First step is to cut the brass stock up into the proper lengths. I allow a little extra length when cutting as I will true up the ends and machine to length in the lathe. |
This is a far into the four jaw I could get the 5/8" square bar. The left end hits the taper in the head of my lathe. I am cutting down to the shiny line. |
This is the frame side rail which is 3/8" x 5/8" brass bar. This shape will fit completely through the head without impacting the hole. |
This is the left end of the side frame sticking out through the hole through the lathe head. Doesn't everyone have a hole in their head? |
Kozo calls for the side frame to be 5/8" x 5/16" brass. I couldn't find 5/16" so I purchased 5/8" x 3/8". I decided to mill notches where the bolsters fit into the frame. It looks good but isn't really necessary. It is easier to just shorten the two frame bolsters by 1/8". See next picture for explanation. |
This is the two side frame pieces after I milled the notches (1/16" x 5/8") and I am laying out the bolt holes for the bolsters. Cutting the notches on one side of the bar relieved some stress and caused a slight (about 1/16") warp in the bar. I think I can take the warp out but brass bar is a lot tougher than I imagined. |
This is my patented, "left hand over head" drilling feed position. I am also sitting on a high stool. This frees my right hand for applying drilling fluid, etc. |
This is the outside perimeter frame for the tender. The front and rear sills are fully machined except for some match drilling.
I just ordered another $200 in brass and copper which should get me close to all I need for the major tender parts. That doesn't include some of the detail material and the water pump materials. |
Here is the material order. Copper and Brass. That is the tender frame (before end drilling) in the background. The smaller brass plate wrapped in plastic and just at the top of the copper sheet will be the floor of the tender. |
This is the corner of the large sheet of brass. I was able to flatten most of it out. This is the way shippers handle freight these days. I don't think this corner was critical. We all live with shipping damage. |
My concern was how to align the frame and drill the ends of the brass bars. Here is my method of clamping the corner. I use a polished granite floor tile as my flat plate. Next I spot drill through the existing holes using a bit in a hand drill to mark the centers |
This is the result. Of course I number all the pieces so they all go back together in the correct order. That granite tile is plenty accurate for my kind of measurements. |
Here is my method of drilling the ends of the long pieces. Where there is a will I can find a way! The flat sides on the screw less vice help keep it accurate. |
This is the first full assembly of the tender frame. I am quite sure it will not be the last. It is perfectly flat and no rocking on the plate. The more pieces I assemble the more I realize the size of this project. Impressive. |
The saw is running but the fast digital stopped the action again. I have to be very careful to watch out for interference between all the parts. The extra clamp keeps vibration to a minimum. |
This is all the brass pieces after cutting and notching. All parts started out from flat sheets of brass. Strips must be cut and sized before notching with the rotary saws. |
Here is how I hold the steps in the first solder step. If I didn't clamp in this fashion the assembly would probably be out of alignment. You can see the red glow in the brass which is the proper temperature. This picture was taken just a few seconds after soldering the joints. |
This is the first stage after pickling. The joints are excellent. The long tabs will get cut off in later steps. |
This is the stage two brazing |
Nice start. Now I have to solder on the back plate and start filing to shape. Those joints look great! |
It's now 8/22/10, Really!
The back plate is sanded shiny clean and the back side of the "ladder" has been filed flat which also cleans the brass. |
Flux has been liberally applied and the silver solder "bits" have been dropped into place. |
Here is the assembly a few seconds after the torch was taken away. It is still very hot. The last three pictures the part has been setting on the lightweight firebrick |
These two parts have been fully soldered and are fresh out of the sulfuric acid pickling bath. Note how well the silver solder has flowed. It might be a tad too much but really quite satisfactory. |
This is one of the prime reason I bought the little Proxxon band saw. |
It is perfect for cutting out parts like these brass steps. Here I am removing all the tabs and excess back plate |
Both steps have been trim cut with the band saw. The best blade to use is the bimetal (10 - 14 TPI) blade. Also the most expensive, but it is good! |
I chose hand filing but gave serious thought to using a powered hand burr. The file is the only option for close detail on this thin brass. |
The step on the left is nearly finished with the filing. The one on the right shows how much needs filed away. It hasn't been touched by a file. |
It was 101 degrees in the shop. Filing is not extremely exerting but it does take awhile. The dew rag keeps the sweat from raining on my work. |
The steps look great! Fabricating parts by silver brazing may seem intimidating but is not problem if you know the procedure and keep the parts clean you want to stick together. |
I stacked up some high speed steel scale ties to show where the steps mount. It feels great to be back to work on the A3 again after a three year hiatus. |
