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GENERAL CHEESE MAKING BOARDS (Specific Cheese Making in Boards above) => EQUIPMENT - Forming Cheese => Topic started by: Just Plain Fred on September 04, 2013, 11:06:23 AM

Title: pneumatic press questions
Post by: Just Plain Fred on September 04, 2013, 11:06:23 AM
Hello all,
  I have recently found a source for farm milk, and have been making mozzarella .. I would like to now try some hard cheeses (cheddar) as well.The presses that i have looked at ...wooden contraptions, and some stainless steel types,are interesting but not what I'm looking for.  Being a "techie" and having a pretty good shop, thinking that i could do better... Question:(s)

 1. What would be a good diameter pneumatic cylinder to look for ? Don't know what ultimate pressure ( lbs) should end up at for hard cheese . My air compressor  will only put out about 125lbs psi.

 2. As far as the cylinders "stroke" I'm thinking about 12 inches would do...

 3. I have seen some "Home Builts" on this forum ..they seem to be all over the place varying in diameter and stroke length.

 4. So far I've  found some "Non repairable Stainless Steel " types and am looking at a 2" diameter Cylinder \ 12" stroke unit ( about $120USD's)

Any input would be appreciated   ...Thanks ... Regards Fred
Title: Re: pneumatic press questions
Post by: mjr522 on September 04, 2013, 02:59:10 PM
I briefly looked into putting together a pneumatic press.  I stopped when our lab director said in his experience pneumatic cylinders (at least the lower price ones I was interested in) leak quite a bit (I don't know what experience he has, but I'm sure he's got more than me).  Because in pressing cheeses you need sustained pressure (6 hours is pretty common, 12, and even 24 are not uncommon), a leak in the cylinder, depending on the size, could lead to the compressor running frequently--not necessarily a problem, but possibly depending on your situation.

1. As for cylinder size, it depends on what you're looking to make.  I've seen pressure called for from 2 psi upto 40 psi, but it seems that around 6 psi works for most of the cheeses people make.  I think I'd figure out what size cheeses I was going to make, determine the maximum pressure for the cheeses I'm interested in and size accordingly.  If I were just winging it, I'd shoot for 10 psi on the biggest mold I plan on making.

2. A 12 inch stroke is pretty big for single cheese.  If you figure that from a hand pressed pile of curds to a solid cheese you lose about 1/2 the height (I'm not sure that's exactly right, but I think it's close to what I observe), a 12 inch stroke could be used to make a 12 inch tall cheese in a 24 inch tall mold.  If you plan on stacking and pressing multiple cheeses at once, a 12 inch stroke could let you, depending on your mold configuration, press a 4 or 5 cheeses that are each 1 1/2 - 2 inches thick.  Either way, that's a lot of cheese.

Hopefully, someone with experience with a pneumatic press will give you some insight...
Title: Re: pneumatic press questions
Post by: jwalker on September 04, 2013, 03:43:45 PM

 1. What would be a good diameter pneumatic cylinder to look for ? Don't know what ultimate pressure ( lbs) should end up at for hard cheese . My air compressor  will only put out about 125lbs psi.

 

Any input would be appreciated   ...Thanks ... Regards Fred

Just remember to calculate the area of the cylinder , 125 psi is way more than enough for most cheeses depending on cylinder size.

A 2 inch cylinder would have an area 3.14 inches , at 50 psi , that would be equivalent to pressing straight downward with a 157 lb weight.

A 4 inch cylinder would have an area of 12.56 in. , at 50 psi , that would be equivalent to pressing downward with a 628 lb weight.

When you double the diameter , you quadruple surface area and the total downward pressure.

So you would take the total down pressure , and divide it by the surface area of the cheese , 628 lbs , on a 6 in. cheese (28.27 sq. in.) would be 22.21 psi on the cheese . (628 divided by 28.27 = 22.21 psi.)

The bigger the cylinder , the less air pressure you would need to get a set pressure on the cheese , the larger cylinder would of course use more volume of air.

A stainless cylinder kept properly lubricated with a food grade oil  shouldn't have any leak problems , I would use a check valve in the delivery line as close to the cylinder as possible tho , and a regulator with as small a pressure differential as possible , they're usually about 5-10 lbs , at least the one I work with.

I would think 12 inch stroke would be plenty for the average guy.

