Cleaning/Repairing Edwards E2M5

Every fusor and fusion system seems to need a vacuum. This area is for detailed discussion of vacuum systems, materials, gauging, etc. related to fusor or fusion research.
Chris Mullins
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Re: Cleaning/Repairing Edwards E2M5

Post by Chris Mullins »

A gauge that's been used by several here (I have two) is the MKS 901p, good from atmosphere down to 1E-5 Torr, with log analog output and serial interface. Here are a couple of discussions about it:

General discussion: viewtopic.php?f=10&t=11533

RS-232 interface board: viewtopic.php?f=10&t=11730

You can usually find them (used) on ebay for around $35-$45 with KF16 flange.
Bruce Meagher
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Re: Cleaning/Repairing Edwards E2M5

Post by Bruce Meagher »

Ameen Aydan wrote: Thu Jan 03, 2019 6:50 pm ... I still need to find a proper inlet valve for gauging. I can't find anything so far for a good price. I need it to be a KF flange which is the biggest problem. Any recommendations?
You could try <https://www.ebay.com/itm/292158415411> for $12.50 shipped. The image below is what I received. It doesn't have the proper lip for an o-ring seal, but those on a budget can make it work. How to get a proper seal with these large BSP threads without an o-ring is an exercise left to the reader.

Bruce
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Dennis P Brown
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Re: Cleaning/Repairing Edwards E2M5

Post by Dennis P Brown »

On a mechanical pump, teflon tape will seal it very well. I've had success even with 10^-5 torr in my chamber but I don't recommend it generally for those high vac applications.
Ameen Aydan
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Re: Cleaning/Repairing Edwards E2M5

Post by Ameen Aydan »

Hello

Thank you all so much for your suggestions, I can't say enough thanks in a life time. I just took a look and will purchase it soon. Since I'm from Canada, the price of shipping is $16 dollars... So as soon as I get that all worked out I should be able to purchase it. I also purchased an MKS 901P. The seller says the product is already calibrated and works perfectly! I purchased it long before the previous update, just forgot to mention it. Oh, and It was sold to me for $35 but the shipping was (as to be expected) $15. I hate it but I have to live with it... Oh well. An update on my pump will be coming soon. I just have to finish some useless homework first.

Ameen Aydan
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Re: Cleaning/Repairing Edwards E2M5

Post by Ameen Aydan »

Hi all,

I finally programmed my MKS 901P using python and got it reading pressures and stuff. I will detail the whole procedure later. I also finally got the necessary adaptors and clamps for testing so I got right to it.

Because the pics are really big in size i kept them in a separate google drive file. It's better to open them in a separate tab as I will be referring to them based on the number of the pic. I will use this system now and on. Here is the link to my results --> https://drive.google.com/drive/folders/ ... _cKYdHM7dh

So first I took out a little of the disgusting oil the was already in the pump (1). It was a viscous mess and I don't even know how beat this pump was.

Next, I put in about 3 quarters of FF into the pump and ran it for 6 hours total. Following that I decanted the oil and it was off colour but still had the original red colour. This clearly meant that something was being cleaning out! By now I hadn't gotten my gauge so I I couldn't do anything. 2 is the pic of the decanted oil.

Now, I added the little bit of FF I had so that the oil line was slightly above minimum. I was distracted with school and exams and the whole mess made me forget about it for month. I came back to it yesterday and I let the pump run for about 2 hours to let the oil warm up. The oil I decanted in pic 3 was very concerning. This was because of how dirty it was! I didn't expect it to look anything like that and so it was a complete surprise. This clearly meant that even though I used FF I should have left it for a bit longer! It also goes to show how frigin' dirty it is, and how much might be left.

So after that I out about a quarter of my normal vacuum oil into the pump, again, just above the minimum line, and let the run for 2 hours. It came out slightly less dirty than the FF I mentioned. Again, very concerning. Now I would also like to mention that even though I used a little bit of the oil, when I connected the gauge and I gave a good pump down, I reached 13 micron in about 3 minutes. It's not good but not bad either. So I tried doing it again, and again, and again. Every single time after that I only managed to get 10 Torr. I will put a video up soon, it'll be named 4.

OK so, I was pretty annoyed. So I just decanted the oil and added the rest of my bottle until there was enough oil that it was slightly bellow the max on the oil metre. I gave the same pump down and had everything connected properly. Again, I only achieved 10 Torr.

