I got a vacuum pump - Page 1
Forum section: electronics / general

author: GK
author_rank: Super Contributor
timestamp: November 18, 2013, 08:50:35 am
content: Saved this old little unit from the scrap heap a little while ago. The novelty of boiling water at room temperature is starting to wear a bit thin now though, no less due to the fact that just about every dummy I give a demonstration to replies with something along the lines of "it's just sucking the air out of the water, feel the flask, it's not even hot".So what else can I do with it then in the electronics workshop? It's really bloody heavy for its size and makes a good door stop. At a previous place of work one of these was used for the vacuum table of the in-house designed and built ultraviolet PCB exposure box, but that was retarded overkill.

author: amyk
author_rank: Super Contributor
timestamp: November 18, 2013, 08:56:32 am
content: It really sucks, doesn't it?You can try making your own vacuum tubes...

author: andtfoot
author_rank: Unknown
timestamp: November 18, 2013, 09:00:15 am
content: Fibreglassing?Making an industrial strength desoldering gun?

author: apelly
author_rank: Unknown
timestamp: November 18, 2013, 09:05:26 am
content: Quote from: andtfoot on November 18, 2013, 09:00:15 amAwesome silicone molds anyway...

author: deephaven
author_rank: Frequent Contributor
timestamp: November 18, 2013, 09:05:33 am
content: Make Nixie tubes. There is quite a fan base for such things so you could sell quite a few, especially if you made LARGE ones.

author: G7PSK
author_rank: Super Contributor
timestamp: November 18, 2013, 09:09:42 am
content: Vacuum forming of plastic or even thin sheet metal. Get some heat lamps and you could even make your own enclosures.

author: Kjelt
author_rank: Super Contributor
timestamp: November 18, 2013, 09:38:45 am
content: Desoldering station / smd vacuum pincet. As I posted before to someone else:QuoteWorks like a charm and kicks ass of each of these lame $20 vacuumpumps that make a lot of noise when you desolder.

author: GK
author_rank: Super Contributor
timestamp: November 18, 2013, 11:17:19 am
content: Quote from: amyk on November 18, 2013, 08:56:32 amHmm.... need a little more kit than just a vacuum pump though. Quite an impressive amateur video here:Hand Made Vacuum Tubes by Claude Paillard

author: GK
author_rank: Super Contributor
timestamp: November 18, 2013, 11:24:15 am
content: How about an industrial strength penis enlarger?Not that I would need one though. I quite like the idea for the super solder sucker, but only if there is a practical way to have a solder collection reservoir separate from the hand gun. My pet hate with these things is the is little canister (with a stupid internal spring collector in our Hakko at work) that gets clogged up and is a pain to clean out after 5 minutes of desoldering.

author: andtfoot
author_rank: Unknown
timestamp: November 18, 2013, 11:54:52 am
content: Quote from: GK on November 18, 2013, 11:24:15 amMaybe do something like how some dust collectors work?en.wikipedia.org/wiki/Cyclonic_separation

author: GK
author_rank: Super Contributor
timestamp: November 18, 2013, 12:07:48 pm
content: The main hurdle as I see it is with the solder cooling down, solidifying and clogging the vacuum hose to the reservoir.

author: DaveW
author_rank: Frequent Contributor
timestamp: November 18, 2013, 01:19:45 pm
content: Well naturally the first thing is to make marshmallows expand; that novelty lasts a bit longer! They are handy for degassing mixtures when moulding or using potting compound; this means you don't get little bubbles of gas left in the potting which makes it much stronger.You can use it for testing pressure sensors when connected almost directly or whole devices if you put a rough chamber together, I've got a spare one but I think the shipping to Australia might be prohibitive! It's also interesting to see how hot devices get without air to conduct heat away.And you could use it to test a high altitude balloon!

author: george graves
author_rank: Super Contributor
timestamp: November 18, 2013, 01:49:12 pm
content: Quote from: Pippy on November 18, 2013, 12:11:45 pmEeeek! Please don't take anything kipkay does as real. He makes videos just for the money. Half of what he does is faked is some way or the other. (ok 10% of his videos are faked in one way or the other - the rest are link bait.)Quote from: G7PSK on November 18, 2013, 09:09:42 amNot enough flow - the part would cool way before a the part would be sucked down to the mold. You really want a plan old shop vac. Lots of flow.