All above values are approximate.
Title: Re: pneumatic press questions
Post by: FRANCOIS on September 04, 2013, 08:08:14 PM
JWalker is right.  You need ot take into account the volume your compressor can produce. 
Title: Re: pneumatic press questions
Post by: Just Plain Fred on September 05, 2013, 11:27:06 PM
Hello All,
 OK.... thanks for the input. I'm putting together the list of materials for this project, and have ordered the 2" pneumatic cylinder.. I have "firmed up" the design , and will start as soon as time permits . I will post a "pic" when finished ...Think that my design will take these "home presses" to a new level of adaptability.  Thanks again .... Regards Fred
Title: Re: pneumatic press questions
Post by: Just Plain Fred on November 03, 2013, 07:00:19 PM
Hello All,
  Well it's taken me awhile but i have finished my press ... I have reviewed what i consider the best features of the "presses" that have been posted, and incorporated them into my design... Here are of a few comments

 1. The tray ( food grade) is recessed and removable , with internal drain for hose attachment.

 2. This design lets the user choose and adjust for the height of any form ( hoop) combo.

 3. The machine threaded rods have been "Tapped " bottom and top ..so you could add any length rod to this ( for multiple form stacking)

 4. Can be easily disassembled for storage ... (Remove two lower threaded rod bolts)

 5. The setup does not leak ( much air... new parts)..( still testing as to the rate ) and am modifying an old fire extinguisher to run this rig . The ones i have can be filled to 140 PSI ( limit of regulator and valve) 

Can someone give a pressing schedule for Cheddar ( in PSI required...not dead weight ) so i can figure how much i need for my hoops\ forms square inches.

Thanks in advance ...Regards Fred

PS: trying to post pictures ...so far ..only one?...Help!.. Sorry about the "sideways pic" can someone please remove ..Ive tried with no results.
Title: Re: pneumatic press questions
Post by: mjr522 on November 03, 2013, 09:43:03 PM
That's a nice looking press.  I'll be interested in hearing how it works out for you.  40 psi is what I have read for cheddar.  That's pretty high compared to other cheeses.
Title: Re: pneumatic press questions
Post by: Just Plain Fred on November 03, 2013, 10:17:37 PM
Mike,
 Thanks ... Do you know if there is a specific schedule for cheddar? I have read that you start at some lower weight and after a time you progress to the final weight ... This is what i think is a problem ... Most recipes give some type of schedule for "dead weight" and don't say for what size mold to use ... Maybe this is because everyone knows what the size is for what type of cheese, and for how many gallons ...Me Ive no clue.. Thanks for the response... Regards Fred

PS: I'll post results as soon as i can "Firm up" (Cheddar joke) the recipe
Title: Re: pneumatic press questions
Post by: mjr522 on November 03, 2013, 11:54:30 PM
I don't know a schedule for PSI.  I'm not terribly good at following those schedules, any way.  I think you'd be fine, if you want to move up the pressure, to just press at some lower level for 15 minutes, flip and increase pressure for another 15, and keep it up until you get to the 40 psi.  Maybe someone else will give you something more concrete.
Title: Re: pneumatic press questions
Post by: Digitalsmgital on November 04, 2013, 01:20:01 AM
Those pictures = cheese porn

12 PSI 45 minutes

18 PSI  120 minutes

40 PSI 288 minutes
Title: Re: pneumatic press questions
Post by: cowboycheese on November 04, 2013, 01:38:48 AM
What material, if I might ask, did you use for the draining tray and followers? I haven't found the right stuff around here (yet) - it is all way to soft and pliable (standard HDPE cutting board stock).

Let us know how it test out and if you wouldn't mind sharing what your parts list was. The simplicity and expandability of your frame design is really cool and worth a cheese!
Title: Re: pneumatic press questions
Post by: Just Plain Fred on November 04, 2013, 01:58:48 AM
"Cowboy"

 Hello... The Plastic (1" HDPE type cutting board type) was from  TAP Plastics  (http://www.tapplastics.com/product/plastics/cut_to_size_plastic/hdpe_cutting_boards/346) You can order and have whatever size you need ... I only at this point have my hand drawings and notes of the construction process .. If you want i will try to put together a parts list ( vendors) and clean up sketches that Ive made ... Maybe others would be interested ... Guess if you don't have access to machine tools ( Metal lathe, Welder, etc.) you could use my drawings and bring them to a local "fabricating metal shop " Have no idea what they would charge for such a project... took me several weeks ( hours that i could spare ) Thanks for your comments...Regards Fred
Title: Re: pneumatic press questions
Post by: Just Plain Fred on November 04, 2013, 02:36:38 PM
Those pictures = cheese porn