I'm still here and I don't know what to do. Here are my assumptions. I'm using the recommended teflon the Dennis told me about. I think that there is probably some really big leaking going on. I want to get the proper inlet but its too expensive. I might try welding a lip so I can get the proper o-ring seal. The second thing that I think is wrong is the gauge. When set to factory default the gauge reads 769 Torr at normal pressure. When I pumped it down and got to 13 microns, it displayed 740 Torr at normal pressure. So I set it back to factory default and got the 760 Torr again.

I put the gauge strait on the inlet so I think that when I pump down some of the pump oil got on the gauge and damaged the sensor. I wouldn't know if that's true because i'm not getting any red lights (indicate that the sensor is faulty). I know that when I swiped the inner part of the gauge it felt a bit oily, but I could never see any actual oil. Maybe it was just a placebo?!?

Anyways I have a lot more to show but I will leave it out for later. For now I just want to know if my pump is just garbage. I spent too much time and money on this so it would be disappointing to just throw it out. Is there anything wrong with my gauge? I don't know what steps to take at this point.

Ameen Aydan
Last edited by Ameen Aydan on Thu Feb 14, 2019 11:04 am, edited 1 time in total.
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Dennis P Brown
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Re: Cleaning/Repairing Edwards E2M5

Post by Dennis P Brown »

Sorry the pump is still making your oil so dirty. By the way, I can only see one pic when I open the link you included - a pic of your tools and teflon tape. Is there only that pic?

You cleaned the inside case but did you dis-assemble the actual pump stages? I did this with my pump and cleaned it. That made a huge difference. Consider the amount of dirt/corrosion in your case, the inside of the pump chamber is likely bad, too. Hopefully, none of the critical surfaces are damaged. That those areas are contaminated might explain your failure o get down to a few microns. Your pump oil should stay clean when running the pump so likely the internal mechanism does need cleaning as well.
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Re: Cleaning/Repairing Edwards E2M5

Post by Ameen Aydan »

Hello,

Thanks for your reply. I only cleaning the case and not the stages. Richard advised me not to do so until I tested the pump. I don't want to spend more money so i'm afraid of opening up the stages as that would require me to change the o-rings. I remember someone saying that the orings can only be used once...

I can do it but I think a confirmation would be better. I would also like to be 100% sure the gauge is not damaged. Do you think I should go ahead?
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Dennis P Brown
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Re: Cleaning/Repairing Edwards E2M5

Post by Dennis P Brown »

Gauges can always mislead. So, confirming that it is accurate is very important.

As for my pump, the dis-assembly of the actual internal vacuum pump assembly was done without a kit. I did damage a flat gasket but silicon sealant fixed that. I reused the o-rings but that could be hit or miss - one did look really flat but I simply reused it (again, a little silicon sealant.) The pump works fine and gets me down to under 2 microns (guess I got lucky.)

I really did need to do it since I found issues with some internal parts that did need serious cleaning - springs, balls and some linking sections.

Doing this type of rebuild is a judgement call. I'd suggest first checking the gauge, of course.

Still, your oil is coming out dirty simply by normal operation and that is certainly an issue and will have to be addressed in all likelihood (and is costly to keep replacing.) Getting a rebuild kit might be worth the cost but as you said, you've put enough money into it.

Then it comes down to deciding how much another pump would cost. If the pump can't get down to a few microns (via a properly working gauge), then frankly, at that point, you have nothing to lose and a further break down would appear worthwhile. Failure and maybe just get rid of the pump. Success and you have the pump and at an acceptable cost. Of course, you could still buy a rebuild kit if you decide to keep it after discovering the o-rings are a once use only. Your call.

If you do decide to dis-assemble the vacuum stages (at some point), remember to take photo's to reference for re-assembly and keep the order correct for all stages during cleaning. They need to be re-assembled as they were originally.
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Re: Cleaning/Repairing Edwards E2M5

Post by Ameen Aydan »

Hello,

I think I will just go ahead with that route. I have seen people do it on these forums in the past so why not give it a go. If it doesn't go well and this thing is a peice of trash, then at least I know that I got my money back on it. I told the seller about the condition this pump and he refunded me all the money. I only spent money on the oil and gasket. About $100 as of now.

As for the gauge, the seller told me it was calibrated and in working condition. If that's the case then my pump is infact shitty. Maybe it's the Teflon seal? I dunno.

I will go ahead and disassemble the pump. Because i just put in the new oil yesterday I will just reuse it and filter it.

Do you know by any chance how long it took you? Do you think I can reuse the oil if it's that new, and unused? And last but not least, what is that silicon thing you were talking about? You don't have to answer the questions.

