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mark61
08-13-2010, 09:44 AM
I scored a new rack 1" thick by 1 1/2" wide and a gear that matches it to buld a hand arbor press (some day). The gear is a Martin S636 14 1/2* 36 tooth 6.333" OD. Can someone estimate the "tonage" I will get with this combonation? I plan to double the rack thickness to 2" by welding some 1" x 1 1/2" to it. The gear seems way big for a hand press. What size do you think a bought press would have?

TIA!
mark61

J Tiers
08-13-2010, 10:03 AM
Your force will be multiplied by the lever arm.....

Radius from pinion shaft center to pitch line vs length of lever, basically, multiplied by the force you can apply to the lever.

if you weigh 200 lb, and basically hang on a lever that is 10X the pitch radius of the gear, you would have about a ton. Less friction, of course.

Gear seems over-large.

You can probably buy a serviceable press for a lot less than you can build it for, unless you have access to lots of suitable scrap metal and a welder.

I saw a fabricated press a few weeks ago when I bought another mill. It was a beast. I wanted the table the mill was on as well, but the press was on it and we couldn't move that press. 3 feet tall, 2+ feet deep, over 15" wide and made of 20 lb (0.5") plate..... I did manage to lift an end, but no way were we wanting to lift it by hand and lower it to the floor.