12 PSI 45 minutes

18 PSI  120 minutes

40 PSI 288 minutes

"Digital"

  Hello.. Thanks for the reply and "Info" ... This is the confusion that i was trying to figure ...I'll try to explain my question ( Math not my strong point)

 1. In your example the PSI is for what size mold\follower? If i use a 4" diameter follower, this will translate into about 12.5 square inches ( follower area).. If i apply the first pressure 12PSI... Either you have to multiply this (12PSI) times 12.5 or an initial dead weight of 150#.. Or the other way ...divide the 12PSI by the square inches (12.5) of the 4" follower ..Or .96# So ...

 2. If you use the max PSI you give of 40# it's either 500#'s or 4#'s

 3. In my figuring you need to give the Dead weight for a given surface area ...and you would end up with a number for the actual PSI determined by the square inches of the follower... Hey what do i know?...can't even remember HS math class. To simplify... the pressure applied to a 4" mold ..can't be the same for a 8" mold

Any one have any thoughts about this?


Regards Fred
Title: Re: pneumatic press questions
Post by: Sailor Con Queso on November 04, 2013, 03:14:47 PM
Dead weight changes, but PSI is a standard that doesn't change from hoop to hoop. While you should use a different "weight" on a 4" or 8" hoop, the PSI remains constant.
Title: Re: pneumatic press questions
Post by: jwalker on November 04, 2013, 03:21:30 PM
First of all , let me say that's an impressive looking press.

Kudos and a cheese for that.

@120 PSI air pressure , a 2" diameter will exert just over 360 pound of force on your cheese.

A 4" cheese will have a surface area of about 12.5 inches.

So 360 pounds divided by 12.5 is just under 30 PSI exerted on a 4" cheese.

Remember , when you double the diameter , you quadruple the surface area , so an 8" cheese will only get 7.5 pound per square inch (PSI).

You're going to need some serious air pressure or a larger cylinder to get anywhere near 40 PSI on an 8" cheese.

You could use bottled nitrogen and quadruple the pressure to the cylinder , if it is rated for that kind of pressure.

It's always better to have a bigger cylinder than you think you will need though.
Title: Re: pneumatic press questions
Post by: Just Plain Fred on November 04, 2013, 04:19:58 PM
Dead weight changes, but PSI is a standard that doesn't change from hoop to hoop. While you should use a different "weight" on a 4" or 8" hoop, the PSI remains constant.

"Sailor",

 Hello... Guess I'm missing something... ( block of Cheddar brain)  Let's take two extreme cases... If you had a 1" rod pressing down at 100 PSI ..well simple 100 psi... Next case you have a manhole cover (36") with the same 1" rod at 100PSI .. The 100PSI would be distributed over the square inches of the 36" cover (1017sq in) Am i over thinking this?...Regards Fred
 
Title: Re: pneumatic press questions
Post by: Just Plain Fred on November 04, 2013, 04:23:43 PM

@120 PSI air pressure , a 2" diameter will exert just over 360 pound of force on your cheese.

A 4" cheese will have a surface area of about 12.5 inches.

So 360 pounds divided by 12.5 is just under 30 PSI exerted on a 4" cheese.



 jwalker

Hello... Thanks Much for your responses ...Yes i agree (i think) Then why isn't this weight given for the different size molds? Wouldn't everyone need to no this before you end up with too low a press weight... Regards Fred
Title: Re: pneumatic press questions
Post by: jwalker on November 04, 2013, 05:01:47 PM
Fred , don't get too concerned with high press weights , I am fairly new at this , been making cheese for about a year , and I started with R Carrolls book which reccomends  pretty high weights.

All of my original hard cheese came out very hard and dry , as well as bitter.

So I reduced my weights considerably , and my latest versions are coming out very nice with about 3-4 PSI , even Cheddar.

I think one of the things that contribute to this is the fact that I use store bought milk , the curds tend to break up very small and lose a lot of whey in the process , so less press weight results in retaining more whey , for a softer  more palatable cheese.

I think there is more to press weight than some think , type of milk , size of curd , washed curds , temperature of wash , temperature of curds when pressing , time in the press , salting methods , and just plain old personal preference.

