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Stock Size

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There was some discussion  about what size stock to use for forms.  Here are the responses:

Were I to make new forms I would use the 1" x 1". The extra width of the forms will give you more support for the plane, though it is not needed, but the extra depth will allow you to make some rods with really large diameter butts, if you so choose. Because of the shoulder bolts I used in my ¾" x ¾"  forms, I could only get butt diameters of .368. across the flats.  (Martin-Darrell)

I see no reason to make the forms any wider than 3/4"x3/4" bar stock. The one I made years ago I made from Brass bars. In my opinion it's much easier to machine (as I did with hand tools) and no bother with rust. Also it seems more flexible for a greater ability to make larger station to station dimension changes (ie. Swelled butts). (Marty DeSapio)

People like the larger forms because they have less tendency to shift on the bench, and they are probably less sensitive to temperature changes. I think that the slimmer bars are often used because they are easier to drill and tap, especially if one is using a hand held drill and not a press. Less expensive as well.  (Jeff Schaeffer)

I'm currently making my forms from 1" square bar.  The bolts and dowels that I purchased cost me 37 dollars with our company "discount".  I am making 6 foot long forms, so not only are there longer bolts to consider, but two extra stations.

There are several downers to the bars that I started with, and could hit you as well.

1. As you are filing your bars flat, you have 2" worth of metal to even up, 33% more than if you used the 3/4" keystock.
2. The bars are 1026, harder than necessary.  I should have purchased mild steel which would have been easier to hand work.
3. The bars lived on a rack outdoors for several years, and the pitting present has required a WHOLE LOT of hours with file in hand.  This squaring/flattening phase is not all that fun.  The first 20 hours were, but not any more.
4. These buggers are HEAVY in a serious sense.  The extra rigidity is probably not necessary, as your plane is going to follow the top of the forms even if they are slightly bowed.  Your strips should stay on dimension unless you have some serious doglegs or other obvious geometrical flaws.  (Troy Miller)