Prop question

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Prop question

Postby birdbuster » Sat Mar 30, 2013 3:56 pm

:?: Do any of y'all know if a four bladed prop would work better than a two bladed prop :?:
bb
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Re: Prop question

Postby Mitch » Sat Mar 30, 2013 5:11 pm

I do not know but I would check this out...

http://www.samsmodels.com/acatalog/Sect ... llors.html

When you click on that link...scroll down to see the props I'm talking about!
If they don't work better, they sure would look better... Has 3 different center hubs for 2, 3, or 4 blade configuration...
I was planning on buying these for my WW2 birds, but don't want to change to much just before the WESTFAC Event... try them out and let us know!
They look like they are made for electric I do not know?

:D Mitch
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Re: Prop question

Postby birdbuster » Sat Mar 30, 2013 6:04 pm

I think what I'll do is just put two of the guillow's 5-inch props together,since the other ones are in England.(This will be for a bird-dog).
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Re: Prop question

Postby Steve Blanchard » Tue Apr 02, 2013 10:42 am

birdbuster,

Four bladed props for the most part are not as efficient as two bladed props for rubber power. As a matter of fact some of the older designs called for single bladed props. Sounds strange but they work very well. I would stick with the two bladed props at this point. I would ditch the Guillow's prop that came with the kit in favor of either a Peck polymers silver prop or one of the Czech props available from A to Z online store.

Steve
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Re: Prop question

Postby Mitch » Thu Apr 04, 2013 10:04 am

Hey Guys here's another prop question...

I am planning on ordering some more props... getting those Silver ones from Peck, 7, 8, and 9.5 inches.
I have been looking at some pics on the net and see that props are sometimes quite large.
Last year I test flew my 400 Mustang with a Black 9 inch prop and it flew worse thane the kits 7 inch.
Maybe 9 was too much? Or maybe not balanced?
I think FAC rules are 1/3 ws is maximum, so 9.5 should work for 30 inch ws model.
I plan to test my planes with 8 inch to get more performance... What do you think?

Also ordering more Tan rubber... getting my supplies for WEST FAC... Mitch :D
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Re: Prop question

Postby Charles_c » Thu Apr 04, 2013 10:25 am

I made a four bladed prop out of two of the Guillow's famous red props, for my Spitfire Mk-Vb Floatplane. It's not a flyer, but the prop will pull the bird across the pool with about 150 turns on the prop. I just drew the shape of the prop, carved it down, notched both and glued them together. I used a single hole punch to make the holes in the spinner and it all worked out just fine.

Charles
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Real Airplanes Have Round Engines and Two Wings !
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Re: Prop question

Postby Charles_c » Thu Apr 04, 2013 10:27 am

Here's my Spitfire Mk-Vb floatplane showing the four bladed prop. Thew floats were copied from Guillow's "Rufe" and the float pylons just scratchbuilt from solid balsa.

Charles
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Re: Prop question

Postby Steve Blanchard » Thu Apr 04, 2013 2:50 pm

Hey Mitch,

There are no maximum prop rules in FAC for scale models. There might be for some old timer events but I'm not sure. 1/3 the WS is suggested as a starting point and usually is a good rule of thumb. I would suggest the Peck silver props in all sizes. For the 400 series I would either use the 8" or the 9" depending on the model. The things that help determine this are Weight, type of model as in how much drag (Biplanes have more drag and I usually go for a slightly larger prop). The larger the prop the more the rubber. It's a balancing act between all of those factors. I do use the Peck silver props quite a bit and found they work really well for me. I have carved props, built them from sour cream containers or laminated blades from Ply or Balsa. It all depends on what you need and as you go along you will be able determine what you need before you even start the model.

Good luck!

Steve
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Re: Prop question

Postby Phugoid » Thu Apr 04, 2013 3:21 pm

The silver peck props are ok, but I have tended to have better luck with the Czech Igra props. They tend to have more blade area for the diameter and a slightly more aggressive pitch. They are pretty well much the same as the old Tern aero prop but with a much stronger clutch. Aside from that they tend to be much much better balanced from the get go, the last few peck ones I've had have needed some serious scraping to get them anywhere near balance.

Andrew
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Re: Prop question

Postby Phugoid » Thu Apr 04, 2013 3:23 pm

Ps super spit BTW!

Andrew
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Re: Prop question

Postby Mitch » Wed Apr 10, 2013 9:55 pm

Mails In... Got some new props today...The Silver Ones, from Peck.
Image
7, 8, 9-1/2 inches. Black ones are Guillows supplied 7 and 9 inch.

Plan to increase to the Silver 8 inch for my WW2 fliers (400 series)

Planning 8, but may go to the 9-1/2 for the SE5a
If the Eindecker is ready, that will take the 9-1/2 as well.

I am impressed with the pitch to the props, seem more than the Black ones. I will spend some time cleaning the flash and balancing.

Also got 3/16 and 1/8 inch FAI Supper Sport Rubber...

Anything else I should get ready for... I have the rubber lube and I will exercise the rubber motors before extreme winding...

Mitch...
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