Sciencemadness Discussion Board - Need an adaptor for new vacuum pump

Need an adaptor for new vacuum pump

draculic acid69 - 14-9-2020 at 23:24

Ok so I bought a new vacuum pump from eBay and without spending more on the gas manifold hoses I can't figure out how to attach a regular vac hose or a hose barb or any normal brass connection to it.nowhere on the box or instructions or on any part of the product description does it say more than 1/4" sae connection.now I've been everywhere I can think of and asked everywhere and googled the shit out of what I'm looking for and apart from one place in America (that can deliver between Oct and Nov) I've gotten nowhere.there is no fitting that attaches to a male sae fitting that goes to anything else that will connect a vacuum hose or a barb connection without using a 6mm sae to flarenut that would require buying a flaring tool and some 6mm copper pipe or buying special brazing solder that will connect steel to brass. Short of unscrewing the glued in brass fitting and hoping it'll fit a standard brass connection of some sort I'm lost here.this is the pump I'm talking about :https://www.ebay.com.au/p/11026934504?iid=252779100091

If anyone has any recommendations I'd be glad to hear them

[Edited on 15-9-2020 by draculic acid69]

Fery - 15-9-2020 at 02:42

I attach rubber vacuum hose directly to the brass end under the small blue cap no matter there is a screw on its surface... mine pump has 2 openings with different diameters, I can use only one or both simultaneously e.g. one for evacuating distillation apparatus and the second one to attach a manometer.
You probably know, but better to repeat again - before turning the pump on, never forget to open (unscrew) the big blue cap, so the air/gas can freely leave the pump without blasting the cap off the pump into you face/eyes/etc.

Lion850 - 15-9-2020 at 03:20

I got got a nut and ferrule crimped to a short piece of stainless tube by a local hydraulics company. Clear thick wall plastic hose from Bunnings fits snugly over the tube. Vacuum as we use it is only 1 bar pressure difference at most so small bore plastic hose easily withstands it without flattening.

monolithic - 15-9-2020 at 03:22

Try removing the fitting from the pump housing. I'm guessing it's just a regular NPT thread with some thread sealant, doesn't look like there's an o-ring or anything fancy. If that's the case and it's not some proprietary size, just buy an NPT to hose barb adapter.

Herr Haber - 15-9-2020 at 04:40

Quote: Originally posted by Fery

You probably know, but better to repeat again - before turning the pump on, never forget to open (unscrew) the big blue cap, so the air/gas can freely leave the pump without blasting the cap off the pump into you face/eyes/etc.

I'm not sure I got this right but if you get the cap in your face that probably means you dont attach another tube to the exit of your pump ?
If that's so, you're spraying right into the air micro droplets of whatever you are distilling and that, obviously is not good for you or for your stuff.

wg48temp9 - 15-9-2020 at 10:23

You could use a hot melt gun to attach a hose or better yet to attach a copper plumbing reducing coupling.

copper-coupling.jpg - 3kB

You can cascade different couplings to get to a variety of diameters.

You should check you local plumbing store they will have variuous parts you may be able to use see https://www.google.com/search?q=copper+rescind+coupling+plum...

[Edited on 9/15/2020 by wg48temp9]

draculic acid69 - 15-9-2020 at 14:59

Quote: Originally posted by Fery

I attach rubber vacuum hose directly to the brass end under the small blue cap no matter there is a screw on its surface... mine pump has 2 openings with different diameters, I can use only one or both simultaneously e.g. one for evacuating distillation apparatus and the second one to attach a manometer.
You probably know, but better to repeat again - before turning the pump on, never forget to open (unscrew) the big blue cap, so the air/gas can freely leave the pump without blasting the cap off the pump into you face/eyes/etc.

I would have thought that attaching the hose directly would not be leak proof especially at high vacuum.but if it works I'll try that first.

draculic acid69 - 15-9-2020 at 15:05

Quote: Originally posted by Lion850

I got got a nut and ferrule crimped to a short piece of stainless tube by a local hydraulics company. Clear thick wall plastic hose from Bunnings fits snugly over the tube. Vacuum as we use it is only 1 bar pressure difference at most so small bore plastic hose easily withstands it without flattening.

That's sort of what I tried to accomplish yesterday but bcoz I didn't have the pump with me ppl weren't getting what I was trying to ask for (it's an uncommon request)
Even when I laid it out for them they still didn't get it. I did get a nut that attached to the pump but it needs a copper or ss 6mm pipe that needs to be flared(don't want to spend$50 on a flare tool just for this and in the end I gave up and just planned to have a plumber do it for me but that requires finding a plumber..

draculic acid69 - 15-9-2020 at 15:07

Quote: Originally posted by monolithic

Try removing the fitting from the pump housing. I'm guessing it's just a regular NPT thread with some thread sealant, doesn't look like there's an o-ring or anything fancy. If that's the case and it's not some proprietary size, just buy an NPT to hose barb adapter.

