CEB Cylinder

From Open Source Ecology
Revision as of 23:15, 21 November 2018 by Marcin (talk | contribs) (→‎Working Doc)
Jump to navigation Jump to search

Abstract

The OSE CEB press requires a custom cylinder - 5x8x2.5 inch, but with 3.5" of rod sticking out and no rod end.

The 5" cylinders are about $500 - and an open source version can be half of that if we start from honed cylinder tubing. It is useful to open-source that - as that once more turns every cylinder into a reusable module. The main point of open-sourcing by OSE is standardizing to one build method which allows for universal interchangeability of parts and 3D printed seals, such that any cylinder can be reworked or repurposed easily and inexpensively.


Working Doc

edit

Design by Aidan

Here is a version uploaded to the OSE Wiki. It should work but may have design flaws. I'm using an O-ring to seal the cylinder in the cap trepan groove. This is questionable.
File:Universal Cylinder Builder ADW.FCStd


I've been working on a cad file for the Open Source Cylinder. Here is a link to the alpha stage of the file. DROPBOX The end-caps are square with a trepan machined for the tube to seat. The caps could potentially be parted so that a welding operation replaces a machining operation for the tube seat. The Rod is welded to the Piston in my version.

Like the universal tube builder, I'm trying to make it parameterized from a spreadsheet. Here is what the parameters look like right now:

Name	Input (Inches)	Output (mm)	Note
Cap Side Length	4	50.8	
Cap Thickness	1	25.4	
Tube OD	3	38.1	
Tube Wall Thickness	0.25	6.35	
Piston Thickness	1	25.4	
Piston Seal Inner, Height	0.3125	7.9375	
Piston Seal Inner, ID	2.125	26.9875	
Piston Seal Inner, OD	2.5	31.75	
Piston Seal Outer, Height	0.25	6.35	
Piston Seal Outer, ID	2.125	26.9875	
Piston Seal Outer, OD	2.5	31.75	
Stroke	12	304.8	
Rod OD	1.5	19.05	
Rod Stickout	2.5	63.5	
Cap Seal Outer, Height	0.25	6.35	
Cap Seal Outer, OD	2	25.4	
Cap Seal Outer, ID	1.495	18.9865	
Cap Seal Inner, Height	0.25	6.35	
Cap Seal Inner, OD	2	25.4	
Cap Seal Inner, ID	1.495	18.9865	

Need to add a few parameters like tie-rod diameter. I think the model may need to be scrapped. Especially if one looks at the dependency graph lol. I didn't take as intentional an approach to modeling it as I could have.

I believe it is a worthwhile effort, though. A user could generate the CAD for a cylinder of different sizes by simply entering data into a spreadsheet.



Left

Order from East AI Machinery Co, Limited

  • 300 kg of honed tubing
  • Materials for 5 cylinders
  • 3"x4" tubing
  • 1-7/8"x3" tubing
  • 8 mm rod

Cylinder Parts

Rods

Piston

  • 4" Bore 2" Rod Piston

Tubing

Rod Cap

Press Parts

DOM tubing

Sourcing

  • 5x20 - $400 - [3]
  • 5x16 - $366 - [4] -
  • Bore 5"
  • Stroke 16"
  • Rod 2.5"
  • Retracted 27" - if we trim it down, cut off 1.5" - and have 1.5" sticking out as is - we need to add 2" to get 3.5" sticking out. But reduce the length by 8" for 8" stroke. We need to trim the cylinder down by 8" - so contracted length to tip of rod is 19". Extended is 27. If we consider extended with 2" of plate - then the distance from bottom of drawer to the pin mount center is 29"
  • Extended 43"