I think you'll find your press will do the job.
Title: Re: pneumatic press questions
Post by: artguy on January 05, 2014, 05:50:35 PM
Just Plain Fred 

Would you be willing to share the dimensions of the thread and square stock parts you made as well as the size of piston you used?   Love your press.  A friend of mine is a machinist and we were looking to fabricate a press.  Your design is very intuitive and impressive. Please?............:)
Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 05, 2014, 07:24:16 PM
artguy,
 Hello... would be happy to help

1. Thread size is a 1"X 8 TPI ...With drilled and tapped 1\4" X 20 holes on the ends of the "rods" ..I used  1" hot rolled steel stock ( couldn't find cold rolled 1" stock at the time) ..Note  cut the threads (Lathe) on the "Loose" side ( approx 50 % engagement)  so they can be "spun" with just a "quick flick" also file the threads flat with a file when finished so you don't cut yourself when spinning the SS nuts.

2. The Square tubing is standard 2"x 2" x .180 stock  2" will work best for "Air Cylinders in the 2" diameter size.

3. The double stroke cylinder is a "SPEEDAIRE"  2" x 12"

Post back if i can be of any further help...Regards Fred

PS: I have made a few "Mods" since ... i will post a new pic as soon a i can find my camera... Added a  more sensitive pressure gauge ...etc
Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 05, 2014, 07:58:17 PM
artguy,
 Don't know how to add the "pic" in my original post so this is the only way i can

1.  Added SS washers on the top and bottom so the nuts don't dig into the tubing.

2.  The pressure gauge is a 60 PSI unit as the multiplication factor is X3 for a 2" cylinder , allowing for a max force  of Approx 180psi on the ram... should be more than enough for "Cheddar" using a 4" or 6" mold... If not, i can always swap it out for one of higher value and put more initial pressure from the main regulator

3. Pay attention on how you hook up the 3 way valve ... i had reversed the "P"(Input)  and "R" ( Exhaust ) and the valve leaked air  A & B are ( up and down) outputs
Title: Re: pneumatic press questions
Post by: artguy on January 09, 2014, 02:31:45 AM
How much would you charge if someone were to commission one that has a fixed height with no threaded stock and a cylinder with a shorter stroke?
Title: Re: pneumatic press questions
Post by: artguy on January 09, 2014, 02:36:13 AM
Wanted to clarify.  I am having a hard time getting scheduled into our metals shop.  What I really need help with is fabing the metal structure and cutting board for the whey.  Then I have no problem getting the parts and assembling it.  Found all the pneumatic parts you listed previously.
Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 09, 2014, 02:55:54 PM
Wanted to clarify.  I am having a hard time getting scheduled into our metals shop.  What I really need help with is fabing the metal structure and cutting board for the whey.  Then I have no problem getting the parts and assembling it.  Found all the pneumatic parts you listed previously.

artguy,
 
 Hello... I used "threaded rods" in my design because.... When using open end molds my thought was to secure (hold down) the top of the mold with the upper bar. This would prevent the curds from trying to squeeze out ("lift up" ) the mold under heavy pressure. I am an "old retired guy" and only reckon that i have only a few more years left on my contract ( threescore and ten) So... i don't "hire out" any longer. Your best bet would be to find a local shop to "cut" (thread drill and tap) the bars and mill out the tray ... Regards Fred
Title: Re: pneumatic press questions
Post by: artguy on January 09, 2014, 10:54:03 PM
no worries, understandable.  Could you tell me this.  If I were to make the press a fixed height what would you suggest for the interior dimension for standard sized molds?  Keeping in mind I would be using 2" stock, what length stroke should I get when I purchase a cylinder?  Thanks for answering all these questions from a beginner.  If I go to a fixed height press I will have a better chance of being able to make it at school as it will not require as much advance machining processes.


Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 09, 2014, 11:48:19 PM
artguy,

 Hello... I'm a beginner also ...my best best guess answers...

 1. For interior size .. this all depends on the mold height. I have 8" ( 4" and  6" diameter ) I've seen some that are only 4" in height ...So you have to be the judge as to which type of mold height your looking at ... If your going to use a single 4" high closed bottom mold ...i would go with a 8" to 12" interior height

 2.  As to the ( Dual ) cylinder size ... there is not much difference in price in a 2" cylinder whether the stroke is 8 " or 12" The 2" cylinder diameter is a nice compromise as it gives an (Approx)  3 x   multiplication over your input pressure, and doesn't use much air. Also...  fits on to a 2" square tubing stock with only a slight "Mod" of the connecting nut.

