Author Topic: My 4-pulley dutch press  (Read 2158 times)

Offline Tom Turophile / CheeseStud

  • Mature Cheese
  • ****
  • Location: Atlanta
  • Posts: 171
  • Cheeses: 3
  • Default personal text
My 4-pulley dutch press
« on: January 22, 2013, 11:02:10 AM »
And now, the last obstacle to making some real cheeses is complete -- my 4 pulley dutch press, with the small hard cheese mold (diameter 4.5 in.) next to it.



I used some scrap wood leftover from building built-in cabinets; if you exclude the wood, biggest costs was probably the $14 for the hole-cutter to craft the bottom of the plunger.

Now, for the numbers:
Arm length: 35.5 in -- 27.5 from the last anchor to the fulcrum, and 8 in. from the fulcrum to the end.
MA = 4.2; MA total = 21

Therefore 1 lb of pressure proves 21 pounds; divided by the area is 1.32 PSI (per lb).
I just had a tomme mold delivered, but if I were using the mold above...
4.5 diameter
2.25 radius
15.9 area
So 15 lbs for 20 PSI...
CheeseStud(.com coming soon)
4 store-bought cow's milk mozzarellas, 1 rather rubbery raw cow milk mozz, cow's feta that melted, 0 ricotta


Guests, join the CheeseForum.org community to remove this ad.


Offline Al Lewis

  • Old Cheese
  • *****
  • Location: Port Orchard Washington
  • Posts: 1,128
  • Cheeses: 38
Re: My 4-pulley dutch press
« Reply #1 on: January 22, 2013, 11:18:50 AM »
Very nice and now you won't have to lift heavy weights to press the weights you'll need.  I really like the pulley system idea for presses.

Offline smolt1

  • Mature Cheese
  • ****
  • Location: oregon
  • Posts: 154
  • Cheeses: 13
  • Default personal text
    • SturdyPress.com
Re: My 4-pulley dutch press
« Reply #2 on: January 22, 2013, 12:20:31 PM »
What are the 4 square posts in the base used for?

Offline Tom Turophile / CheeseStud

  • Mature Cheese
  • ****
  • Location: Atlanta
  • Posts: 171
  • Cheeses: 3
  • Default personal text
Re: My 4-pulley dutch press
« Reply #3 on: January 22, 2013, 01:20:53 PM »
What are the 4 square posts in the base used for?

Nothing.  I just put that bench together, and that was part of it.  I may be able to use them for stability, later, if I have bigger or multiple cheeses.
CheeseStud(.com coming soon)
4 store-bought cow's milk mozzarellas, 1 rather rubbery raw cow milk mozz, cow's feta that melted, 0 ricotta

Offline Tom Turophile / CheeseStud

  • Mature Cheese
  • ****
  • Location: Atlanta
  • Posts: 171
  • Cheeses: 3
  • Default personal text
Re: My 4-pulley dutch press
« Reply #4 on: January 22, 2013, 01:21:51 PM »
Very nice and now you won't have to lift heavy weights to press the weights you'll need.  I really like the pulley system idea for presses.

I took a while to figure out how I wanted to do this, and once I saw a post about MA here, I knew a few bucks on pulleys would make life much easier.
CheeseStud(.com coming soon)
4 store-bought cow's milk mozzarellas, 1 rather rubbery raw cow milk mozz, cow's feta that melted, 0 ricotta


Guests, join the CheeseForum.org community to remove this ad.


Offline NimbinValley

  • Mature Cheese
  • ****
  • Location: Australia
  • Posts: 288
  • Cheeses: 7
  • Default personal text
Re: My 4-pulley dutch press
« Reply #5 on: January 23, 2013, 11:04:59 PM »
I wish I had your grasp of engineering/weights etc Tom!  NV.

Offline Tom Turophile / CheeseStud

  • Mature Cheese
  • ****
  • Location: Atlanta
  • Posts: 171
  • Cheeses: 3
  • Default personal text
Re: My 4-pulley dutch press
« Reply #6 on: January 24, 2013, 09:00:51 AM »
All information absorbed from posts here -- and physics in 8th grade!  I learned two things as I tried to build my press:

1) The longer the arm (and the distance from the weight to the plunger), the better -- it provides more mechanical advantage (MA)
2) The more pulleys, the better -- it multiplies that MA (by 4, in this case)
CheeseStud(.com coming soon)
4 store-bought cow's milk mozzarellas, 1 rather rubbery raw cow milk mozz, cow's feta that melted, 0 ricotta

Offline Boofer

  • Old Cheese
  • *****
  • Location: Parkland, Washington
  • Posts: 4,226
  • Cheeses: 204
  • Contemplating cheese
Re: My 4-pulley dutch press
« Reply #7 on: January 24, 2013, 09:47:03 AM »
physics in 8th grade!
Really? Amazing. :)

Several questions occur to me from checking out your press:
  • What is the weight of your lever arm and plunger/piston/ramrod? And do you include that in your calcs?
  • It seems like the lever arm would slip out of the guide at the left end if you had to press a tall cheese. There seems to be no provision for stepping the plunger/piston/ramrod up to accommodate a taller cheese. Right?
  • What's the maximum pressure you have tested with your press? That digital scale doesn't look like it would max higher than maybe 11 pounds.
-Boofer-
Let's ferment something!
Bread, beer, wine, cheese...it's all good.