This is a last resort.i don't want to risk it until there's no other possibilities

draculic acid69 - 15-9-2020 at 15:10

Quote: Originally posted by Fery

So does that mean that the blue cap has to stay off? I thought it was a oil mist filter thing.mine has a cloth filter and holes in it to let vapours out.i was thinking of putting a large aquarium tube to outside from it.

Lion850 - 15-9-2020 at 16:14

The hydraulic shop here in Redcliffe charged me 10 bucks for 2 of these pieces

9E62FFB4-832E-460D-9835-BCE929EFB5CA.jpeg - 71kB

7E6D0F41-9BDE-42D9-8EFB-3140B6D011B9.jpeg - 90kB

draculic acid69 - 15-9-2020 at 18:36

Quote: Originally posted by Lion850

The hydraulic shop here in Redcliffe charged me 10 bucks for 2 of these pieces

I asked the people at each place I went to come up with something similar to this after I'd asked about adequate connectors and no one could grasp the concept of what I was trying to accomplish.if I had the pump with me they might have understood but without it they were lost.didnt matter how I explained it with pictures, & drawings I came home with a single nut which is next to useless on its own.very frustrating day.

16002235526266160546390188955.jpg - 480kB

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Lion850 - 15-9-2020 at 20:57

Take the pump with, as you say, and show them my photos. If available get the nut in stainless; I got two normal plated nuts, one is rusting and the other not which is strange.

draculic acid69 - 16-9-2020 at 18:40

Don't have a car at the moment so taking it with me is.a no-go.if I find a fridge/AC or plumbing supply and get some 6mm copper or preferably as pipe they will probably have a flare tool and be able to attach the nut to it for me.anyways I tried putting the hose directly on the same fitting and it works fine for vac filtration but i don't know about doing a vac distillation with it that way,I'll figure something out.

draculic acid69 - 17-9-2020 at 07:00

This pump gets really hot real quick it was too hot to touch and it was smoking after being on for like ten minutes is this normal?

[Edited on 17-9-2020 by draculic acid69]

CouchHatter - 17-9-2020 at 21:20

I have a spray/suck back trap for my aspirator. For hose barbs I simply drilled a hole through two bolts and stuck some PVC tubing over the threads. PTFE pipe compound is great to fill the space between tubing and threads. Concentric PVC tubes also make good reducers to column barbs, vacuum takeoff etc. Will hold about 150 mmHg, which is aboit as far as my aspirator will go with tepid water.
That does not sound like your pump is working properly. I hate to ask but if you didn't replace the oil it might be gone, low, or dirty. Does it have oil? Smoking sounds very bad. I'd find a manual and look for a troubleshooting section before turning it on again.

draculic acid69 - 18-9-2020 at 01:57

Quote: Originally posted by CouchHatter

I have a spray/suck back trap for my aspirator. For hose barbs I simply drilled a hole through two bolts and stuck some PVC tubing over the threads. PTFE pipe compound is great to fill the space between tubing and threads. Concentric PVC tubes also make good reducers to column barbs, vacuum takeoff etc. Will hold about 150 mmHg, which is aboit as far as my aspirator will go with tepid water.
That does not sound like your pump is working properly. I hate to ask but if you didn't replace the oil it might be gone, low, or dirty. Does it have oil? Smoking sounds very bad. I'd find a manual and look for a troubleshooting section before turning it on again.

The manual has next to no information at all about anything.other ppl who have bought them also say that the manual gives no help at all.it came empty with a bottle of oil which went a bit murky at first use (vac filtration of a water solution) but has cleared up maybe the smoke was oil vapour or water vapour it was hard to tell but it got really hot first time enough that I turned it off. The next few times it didn't get that hot but I'm a bit worried about it being faulty.

draculic acid69 - 18-9-2020 at 02:02

On the good side of things I found an adequate fitting for half the price of the one I found on eBay and I got it today not 6weeks from now. Can attach a hose directly to the pump barb now.

draculic acid69 - 18-9-2020 at 02:41

Think I might also attach a fitting to the output so I can lead fumes outside or wherever.sitting next to this thing is a no-go when it's running.it spits oil out everywhere and anything near it gets a coating of oil including any ones lungs who is also in the same room.im gunna run this in it's own cardboard box with an exhaust hose leading outside.