 3. The frame still would require welding for the base ...

 4. I would wait and build the "Adjustable" version from the "Geko" ... this way you won't "out-grow"  it down the road when you want to make a different type of cheese ...Or want to press out a wheel bearing...Regards Fred
Title: Re: pneumatic press questions
Post by: artguy on January 10, 2014, 02:41:58 AM
Thanks for you help Fred.
Cheers

Title: Re: pneumatic press questions
Post by: artguy on January 12, 2014, 03:57:01 PM
quick question for you fred, what is the additional length you have added there to the 2" square stock to accommodate the regulator and valve?

Cheers

Title: Re: pneumatic press questions
Post by: jwalker on January 12, 2014, 04:36:46 PM
artguy, ...Or want to press out a wheel bearing...Regards Fred


LOL!! ;D ;D ;D
Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 12, 2014, 04:53:42 PM
quick question for you fred, what is the additional length you have added there to the 2" square stock to accommodate the regulator and valve?

 artguy,
 
  Hello... The Base is 16" x 16".... and the top member is 21" in  length...
Regards Fred...

PS: One other thing...The "Holes" drilled into the upper bar are 1 1\4"  and then fitted with some "Bushings" made from the 1" cutting board stock. They are not visible on the picture..there inside the 2" x 2"  and attached with 6x32 flathead screws..This lets the upper bar "Slide" easily up and down the screw threads without jamming.

Title: Re: pneumatic press questions
Post by: artguy on January 13, 2014, 09:22:46 PM
Here is my scale model minus the cylinder!

Title: Re: pneumatic press questions
Post by: John@PC on January 13, 2014, 10:34:22 PM
I looked at the picture before reading the text and was thinking "what tha...? :o"  Very "architectural", not to mention artistic.  Good luck on the project.
Title: Re: pneumatic press questions
Post by: artguy on January 13, 2014, 11:12:58 PM
Thanks.  Incorporate the extra length on the side like you did.  Good idea for making space to mount the regulator and valve.  Thanks for letting me borrow the idea.  Going to make it fixed height.  WIll allow me to make 1lb-5 lb wheel.  Plenty for me considering all my other hobbies and the fact that we just had our first child.  Needless to say.  The budget wont allow me to make massive quantities of cheese. Thanks again for the help and inspiration


Title: Re: pneumatic press questions
Post by: artguy on January 14, 2014, 03:32:07 PM
What "type" for valve do I need to get to control the doul acting piston.  There are a lot of different types. 5/2, 5/3, 2/3, 4/2 etc...  Some have 4 ports and others have threes.  Some are listed as two way.  UG!  So confusing.  Any guidance?  Sont need anything quite like the hand valve youhave.  Just going to have a switch and use the flow control elbows on the air hoses.


Cheers
Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 14, 2014, 06:52:25 PM
artguy,

 Hello... OK I'll try to give a quick "Splain it to me lucy"..
 
 The "Air valve " that you need to run this type of cylinder (Dual stroke)  is a Valve that has three positions...
1. Off Center position ...Need this so you valve off the air supply from cylinder... various reasons

2. "Up" to make the cylinder retract ...either "A or B " outputs

3. "Down" to advance the piston to press mode. 

PS: Use  the valve....it's a "no brainer" and does not cost much

Regards Fred

Here is a link to a good place to look for a valve and assorted parts Parts (http://www.automationdirect.com/adc/Shopping/Catalog/Pneumatic_Components)
Title: Re: pneumatic press questions
Post by: artguy on January 14, 2014, 07:41:56 PM
ok so a 4 port three position valve?  1/4" npt?


Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 14, 2014, 09:21:38 PM
Artguy,
 
 Hello... Yes ...if you want 1\4" ports....Regards Fred
Title: Re: pneumatic press questions
Post by: artguy on January 15, 2014, 04:14:47 AM
Sweet thanks!  Your going to have to send me your mailing address when this is all done so I can send you one of my hand made mugs as a thank you!  You're awesome!


Title: Re: pneumatic press questions
Post by: artguy on January 15, 2014, 06:26:07 PM
Cool.  Thanks for the website.  Great resource.  Good prices too.  I was looking on ebay instead but I am buying everything from these guys.  Anywho I noticed you have a seperate pressure gage on the top of the cylinder.  Is that because the combo one you have on the incoming has a range of 20-130psi?  Trying to figure out if I want to buy that one from automation direct or spend the extra money and get a wider range on the low end.  I am wondering that if I am using a portable tank for my air source, and I prime it to say 6 psi and open the incoming regulator to its minimum 20 psi, the 6 psi will pass through and exert 6 psi onto the cylinder.
Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 16, 2014, 12:01:18 AM
artguy,

 Hello... The pressure gauge ( 0 > 60 PSI ) that i used was to make it easier to apply the correct "PSI" to the mold ..The 20 > 130 PSI regulator is too course for fine adjustments . Example...  For a 4 " mold \ with 4" follower = 12.5 sq " .... Typical press schedule ( so I'm told for Cheddar) ...12 # 45 minutes, 18 # 120 minutes, 40 # 5 hours.... Would be translate (for a 2 " cylinder)...

