Canadian 10cwt Trailer rebuild

[Jordan Baker]

Hi all.

I just picked up this nice Canadian 10cwt trailer on the weekend. No data tags were on it. However this thread http://www.mapleleafup.net/forums/showthread.php?t=892, is also about this same trailer. So at least I have one number.

Yesterday I started in on the restoration of it by pulling it all apart. Other then needing two GPW/MB rims, it is a very complete trailer. Most of the rust is limited to surface rust. I may have to replace the sheet metal for the floor and the hat channels as they appear to be rather thin. I am not too sure how they will look once sandblasted.

One interesting point that I can't quite figure out. The front mounting brackets for the tow ring are back to front. The mount with the 4 springs should be located at the front end of the trailer. However it isn't a simple swap the parts around as the hole spacing is different and the frame is welded to the trailer. I wonder if this was a production error that slipped by the inspector.

[Jordan Baker]

Tear down begins. They sure didn't skimp on the bolts. By the time I was done I had two rather full bags of them.

[Jordan Baker]

Lastly the back to front tow ring setup.

[Grant Bowker]

Looking at the pintle setup, it looks as if all of the parts are fitting well with respect to each other. You would think they would have wanted the two solid supports as far apart as possible for strength (with the friction block between), that doesn't seem to fit with your parts or the manuals. If the drawbar is different diameters in the solid mounts and friction areas, that would be just too much to be a production error (manual seems to show only one diameter). I agree the photos in the AEDB Design Record and the Maintenance manual both show the friction block at the tip of the drawbar. One theory might be that the manuals used photos taken early in production and that a change was made part way through for an unknown reason. Another theory would be Brantford Coach & Body making the assembly one way and Frost & Wood doing it differently for their production. It will be interesting to see what others have on their trailers.

Is that a grease fitting on the top of the spring loaded part of the drawbar assembly? On the 15 and 20 cwt trailers, the spring loaded part contains friction blocks to reduce fore and aft surging against the brakes and there are specific cautions not to lubricate this area. I'm curious what you find when you open this area - steel, bronze bush, brake lining material?

[Jordan Baker]

I found another trailer that is in Italy with the same setup. However it is missing the two frame rail risers. It still has its data tags on it and I have emailed the owner for more info.

[Grant Bowker]

I am not a vehicle design engineer but I think I prefer the way your trailer is built over the design shown in the manuals. The way it is shown in the manuals, the springs are under constant load to support the tongue rather than just providing a friction load.