Scale Avro Anson replica for memorial

Userofmuchtape&glue

Posted a thousand or more times
Hello chaps!

So to start with a bit of history:

During WW2, a Avro Anson crashed about 30kms from where I live. It was on a night navigation training flight for the RAAF, 4 people died in the crash.

So there is a man (Peter) who is a bit of a history nut and he wants to build a memorial with a plaque and a scale model of the Anson, between 40cm and a meter wingspan bit bigger is better.

He has asked me if I can make one, as I used to build wooden scale models.

I make have to make it out of steel to make it last, but if I can do it in wood I will!

So I am just wanting your thoughts on construction/materials and any random other stuff!

Abe

W2481
1 AD 12.9.41. 6 SFTS 1.11.41. 2 ANS 24.1.42. Crashed during night navigation training flight, 3 miles west of Noora, SA, 25.9.43. F/O Lawrence Andrew Flynn (pilot), P/O Albert Nicholas Rapp (Observer), Sgt John Vickery Bowman (Observer) and Sgt Ronald Edwin Obst (Observer) all killed.
 

rockyboy

Skill Collector
Mentor
That sounds like a very neat project! I haven't done any metal working in 30 years, but I remember how much fun brazing was as a technique to join all kinds of different materials from the junk yard together.
 

Geeto67

Posting Elsewhere
Sounds like an interesting project.

Honestly I wouldn't use "steel" as a memorial material. I would some form of bronze alloy, and cast it. Bronze is the most popular material for statutes and is fairly corrosion resistant and patinas fairly nicely over the years. I honestly wouldn't make any kind of lasting memorial out of wood since it just won't last.

If you are able to do home casting, you could probably make the thing yourself using the "lost wax" method or "Sandcasting" method of casting.

Lost wax means you make a form out of an easily melted material like wax or plastic, then build a fireproof casting mold around it, then heat the mold (or pour the liquid metal straight in) so the original form melts out of the mold.

Sandcasting means you take a form (like a wooden buck) and use it to make an imprint in casting sand. Then you remove the form and pour the molten metal into the sand cast. after it cools, you remove it and it destroys the mold, but you can always re-rake it and use the form to make another one.

What's nice about working with bronze and home casting is that you can break up the form into sections and then braze them together (welding with bronze rod) later on so you don't need to make a big mold.

Now, for the cool bit: if you have access to a 3d printer you can model the airplane in sections on the 3d printer, print out the sections and make the lost wax mold. I have had friends who have made small motorcycle parts this way, it works pretty well, and if you screw up the mold you can just print another piece and start over.

If you are committed to making a wood form first, then sandcasting is probably your best bet.

There are hundreds of home casting videos on youtube. watch a few and see if it is something you are up to. If not there are probably some local foundrys near you that may do statue casting and could take on the work if you create the form to work off of.

This is a very economical way of making a memorial.

Now, some things to consider:
If you are going to do it yourself, for the sake of weight you may want to figure out a way to cast it hallow. Most people will use gravity and make half piece molds and then join them later on.

If you have access to a plastic model kit of the airplane, it might not be a bad idea to copy the way they did the individual airframe components and then just assemble them with brazing later.
 

Userofmuchtape&glue

Posted a thousand or more times
Thank you all for your replies!

Rocky, I have not done any brazing my self but dad does a bit and I do enjoy soldering!

Geeto67, Wow, thanks! I am looking into bronze casting now, and it looks effective! We have decided if we are gonna bother to do it, we may as well make it worth while and big!
Maybe I could do a composite model, with bronze molded outer parts. how clean of a braze joint could you get? would it be like a weld seam?

Hai-lee, thanks for those! I had found a set of plans similar on aerofred, and I may still use them.

I will let you know how I go and of any progress.

Abe
 

Geeto67

Posting Elsewhere
Thank you all for your replies!

Rocky, I have not done any brazing my self but dad does a bit and I do enjoy soldering!

Geeto67, Wow, thanks! I am looking into bronze casting now, and it looks effective! We have decided if we are gonna bother to do it, we may as well make it worth while and big!
Maybe I could do a composite model, with bronze molded outer parts. how clean of a braze joint could you get? would it be like a weld seam?

Hai-lee, thanks for those! I had found a set of plans similar on aerofred, and I may still use them.

I will let you know how I go and of any progress.

Abe


Regarding the brazed joints, when you build the statue in sections you would want to pin it - have pins on one piece that fit into holes on the other piece. This will help align and take the stress of supporting the weight of the pieces off the brazed joint. Once the weld no longer has to support the weight, you could grind it flush so it is invisible, otherwise it will look like a welded seam. Now there are other ways around that like if you use a lap joint to fit the pieces together you can drill a hole on the outer piece over where the lap is and then fill the hole with molten bronze and that will hold the pieces together leaving only the joint to look like a panel line.

Brazing is just like oxy or tig welding except you are using a silicon bronze wire and lower temperatures. I think there are even spools available for mig welders of the same wire. Personally I have only done it with an oxy torch (i used to build and repair car radiators as a kid in college) but it isn’t hard. As long as you pay attention to what you are doing you should be fine.