Is anyone using the Cheesemaking.com 6" stainless mold with ~1000 lb (35 psi) pushing down on the curds?
Link:
http://www.cheesemaking.com/store/p/32-Stainless-Steel-Mold-1.html (http://www.cheesemaking.com/store/p/32-Stainless-Steel-Mold-1.html)
I guess I'm more interested to know that someone is using this mold with around this kind of force, but I would also like to know how one would calculate the forces pushing on the inside walls?
The mold is open on both ends, but I guess it will need to be secured down in a way that essentially makes it closed on both ends.
Is it correct to think that if my way of securing the mold down is minimal (maybe a bungee), that the curds will squeeze out the bottom before the mold would ever rupture? Will the curds squeeze out the bottom with 35 psi? How do people with open ended molds address this?
It is 5.75" diameter x 7" high. Thickness is ~ 1 mm (0.04").
I put 300 lb of weight on a 6" mold made from a flexible plastic material. It seems like a no-brainer that the stainless should not have a problem with 3.5 x this, but if there is a way to confirm it before I throw some curds in and try it out, I'd like to do that.
OUCH! That is some price!
http://www.ullmers-dairyequipment.com/Cheese-Molds.html (http://www.ullmers-dairyequipment.com/Cheese-Molds.html)
They are used commercial dairy molds and proven themselves. They have a few sizes left but you could probably get two for that price! Just cut your own follower from those nylon cutting boards from the dollar store.
WHY are you using 300 pounds? It is highly unlikely that you will ever need anything near 1000 pounds or 35 psi.
Yes, your curds will squeeze out the bottom.
Cut a follower for the top and bottom if you are worried about the curds coming out. It will give you a buffer space. I think it drains better that way too but that could just be me.
Sailor -
the 35 psi for cheddar comes from Margaret Morris' book (actually 40 psi in her recipe), recipes from this forum, and from a person who's spent lots of time at different cheese makers. There seem to be quite a few people on this forum who press at high pressures. Its not difficult for me to get to that level of psi with a pneumatic cylinder, so I I'd like to try it.
Deejay -
I don't think it would, but I was worried about the mold rupturing if I pin it down securely and then apply the high pressure. I like the idea of putting a thick follower under the mold (I guess after the first 30 minutes of light pressing so that there is room) if it works. But wouldnt the curds still force the mold to lift up the same way they do when the mold is laying flat o the board?
Where do people get the really thick white boards? I have a bunch of the 1/4" ones that I store wheels on in the fridge. I'm not sure where the 1.5 -2" type stuff comes from.
JL - Margaret Morris is coming at this from an industrial cheese perspective. Especially for the hobbyist or small producer, there are many other ways to achieve a well pressed cheese. I make at least 2 different batches (38 gallons per batch) of cheddar every week - Cheshire, Derby, Lancashire, Gloucester, or Wensleydale. My presses are certainly capable of 35 psi, but I never press over 5 psi. In fact I routinely do cheddars with just 2 psi. The trick is to keep your curds warm then hoop quickly after milling and salting. In a commercial environment, curds are often stone cold by the time they get to the press, so it takes more force.
I spent some time in Italy last Summer and was fortunate to visit a traditional Parmesan maker. They scoop the curd mass out of the vat in cheesecloth and place 150 pounds or so in wooden hoops (literally hoops). Then they place a simple 10-20 pound flat weight on top of the cheese cloth and let it sit. No press, no followers, and no elaborate system of weights. And the cheese has been coming out perfect for generations. That experience led me to rethink some of my own pressing strategies. Cheese will aggressively fuse together if you give it the right conditions.
J - The 1/4 inch ones will work fine cut two for each top and bottom. I think the dollarstores here have cheap 1/4 inch or a bit pricier 1/2 inch. You shouldn't need more than that.
Ed - Now you see how I can press cheddar with just a few cans of tomatoes and get a good press. It has to be the the tall bucket holding in the heat. Or the pressing under the heated whey when I do that.
I recently did my first Double Gloucester which I pressed at ~575lbs (13.7psi). That was to see if I could.
Most of the cheese I have been doing over the past couple years has been using 5lb to 25lb. I think rarely I would ever have to repeat the big pressure my Double Glouc received. Just so you know.... :)
Keeping the curds warm (in the pot and/or using the seed mat...thanks Sailor!) is a major part of getting a tight knit.
-Boofer-
You can also use a table lamp which radiates alot of heat.
Yes Debbie. I humbly bow to the sage wisdom of the Tomato Can Queen. ;D
Quote from: Sailor Con Queso on March 23, 2012, 01:25:03 PM
Yes Debbie. I humbly bow to the sage wisdom of the Tomato Can Queen. ;D
(http://deejaysworld.net/yabbfiles/Smilies/LaughDog.gif)
Ah Ed I like that! I will take that as a compiment. My Italian Mama (God rest her soul) would love it! You do realize I did that originally to keep my cans from falling over and to keep the whey from spilling onto my counter and floor right? It just "happened" it worked great for pressing and it took
you to figure out why. The heat retention angle never occured to me!
High five my dear friend!
(http://deejaysworld.net/yabbfiles/Smilies/hugShake.gif)
Yes DJ, that was a "compiment" (whatever that is). ;) I learned a lot of respect for Italian Mamas last Summer. I loved the hill country in Tuscany. We ate on a couple of rural farms and man they do know how to cook. The French are all about procedure and technique while the Italians are into simple, earthy, understated, natural foods. They approach their cheeses the same way.
It's still about PSI, not weight. :) ;) :D
I soooo envy your trips to Italy! I would love to go one day and see where my grandparents and aunts came from. Only my mother and one uncle were born here so I always felt so close and drawn to "the old country." They were all good cooks but not one would ever admit it. Just a little of this and a little of that. That is also my appproach to cooking, cheese and sausage making. I know it drove you nuts at first but we didn't have the internet or this place when I started it was just trial and error.
I have learned alot about the whys of things here and it has been very helpful and I always enjoy your posts and techniques. One day you, me, Pav and a few others with a bottle of wine, a few sticks of pepperoni and a block of aged provalone ...
Quote from: jlewis92 on March 22, 2012, 09:08:45 PM
I guess I'm more interested to know that someone is using this mold with around this kind of force, but I would also like to know how one would calculate the forces pushing on the inside walls?
The formula for this is given here: http://www.engineeringtoolbox.com/stress-thin-walled-tube-d_948.html (http://www.engineeringtoolbox.com/stress-thin-walled-tube-d_948.html) - Hoop stress
σh = p d / 2 t
To make sense of this, different materials are rated by the amount of stress (σ) they'll take before they start changing shape. This is called yield stress (σy). To make the equation more useful, we can juggle stuff around so that it looks like
F = 1.57xtxDxσy
the yield stress for 316 stainless steel is 40,000 psi and for HPDE is 2,175 psi
soooo for your dimensions of D=5.75" & t=.04"
F = 1.57x.04x5.75x40000 = 14,444 lbs
meaning that the form will maintain it shape (and not break) at least up to 14,000 lbs. of applied force (weight).
We can also see why the HPDE forms are much thicker since the material is almost 20 times weaker than stainless.
Hope this helps.
Now the question is "can a physics major make good cheese? ". I love it!
14,444 lbs....seems like enough ;D
Thanks for all the replies! I know there is more than one way to skin a cat, and pressing at lower psi works based on all the input here, but since I can go higher psi, I want to try it. Why not replicate the industrial process if its possible and convenient?
There isn't anything that prevents me from using my press at lower psi's, so I can always dial it down later. But I do want to experiment and find what works best for me.
JimP - thanks for the formula on hoop stress.
- Jeff