12-20-2016, 01:34 AM
To make reproduction dogbone resistors I start with polystyrene tubing made for model railroads:
http://www.evergreenscalemodels.com/Shap...d%20Tubing
The best thing about it is that it comes in a number of different diameters - for whatever wattage resistor you need to reproduce. It's readily available on eBay and Amazon.
I use a hobby mitre saw to cut it to length. All of the out-of-tolerance resistors on this Philco 50 are 1/2W and 1" long.
[Image: http://i1072.photobucket.com/albums/w374...mnwdux.jpg]
I use wire snips to make a small notch for a length of bus wire on each end. I used 5.5" lengths of 18ga bus wire for these.
I use a wire wrap tool to roll up the original resistor leads and solder the bus wire to each end:
[Image: http://i1072.photobucket.com/albums/w374...eiiykw.jpg]
Then I insert the resistor plus bus wire leads into the tube and wrap the leads around the outside:
[Image: http://i1072.photobucket.com/albums/w374...brytpa.jpg]
And finally solder the wrapped leads so that they'll stay together. Finally, I use hot glue to fill / seal up the ends.
[Image: http://i1072.photobucket.com/albums/w374...xpshbm.jpg]
I know I've seen others use JB-Weld to hold things together and to fill the ends - which works great, but is a bit messy and of course takes time to cure. The above method lets me build the resistors in one pass, which is helpful since painting takes a day or so.
http://www.evergreenscalemodels.com/Shap...d%20Tubing
The best thing about it is that it comes in a number of different diameters - for whatever wattage resistor you need to reproduce. It's readily available on eBay and Amazon.
I use a hobby mitre saw to cut it to length. All of the out-of-tolerance resistors on this Philco 50 are 1/2W and 1" long.
[Image: http://i1072.photobucket.com/albums/w374...mnwdux.jpg]
I use wire snips to make a small notch for a length of bus wire on each end. I used 5.5" lengths of 18ga bus wire for these.
I use a wire wrap tool to roll up the original resistor leads and solder the bus wire to each end:
[Image: http://i1072.photobucket.com/albums/w374...eiiykw.jpg]
Then I insert the resistor plus bus wire leads into the tube and wrap the leads around the outside:
[Image: http://i1072.photobucket.com/albums/w374...brytpa.jpg]
And finally solder the wrapped leads so that they'll stay together. Finally, I use hot glue to fill / seal up the ends.
[Image: http://i1072.photobucket.com/albums/w374...xpshbm.jpg]
I know I've seen others use JB-Weld to hold things together and to fill the ends - which works great, but is a bit messy and of course takes time to cure. The above method lets me build the resistors in one pass, which is helpful since painting takes a day or so.