I fixed the Google drive link

I'll send an update soon.

Ameen Aydan
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Re: Cleaning/Repairing Edwards E2M5

Post by Bruce Meagher »

Before you disassemble your pump are your sure you don't have a leak around the BSP threads on the intake flange? I know I steered you to the inexpensive intake flange, and as I mentioned this cheap version does not have a proper o-ring seal. The BSP threads are straight making it a little more difficult to seal. Are you just using a few wraps of teflon tape? You could try adding vacuum sealing tape, melt some beeswax around the fitting interface, use liquid teflon, or even try a few drops of vacuum oil at the interface to see if you have a leak here.

edit: I didn't read your post closely enough. I see you reached 13 mtorr previously, but now are only getting to 10 Torr. Something doesn't make sense. I think you have either created a leak between runs or your gauge is fouled.

Bruce
Last edited by Bruce Meagher on Thu Feb 14, 2019 7:59 pm, edited 2 times in total.
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Richard Hull
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Re: Cleaning/Repairing Edwards E2M5

Post by Richard Hull »

10 or even 15 microns is about the best one can ever hope for on a used pump. and will perform flawlessly using a diff pump or turbo. Short of a rebuild I would not expect much better. You have done the best that might be expected for a used pump. From my point of view, you are good to go for use in a real fusor. Even with the oil as is, you have a fine pump.

Richard Hull
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Re: Cleaning/Repairing Edwards E2M5

Post by Ameen Aydan »

Hello,

Bruce Meagher gave me his gauge to use and test and it’s giving the exact same results. 25 torr and that’s the max. My gauge reads 35 torr so I do need to calibrate slightly. Does anyone know if it is bad if I don''t calibrate? This clearly shows that there is nothing wrong with my gauge.

He did give me an intake flange but it was too big. Does anyone have one the are willing to lend me for a month or two?
These results are still using the Teflon seal. Because I got 13 micron last try then it seems that my problem is the inlet not being secure enough. I doubt that my pump would be doing something wrong if I previously got anything a good result...

An inlet should do the job

Ameen Aydan
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Re: Cleaning/Repairing Edwards E2M5

Post by John Futter »

Get rid of the teflon tape
use loctite 569 Hydrulic sealant (thickliquid) or Loctite 290 (superwickin)
Teflon tape is for plumbing of water systems not high vacuum
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Re: Cleaning/Repairing Edwards E2M5

Post by Ameen Aydan »

Would JB weld do the same?
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Re: Cleaning/Repairing Edwards E2M5

Post by Rex Allers »

Can you give us a pic of what you plan to connect to what?

I love JB Weld for connecting things that have vacuum down to 1 micron or a bit less. But where I have used it is to permanently connect pieces. It is not wise for something threaded you may ever want to unscrew.

Last discussed, I think it was sealing threads. Not a job for JB Weld unless you never want the option to undo it.

Assuming you are still trying to evaluate your pump's capability, give us that pic of how you will connect pump to your gauge.
Rex Allers
Ameen Aydan
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Re: Cleaning/Repairing Edwards E2M5

Post by Ameen Aydan »

Sorry it's been such a long time but I'm finally back to it!

So I decided that the pump I got was most likely just defective. Though I managed to reach 13 micron at one point, I don't think that's going to happen again....

I would want to repair it but I don't have the patience or time to do such a thing. I would need to get oil and a whole bunch of parts that I'm simply not prepared to spend my time on finding.

Below I have attached pictures of the fitting. I connect my gauge directly to the adapter. That way I get an accurate read out.

I choose to purchase a new pump to see if I get any luck. My new pump seems to have the same issue. On the inside, the seller says that its in perfect condition but the outside is just pretty dirty. In the picture you can see the readout of what I got on the new pump. The best I managed to get was about 90 microns though.

At this point I give up. I have two broken pumps that have put a sizable hole in my pocket so I'm just going to resell them and see what I can get.

Should I just JB weld the adapter to my new pump and see what the reading gives me? I don't imagine doing so will affect the pumps performance. And at this point the pump is done for so this little adjustment wont make a difference in my eyes.

Link to the pictures: https://drive.google.com/drive/folders/ ... sp=sharing

Ameen Aydan
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Rich Feldman
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Re: Cleaning/Repairing Edwards E2M5

Post by Rich Feldman »

Go back and read what Richard Hull said.

