Thanks to Hannah McAndrew for introducing me to this type of slip trailer. This is the type that Hannah uses in her work. This trailer was thought up by Mary Wondrausch, a very famous slipware potter from England. You can learn more about her in her book, On Slipware.
These are all the parts needed to make a trailer. A length of bicycle innertube, a mechanical pencil (I used .7mm), a binder clip, some wire, glue, and a cork that will fit snugly into your innertube. (with a hole in it big enough to accommodate the pencil diameter)
I used the Dremel tool to dissect my pencils. Cutting them off and then removing any unnecessary inner parts.
I drilled the cork on the drill press (easier than trying to hold it with a handheld drill) and then glued the tip in place. (The Gorilla Glue is a bit of over kill for this job but it's what I had on hand)
Next, the cork is inserted into the tube and secured with wire. I twist the wire with pliers to really get a good grip. (This is an upgrade from Hannah's model, which used smaller gauge wire. I used 12 or 14 gauge electrical wire)
Here are two finished trailers. The top one that I made and the bottom one is the one Hannah sent me.
These trailers extrude a very nice line of slip. The slip must be sieved well through a 100 Mesh screen. They are filled through the back end all the way to the top. The innertube is folded over allowing any excess to spill out into a bucket. Secure with the clip and wash the mess off the outside, then you're ready to go.
The slip need not be too mixed to thinly as it will only drip through the tip. I am learning what works and what doesn't through trial and error. You could certainly move up to bigger diameter tips.
I don't do much trailing in my work but I do love the technique and have enjoyed playing with this tool. My class at clayworks made several of these last night and we are all going to be learning to use them together.