<< Previous Topic | Next Topic >>Return to Index  

Question about Spitfire propellers

October 7 2010 at 11:44 AM
John Maher  (Login wjmaher)
HyperScale Forums
from IP address 76.66.216.58

I understand that many of these props where made of a wood composite. Is this the "Jablo" blade?

I also understand that the coloured disc at the base of the prop indicates whether the blade was wooden or metal. Does anyone know if the rusty red disc meant a wooden blade?

Also, anyone know of a photograph of the wooden blades before they were painted?

I did try a Google search but no joy.

 
 Respond to this message   
AuthorReply
Robert Swaddling
(Login N521R)
HyperScale Forums
74.12.177.28

Jablo is wood

October 7 2010, 12:13 PM 

Hi John
Jablo blades are wood composite and were made by Rotol. The rusty red disc is the manufacturer's logo. I have a Jablo blade at my shop if you would like to see one. I also have a sawn off portion of a Jablo blade so that one can see how the wood was put together.
Cheers
Bob Swaddling

 
 Respond to this message   

Jon Kunac-Tabinor
(Login JonTabinor)
HyperScale Forums
92.14.182.19

HI Bob - interesting!

October 7 2010, 1:54 PM 

was the Jablo blade made from laminations or was it a some kind of wood pulp and resin mix? always wondered?

cheers

Jonners


A mighty wind is blowing, blowing you, blowing me.....


 
 Respond to this message   
Robert Swaddling
(Login N521R)
HyperScale Forums
74.12.177.28

Inside pic of jablo blade

October 7 2010, 2:04 PM 

Hi Jon
Here is a pic of the inside of a shattered jablo blade showing how it is built up and the thin veneer that covers it. It is all a very specialized process and very expensive today. The leading edge is thin brass. This is the trailing edge.

[linked image]

I also have a complete wartime blade off of MK923 (5J-Z).

Cheers
Bob Swaddling


    
This message has been edited by N521R from IP address 74.12.177.28 on Oct 7, 2010 2:05 PM


 
 Respond to this message   
John Maher
(Login wjmaher)
HyperScale Forums
70.28.105.131

Thanks Bob, very interesting...

October 7 2010, 2:42 PM 

So if one wanted to replicate the rear of the prop blades as worn down to the original surface (commonly seen on all propellers if they're used long enough), you'd create a wooden laminate finish first?

And I was surprised to see the leading edges are brass: the chipping seen in photographs on the blades seems to be silver not brass.

Where is your shop?

 
 Respond to this message   
Edgar Brooks
(Login Edgar.Brooks)
HyperScale Forums
82.13.139.135

Props would not be allowed to wear down to the wood. Rotol made Jablo, Hydulignum and

October 7 2010, 3:03 PM 

Weybridge Wood blades, all of which had a plastic covering over the wood. Wear tended to be at the front, and increased towards the tip, with the semi-matt black finish becoming dull, then possibly showing the brass l/e sheath. The blades were normally made under huge pressure, while gluing, which reduced the wood to about half its original thickness; after shaping, and sheathing, it was coated with a plastic "Rotoloid," "Rayoid," or "Schwarz" covering. Rotol's coloured disc was, according to them, pink, not rust, or could be yellow. Pink = Rotol wood, yellow = spruce or Douglas Fir, and the circle usually included further information, with two letters denoting the make-up of the blade, then a single letter signifying balance (3 or 4 blades, with the same letter, could be safely used on the same prop,) followed by a 4-figure serial no. Above the disc should be a set of yellow letters & figures, which gives the drawing no.

 
 Respond to this message   
John Maher
(Login wjmaher)
HyperScale Forums
76.65.29.108

Thanks Edgar, as always very informative

October 7 2010, 6:08 PM 


 
 Respond to this message   
Robert Swaddling
(Login N521R)
HyperScale Forums
74.12.177.28

That is great info.

October 7 2010, 6:40 PM 

Hi Edgar
I never new about "Rotoloid" being plastic. I didn't want to go digging on my Rotol blade off of MK923. I always wondered what the veneer was.
Cheers
Bob Swaddling

 
 Respond to this message   
Robert Swaddling
(Login N521R)
HyperScale Forums
74.12.177.28

Worn Rotol blades

October 7 2010, 6:35 PM 

Hi John
Yes the leading edge is brass and so if it got nicked you would see brass not silver. The one in my hobby shop is nicked up pretty good and you can see the brass but no wood shows.
My shop is Action Hobbies Kingsville and it is in Kingsville Ontario Canada. Right now I am home convelesing but would go in if you let me know you are coming in. >

Cheers
Bob Swaddling

 
 Respond to this message   
John Maher
(Login wjmaher)
HyperScale Forums
76.65.29.108

Thanks for the offer Bob,...

October 7 2010, 10:23 PM 

Are you near the Russell Group?

 
 Respond to this message   
Robert Swaddling
(Login N521R)
HyperScale Forums
74.12.177.28

Russell group is about 4 hrs east.

October 7 2010, 10:35 PM 


 
 Respond to this message   
jcf
(Login Jon_Farrelly)
HyperScale Forums
71.197.185.59

ROTOL Jablo, Hydulignum and Weybridge wooden blades ...

October 7 2010, 6:48 PM 

[linked image]

[linked image]

[linked image]

From the ROTOL section of the propeller reference pages on the AEHS site:

http://www.enginehistory.org/Propellers/Rotol/rotol.htm

Ideas are as cheap as blackberries! - Prof. Hugo Junkers

 
 Respond to this message   
Robert Swaddling
(Login N521R)
HyperScale Forums
74.12.177.28

This is fantastic information. Thank you Jon. n/t

October 7 2010, 8:54 PM 


 
 Respond to this message   
 
  << Previous Topic | Next Topic >>Return to Index  

Posting or replying to messages on Plane Talking requires visitors to register:

  1. First you will need to register with Network 54, the Forum provider. Click here to register with Network 54. (If you already have a Network 54 Login you can go straight to the next step)
  2. Then, while signed in to Network 54, you can sign up for HyperScale's forums. Click here to sign up for HyperScale's forums.

Your user name and password will give you full posting privileges to all of HyperScale Forums.

Please note the following conditions of posting:

All contributions are welcome but please refrain from political or abusive comments, racially or religiously offensive remarks, swearing (including the thin disguising of swear words with asterisks and other characters), insulting language and crude metaphors. Please do not use Plane Talking as a public platform to complain about retailers or manufacturers (about issues such as broken or missing parts) before you have followed all normal channels to resolve any greivance. Plane Talking is not the place to conduct personal feuds or for posting personal attacks. Please do not post in capital letters only, as this is considered to be shouting and therefore impolite. Also, please do not post in 'texting message' word format. Any posts breaching these guidelines will promptly be removed from the server and the offender may be excluded from further posting to the HyperScale Forums. Off-topic posts may also be removed from the server.

In addition, Plane Talking is not a forum for the public criticism of the models that appear as Galleries or Articles. Please make any suggestions for improvements or criticism direct to the author via the email link at the bottom of the Article.

Finally, please note that this Discussion Group is privately operated and that I reserve the right to delete any post or cancel any registration for any reason whatsoever.

free counters