Offline Tom Turophile / CheeseStud

  • Mature Cheese
  • ****
  • Location: Atlanta
  • Posts: 171
  • Cheeses: 3
  • Default personal text
Re: My 4-pulley dutch press
« Reply #8 on: January 24, 2013, 12:54:56 PM »
physics in 8th grade!
Really? Amazing. :)

Several questions occur to me from checking out your press:
  • What is the weight of your lever arm and plunger/piston/ramrod? And do you include that in your calcs?
  • It seems like the lever arm would slip out of the guide at the left end if you had to press a tall cheese. There seems to be no provision for stepping the plunger/piston/ramrod up to accommodate a taller cheese. Right?
  • What's the maximum pressure you have tested with your press? That digital scale doesn't look like it would max higher than maybe 11 pounds.
-Boofer-

1) I haven't weighed them yet, because I found out 1) that the kitchen scale only goes to 11 (cue Spinal Tap) and 2) my bathroom scale is inaccurate due to its non-flat surface
2) At this time, I've got no plans to make taller cheeses, but if I did, I would drill new holes in the plunger and adjust it.  One reason that I kept the arm's height much more than it needed to be was to strengthen it.  One advantage is that if the arm can stand on its own, it won't have friction to contend with, and the calculations will be more accurate.

 I didn't want the left guides to go any higher, but one consideration I have is to bring them in -- that easy enough by unscrewing them, and I think the look would be better (right now, it looks huge compared to others').

3) To be seen...using that bathroom scale, an 19 oz empty paint can provided 32-43 lbs of pressure.  By my calculations -- without the wood's weight -- I should expect 25 lbs.

I'll probably use those calculations this weekend instead of buying a scale (and be sure to include the weight of the wood).
CheeseStud(.com coming soon)
4 store-bought cow's milk mozzarellas, 1 rather rubbery raw cow milk mozz, cow's feta that melted, 0 ricotta

Offline Tom Turophile / CheeseStud

  • Mature Cheese
  • ****
  • Location: Atlanta
  • Posts: 171
  • Cheeses: 3
  • Default personal text
Re: My 4-pulley dutch press
« Reply #9 on: January 28, 2013, 10:18:23 AM »
You see the cross-piece on the bottom right?  Apparently it needs to be a LOT stronger -- after all, it is the opposite side of the weights.  I've broken it TWICE -- just with 20 lbs weighing it down.  I have to buy a 2x4 today and use something that won't snap.  Lesson learned.

Also, I was trying to tie up paint cans to use for the weights -- dumb.  I finally figured out that it is much easier to attach large buckets or bags, and then add the weight as needed. 



The loose pulleys are also not a good idea -- they create slack when trying to put everything together.  I am going to attach them directly later, so that they don't move around and drop their lines.
« Last Edit: January 28, 2013, 10:30:56 AM by Tom Turophile / CheeseStud »
CheeseStud(.com coming soon)
4 store-bought cow's milk mozzarellas, 1 rather rubbery raw cow milk mozz, cow's feta that melted, 0 ricotta


Guests, join the CheeseForum.org community to remove this ad.


Offline H-K-J

  • Old Cheese
  • *****
  • Location: South-east ID
  • Posts: 1,308
  • Cheeses: 85
  • Act as if it were impossible to fail.
    • Cookin with uh dash dogs hair
Re: My 4-pulley dutch press
« Reply #10 on: January 28, 2013, 10:34:00 AM »
Check these out, might help with the pulley problem.  ;)
"Happiness is not the absence of conflict,
But the ability to cope with it."

Offline Boofer

  • Old Cheese
  • *****
  • Location: Parkland, Washington
  • Posts: 4,226
  • Cheeses: 204
  • Contemplating cheese
Re: My 4-pulley dutch press
« Reply #11 on: January 28, 2013, 06:50:04 PM »
Check these out, might help with the pulley problem.  ;)
Yeah, similar to what I used.

-Boofer-
Let's ferment something!
Bread, beer, wine, cheese...it's all good.

Offline Mike Richards

  • Mature Cheese
  • ****
  • Location: colorado springs, co
  • Posts: 446
  • Cheeses: 19
Re: My 4-pulley dutch press
« Reply #12 on: January 28, 2013, 09:13:08 PM »
... the kitchen scale only goes to 11 (cue Spinal Tap)


lol!  I tried to relate that story to someone recently.  They didn't find it as amusing as I did.



Discussions on dutch presses make me want to record a little lesson on analyzing machines and post it here so people can see how a mechanical/civil engineer would examine the press--kind of kike Kahn Academy.  Maybe I'll do that...someday.
If only I could make cheese as well as I grow a mustache...

Offline Boofer

  • Old Cheese
  • *****
  • Location: Parkland, Washington
  • Posts: 4,226
  • Cheeses: 204
  • Contemplating cheese
Re: My 4-pulley dutch press
« Reply #13 on: January 29, 2013, 07:41:22 AM »
Yeah, my press does go up to that existential "11". ;)

-Boofer-
Let's ferment something!
Bread, beer, wine, cheese...it's all good.

Offline Tom Turophile / CheeseStud

  • Mature Cheese
  • ****
  • Location: Atlanta
  • Posts: 171
  • Cheeses: 3
  • Default personal text
Re: My 4-pulley dutch press
« Reply #14 on: February 20, 2013, 11:07:20 AM »
So I rebuilt the press, using a 2x3 to replace the piece that broke...and it broke, too.  Its weakness is from where the screws go through; since the weight pulls up right through there, it bows and breaks.  Frustrating.
CheeseStud(.com coming soon)
4 store-bought cow's milk mozzarellas, 1 rather rubbery raw cow milk mozz, cow's feta that melted, 0 ricotta