When you want to make something that will take a lot abuse, like the axle guides on a giant scale airplane’s landing gear, there’s nothing tougher than steel. For my current 27.5% scale Nieuport 24 WW I biplane project, I decided to use 0.032 (1/32 inch) mild steel sheet to form the bottom guide plates. Very similar to working with sheet brass, steel requires the same techniques, but it takes a little more effort. Also, rule no. 1 while working with sheet metal and steel, always wear eye protection!
Here’s how I did it.
First find a scale drawing of the part you want to make and then add to your scale drawings.
Now draw the part full-size for your model (I used CAD), and then print it out to use as a template. To attach the paper template to the sheet metal, I use spray adhesive. Also needed are a Dremel rotary tool with heavy duty reinforced cut off discs, drill bits the sizes needed to drill the holes, and a pair of vice grips to hold the parts while it is being drilled.
I prefer to use the newer Dremel EZ Lock cutting discs as they are quick to replace as they wear out and are very durable and do not break easily with a side load.
To cut the pieces roughly to shape, clamp the sheet metal to a scrap piece of wood so the part doesn’t move. Then slowly and carefully make multiple straight line passes with the cutoff disc being careful to stay outside of the part’s outlines. Be careful as the parts will get very hot while cutting them out. (Below). Here you see the two pieces cut from the parent sheet of steel. The one on the left has been cut to the rough shape while the one on the right has been dressed down to its final shape with a bench grinder. Also note the the ends of the guide slot have been drilled out with a 3/16 inch drill bit. The material between will be removed with the cutoff disc and then files smooth with a file. All the guide holes have also been drill out including the two lower 3/16 inch spreader rod holes. Note that the holes are center punched before drilling so the bits won’t walk out of position.
Here the piece on the right has been cut, ground and drilled to its final shape. Once this is done, the part can be sanded with 80 and then 100 grit sand paper for a smooth finish.
Here one of the guide plates is being dressed with the grinding wheel. Use the face of the wheel for grinding flat edges and the corners of the wheel for curved edges.
When it comes to drilling the holes in the steel parts, clamp them to a scrape board and start with small plot drills and slowly work your way up to the final size you require. I have had good results using stepped tip drills that have a small pilot drill at the tip. This way you can save time by eliminating drill bit changes.
Here the two axle guide plates are finished and ready to be silver soldered to the landing gear strut wires.
But that’s another How To article! With some practice, making brackets and other heavy duty fittings from mild steel is fairly easy. Don’t force anything and while drilling, let the bid do all the work. Forcing things will dull your tools and produce an inferior part.
