A couple of 122-key IBM Model F's

[jacobolus]

Oh darn. I offered $80 for the $189 one, he countered with $130, and then a couple days later messaged me saying to offer $100 and he’d accept it. I missed the email until now, and looks like it sold at $130. Oh well.

[pr0ximity]

All this talk of the challenge makes me want to give this a go in the future when I have some additional workshop space and time. What's a fair price for these? Seems to be pretty varied, based on condition and the seller's knowledge of what s/he has.

[berserkfan]

my leather punch (which was old and I spent some time with a file sharpening) over wood did a great job at cutting a hole in just about anything. I got a new one with the express purpose of using it to punch holes in material for model Fs.

I don't get it; a leather punch is for belts and the holes are perpetually way too small. How do you guys chance on precisely the correct diameter for Model F barrels?

[E TwentyNine]

Something like this:

http://www.harborfreight.com/hand-tools/punches/9-piece-hollow-punch-set-3838.html

[1391406]

What's a fair price for these? Seems to be pretty varied, based on condition and the seller's knowledge of what s/he has.

Pretty much. Prices range from approx. $100 to $200.

[berserkfan]

Something like this:

http://www.harborfreight.com/hand-tools/punches/9-piece-hollow-punch-set-3838.html

Aha..

rather than buy all that stuff just to create my own membrane I think I'll just get someone to make it for me...

[fohat.digs]

a leather punch is for belts and the holes are perpetually way too small.
How do you guys chance on precisely the correct diameter for Model F barrels?

The barrels are 1/2" diameter (13mm) but the "buttresses" on the AT & 122 make the 5/8" (16mm) a better choice.

Alternatively, you could just snip a little bite out where the buttress comes through.

For the XT style barrels, the stand-off is a little post.

With the art foam like I use, you could probably just push the barrels in and the foam would deform itself around the alignment tabs. With harder or tougher materials, it might not work as well.

[dorkvader]

my leather punch (which was old and I spent some time with a file sharpening) over wood did a great job at cutting a hole in just about anything. I got a new one with the express purpose of using it to punch holes in material for model Fs.

I don't get it; a leather punch is for belts and the holes are perpetually way too small. How do you guys chance on precisely the correct diameter for Model F barrels?

1/2" leather punch

rather than buy all that stuff just to create my own membrane I think I'll just get someone to make it for me...

Does not fix the problem of the first guy trying to make them.

Alternatively, you could just snip a little bite out where the buttress comes through.

1/2" punch and snip the corner for the buttress was the plan. Would have worked too if I could get it back together with the foam being too thick.