It's hit or miss.
I have made over a hundred from any where between a slim line to a cigar.
The key is to use a kit that is about the same size tube as the size of the waxy pith you are going to drill out.
I rough turn the cobs prior to drilling to get the "fuzz" off.
At some point you are going to cut the cob.
(There are other ways but if it's your first I don't recomend it)
Once you cut the cob for a rough length of the tubes you'll know what size kit will work best with that kit.Leave a little extra and stabilize the ends before you mill it.
The fattest cobs don't always work nor do the skinniest.
Some cobs just won't make a pen.
I don't mean to make this sound discouraging.It isn't really that tough.
If you are not stabilizing the cobs prior to turning make sure you have some thin CA.
As you turn off the CA'd portion stabilize with CA again.
Keep your tools sharp.
Here's the first one I made.(first attempt)
It took five tries before I got the second one and I had already sent this one to the guy who supplied me with 3 year old dried corn cobs.
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