A new press

[OzzieCheese]

Well, It isn't as pretty as the original but I feel that it at least embodies the spirit of Andy's design.
http://cheeseforum.org/forum/index.php/topic,14493.30.html

And I couldn't help myself I altered a few bits.  The measurements in the plan had only a 4 time Mechanical advantage, I've upped it to 5 with a 4 MA point also created.  and Seeing as I wanted to try for a good 80 KG on the cheese I have provided anchor points for a pulley harness.

I also redid the measurements of the wood seeing as wood in the dimensions are too hard to come by in Oz.  One of the highlights of the build was finally getting to use my 2 foot 'Jack Plane' to make the Ram.  There is some therapeutic shaping the wood by hand to fit.  The ram fits into the centre slot with no more that .25mm clearance and it was so much fun making it. 
This press is made from parts of my other two: The Base plate it from Press #1, it was perfect for the dimensions on the plan.  The Secondary Pivots are from that that one as well and the main force lever is made from the RAM from #2 (smolt's press).

From full up to bottoming out on the stops the main ram moves only 1.5 inches.  The proof however will be in the 'pudding' - my August Cheddar.  One thing that I like about this is if the frame stands up to it, I can remake the main pivot longer and move the pivot point closer to the main upright and therefore providing even more Mechanical Advantage, effectively doubling the applied force on the cheese.

Time to take it apart and sand it and apply a finish of food grade protective coating and put it to work..

It has none of the grace and elegance of the original but I had a great deal of fun doing this one. 

-- Mal

[bratrules1]

Very nice!!!

[smolt1]

That looks great, but I want to see the stress test. Not enough to break anything, but enough to make a perfect Cheddar.

[awakephd]

Hey, great to see the new press! I'll be very glad to hear how it works for you.

Question: What dimensions did you use for the different parts, and what type of wood did you use. Also, when you talk about the 4x MA, are you talking just about the main lever? Don't forget that the secondary lever multiplies that by another 2x. (I'm guessing you do remember that, but you are aiming for 10x altogether.) Adding pulleys as well -- now you're up in the stratosphere.

Bob, I don't know if you saw my post a while back on stress-testing mine -- I went up to 900 lbs of force on a 6-gallon Cantal make.  It survived ... one glue joint opened up a little, but the pegs held the joint firm. Mal, work up to it slowly, listening for the creaking ...

[OzzieCheese]

Oh I'm a silly sod - I'd didn't realise that the other lever acted in the MA Calculation.  So, 4 becomes 8 and 5 becomes 10. - less engineering/workmanship induced friction   Oh and 3 times pully system - I'm thinking I'm probably not going to get that high so at this rate with a 5 Kg weigh with the 3 times Pulley advantage 5X3 = 15 X the 8-10 from the levers = 120-150Kg force at the cheese - oooh for a little 1kg Cheddar me thinks it might be a bit extreme 

The Levers and Pivots were 6 inch X 1.5inch X 1.5 inch (or close metric equivalents ).  The bases was from the another press but was about 12X12 and I modified it to have a frontal stabiliser.  The uprights are a re-engineered due to not being about get a nice 3x1 inch as per the plan but they are close at a bit over 2.75 X 1.25 inches.  The Ram is approx. 40mm x 36mm (Engineering error). but will do the job... It's all made from Tasmanian Oak - The only Hardwood I could get - I hope it's hard enough !!   

I will ratchet this one up slowly for my August Cheddar and let you know how it goes

-- Mal

[awakephd]

Now, isn't it nice to discover that you have even more force at your disposal than you realized? Seriously, there is something a bit luxurious about knowing I can take the force up as high as I care to go!

[OzzieCheese]

@smolt - I have a stress test lined up for tomorrow - just on a cork block but I'm see if I can video it and post on UtooB!  I'm going to ramp it up to 100 Kg on the cheese- probably only need 2/3 of that but it's a good safety margin.

@Andy - It's all sanded and protective coated (twice) and hardware assembled - I'll post a few images as I put it together. 

I'm really excited about this one - not that the others weren't good presses - they were -- though, I would be very happy with a nice even press and force enough to make my 'Perfect Cheddar'.

-- Mal

[smolt1]

Do you have a scale that goes that high? That would make sure you have the MA refined to more  than theoretical. Can't wait to see a video.

[OzzieCheese]

Alas no -I don't have a scale that big.  I'll post something soon

[OzzieCheese]

Here are a few of the pictures getting ready to assemble.
Twice coated - all the holes have Aluminium bushes to reduce friction all the bolts are 5/16 Steel.
The main and secondary pivots are washers inserted between the mating surfaces again to reduce friction and sideways movement.

 

[OzzieCheese]

Now for the load test.

1. NO weight but the arm - I'm going to have measure that eventually as the weight of the main lever is 1/2 Kg empty, so even with no applied weight will be sufficient to light press most cheeses.
2. Ram Verticality check - this was measured during the rest of the test and didn't move at all, same with the squareness on the main side supports - never moved.
3. I tested the 2 Kg weight but didn't need to take photos as I knew it would be fine, this is 5 Kg at the 12 Times MA point. - steady as a rock, no creaks and groans - left for 30 minutes as this is where the last two presses gave up and creaked and groaned and popped.  This press made not a sound
4. Loaded the Pulley system with 2 Kg again at the 12 times MA point = 2X3X12 = 72 Kg - Cheddar heaven right there.
5. Delusions of grandeur here but loaded with 5KG and the 12 times point 5X3X12 = 180 KG !!!  Cantal here we come ! the arm is now nearly at 90 Degrees but not a sound no deformation of the shoulder joins (though only held it there for 10 minutes).  A longer exposure at this force and the press might experience some deformation.
6. Crushed sanding block.

The throw on the pulley at 3 time is quite long so may be no need to get too high and may not even get to use it !!

This weekend will be a very august Cheese indeed.

-- Mal
 

[awakephd]

Nicely done! AC4U. Now to put the new press to work on some cheese ...

[Stinky]

I think I'm going to make this sometime. Perhaps not exactly the same, more like Andy's...

But it looks beautiful.

[OzzieCheese]

Yeah ! Andy's is quite balanced work of art and design - mine more like a Mack truck - Rugged practicality.

The wooden design is great and easily modified for the available wood.  There are two crucial measurement I found
1. The width and height of the cross member - Mine is higher and slightly wider than the plan to fit my pot when pressing under whey
2. the other is Dimensions of the ram and it's housing to stop the cheese being pushed one or the other. But, don't fret as it will move slightly and easily controlled.  I have glued and calibrated a small spirit level on the ram to make sure it is going down square.
If you make the frame of the press as sturdy and tight - use plenty of Dowels and strong glue (I used Gorilla glue, don't use PVA, it's not strong enough), you will remove the torsion twisting moment caused by the two arms.

A Cheddar this weekend - with full coverage of the pressing.
   
-- Mal

[shaneb]

It looks great Mal. Well done. Have a cheese from me also. I'm looking forward to seeing your cheddar make.

Shane