Drive Wheel

This is a quick tutorial on how I converted a caster into a drive wheel for my feet kits.

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Here is a caster that I purchased at a surplus store. A blue rubber wheel for R2. Perfect. Later on you will see what is needed to convert this into a drive wheel

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You will need a tap. In this case I am using 1/4-20 set screws so I need a tap this size.

 

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Here is the weapon of choice for an R2 Builder. The Dremel tool. On the end I have a sanding drum

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You will also need a drill with a 7/32 drill bit. This is the recommended size for the 1/4-20 tap.

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Not necessary but helpful is a measuring tool. Here is a dial caliper.

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Here is the caster with the bolt taken off.

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A super close up of the hub area. I chose this caster because there is material in the hub area where I can drill, tap and put in a set screw.

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The bearing inside just pops out.

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The area inside the hub measures over 0.750 inches which is what my drive shaft is. No worries as I will use a thin brass sheet to build it up to the 0.750 in dia I need

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Now I measure the inside of the wheel bracket. The wheel will have to fit in here.

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Doh! The width of the wheel at the hub area is larger than inside the wheel bracket.

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The R2 Builders tool to the rescue. I grind down one side until it fits the wheel bracket.

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I check every so often until the wheel fits in.

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Next I notch the wheel 90 degrees to each other. I have made 2 notches for 2 set screws. You can do as many as you want but I suggest the minimum be 2.

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If I didn't notch the wheel sides the closest I can get with the drill bit does not leave much material above the drill bit and this can be a weak point that may break.

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Compared to the picture before there is more material above the drill bit.

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Next we tap the hole to the desired thread.

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Here is the Allen key and the set screws

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The set screws are carefully inserted. Do not force the set screws as the hub is a soft material and you do not want to damage the material

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Here is the shaft installed through the wheel. I have used sheet brass to give the shaft and wheel a tight fit. If it was loose the wheel may not rotate properly.

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When tightening the set screws do not use excessive force or you may damage the wheel hub.