 1.  4 # 45 minutes

 2.  6 # 120 minutes

 3.  13 # 5 hours 

 You need to have more pressure in your storage tank ... Say 100 PSI  (so the regulator can work) .. this is important so the regulator can maintain the set pressure as the cylinder extends as the cheese ( curds)  compress ... This is the main advantage of having this type of setup... You know that the pressure is always ( constant) what you set it to.... I also use a portable "Air Tank" pressurized to approx 125 PSI.. The regulator won't work if there is not enough input pressure....

Hey !... send me a ticket ...i will work for Pizza and beer ;)...Regards Fred
 
Title: Re: pneumatic press questions
Post by: artguy on January 16, 2014, 01:40:09 AM
so you discovered that you needed a pressure guage for finer tuning adjustments on the cylinder for pressures under 20psi.  Is the pressure gauge only measuring the incoming psi on the cylinder and you are adjusting accordingly on the <20<130PSI regulator? 
Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 16, 2014, 02:09:50 AM
artguy,

 Hello... Yes... you are correct ( although the regulator gauge measures the output not the input )  ... I have the 60# pressure gauge setup on the "advance piston" side ...so i can fine tune the "Main Input Regulator" ...It's not sensitive enough  (small gauge) can't read low pressures.. So with a 60#(  2 1\2 "full scale )  gauge i can see\set small pressures required . ..Regards Fred
Title: Re: pneumatic press questions
Post by: artguy on January 16, 2014, 02:34:04 AM
cool.  So I am going to purchase this one that is 20-130 psi.  And since the input doesnt matter, I can put adequate pressure in the portable tank, add a scondary dial on the cylinders input and turn the adjustment knob on the regulator until the secondary dial reads the appropriate psi.  So even the the regulator is rate 20-130 I can puch through say 6psi?

the model number for it on automation direct is

AFR-2233-M



Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 16, 2014, 11:57:27 AM
artguy,

 Hello.... Yes ..I have done this testing the setup. Just back the regulator off all the way and then advance it slowly. With the 3 way valve set to  "Advance  Piston" watch the 2 1\2 " gauge ... Don't forget to pressure test your setup ( all positions) once everything is connected ...let it under pressure overnight (Activate cylinder to press on something..Then  valve lever to center...Off) .There should be no discernible change in the pressure as read on the gauge... Remember that when actually pressing that the air supply needs to be connected and the valve set for "Press mode" so that the regulator can adjust itself as the curds squeeze down... One other thing...you will (might want) need to switch around the input \ output of that regulator.. Mine came with the small gauge on the wrong side for my application, Not sure about the one you have  ... can be done with a screwdriver...

Regards Fred
Title: Re: pneumatic press questions
Post by: artguy on January 18, 2014, 02:34:09 AM
Well all the parts are ordered and on their way! The portable air tank is finished as well.  I ordered a coiled polyurethane hose with quick disconnects to connect it to the regulator.  Ended up finding a small regulator with trap on ebay that new and goes 0-160 psi with a fairly detailed dial. Now I am having the darndest time finding a fitting for the end of my cylinder rod.  they said it is a #8 5/8 x 18 unf.  Would love to have like a closed in coupler or something that looks like the shape of an upside down thumb tack.  Any thoughts?
Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 18, 2014, 12:47:19 PM
artguy,
 
  Hello... The thread on my cylinder ( rod) is 1\2 x 20 UNF and the "coupler" was machined from 304 stainless steel ... the large  piece was from a 2 1\2 " round stock, ( see previous pic's #20 ) and the connector from 3\4 " round stock drilled and tapped for the 1\2 x 20 UNF  thread. The large 2 1\2 " round is fastened to the 3\4" piece on one end with a 1\4X 20  SS flathead screw..could be welded ..figured best to attach with the screw so i can switch to a larger than 2 1\2" if needed... Regards Fred
Title: Re: pneumatic press questions
Post by: John@PC on January 20, 2014, 12:01:30 AM
The portable air tank is finished as well.... Now I am having the darndest time finding a fitting for the end of my cylinder rod.  they said it is a #8 5/8 x 18 unf.  Would love to have like a closed in coupler or something that looks like the shape of an upside down thumb tack.  Any thoughts?
Fred has probably the "best" solution but if you're on a budget if it were me I would get something like a 1/2" thick square aluminum bar, maybe 2" x 2" or so and drill and tap a hole in the center.  You can screw this "pusher" onto the cylinder rod end and use a jam nut at the top to secure it.  If you're concerned with having exposed threads and hole just fill in with silicone.

