Hi , I worked for Edwards High Vacuum for 26 Years . At the Shoreham site , and also travelled abroad teaching other Engineers how to build and service these and a great many other of the Edwards range of Pumps . (: . Good luck with that little 0.7 .
Rebuilding a nightmarishly varnished 0.7 pump picked up at an online auction. I have a question about the vanes. I assume when they rotate, either centrifugal force or possibly vaccum pulls them out into position, is that correct? I've seen other, really cheap pumps fitted with springs between the two pieces, but saw nothing like that in the 0.7 pump. Just making sure i didn't miss anything in the rebuild. Thanks to anyone who knows what I'm talking about and can answer.
There were no springs between the vanes. There is a spring radially down the center of the pump that presses the bits together along the central shaft (I believe part #67 in the diagram, listed as shaft spring), but otherwise nothing to press the vanes outwards. The rebuild kit diagram also doesn't seem to show any. Search for "Edwards A371-71-840 Issue F" for the rebuild kit PDF I'm looking at, which is different from the one I used in the video. Good luck!
Thanks Martin; this was wicked helpful! I have very little mechanical experience and don't know what a lot of these parts are supposed to do, which makes diagnostics a bit tricky. How well is the oil pump flapper supposed to align with the hole in the secondary body (you reattach it off-camera at 11:59)?
Sorry for the lack of reply - let me review my footage, I cut a bunch out. Probably aligned about as best you can, but I don't think it's super critical to get it to the micron.
Hello Martin, Can you help me with element called Gas Ballast Valve - small H shaped spacer like thing? The GBV (number 64 on diagram) went missing after i dynamicly rised the "plug" (nr 43). I also make stupid things and now i need to make myself a new one. Could you describe what kind of material it was made of (PTFE?) and measure its thickness maybe?
Hi @sitgard, I don't recall the part clearly enough to recall what kind of material it was made out of or how thick. Unfortunately I would have to disassemble the entire pump I think to get access to that part (or disassemble it well past where I would like to at this point), sorry...
Thanks for your replay! I was hoping that you keep old parts somewhere. I've managed somehow! Based on the e2m5 docs i've discovered that this one way valve plate is made with PTFE. and with some rough measurements it seems that thickness must be below 2mm in order for it to work.@@MartinDoesStupidThings
@@sitgard No, I tossed all the old parts once I verified everything was working and I could verify it was pulling a good vacuum. Glad you got it worked out though! I've occasionally been trolling ebay for a 2.5 -5 sized pump to put in my scanning electron microscope, I won a bid on one at one point but they cancelled the order after the pump 'started leaking oil' because they were too lazy to drain it... XD Ohwell.
Probably the only video I could find on these pumps. Thank you!
Hi , I worked for Edwards High Vacuum for 26 Years . At the Shoreham site , and also travelled abroad teaching other Engineers how to build and service these and a great many other of the Edwards range of Pumps . (: . Good luck with that little 0.7 .
nicely done ! you've added to the body of "I wonder if youtube has a video on that...." collection!
This is awesome! 👏
Very interesting video! Thank you for sharing!
Rebuilding a nightmarishly varnished 0.7 pump picked up at an online auction. I have a question about the vanes. I assume when they rotate, either centrifugal force or possibly vaccum pulls them out into position, is that correct? I've seen other, really cheap pumps fitted with springs between the two pieces, but saw nothing like that in the 0.7 pump. Just making sure i didn't miss anything in the rebuild. Thanks to anyone who knows what I'm talking about and can answer.
There were no springs between the vanes. There is a spring radially down the center of the pump that presses the bits together along the central shaft (I believe part #67 in the diagram, listed as shaft spring), but otherwise nothing to press the vanes outwards. The rebuild kit diagram also doesn't seem to show any. Search for "Edwards A371-71-840 Issue F" for the rebuild kit PDF I'm looking at, which is different from the one I used in the video. Good luck!
Thanks Martin; this was wicked helpful! I have very little mechanical experience and don't know what a lot of these parts are supposed to do, which makes diagnostics a bit tricky. How well is the oil pump flapper supposed to align with the hole in the secondary body (you reattach it off-camera at 11:59)?
Sorry for the lack of reply - let me review my footage, I cut a bunch out. Probably aligned about as best you can, but I don't think it's super critical to get it to the micron.
Hello Martin, Can you help me with element called Gas Ballast Valve - small H shaped spacer like thing? The GBV (number 64 on diagram) went missing after i dynamicly rised the "plug" (nr 43). I also make stupid things and now i need to make myself a new one. Could you describe what kind of material it was made of (PTFE?) and measure its thickness maybe?
Hi @sitgard, I don't recall the part clearly enough to recall what kind of material it was made out of or how thick. Unfortunately I would have to disassemble the entire pump I think to get access to that part (or disassemble it well past where I would like to at this point), sorry...
Thanks for your replay! I was hoping that you keep old parts somewhere. I've managed somehow! Based on the e2m5 docs i've discovered that this one way valve plate is made with PTFE. and with some rough measurements it seems that thickness must be below 2mm in order for it to work.@@MartinDoesStupidThings
@@sitgard No, I tossed all the old parts once I verified everything was working and I could verify it was pulling a good vacuum. Glad you got it worked out though! I've occasionally been trolling ebay for a 2.5 -5 sized pump to put in my scanning electron microscope, I won a bid on one at one point but they cancelled the order after the pump 'started leaking oil' because they were too lazy to drain it... XD Ohwell.