Need help choosing props.
#1
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From: Las Vegas, NV
I have alot of warbirds, and alot of saito engines. I have been flying my H9 Hellcat w/ Saito 100 and a 14x8 graupner 3 blade.
Will this combination work well w/ my other warbirds? p-47, f4-u, zero, p-40, etc...
I also have a kmp p-38 w/ two saito 125's what 3 blade can I use?
thanks, Jack Pitre
Will this combination work well w/ my other warbirds? p-47, f4-u, zero, p-40, etc...
I also have a kmp p-38 w/ two saito 125's what 3 blade can I use?
thanks, Jack Pitre
#2

Hi!
No 3-blade prop can compare to good 2-blade! Small 14x8 3-blade props doesn't look scale at all anyway on a fighter.
I would try a 16x6 -16x7 APC or Graupner Cam prop on the 1.25 saito....Or a wood prop filed and sanded correctly so that it gives good performance
Regards!
Jan K
No 3-blade prop can compare to good 2-blade! Small 14x8 3-blade props doesn't look scale at all anyway on a fighter.
I would try a 16x6 -16x7 APC or Graupner Cam prop on the 1.25 saito....Or a wood prop filed and sanded correctly so that it gives good performance
Regards!
Jan K
#3
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From: Las Vegas, NV
Graupner does not make a 14x8 three blade prop.The Graupner 14x7 is a perfect match for the Saito 100. I have them on all of my Hangar 9 warbirds. I would use a 15x8 or a 16x8 three balde with the Saito 125.
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From: Fairfax,
VA
I beleive the rule is to drop one inch in dia if you add a third blade. IMHO 3 blades are neat but you don't get much for the price. I do want to use one on my Saito 450 though. I beleive the Saito 100 likes a 15x6 which would mean using a 14x6 3 blade. I would test and check with a tach. If it loads the motor enough that you are getting less than 8k I would not use it. Notice that each brand of prop will give different results. I used a APC 17x8 on my Saito 180 and it was happy, following the "rule" a 16x8 should give about 8.3k. Personally I like the pull of large dia props and use the pitch for adjusting speed within reason.
Carl
Carl
#7
For the same prop load you need to drop one inch of diam and pitch. The biggest prop you can run on a 125 is a 16/8 but a 15/8 would be a better choice allowing the engine to run in the low 9's and making better use of the engines powerband. That would translate into 14/7 3 blade being your best choice. I would recomend using a 2 bladed prop for flying as it would perform better. The three bladed props you can run on these engines are not even close to being scale and look just as stupid as 2 bladed props, so why not use the combination that works better ie a Saito 125 with 2 bladed APC 15/8.
#9

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jack , obviuosly two big advantages to three blades -straight from the manufacturer
1)more ground clearance
2)less vibration
I have seen 4 differant websites when asking for prop suggestions , they all have differant data -not extremely differant but differant
I like the www.radicalworks.com propeller because they give you a starting prop -then suggest alterative props .
so for example -for a 4 stroke -2 bladed prop .90 size engine the range is
14/6 to start
then 13/6 14/8 15/6 16/6 is the range based on plane and RPMs -all listed on the site
1)more ground clearance
2)less vibration
I have seen 4 differant websites when asking for prop suggestions , they all have differant data -not extremely differant but differant
I like the www.radicalworks.com propeller because they give you a starting prop -then suggest alterative props .
so for example -for a 4 stroke -2 bladed prop .90 size engine the range is
14/6 to start
then 13/6 14/8 15/6 16/6 is the range based on plane and RPMs -all listed on the site