That said that is some nice artwork on the air tank  ^-^! 
Title: Re: pneumatic press questions
Post by: artguy on January 28, 2014, 04:30:18 PM
Howdy Fred
I tested out the pneumatics last night.  The gauge on the air tank registered a loss of 2.5 psi over the course of 12 hours.  Is that something to worry about or is that pretty good?  Also are air cylinder rods usually pretty finicky if they don't get to plunge straight down?  I notice that if Mine gets pressed slightly to the side it looses its seal and air just blasts out the position lever.

Title: Re: pneumatic press questions
Post by: jwalker on January 28, 2014, 05:07:09 PM
Howdy Fred
I tested out the pneumatics last night.  The gauge on the air tank registered a loss of 2.5 psi over the course of 12 hours.  Is that something to worry about or is that pretty good?  Also are air cylinder rods usually pretty finicky if they don't get to plunge straight down?  I notice that if Mine gets pressed slightly to the side it looses its seal and air just blasts out the position lever.

It might be a good idea to put a small amount  of lubricant in the cylinder , maybe some vegetable oil , if the seals get too dry they tend to leak.
Title: Re: pneumatic press questions
Post by: Just Plain Fred on January 28, 2014, 07:03:53 PM
artguy,
 
 Hello.. There is no way ...other than pressure testing and using a "leak detecting fluid" ( you can use "Windex" in a pinch )to ascertain where the "leak" is ... if you are not using a gauge on your setup ( see pic in # 20) As i have previously stated with pressure on the cylinder and pressing on something ...i have no discernible leaking ( overnight tests with valve center position .."Off")..I have not tried to "press sideways" on the cylinder rod. ( also i have a different cylinder) Make sure that you have the "Valve" connected correctly .... the "P" is the pressure input, A & B are outputs...If you connect it some other way ...it will leak. If everything is OK there should be no air leaks....    Regards Fred

PS: If you have enough air capacity ( your tank)  loosing a few pounds of pressure won't be a problem, as the regulator will adjust for this anyway.
Title: Re: pneumatic press questions
Post by: John@PC on January 29, 2014, 11:28:45 PM
PS: If you have enough air capacity ( your tank)  loosing a few pounds of pressure won't be a problem, as the regulator will adjust for this anyway.
Ditto that.  If the regulator pressure is dropping then that would be something to check out.  There will always be small leaks in the system (cylinder seals primarily) but a loss of 2.5 doesn't seem unreasonable.  As far as deflection of the rod I would be willing to guess that the seal leakage occurs at the bottom extent of the cylinder?  Are you just letting the cylinder extend fully and then pushing the rod sideways?  If so that's a no-no unless you have a cylinder with guide rods or linear bearings.  It looks like you have a long cylinder and you should be fine if you don't extend beyond 2/3 of the travel.
Title: Re: pneumatic press questions
Post by: artguy on February 06, 2014, 01:08:12 AM
ok here it is on its maiden voyage!  Still waiting on getting my drip tray for the whey cut on the cnc.  But here it is and its working great!  Thanks for all the help Fred!!!

Title: Re: pneumatic press questions
Post by: H-K-J on February 06, 2014, 01:49:47 AM
Now that is nice 8)
ACTU  ;D
Title: Re: pneumatic press questions
Post by: cowboycheese on February 06, 2014, 02:06:50 AM
Great job! I'm getting the bug myself and hope to start my own build as soon as the weather warms up a bit in my workshop. I've found it hard to weld when it is -4 out there.

A cheese for you!
Title: Re: pneumatic press questions
Post by: H-K-J on February 06, 2014, 03:26:30 PM
I've found it hard to weld when it is -4 out there.
I agree, It is -15 deg F. with a wind chill at -33 SUCKS!!!  :(
Title: Re: pneumatic press questions
Post by: cowboycheese on February 20, 2014, 08:51:56 PM
artguy

What did you paint/coat your frame with? It looks like 2" square steel tubing with an epoxy or powder coat on it. Nice work.
I'm debating the need for SS over cheaper steel - if I can get a good hard powder coat or similar on it then the material costs will be much cheaper.

