This little steam loco project is a single cylinder oscillator, gear and chain driven, 0-4-0 in 7/8 = 1 foot scale. The engine is single acting with a 1/2" bore and 11/16 stroke. The transmission is by gear to an intermediate shaft and then ladder chain to the lead axle. Total gear reduction is 4.8 to 1. That should provide some power as well as speed. The boiler is a single flue, gas fired T boiler. The vertical leg of the boiler should provide a lot of water and steam space while the horizontal leg provides room for a larger than normal flue.
This one is called Nina.
The primary inspiration for the Nina project is Mr Earnest Glasers Cracker. This is Mr Glasers original Cracker.
Here is a link to Mr Glasers plan set for Cracker.
http://home.iae.nl/users/summer/16mmngm/Articles_htms/Cracker.htm
Cracker is a Gauge 0 engine in metric dimension. For this project I plan to use the motor unit with a scale of 1mm = 1/16 to make it larger.
The chassis comes from Idris, designed and built by Mr Dave Watkins.
Mr Watkins original Idris is in 16mm = 1 foot scale. I scaled up the chassis by a factor of 1.4 to get it to 7/8 scale. The Idris chassis will give Nina a longer wheel-base then Cracker and more room for the boiler. Dave has a plan set for Idris and his other engine at his website
http://www.davewatkins.pwp.blueyonder.co.uk/steam.htm
The rest of it will get made-up as we go along.
First parts to make are the main frames. They are from 16 gauge (.0598) cold roll, bright finished, steel plate. Here is the frame drawing:
http://1stclass.mylargescale.com/xo18thfa/Nina%2001/frame%20drawing.jpg
To start, saw out two rectangles, slightly over sized. 16-gauge plate is easy to cut. Clamp the sheet over the edge of the workbench with a piece of wood strip on top to keep it from chattering. Use a new blade in the hacksaw with a good shot of oil. Dont push down too hard, let the blade do the cutting.
Finish the frame blanks so the edges are flat, sharp and square all around. First, paint a line of blue Dykem layout fluid on one long edge. With a straight edge, scribe a line close to the rough-cut edge:
Use a bench grinder to off-hand grind the sawed edge, close to the line.
Your eye is very precise for this kind of work. You will get within .002 to .003 of the line with the grinder. If the grinder starts to chatter, its because the wheel is getting clogged with steel bits. Use a dresser to clean the edge of the wheel. Dont let the steel get hot. If the Dykem blue gets hot, the line goes away.
After grinding, polish the frame edge with a technique called draw filing. Clamp the frame between slabs of wood in the vise. Squirt oil on a clean sharp file and hold it by both ends. Gently rub the file forward and back. Heres my son Andy doing the draw filing. Hes standing to the left, just out of the picture.
Work the entire length of the edge to remove the grinder marks. Draw filing removes metal fast, so dont push too hard. Little curly hairs of metal come off the edge like butter. The file teeth will clog up, so clean the file frequently.
Check your progress with a straight edge, holding it to the light. When you see a thin even line of light, the frame edge is flat.
After draw filing, the frame edge is polished bright and razor sharp. Use a fine file to take the sharp edges off.
Use a square mark off one end. Just as before, grind and draw file the end. Use the square to check progress.
Grind and draw file the remaining edges. This takes a little more time because you have cut the frames to final length and width as you make sure the edges are flat and square.
Clean up the frame blanks. Paint one side of one frame blank with Dykem blue. Measure and layout all hole centers and the curved out areas on the bottom edge.
From this point one we will work on both frames simultaneously. In the area the eventually gets wasted out on the bottom edge, drill holes for some #4 x 40 machine screws. Bolt the two frame blanks together.
The photo above does not show all the scribed lines in the Dykem blue showing all the hole centers. They are all in there, however. Lightly center pop all the hole centers.
Admittedly, four-squaring stock is not much fun, but its essential. Next time we will drill and shape the frames in prep for assembly.
This one is called Nina.
The primary inspiration for the Nina project is Mr Earnest Glasers Cracker. This is Mr Glasers original Cracker.
Here is a link to Mr Glasers plan set for Cracker.
http://home.iae.nl/users/summer/16mmngm/Articles_htms/Cracker.htm
Cracker is a Gauge 0 engine in metric dimension. For this project I plan to use the motor unit with a scale of 1mm = 1/16 to make it larger.
The chassis comes from Idris, designed and built by Mr Dave Watkins.
Mr Watkins original Idris is in 16mm = 1 foot scale. I scaled up the chassis by a factor of 1.4 to get it to 7/8 scale. The Idris chassis will give Nina a longer wheel-base then Cracker and more room for the boiler. Dave has a plan set for Idris and his other engine at his website
http://www.davewatkins.pwp.blueyonder.co.uk/steam.htm
The rest of it will get made-up as we go along.
First parts to make are the main frames. They are from 16 gauge (.0598) cold roll, bright finished, steel plate. Here is the frame drawing:
http://1stclass.mylargescale.com/xo18thfa/Nina%2001/frame%20drawing.jpg
To start, saw out two rectangles, slightly over sized. 16-gauge plate is easy to cut. Clamp the sheet over the edge of the workbench with a piece of wood strip on top to keep it from chattering. Use a new blade in the hacksaw with a good shot of oil. Dont push down too hard, let the blade do the cutting.
Finish the frame blanks so the edges are flat, sharp and square all around. First, paint a line of blue Dykem layout fluid on one long edge. With a straight edge, scribe a line close to the rough-cut edge:
Use a bench grinder to off-hand grind the sawed edge, close to the line.
Your eye is very precise for this kind of work. You will get within .002 to .003 of the line with the grinder. If the grinder starts to chatter, its because the wheel is getting clogged with steel bits. Use a dresser to clean the edge of the wheel. Dont let the steel get hot. If the Dykem blue gets hot, the line goes away.
After grinding, polish the frame edge with a technique called draw filing. Clamp the frame between slabs of wood in the vise. Squirt oil on a clean sharp file and hold it by both ends. Gently rub the file forward and back. Heres my son Andy doing the draw filing. Hes standing to the left, just out of the picture.
Work the entire length of the edge to remove the grinder marks. Draw filing removes metal fast, so dont push too hard. Little curly hairs of metal come off the edge like butter. The file teeth will clog up, so clean the file frequently.
Check your progress with a straight edge, holding it to the light. When you see a thin even line of light, the frame edge is flat.
After draw filing, the frame edge is polished bright and razor sharp. Use a fine file to take the sharp edges off.
Use a square mark off one end. Just as before, grind and draw file the end. Use the square to check progress.
Grind and draw file the remaining edges. This takes a little more time because you have cut the frames to final length and width as you make sure the edges are flat and square.
Clean up the frame blanks. Paint one side of one frame blank with Dykem blue. Measure and layout all hole centers and the curved out areas on the bottom edge.
From this point one we will work on both frames simultaneously. In the area the eventually gets wasted out on the bottom edge, drill holes for some #4 x 40 machine screws. Bolt the two frame blanks together.
The photo above does not show all the scribed lines in the Dykem blue showing all the hole centers. They are all in there, however. Lightly center pop all the hole centers.
Admittedly, four-squaring stock is not much fun, but its essential. Next time we will drill and shape the frames in prep for assembly.
) 40 mm from back to back of wheels would be 1.5748 in. Right?
