The 9-15 - Open Source Vacuum Project

[Brady Watson]

OK...here's the deal. 2yrs ago Bill Palumbo & and I came across a great source for vacuum motors that exceeded the performance of a Fein T3 @ 25% the cost. There were 2 models...One did 10.5" Hg & 95 CFM and the other did 9.5" Hg & 95 CFM but this 2nd one was a bypass motor, meaning that it could be used in series with the another motor of the same model...meaning that you could have one vac sucking thru the other to get a higher Hg" rating. There are many projects that I have worked on in my own R&D department & this is one project that is ripe for exposure to this group...so I am letting it out there for the good of the community. I briefly shared some of this information at the Jamboree this year, for those who attended. Before I get into technical aspects of this project, I want to make a few things clear, that you must intrinsically accept if you choose to undertake this project for yourself:

1) If you are not good with electricity, spend a few bucks and get an electrician.
2) If you are really, really lazy and you want every little thing spelled out for you every step of the way, this is not for you.
3) This is as much a learning process as it is a means to an end. You will learn much as you build this setup, and be rewarded with a powerful vacuum powerplant for your effort.
4) This is NOT a replacement for a professional vacuum system made for production work, although it's performance approaches some of these units.
5) Do your homework, your OWN research and use your own ingenuity to make YOUR version better than what I have come up with.
6) If you build a system using any of these motors, please post a picture to the group to inspire others.



Here's a single VBTST6460VM being tested



Single motor vacuum performance via Summit Racing gauge

OK...the name...the 9-15 stands for 9" Hg or 15" Hg from 2 vacuum motors. I will be talking about the bypass motors only. These motors have gone up about $10 since I bought them, but they are right about $100 each. You can purchase them through the very nice & knowledgable gentleman @ http://www.lighthouseenterprises.us/imperial.htm I believe that the model number is: VBTST6460VM They do 94 CFM & 130" H2O (about 9.5" Hg) each. Each motor is a 3 stage unit that compresses the air 3X to get higher suction. By having one motor sucking thru the 2nd motor, you essentially double the suction, and loose a tiny bit of CFM in the process. In my testing, I found that running both motors in parallel, both motors together pulled about 9.5 to 10" Hg with about 180 CFM (I have no way of verifying CFM, but it moved a lot of air). These are industrial grade units by the way, not some Eureka replacement piece of junk. Running the motors in series (one sucking thru the other) I measured 15 Hg" with about 1/2 the airflow. Probably about 90-100 CFM if my math is correct.

Being the kinda guy who 'wants it all' I didn't want to create a system that was either only 9" Hg or 15" Hg...what if I could do BOTH? Depending on the job, one may need more CFM and less suction & another might need that whole 15" HG to hold down small parts. I wanted to be able to switch as I needed to. Enter the 9-15...I started with the idea of housing each motor individually in a pod of sorts that could be tied into another pod by unplugging and plugging in tubing. I made a plywood box just for testing the concept, complete with automotive type filtration, and 'exhaust pipe'. Entire box was dadoed and cut courtesy of the Bot...and holes drilled in the RIGHT spots for the motor to mount mid-ship. Don't ya just love having a bot around?
This box with ZERO sealant, tape etc, with one quick-grip clamp pulled 7" Hg which is not too shabby for a non sealed box. It was a good little unit, but not quite what I wanted...



Plywood 'pod' created on Bot with only one clamp to hold it together while running tests



This pic for you nudges that are going to ask if it did 7" Hg with the lid off!

Here's the drum vac or the 'Typhoon'...This was based on a 15gallon steel drum and the housings were sealed into the lid allowing easy access to the filter...The only problem was that there really was no easy or elegant way to switch between 9 and 15" Hg with the drum configuration:



2 motor Typhoon concept



Single motor Typhoon test assembly

Several months went by working on & off on the project, still not arriving where I wanted to on it...After a good intense 'strong coffee thinking session' and about 47 sheets of paper scratched out, I finally came up with a theoreticaly system that would 'do it all'. A trip to HD and a pile of PVC parts later, I cobbled together a working model of the 9-15:



Downright ugly, ain't she?
...yes I am aware that the top tube is not connected...wise guys!

By opening and closing valves the vacuum is directed in either parallel or series, yeilding 9" Hg & 200 CFM or 15" Hg & 100 CFM. Pretty neat, huh? You guys can figure out a more eloquent way of packaging the entire assembly. This config was really just setup to prove the concepts (and they DO work as planned!) As it is one motor sits lower than the other...You can do better....