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 18, 2013, 03:31:01 pm
content: What about DIY freeze drying? You'll also need a very good refrigeration system to do it, but now you have the pump to take the air out of the pipes. Get some old refrigerators and make a cascade with R134a or R152a for the first stage and R410a for the second stage. Should be pretty easy to get it to pull down to -60C or so, maybe even better.

author: G7PSK
author_rank: Super Contributor
timestamp: November 18, 2013, 04:44:09 pm
content: Quote from: george graves on November 18, 2013, 01:49:12 pmIn the mid 70's I used to make steel frames for a company called Lexel Lamb that did vaccum forming of 8X4 foot plastic sheets for street decorations at Christmas, they used quite a small pump a mold made of clay or plaster with lots of holes in it and a big bank of infra red lamps over the work no frame was used to hold the plastic sheet it just flopped over the mold and the final puul dow was done by the vacuum.

author: SeanB
author_rank: Super Contributor
timestamp: November 18, 2013, 06:34:24 pm
content: If you have been boiling water with it you really do need to change the oil as otherwise the water vapour in it will destroy the pump chamber. I change the oil in mine every ferw uses, or when I see it change colour from the regular light straw colour. Oil is very cheap compared to a good pump.

author: Kjelt
author_rank: Super Contributor
timestamp: November 18, 2013, 08:41:29 pm
content: Quote from: SeanB on November 18, 2013, 06:34:24 pmGood post

author: houdini
author_rank: Regular Contributor
timestamp: November 18, 2013, 10:32:17 pm
content: Ben Krasnow has some really cool stuff on youtube using those thing. Every thing from electron microscopes to vapor deposition circuits.

author: notsob
author_rank: Frequent Contributor
timestamp: November 18, 2013, 10:49:03 pm
content: You can also close the vacuum inlet and run it for a while, a lot of the dissolved water will evaporate and migrate out the exhaust due to the vacuum. But yes, the oil is hygroscopic and should be changed regularly.

author: GK
author_rank: Super Contributor
timestamp: November 18, 2013, 10:55:04 pm
content: Quote from: SeanB on November 18, 2013, 06:34:24 pmOK, thanks for the tip. The oil in it stilllooksOK and is yellow in colour, but is decades old now. The pump was sitting unused in storage from at least the '80s.What do you use yours for?

author: GK
author_rank: Super Contributor
timestamp: November 19, 2013, 01:12:33 am
content: BTW, how fiddly are these things on the inside? If I open up the pump housing aiming to give it a wash and cleanout I'm not going to have springs and cogs and other bits and pieces spewing out onto the bench top, am I? Any perishable rubber seals inside?

author: johansen
author_rank: Super Contributor
timestamp: November 19, 2013, 01:20:04 am
content: Biggest thing to watch for is make sure you put the vanes back in the same way they came out. don't mix and match and turn them around. (shouldn't matter that much but if it has thousands of hours on it, then it might)you'll need to make new seals, or buy new. (i've used paper coated in grease)also, don't boil water if you want to pull high vacuums.one thing i've done is make my own vacuum pump oil by pulling a vacuum on a gallon wine jug filled with synthetic motor oil, with a 1500 watt space heater under it, and a shell around it to direct the air flow around the glass. ended up pulling a vacuum on the oil for a few days, at about 70C. when you first turn the pump on you're going to get something equivalent to putting soap in a fountain, so don't fill the jug more than half way.

