further out it goes from the crank centerline.
I am horrible with math, but seems to me the weight would have more effect the further out it goes from the crank centerline.
Cribbs74- Moderator
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Posts : 11892
Join date : 2011-10-24
Age : 50
Location : Tuttle, OK
Re: Can a Tee See 049 spin a 1.5" spinner
Sure it will spin it. But how fast? Who knows? Might be adequate depending on your mission. If you're a speed demon, forget it. Try it out and let us know.
Tee Bee- Platinum Member
- Posts : 763
Join date : 2011-08-25
Location : Angleton, TX
Re: Can a Tee See 049 spin a 1.5" spinner
Might be a dumb question (still an honest one) but why would a spinner reduce the rpm?
If we assume it is balanced well enough, and not remarkably heavy, all I can think of is a minor flywheel effect that it may cause. Also some drag while flying obviously but a spinner is more aerodynamic than a bare engine without a spinner. A large spinner obviously covers part of the propeller blades but that should increase the rpm somewhat, right
Any input from the experts would be most welcome
If we assume it is balanced well enough, and not remarkably heavy, all I can think of is a minor flywheel effect that it may cause. Also some drag while flying obviously but a spinner is more aerodynamic than a bare engine without a spinner. A large spinner obviously covers part of the propeller blades but that should increase the rpm somewhat, right
Any input from the experts would be most welcome
KariFS- Diamond Member
- Posts : 1993
Join date : 2014-10-10
Age : 52
Re: Can a Tee See 049 spin a 1.5" spinner
KariFS wrote:Might be a dumb question (still an honest one) but why would a spinner reduce the rpm?
If we assume it is balanced well enough, and not remarkably heavy, all I can think of is a minor flywheel effect that it may cause. Also some drag while flying obviously but a spinner is more aerodynamic than a bare engine without a spinner. A large spinner obviously covers part of the propeller blades but that should increase the rpm somewhat, right
Any input from the experts would be most welcome
Yes, my thoughts as well!
Oldenginerod- Top Poster
- Posts : 3962
Join date : 2012-06-15
Age : 61
Location : Drouin, Victoria
Re: Can a Tee See 049 spin a 1.5" spinner
I guess I should have been more specific. The larger spinner will blank out some of the prop, therefore possibly reducing some thrust with a resultant lower forward speed. As I mentioned, if speed isn’t a factor, it might work out just fine.
Tee Bee- Platinum Member
- Posts : 763
Join date : 2011-08-25
Location : Angleton, TX
Re: Can a Tee See 049 spin a 1.5" spinner
With Cox .010, .020 thru .051
additional heat
vibrations
ball socket wear
wear on the aluminum crankcase / slop over time
oversized cutouts for the blades will cause load
This is the only plastic spinner I would use with a Cox Reed .049, has proper cut outs with the right prop.
Fantastic low weight good fit opportunity:
I would like to have small cut outs to custom fit the selected prop. The stud to be made
out of proper grade aluminum with plenty of threads to save weight out on the end of the crank.
Options for black and red / white shows dirt so just two other primary colors would be a plus.
additional heat
vibrations
ball socket wear
wear on the aluminum crankcase / slop over time
oversized cutouts for the blades will cause load
This is the only plastic spinner I would use with a Cox Reed .049, has proper cut outs with the right prop.
Fantastic low weight good fit opportunity:
I would like to have small cut outs to custom fit the selected prop. The stud to be made
out of proper grade aluminum with plenty of threads to save weight out on the end of the crank.
Options for black and red / white shows dirt so just two other primary colors would be a plus.
1/2A Nut- Top Poster
- Posts : 3402
Join date : 2013-10-20
Age : 60
Location : Brad in Texas
Re: Can a Tee See 049 spin a 1.5" spinner
Thanks Tee Bee and ’Nut for your answers! I was thinking ”power = rpm”, but it is not that straightforward obviously. Thrust is what makes airplanes go, not rpm
KariFS- Diamond Member
- Posts : 1993
Join date : 2014-10-10
Age : 52
Re: Can a Tee See 049 spin a 1.5" spinner
Perhaps the reason for misunderstanding engine loading is the load variance while running is difficult to visualize? An IC engine actually has a power stroke and an exhaust stroke where the power (combustion) stroke accelerates the piston but the exhaust (pumping) stroke slows it down. A spinner or flywheel will load the engine (no matter how little) and cause a small loss of power.
I think we tend to forget this because they sound more like a turbine than a tiny IC engine.
I never entered a model contest where speed or aerobatics was a goal but did use a few spinners on really hard to start engines so a starter could be used. Found out early on that plastic spinners were not up to the task.
Bill
I think we tend to forget this because they sound more like a turbine than a tiny IC engine.
I never entered a model contest where speed or aerobatics was a goal but did use a few spinners on really hard to start engines so a starter could be used. Found out early on that plastic spinners were not up to the task.
Bill
smooth_bill- Gold Member
- Posts : 229
Join date : 2012-02-19
Age : 86
Location : Beaverton, OR
Re: Can a Tee See 049 spin a 1.5" spinner
A spinner will have minimal impact on thrust. The center of the prop is particularly draggy, so a spinner will likely improve speed, but this really depends on the rest of the airframe. The outer 1/3 of the prop blade does 90% of the work.
The biggest issue with a large spinner on a small engine is getting it installed so it runs true and has the balance needed to run as fast as they do.
20 years ago I was flying electric racers with 4.75"-5" props in a 1.5" spinner at ~30+kRPM on a motor with a 1/8" shaft and it went over 150MPH.
The biggest issue with a large spinner on a small engine is getting it installed so it runs true and has the balance needed to run as fast as they do.
20 years ago I was flying electric racers with 4.75"-5" props in a 1.5" spinner at ~30+kRPM on a motor with a 1/8" shaft and it went over 150MPH.
gkamysz- Gold Member
- Posts : 375
Join date : 2018-02-22
Location : Chicagoland
Re: Can a Tee See 049 spin a 1.5" spinner
Thanks for the input gentlemen. I think I will revamp the plane around the yellow Cox spinner. The plane will be smaller and lighter.
Last edited by kevin king on Tue Sep 29, 2020 10:03 pm; edited 1 time in total
kevin king- Silver Member
- Posts : 95
Join date : 2020-04-16
Re: Can a Tee See 049 spin a 1.5" spinner
Just so you know, the outside 10% of the prop puts out the majority of the thrust. That's why planes with big radial cowls don't suffer much, and also why larger spinners don't take away any significant amount of thrust.
badbill- Gold Member
- Posts : 312
Join date : 2015-08-13
Age : 67
Location : Centerville, Georgia
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