I'm making my parts list now - can't wait for warmer welding friendly weather.
Title: Re: pneumatic press questions
Post by: John@PC on February 21, 2014, 01:02:36 AM
Great job with the press and that quality of workmanship is certainly worth a cheese.  Can't wait to see the "real" one!  ^-^.  You have patience and an eye for detail which should make you a good cheese maker.  I'm afraid I suffer from the jwalker's "look, a squirrel" syndrome.  It may not always make for the best cheese but it does make life interesting  ;D.
Title: Re: pneumatic press questions
Post by: artguy on February 25, 2014, 02:14:19 AM
Hi Cowboy.  I used the aged copper Rustoleum with 2 coats of clear gloss enamel over top.  :)

Cheers

 
Title: Re: pneumatic press questions
Post by: jwalker on February 25, 2014, 02:43:58 PM
Art , you're an Artist ! ;D

A Cheez to you for that , very nice !
Title: Re: pneumatic press questions
Post by: cowboycheese on April 04, 2014, 11:23:53 PM
artguy

Now that you have had some time to play with your new press... Is there anything about it that you think you would have done differently on the design? I'm getting ready to go get the materials.

I also asked my cousin about milling the drip tray - that might have to wait a while as his current work is a bit consuming ATM.
Title: Re: pneumatic press questions
Post by: Just Plain Fred on May 05, 2014, 10:33:59 PM
Hello all,

 Since i started this thread, thought that i should post some results ... Been making "Farmstead Cheddar"  and wanted to post some "pics" of the press in action. Also ..thought it would be of some benefit to post a few shots of my homemade "Cheese Cave"  I made this out of one sheet of 1/2" foam board and some pine "1x2"and 1x4" .. The shelves are cut down wire  20" X 12' from local "big box store" I left the bottom open to be able to "grab" the cool basement floor temps ... The "front door" is just a press fit piece of the same foam board material.. I installed a thermocouple to monitor the temps and after a few days, the temp is now at 57° F .... I'll post the results of the cut cheese after a month or so to see if the 75psi  final pressure ( 20hrs) was enough to form a nice "tight" cheddar...Regards Fred

PS: The "air tank" is a spare HVAC refrigerant recovery tank that i had and charged to approx 125psi ...seems more than enough to process with all the required "flips" of the cheese  during the pressing
Title: Re: pneumatic press questions
Post by: H-K-J on May 05, 2014, 10:54:16 PM
How do you keep the cave cool? did I miss something ???
Title: Re: pneumatic press questions
Post by: Just Plain Fred on May 05, 2014, 11:06:47 PM
H-K-J,

 Hello... I left the bottom of the "Cheese Cave" open ...My basement cement floor (Closet)  is at around 57° F ...So after closing up the cave ..the temp will stay around the floor temp ..After a few days the floor temp will stabilize the cave temp... Regards Fred
Title: Re: pneumatic press questions
Post by: Just Plain Fred on May 15, 2014, 11:12:38 PM
Hello all,
 Wanted to show the results for a "Farmstead Cheddar" ..This is a 4 gallon ( approx 4 lbs)  recipe using a 6" mold ...The pressure schedule was scaled  up ( per Jim Wallace advice...)  from the original ( 4" mold 12.5 sq ") to reflect the increased area (PSI)  for a 6" mold ( approx 28sq ") as follows

60 minutes @ 22Lbs
3 Hours      @ 56 Lbs 
24 Hours    @ 168 Lbs

The pictures show the internal cheese density ...small voids, looked just like the results from my 4" mold (2 gallon recipe) ..A few  days drying , salt washing , waxing ..and off to the cave for a month..let ya-all know how it tastes  Regards Fred
Title: Re: pneumatic press questions
Post by: John@PC on May 17, 2014, 10:07:53 PM
I'm catching up on posts and I came upon this one and did one of those double takes  ???.  I saw Fred's new cave and then H-J-K's question.  I went back to Fred's picture and realized his cave is insulated on all sides (3/4" extruded styrofoam??) but is "bottomless".   I have to give him a cheese for his ingenuity for his "passive cave" (or insulated igloo) that utilizes the cool basement floor to stabilize the temperature.