author: AlfBaz
author_rank: Super Contributor
timestamp: November 19, 2013, 01:27:43 am
content: Do any high voltage transformer stuff?If so you could use it for vacuum varnishing, although it also would also require applying positive pressure after the vacuum stageI just scored what looks like an old dentists pump. Although the intermediate canister (the one that catches the gunk) looks empty from the outside, I'm not game to touch it just yet

author: PedroDaGr8
author_rank: Super Contributor
timestamp: November 19, 2013, 07:27:30 am
content: Here is a teardown I did on an Edwards RV8 vacuum pump. It should give you an idea of what you will encounter.http://www.instructables.com/id/RepairingCleaningUnsiezing-Edwards-RV8-vacuum-pu/As others said, do change the pump oil. It gets old and can gunk up things. Oil tends to be relatively inexpensive so if it's been sitting a while; change it.Sent from my EVO using Tapatalk

author: notsob
author_rank: Frequent Contributor
timestamp: November 19, 2013, 07:35:11 am
content: AND as a reminder to everyone disassembling something - before and as you pull it apart - these new things called smartphones have a camera.So take lots of photos.

author: GK
author_rank: Super Contributor
timestamp: November 19, 2013, 08:04:48 am
content: On second thoughts since the thing works and isn't leaking any oil, I think I'll just keep it closed for now and order some fresh oil for a long overdue change. The prospect of ruining the existing seals pulling it apart and then having to make new ones is really more of a distraction than I need right now. This is a loooooong ago superseded model and I doubt I'd be able to find a factory gasket kit with relative ease. The suggestion of vacuum vanishing/potting HV transformers is one that interests me, as that is something I could have a real need for. I'll have to look into that. However for now the pump is going back into its box and back under the bench.

author: krux
author_rank: Unknown
timestamp: November 19, 2013, 09:00:24 am
content: Quote from: GK on November 18, 2013, 08:50:35 amI know one of my projects I want to make is a Farnsworth demo FusorHere is some info to get you started.http://www.belljar.net/634fusor.pdfAdd a NST, Variac, and a vacuum chamber and you're pretty much there.

author: AlfBaz
author_rank: Super Contributor
timestamp: November 19, 2013, 02:03:18 pm
content: Years ago I worked in a shop that had a vacuum varnishing tank and I remember enjoying its use, namely because of all the valve turning, rattle guns and pneumatics involved.There were two tanks, a square one on the shop floor with two hinged lids on top and a cylindrical one with sphere ends with the top just sitting above floor level. The latter was the vacuum tank and presumably cylindrical/spherical because of the superior strength under pressure/vacuum.These were very large tanks, able to hold very large stators, armatures, wound rotors and transformers.The varnish was kept in the square above ground tank which was often used to dunk stuff into prior to being baked in a large industrial oven, and had a valved pipe going to the bottom of the vacuum tank.You would undo do at least 2 dozen 24mm bolts that held down the spherical lid. It was attached to a swinging boom with a pneumatic ram to lift it.Once the item was inside the vacuum tank, you would measure how high you wanted the varnish to come up so you knew how much to suck out of the square tank. You would then swing the lid into place, line up the hold down lugs, lower the lid and then go around with the rattle gun tightening the bolts.You would then close the air inlet valve to the tank, open up the suction line and turn the pump on.Once the gauge read the right amount of suction you would open the valve on the pipe going from the square tank and simply wait until the varnish level dropped the pre-measured amount. At this stage you would shut off the varnish line.The air inlet line to the vacuum tank would be opened, equalizing pressure and then feed filtered compressed air into the tank. You would leave it pressurised for an amount of time determined by the type of winding. Formed coils (taped copper section) would get a longer stint than normal wire wound coils.When the time was up you would re-open the varnish line and the positive pressure would push the varnish back up into the square tank. When the varnish approached the original level in the square tank, you would close the lids and get ready to close the valve as soon as you heard it bubbling. Needless to say occasionally someone would walk away and if the tank was pretty full inevitably you would end up with varnish bubbling out of the tank.Personally I had never witnessed this but evidence of it was ample by the amount of dried varnish on the surrounding walls

author: robrenz
author_rank: Super Contributor
timestamp: November 19, 2013, 03:22:04 pm
content: You could make yourself one ofthese