Why are you saying 25 micron ultimate pressure means the first pump is no good?
Suppose you could get below 10 microns with a brand new pump, and some luck.
Would that make a difference in your fusor project?
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Ameen Aydan
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Re: Cleaning/Repairing Edwards E2M5

Post by Ameen Aydan »

Hello,

Just updating everyone who might read this thread. I finally just traded the two pumps for an Alcatel 2002. It works perfectly fine, reaches 5 microns on the gauge and has very minimal noise. I got those two pump together for $350 cad so I basically paid $350 for the Alcatel. On the high side for the pump I got but at least I have all my fusor components and I can begin construction.

Will update with photos soon

Thanks for the help all,
AA
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Re: Cleaning/Repairing Edwards E2M5

Post by Alex Kahn »

Hi all!
I came here because I also own an E2M5 vacuum pump and found this nice informative thread.
Same model that I have and in need for maintenance.

I found my pump some years ago for 50€ and never really used it since.
The purpose was to repair water damaged PCB or electronic devices and laminating resins under vacuum. Always good to have vacuum capability in your workshop I thought…

The problem is that my pump show heavy corrosion. The oil is very brown whenever I change the oil. A rusted crust is visible through the glass and when I look into the oil cap opening I get nightmares.

However the pump runs and after some hours of runtime it achieved 30 microns peak vacuum.
It started around 200 microns with new oil and slowly got better.
The project of the week is to install a split climate system to my garage. To put it into operation the proper way I need good vacuum of course.
As a gauge I use a digital TESTO 552 device. Cheap and not as scientific as the equipment from the lab but in my view sufficient for 10-3 Torr vacuum area.

Before I filled new oil into the pump unfortunately I did a mistake I think.
I filled the oil compartement with a cleaning solution that is somehow partly alcoholic or at least hydrophile. I thought it was mineral based cleaning solution but it was not.

I turned the pump on in the morning and after 3 rotations it seized and stopped turning.
Oh Oh not good.

What do you guys think I should do?
Detach Motor and try manually and maybe backwards?
Or time for disassembly now?


B1D22D09-E663-4842-ACDE-1ED963C395F5.jpeg
F496CCD3-B5A5-481E-851B-59224D2A6E9F.jpeg
B26C1D6F-26AA-42BF-B9A4-874F91FDBFF8.jpeg
4EB11795-5ED7-402A-A80F-3863A67F4BE9.jpeg
Ameen Aydan
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Re: Cleaning/Repairing Edwards E2M5

Post by Ameen Aydan »

I know this is a late reply, but at this point, you have nothing to lose with opening up the pump and completely disassembling it. IMO, a cleaning oil for these kinds of issues (including mine) is mostly just... hopeless.

Open the pump and disassemble everything, down to the pump vanes. Clean what you can within reason and put some fresh oil in there. I'm not sure if there are any single-use components you'd need to replace after opening everything. Honestly, though, it's nothing a little grease and a prayer can't fix. Please don't bother with an overhaul kit unless you're sure it's worth it.

You can find exploded diagrams for this pump almost anywhere.

Please update if you get the chance!
Oscar Anderson
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Re: Cleaning/Repairing Edwards E2M5

Post by Oscar Anderson »

I'd hold off tearing it down completely. Aligning vane pumps can be something of a headache. Just dismantling and cleaning it is, well, a project, and you probably won't find anything at all.

It would, in general, take quite a lot to make a pump seize in 3 revolutions. Even running without any oil at all.

In general, I don't like putting anything other than vacuum pump oil into a pump. It's really difficult to get everything out of a pump - there's always a little left in there, and if it has a very high vapor pressure, you can kiss your ultimate pressure goodbye.

The inside of your pump looks like just about every rotary vane pump I see at surplus, including both of my Welch pumps. Odds are good that most of the crud is in the oil tank and not inside the pump itself. It's not good, but it's typical. Most of these pumps have hard lives, and a lot of them get little to no maintenance. Over time, with use and oil changes, it will clean up.

Removing the motor is fairly low risk on most pumps, and this will allow you to do two things. First, you can ascertain whether this is a pump issue or a motor issue. Second, it gives you some access to try and turn the pump by hand. You may need to make something that will mate with the shaft coupling to do this, however.

If you really can't get it to turn, then start looking at tearing it down, but again, I have a very hard time that a pump actually seized in 3 revolutions.

Tearing these things down is borderline on being worth it. You can pick up pumps that aren't destroyed for a couple hundred bucks (sometimes a lot less). If you tear it down, you're probably going to need to buy a minor rebuild kit (mostly gaskets and possibly a shaft seal) at a minimum, and you're going to spend the better part of a day (possibly two) doing it.
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