Building Screws from Scratch

Created by James Tuxbury

Click on the highlighted words for a picture.

The first thing I do when I am making a screw is to buy some brass stock from Small Parts inc. usually I get a 12 inch rod.
I make two cuts halfway through the rod for the thickness of the hub with my hack saw, then make a through cut about an inch
farther up the rod. this leaves me with a rod about 2 inches long. Then I find the center of the rod as shown in the same picture
and drill through the center of the rod. That is what I use as the hub .


I also purchase some flat stock usually 3 inch X 12 inch X .65 this is what I cut the blades out of after
drawing on brass the shape of the blades . Diagonial lines are then marked on the side of the hub where I cut a groove to
insert the Blade into the hub. As shown two blades in cutout in the hub. The next photo four blades and hub show the shape
of the blades and the hub with lines drawn to show where the hub should be cut.

I then clamp the hub into a vice and use two nuts to hold it in place.I then try fitting the blade prior to welding blade in place.
Here comes the fun part. I break out my acyetalene torch and braze the blades in place. It isn't much harder than
sweating a pipe joint, you just need an acetylene torch and it is something you just have to learn on your own,
there are numerous sites on the web to guide you.


Next photo shows blades being curved in a form it is nothing more than a block of wood cut in a curve and placed in a vice.
The blades bend to the curve very easily. This photo shows the blades welded on before cleanup and finally the polished blades.

The following links are a
synopsys of the above photos.

Building a stuffing box

The pictures below show how I build a stuffing box, it is nothing more than three brass rods the outer one is the largest diameter
then two small end pieces inserted one within the other and soldered in place. When I have completed the model I stuff the box
with automobile wheel bearing grease using a syringe. Then I run the shaft through and put a collar on the end to hold it in place.

Speed Control Subsystem

LXKAL6 from Tower Hobbies is the speed control I use its mechanical and really can take a beating. It is a Tamaya device
and the part number is Model SP1198 part#51198 for those who would rather not use Tower. I build it as a subsystem then
I install the whole thing at once.