Force gauge for DIY bottle jack press

I’m building the bottle jack press this weekend to experiment with overprinting with multiple plates, since quotes I’m getting from pro presses for the job are horrendously expensive and I’m getting conflicting information about feasibility, etc.

I’d like to ensure that I can get more consistent impressions that just guessing that it “feels right” when I crank the jack up.

Is anyone aware of a force gauge I can put between the top of the bottle jack and the top beam to accurately measure vertical force?


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Can’t help with the force gauge. As an alternative, put the correct height metal bars on the sides of the “platen,” so you can just go down as far as the metal bars, and the metal bars will keep you from going down any farther and crushing the plate. They will also make your impression consistent every time. You could probably also use hardwood like oak or maple, which would be easy to rip to the right height with a table saw. You could experiment with different heights, slowly ripping the bars down until you get the impression you want. We call these bearers.

Quality American-made hydraulic jacks have a port for attaching a pressure gauge.

magnetic base dial indicator? they are cheap.

nuttish, wooden spoon or baren and some elbow grease
printing has never needed hydraulics.
best james

Hey Nuttish- It’d also probably be a better design if you could invert the pressure- meaning the jack faced down. Most of the paper presses (which are not that different from what you’re describing) out there that rely on hydraulic pressure have the piston on the top/stationary bed on the bottom. Just a thought.

Examples from Carriage House:

With respect to the above contributors, just additional observation and suggestion, the pressure guage in the adaptor on the bottle jack will only tell you what pressure at P.S.I. the hydraulics produce it wont relate to crushing/impression pressure on your item to be printed, you couldnt co-relate for tiny print area up to capacity, (without some serious calculations) One possible solution, with judicious use of 5 (FIVE) identical height pressure points i.e. one at each corner of your impression area and one in the middle, utilise your bottle jack coupled to a common or garden mechanics torque wrench usually calibrated up to 120/150 foot pounds, and variable up to the limit, operate progressively adjusting upwards against your spacers until you arrive at your desired pressure, most normal torque wrenches “break” or “crack” at the setting you put in. You then can make your own graph as to what pressure you need for what impression area. Obviously a tiny block will need a lot less than a full out forme. On a D.I.Y. basis without massive expense this would be my take on it, with one more proviso as posted by learned friends re another discussion, expecting to get more than 50/60% of overall impression/contact seems to be the advisable limit, one would think that this principle holds good with your press, in view of your anticipated pressure requirements!!!! Should this be treated as a serious possibility it may be necessary to make a small adaptor for the torque wrench onto the bottle jack.>>> (what are you anticipating doing? greenbacks 32 up maybe) >>Seriously Good Luck Mick .>>> Would appreciate any comments/critisism good or bad, and on line results whatever you achieve. A few here in U.K. are interested.

If you can read the pressure in the jack, then you know the force being exerted. Mick is correct in that you need more force for a larger print area. The calculations aren’t that difficult though.

Pressure = Force / Area

So, if you know the pressure in the jack, and the Area of the Jack’s piston, you know the force applied to your plate.

With that, and the area being printed, you know the pressure being applied to the paper. In theory you want that to be roughly the same regardless of print area.

The original question had to do with consistency. The pressure gauge would get that for you if you determined the correct pressure for a given plate. The only trick is you would use a different pressure for a larger or smaller plate.

Luke, Thanks for your back up, your last paragraph said briefly that which I (admittedly) rambled a bit with but keeping the original query in mind (which does seem to get overlooked frequently) my torque wrench principle was an attempt, to provide a yardstick, with graph and calibrations, to accomodate the range of pressures, pro rata for the size of reproduction, exactly as you imply, combined efforts may help the Main Man to NOT blow the top beam of His press, or crush His teeny, water soluble plate!!! Thanks Again. Mick