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[Antonie RossouwParticipant @antonierossouw30197]

Telstar,
Can you maybe tell how to create my own brass props for my next boat.Here in South Africa we pay an arm and a leg for model boat parts….
Thanks
Antonie

[Sandy ThomsonParticipant @sandythomson]

Hi Antonie,

 On a recent visit to Cape Town, I visited their maritime museum at the waterfront and in it was a simple jig for holding propeller blades whilst soldering on to the hub, for model boats.

Unfortunately they would not let me photograph this jig and I have not been able to copy it properly.

                                                  A.T.

[Antonie RossouwParticipant @antonierossouw30197]

Alex,

Thanks,I think I can fabricate some "device"for that.I am new to boat building but eager to learn

[Len OchiltreeParticipant @lenochiltree67043]

Hi Antonie,

Have alook at Bob Abells "Great Eastern" in his Gallery,he shows his home made prop.

Len,

[TelstarParticipant @telstar]

Hi Antonie,

I apologise for not responding sooner, I visited Alexander palace model show, so was incommunicado for a while.

I fabricate the props, as opposed to casting etc. turning the boss in a small lathe and soldering on the blades.   I dont make high speed props only scale type,  and these are freelance (ie I make them to ‘look right’ not strictly to drawings etc.) .

The more I think about making a prop the more I realise its not as simple as I thought.

What I can do if you wish, is write down some of the steps, and maybe a sketch or two of the process.

I’ve posted a photo of a pair of props waiting to be finished

Cheers Tom

ps Alex  T    Sandy perhaps I could pick your brain to improve my methods, as of old

[Sandy ThomsonParticipant @sandythomson]

Telstar,

like you I turn the boss out in a small lathe.  I tap out one end 2 or 4BA (not yet metric!) remove, screw on to a 2BA/4BA bolt which is in the chuck,and then shape the boss. I now have a form tool, but I used to just use a file.

I then screw the boss on to a vertical stud on a jig I made to hold three blades in the position I want. I should add that the boss by this time has three diagonal saw cuts to take the blades whilst I solder. My first attempts were soft solder but now I use silver solder.

The blades are cut roughly out of brass sheet of the thickness of a hacksaw blade. Can be junior or full blade depending on the size of prop or boss.

I soft solder three blades together, cut them to shape, desolder and I have three identical blades. The description of my jig is a bit complicated but those propellers do work.  By twisting the end of each blade you vary the pitch to suit.           A.T.

[TelstarParticipant @telstar]

Sandy

Youv’e described the process to a tee. I still have BA taps but I got up to date when I left Tyneside. I tend to use hot glue to hold the blades together to file to shape.

I have a jig that I mount in the toolpost of the lathe to guide the saw when cutting the slots ( the boss still mounted in the chuck) to get the correct angle, or at least the same angle.   Like you I use silver solder, then remount the prop in the lathe chuck to twist the blades with a template in the toolholder to help me get each twist the same.

I suppose its no suprise we both use similar methods, since Bill Carpenter taught both of us?

Tommy D aka Telstar

[Bob Abell 2Participant @bobabell2]

Just posted a closeup of prop for Great Eastern……..Brass ends will be added shortly to make a spherical boss……………mounted on a 2BA shaft

[Sandy ThomsonParticipant @sandythomson]

Telstar

You got it wrong it the wrong way around,  I taught Bill Carpenter. A.T.

[Antonie RossouwParticipant @antonierossouw30197]

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