22 Set on Handcart

[cletrac (RIP)]

I blew up the picture and you can tell it's soldered copper pipes (probably 3/4")
The tires would be 16" OD.
The text and cart pictures are off a D-Day site.
The manual is for a No1 MkIII and these pics are NoI MKIV.

[Chris Suslowicz]

I've seen a real one, and I think it's 1" or larger steel tube.

(If they were copper the scrap dealers would have ensured that every single one would have been traced and melted down by now.)

I'm fairly sure the museum of technology in Milton Keynes (UK) has got an original.
Must have a visit some time.

(Apparently the tyres are an odd size and "difficult"; you have been warned.)

:-)>

[cletrac (RIP)]

Chris, in that closeup it's definitely soldered together and by someone who wasn't very good at it. You wouldn't even try to use solder with steel pipes. And where would you get those fittings in steel?
I blew up another of those pics and that plug for the microphone has a 1" diameter end. It's the same size as the outside of the fittings and 3/4" copper fittings are 1" outside diameter.

[Ron Pier]

I have no intention of building one of these carts, but I am intrigued now as to how they were built. Did they actually have our everyday copper plumbing fittings back then? My personal guess is that the fittings were cast or forged in steel and the whole thing brazed together with steel tube, as per a motorcycle frame. No need to clean up the braze splatter on such a utilitarian item. We won't know for sure of course until one of us sees a real one.
Likewise I'd like to no the tyre size. I'd guess they are 19" wheels and maybe the same size tyres as a Flea which are hard to find 2.75 x 19????

Ron

[cletrac (RIP)]

I used Photoshop and cropped the picture to the size of the image. Then I made it 10 inches long and printed it. The cart is now 1/8" to the inch.
I took front and rear measurements and averaged them to allow for perspective.
The wheels are 12" diameter.
The tire OD is 15"
From the ground to the equipment tray is 21"
The handles stick out 16 1/2 inches and are 7 1/2" deep.
The pipes are just over 3/4"

[Ron Pier]

Ah yes. Silly me. I can clearly see that the wheels are much smaller than 19".
I did some scaling myself from this picture and came up with just over 15" for the tyre. Ron

[Chris Suslowicz]

Originally Posted by cletrac

Chris, in that closeup it's definitely soldered together and by someone who wasn't very good at it. You wouldn't even try to use solder with steel pipes. And where would you get those fittings in steel?
I blew up another of those pics and that plug for the microphone has a 1" diameter end. It's the same size as the outside of the fittings and 3/4" copper fittings are 1" outside diameter.

Unless it's a prototype I cannot imagine them using copper tube. It would be too soft and also copper was in short supply.

My guess is that it's 3/4" or 1" steel conduit, which has fittings that look very much like the ones pictured, and they may have soldered the joints later to prevent things working loose.

It could also be brazed or even gas welded.

We need to find an original and test it with a magnet. :-)>

Chris.

[cletrac (RIP)]

In that picture of the joints it's definitely solder.
Brazing will never look like that.
In 4 feet you've got 4 uprights so strength wouldn't be an issue.
That could be a prototype or maybe they wanted copper's corrosion resistance.
12" x 1 1/2" or 12" x 2" are common bike sizes.

[Bruce Parker (RIP)]

Originally Posted by cletrac

In that picture of the joints it's definitely solder.
Brazing will never look like that.
In 4 feet you've got 4 uprights so strength wouldn't be an issue.
That could be a prototype or maybe they wanted copper's corrosion resistance.
12" x 1 1/2" or 12" x 2" are common bike sizes.

Grounded copper to minimize radio interference that a steel cage might cause?

[cletrac (RIP)]

Bruce, stopping interference makes sense. So when does the project get underway? I see 3/4" copper tees on ebay for under a buck apiece.

[jack neville]

Originally Posted by cletrac

In that picture of the joints it's definitely solder.
Brazing will never look like that.
In 4 feet you've got 4 uprights so strength wouldn't be an issue.
That could be a prototype or maybe they wanted copper's corrosion resistance.
12" x 1 1/2" or 12" x 2" are common bike sizes.

Have you looked at the brazing on BSA airborne bicycles? There is plenty of evidence of sloppy brazing on the two bicycles I have. Maybe these frames were produced in a similar fashion.

[Ron Pier]

[QUOTE=cletrac;
12" x 1 1/2" or 12" x 2" are common bike sizes.[/QUOTE]

The tyre size on my Welbike is 12 1/2" x 2 1/4" but the wheel is only 8" diam.
These cycle tyres seem to quote the outer diam of the tyre. So you are probably looking for 15" tyres on 12" wheels? Ron

[Bruce MacMillan]

Here's another one that was listed for sale on Milweb.

http://www.milweb.net/webverts/54385/f.jpg

Looking at the T joints they appear to have ribbing on the ends and rivets like you get with steel, not copper. I agree with Chris in that I think copper would be too soft. Consider the weight of the set, accessories and batteries and having that bounce up and down.

Tyres are different so I wonder if these were made by a manufacturer or local REME which could account for differences.