Today I decided to make a polissoir to see what it was about. I didn't follow any exact measurements but used the broomcorn I had in one broom head as my limiting factor. It was quite easy and works very well.
I picked up a hand broom at the box store. I looked around and found one at Home Depot that was made with broomcorn for about $5. It is important to note that they are changing out this broom for one that is made with straw. This one is tan and the straw one was a sage green color. I wanted a wrap that was presentable, so I picked up whipping twine from the marine (boat/sailing) store. The lashing is way more that I need and was $9. I used maybe $0.75 of twine.
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The end of the hand broom looked like this. The broom is 100% broomcorn.
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I didn't take pictures of the entire process but this is what I ended up with.
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This is a No 3 for size comparison. The polissoir is 1 1/4" in diameter and 5 1/4" long.
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After use on about 1/2 of a square foot and no wax.
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This was a few strokes with moderate pressure on walnut. This board was planed smooth with the No 3 prior to burnishing.
Overall there are a couple of things I would change. I would use 1 1/2 to 2 hand brooms of material in the next one, maybe 2" in diameter. I would use the middle area of the broomcorn for the end. The middle area is the thickest solid core area in the plant. The fine ends and open core bottom seem to be a little less desirable and not as solid. The whipping twine is waxed and works quite well. It has a little stretch that helps keep things under tension when making. I used 2 hose clamps to keep the broomcorn compressed as I wound the twine.
I can do a more in depth DIY if people are interested. It wasn't too bad to do myself and would recommend it for those who enjoy making their own tools.