Custom Vacuum Table 'Hold Down' System - piping/valve advice
	
	
		Hi,
We are looking at getting a CNC (8' x 4') router, we are going to be cutting 9mm birch panels.
I am just designing a Vacuum Table system to allow us to have 6+ vacuum sections on the bed, i found a great tutorial from a US source.
The question i have .. if using 50mm piping to create the vac distribution system under the table with cut off valves for each section. What grade of piping and valves should i be looking at? 
Many Thanks!
James
	 
	
	
	
		Re: Custom Vacuum Table 'Hold Down' System - piping/valve advice
	
	
		No personal experience but a place I visited some time ago used solvent welded waste water pipe. Sorry but I never noticed the valves.
	 
	
	
	
		Re: Custom Vacuum Table 'Hold Down' System - piping/valve advice
	
	
		I would have thought any grade of piping would do, so long as it is rigid. If you produce a perfect vacuum you will have an external pressure on the pipework of 1 bar. This is minimal compared to the internal pressure that most pipes take. Class C pcv pipe will take an internal pressure of 9 bar for example.
	 
	
	
	
		Re: Custom Vacuum Table 'Hold Down' System - piping/valve advice
	
	
		
	Quote:
	
		
		
			
				Originally Posted by 
pavlo
				
			 
			I would have thought any grade of piping would do, so long as it is rigid. If you produce a perfect vacuum you will have an external pressure on the pipework of 1 bar. This is minimal compared to the internal pressure that most pipes take. Class C pcv pipe will take an internal pressure of 9 bar for example.
			
		
	 
 The pressure for a vacuum though is in the opposite direction to which the fittings are designed for. Perhaps could make a difference... but I'm only guessing!
	 
	
	
	
		Re: Custom Vacuum Table 'Hold Down' System - piping/valve advice
	
	
		
	Quote:
	
		
		
			
				Originally Posted by 
Jonathan
				
			 
			The pressure for a vacuum though is in the opposite direction to which the fittings are designed for. Perhaps could make a difference... but I'm only guessing!
			
		
	 
 Should not be a problem if using solvent welded pipe.
Bruce