1911 2 3/4 Restoration - Plated Carburettor

[Chris54]

Hi All, I am new to Douglas and this forum, we, my friend Tony and I are restoring two 1911 2 3/4 hp model D.
We have one bike about 80% complete, just have to make a fuel tank now, complete with all The fittings, if any drawings of the fittings are available this would help, up until now we have been measuring parts on other bikes to make parts, seems to have worked along with copying the original parts we have, for the second bike, Oh the second bike, not so much of a restoration as a complete build, the frame and wheels are mostly missing, we really need to find another frame and wheels, anyone out there know of their whereabouts ?
we have engine parts spare which may interest someone, a pair of cylinders, crank cases and crankshaft. I am making parts for the engine of the second bike, as i do this I make double the amount so the third engine is becoming more complete, I am working on the gears and valve gear at the moment.
Just finished fabricating the carburettor for the second engine (have made the parts for another one but not silver soldered it up yet) see attached photo, i will have a go at nickle plating the carb, anyone know if they were bright on matt plated.
Lots to do before pioneer run 2014 !!!!
Chris



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[Chris54]

Well I plated it dull to start with but it showed every finger mark,
So I found the metal polish, didn't take much rubbing to bring it up.
I guess the originals would have been bright plated.

[cardan]

I think it looks beautiful Chris, and probably very close to original. The process used back them was Watts nickel, a simple chemical concoction with only 4 or 5 basic chemicals. The brighteners found in a modern plating bath weren't yet discovered. From what I've seen the plating process back then involved metal finishing (polishing the easy to get at bits, leaving the corners, crevasses, undersides etc. as cast or as machined), followed by plating, followed by a quick polish of the plating. The plated item then then takes on any and all imperfections of the underlying metal.

How's the rest of the bike going?

Leon

[Chris54]

Thanks for the comments, Leon. My plating was done with three chemicals to make the electrolyte'
I didn't use any brighteners, just bras so on the parts I could get at.
As for the rest of the bike, got to build the engine' couple of parts to make and then to the tank, going to make this from brass sheet for ease of soldering and keep the corrosion problem away, will post photos as I go. Was wondering if anyone has original drawings for the tank as we have nothing at all, I have measured up another one but have seen them with and without sight glasses for the fuel and oil, anyone know which is correct for 1911
Chris.

[cardan]

Hi Chris,
If you used chemicals to make up your bath (rather than Willy Wonka's Super Shiny Plating Mix), you've gone it much the same as they would have at the factory. Maybe they put copper on first, but that usually involves cyanide!
Re using brass for the tank: I'm told that building brass tanks is tricky, because the brass conducts heat so well it's hard to solder the new bit without unsoldering the old bit. Also the brass tends to ripple where it is soldered. The easiest material to use is said to be "turn plate" (I think), but like many things to do with restoration its hard to source these days. I have a sheet waiting for a tank I have to make.
Leon

[eddie]

The secret to soldering up any tank (irrespective of the parent metal) is to use the largest copper bit (soldering iron) that you can handle - one that makes your arm feel as if it's dropping off after 1/2 an hour is ideal. Something this size stores (and gives off) enough heat to be able to draw the molten solder along the joint without heating the whole tank to the point of collapsing again. Always use tinman's solder - this flows more readily than plumber's solder, which goes through the semi liquid state that is required in order to be able to 'wipe' joints on lead pipework.
   Regards,
                 Eddie.

[Chris]

Hi all
   The correct term for the material to use  for the petrol tank is "Tin Plate". This is a thin sheet of steel tin plated both sides. It is ideal for making tanks as it is already "tinned" so with a minimum of flux the solder flows easily making perfect joints. It used to be available in a large range of gauges and sheet sizes but with the loss of much of the technology and manufacturing base it is now much more difficult to source. It is still available in limited quantities in sheet sizes of about 750mm square, more than enough for a tank and the nearest gauge to that used by Douglas on the flat tank machines is 0.6mm (yes: even that has gone metric) which is about one thou thinner than the original standard wire gauge used. In respect of the tank for the 1911 machine I made one several years ago and wrote it up in the LDMCC Magazine New Conrod . I am not sure whether I subsequently placed it on the Forum. Perhaps someone can find it and if not on the Forum place a copy from the NCR. It does not give dimensions but does show all of the individual parts laid out and describes the construction. It was complete with both the oil and petrol sight glasses. Chris.

[ccew350]

Chris. Don't know if it is of any help, but I found the post re your 1916 tank. This has a picture and some measurements.
It is the only post of yours I could find regarding tanks.
To find it I put 'veteran fuel tank' in the search box. It is number 4 in the list.
Regards, Colin.

[Chris]

Hi Colin
  Thanks for that but that one is another tank that I made. It is the same as the veteran tanks with fillers on the left hand side and used from 1912 to 1919. I will try to look for the original article on the 1911 tank which is even narrower, has a cut out tunnel for the magneto and small diameter fillers on the right hand side and sight gauges for both oil and petrol.  Chris.

[cardan]

Hi Chris,
Yes it is sometimes called "tin plate", but "terne plate" (not "turn" as I guessed; I don't think I've ever seen it written) is I think the correct term - coated with an alloy of lead and tin i.e. solder. Of course we would call it "tinned" if we put it there with our soldering iron! http://www.merriam-webster.com/dictionary/terneplate
Leon

[Dave@NZ]

Hi Chris and welcome,
You have made a fantastic job of making  the new carburetor.
Dave.

[Chris]

Hi
I have found scans of my original article and photos concerning the manufacture of a petrol tank for the 1911 model D Douglas. Pictures to follow. Chris.



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[Dave]

Photos added.

[Chris54]

Hi all
Thanks for all the comments and info, will add comments when I get to my PC.
Chris

[Dave]

I posted two copies of page 2 when adding the photos to Chris' post above. Now corrected to show page 2 and page 3.

Dave

[Chris54]

Thanks Dave, looks very much like we approach the job s similar way, i have a cardboard tank, unfold and it looks like your graph paper, i agree with Eddie, brass does take a lot of heat but i have an electric iron that looks like a small axe, 3/4" Dia copper bit, have soldered 2.5mm brass sheet no problem, the only reason i am going to use brass is to keep the rust moths away, have used tinplate for a water tank in the past and found that when soldering the tin plating is sucked into the solder joint and leaves the plating very thin close to the joint which leads to corrosion setting in very quick.
My mail problem is that i need dimensions of all the tank fittings, these i will have to make, good job the brass swarf is recycleable

Chris

[cardan]

Superb job on the tank, Chris1! As a sucker for early machines, I'm extremely jealous. Are there photos of the complete bike posted somewhere on the site?

Hope your tank turns out as well Chris2.

Leon