Algebra build thread

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Cliff Evans
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Re: Algebra build thread

Post by Cliff Evans » 10 May 2018, 22:03

Well done Peter. Looks great!

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Trevor
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Re: Algebra build thread

Post by Trevor » 11 May 2018, 07:58

Congratulations. A fitting conclusion to the project.

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Peter Balcombe
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Re: Algebra build thread

Post by Peter Balcombe » 06 Aug 2018, 11:17

A couple more photos in better conditions, courtesy of Andy Davey.
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Algebra_31Jul18_1_crop.jpg

AndyWarlow
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Re: Algebra build thread

Post by AndyWarlow » 20 Sep 2018, 16:53

Hi Peter,
I have just purchased an Algebra kit from Cliff and am trying to work out the various additional bits I now need before commencing the build. One area that I am struggling with are the brass wing joiner tubes and ballast tube as the holes in the wing ribs are obviously cut to a specific outside diameter. Can you help me by telling me where you obtained the tubes for your build. Thanks. Andy

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Peter Balcombe
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Re: Algebra build thread

Post by Peter Balcombe » 20 Sep 2018, 18:14

Andy,
The joiners are 6swg piano wire/6swg I.D. brass tubes & the ballast tube is 1/2” O.D. aluminium tube.
This info. is labelled on the plan between the root end of the wing & the R1 cross section.
Note that the tubes are parallel to the wing surface as the two joiner rods are bent to give the required dihedral angle of just over 2 degrees each side.
Although not shown on the wing plan, my joiner rods were both identical, each being 240mm long and bent in the centre until the lower edge of one end was 10mm above the lower edge of the other section.
Note that this is less than for the original Sean Bannister design due to the aileron wing.

The tailplane is attached as per the Sean Bannister design using an AMT crank with 14swg piano wire & brass tubes.

You should be able to find the materials at any good model shop, else try an online shop such as Sussex Model Centre.

Note that if you use the ballast tube then you would need to make up suitable lead slugs/spacers or or similar to suit the I.D. of the ballast tubes. I have not yet done this. The ballast tube size is as per the Sean Bannister design.
Hope this helps.
Peter

AndyWarlow
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Re: Algebra build thread

Post by AndyWarlow » 20 Sep 2018, 18:27

Hi Peter,

Thank you for the info. I had worked out the tubes/joiners etc from the plan but wasn't sure if I could buy my 6swg tubes from any supplier and they would still fit the holes cut in the wing ribs or whether tubes from one supplier worked better. As I need to order materials from the Balsa Cabin I will also get the rods and tubes from them and see how I get on.

When you say that 'the lower edge of one end was 10mm above the lower edge of the other section' I take this to mean that when laid flat, with the bend in the middle, one end is now 10mm above the flat surface. Have I understood you correctly?

Regards
Andy

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Peter Balcombe
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Re: Algebra build thread

Post by Peter Balcombe » 20 Sep 2018, 18:41

Andy,
Yes the joiner tubes are bog standard 6swg brass tube & the rib holes are sized to suit.
I was able to slide the tubes straight into the assembled rib structure without any trouble.
Yes, having one end of the wire angle flat on the bench & looking for the lower surface of the other end being 10mm above the bench would work equally well.
I bent one joiner to correct angle & then made the 2nd to be exactly the same when placed together flat on the bench.
As long as both wires are bent to the same angle, the exact angle is not so critical.

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Peter Balcombe
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Re: Algebra build thread

Post by Peter Balcombe » 22 Sep 2018, 21:47

Andy,
The 1/2” Aluminium tube is K&S part No. 83035.
I cannot recall where I got mine from, but see it listed both on eBay and on the Elite Models website at about £4.50 per 12” length.
Even if you don’t intend to use ballast, it might be worth installing the tubes as they will add strength to the wing root area.
Peter

Martin G
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Re: Algebra build thread

Post by Martin G » 22 Sep 2018, 23:17

My original 100S Algebra had 18" ballast tubes if I remember correctly.
I was lucky enough to get hold of some offcuts of titanium tube from the scrap bin at work. Those wings were strong!

AndyWarlow
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Re: Algebra build thread

Post by AndyWarlow » 23 Sep 2018, 16:26

Peter,
I have now ordered balsa, piano wire and joiner tubes from Balsa Cabin. The aluminium tube is coming from an engineering company and servos have already arrived so once the balsa makes an appearance I am ready to build and will start a new build thread. Thanks for your help to date. Andy

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