DIY Vacuum Fixtures

[Boyan Silyavski]

I will never let at once 6 people in my garage that are reciting "Bend, Bend..."

That was quite impressive collapse on a large scale.

This bellow is my dust separator, made from 200l tank which is 1mm thick. So my 2000w shop vac will not bend it at all when all closed. You can not lift the top either when vac is working, though it just rests there, is not screwed. Pads ring is from old yoga mat. Of course the compressor will pull much more vacuum than the vac cleaner.
By the way this thing works really well. The plastic conical thing is from Aliexpress.




What i did learn these days browsing the web, is that:
-from new to old some compressors worked 4 years non stop in that setup
-in order to work well, the compressor needs to have the pistons checked, the gaskets checked, the reed valves on the head checked and everything cleaned. Air filtered well at the input side. Plus liquid separator , if on a mill.


In fact i started preparing and first checked one compressor, which was in like new state, at least from outside. It was dirty there, the reed valves copper gasket was bad, so i ordered new sheet of copper. The valves were dirty, so wouldn't close well. Luckily the pistons seem new and the piston rings ok at first glance..

This is the biggest one i have/330LPM/, so maybe i will be using it for both purposes. I discovered that all that is needed is to leave the output open. Some people on the net say that even if it is closeed, the air is not building enough to stop the compressor.

[Nthkentman]

Compare the price to this; http://www.trend-uk.com/en/UK/produc...make_kit_.html

I bought one of these...Yet to get enough round tuits to actually make it tho... Wish they'd sent a CNC template idea and not the paper hand router templates :-(

[Boyan Silyavski]

I made some test jig from wood. Works perfectly.

One thing is clear to me now. All hosing from compressor up to the CNC must be industrial 1/4 or 3/8, cause i will step on it, solder over it and so on. It must be strong so no cheap PVC hoses here. Added bonus is that i use the same hoses and extensions like for air. So the only thing i bought is the 3/8 quick connector which i fitted at the compressor inlet side.


Decided to save on connectors :-) so i drilled the vacuum fixture and just pushed the PVC hose inside, it works perfectly. Recessed all the necessary areas 3mm. Drilled hole to the back so the vacuum fixture is self fixing to the table. Hole could be closed and instead fixture clamped.

The mat is non slip mat from chinese shop -2euro. 15mm wide rings, i wanted a superb friction.

Next step will be when i have time to fit the Vacuum switch to the compressor, check the negative pressure achieved and test if using vacuum reservoir/the compressor tank/ is better in any way.

Video : https://plus.google.com/111571569713...ts/BHSTDvFBjks

[Boyan Silyavski]

Just measured the compressor suction- 94Kpa = 705 mmHg = 27.7 inHg= 0.927 Atmospheres , not bad for an old sucker

Now i still have the problem about the compressor switching off after 15-20 min of run, without obvious heating. Any ideas? I am going to use the bigger compressor when repaired the gasket, but i want already to use my fixtures . I read on forums people use 8h non stop the compressor without problems for years, why then this old sucker stops?


By the way i have 2 more micro digital vacuum switches, i bought a lot, used , perfect condition, made in japan, very small size, so PM if interested. 25euro each

[Blackrat]

has the wood been sealed ?

[Boyan Silyavski]

has the wood been sealed ?

No, but it seems is not necessary. Its very dense. I made it from wood as a test to understand better how it works, before making some stuff in aluminum. It seems though it will perfectly work if wooden. it made from a solid kitchen cutting board. however sealing it is recommendable, due to humidity so it would not twist when dry or humid

it will suck probably more air from the actual part, which is has 3mm bottom /pine/

[andy_con]

very useful thread thanks.

a few questions

i know nothing about compressors, can you provide any details incuding photos of how to connect up for sucking/to create vacuum?

a compressor turns on for 5 mins till its full then stops, how do you keep it ogint for an hour without stopping? release air whilst is drawing air in?

[mekanik]

Hi andy
A compressor is controlled by a pressure switch,Tank empty switch it on and compressor will run filling the tank, when it's upto the set pressure the pressure switch kills the supply to the motor, as you use air the tank pressure drops below the switches set point,the contacts close and power is supplied to the motor increasing the pressure.
If using as a vac pump all you need to do is open the outlet valve on your tank so the switch will never see the cutout pressure.
There is usually a filter of some sort on the inlet, use this connection for pulling a vacuum.
Regards
Mike

[andy_con]

I see so leave the drain valve open or something

[Boyan Silyavski]

Time for update.

Bought from ebay an Alcatel 2010 vacuum pump from Lithuania. WOW what a sucker! 7cfpm , 2 stage, 350W. So these days i have been finishing my new Vacuum Pump Station.




Basically the pump is mounted on old air compressor tank, driven by VFD as its motor is 3 phase 350w. The pump is fitted an original exhaust and DIY inlet filter and separator. The pump sucks -filter-hose-tank-quick connector. There is an vacuum sensor switch fitted to see pressure and eventually when i figure how to connect it to my VFD. May be i need a relay or sth. This is the part that i always don't understand...






will post a video later, just uploading it now