The 9-15 in 9" & 200 CFM mode

Doing small parts and need some extra oomph over the 9" Hg setup? No problem. Turn a few valves with the motors off, and in seconds you're ready to go:



9-15 in 15" Hg & 100 CFM mode

Examine the photos carefully to get the full concept. It's pretty simple once you understand what is going on. I know that many of you can improve on my design & concepts, so if you build one of these, post it up for the good of the community...and to keep me interested in sharing projects like this...it's nice to see my 'babies' come into existence
I'd love to have the time to fully document each step, create plans or a kit...but I just don't have the time to do that or walk someone thru start to finish (read my 6 requirements in the beginning). This is a really worthwhile project for you guys that like to tinker and do clever things on a shoestring budget. I'd much rather have my R&D be used than shelved or saved for my book.

I've since moved on to a new vacuum system that is more suited for production work. Meet 'Becky', a Becker VTLF250SK 25" Hg & 175 CFM!:



Warning...small animals and loose appendages may get sucked in without notice!


-B

[Pascal Riendeau (Paco)]

Cool! Perfect timing! Thanks a bunch for sharing Brady!

I could use one detail; fittings for the motor intake and out to the PVC plumbing...? I can see you've use cast iron flange for the intake (are they glued?) and a PVC reducer for the motor #1 out (fit readily?)... in other words; are the plumbing connections standard size(s)?

Noisy?

[Brady Watson]

Thanks Paco.

You are correct. The motor mounts against a cast iron flange, but there is a silicone 'vacuum gasket' in between. Lighthouse should have an appropriate gasket, or get a hi temp silicone O-ring from McMaster, MSC etc. The flange is attached/sealed via C-clamps for my demonstration, but If you really want to do it right, machine a 3/8" AL disc/donut on the bot & tap holes to bolt the cast iron flange to it. Then use that AL disc for mounting & clamping it together. The motors DO get toasty, so you need something that won't melt.

In open air, they are as loud as any other shopvac. Add a little foam bedding material to the enclosure & exhuast baffle and it quiets down substantially. You can see a pic of the bedding material (some call it egg crate foam) in the wooden box pic.



-B

[ralph hampton]

I like Becky best... but how many amps, how many dollars?
R (:

[Brady Watson]

ShopBot sells the Becker pump. Check out their price list. It is much cheaper than buying directly from Becker and you get all of the plumbing etc. It's a 10hp 3ph 230v motor.

-B

[Scott Smith]

Hmm, My pool plumbing has a 2” pvc 3-way valve for the skimmer / main drain selection. If they work with vacuum you’d only need 1 valve between the pumps. Google “Jandy valve”. Looks like Jandy also makes a check valve for the pool industry. Might get it down to one 3-way valve and a check valve.

Just some thoughts,
Great gob Brady,
Scott

[Scott Smith]

Scrap the check valve idea. Don’t think that would work.
Scott

[Brady Watson]

The plumbing works...and I doubt there is a simpler way to plumb it than what I did. Your job is to make it look all pretty...or not. It works as is...that's the important part. The check valve can be used for something else...which is an entirely new thread & project altogether.

-B

[Pascal Riendeau (Paco)]

Brady?

It still need a filter at the intake right?

Is that a 2" to 1-1/2" reducer at the exhaust motor #1 to motor #2?

Roughly, what size is that setup (above)?

You said it get somewhat hot; how does the PVC plumbing take the air temperature from the exhaust?

Why this particular motor?

I know you mentioned you don't want to hold my hand for the tinkering of this project but I can't order the motors if I'm unsure about the fittings... I believe you're the one to answer for that since you built one. Thanks a bunch in advance!


I was just about the order a second Fein T3 (still shopping) but this could be better.

[Brady Watson]

Paco,
Yes...1.5 to 2". It gets hot @ the exhaust, but it didn't melt the PVC...but I didn't run it all day long in 90° heat in a production environment. It might not be a bad idea to take a stroll down to the automotive store & get a length of 1.5" exhaust pipe. That stub you see in the wooden box pic shows a 1.5" automotive stubby fitting. It slips right on & a hose clamp seals it off nicely. By putting a longer metal tube there instead of going right to PVC, it will act as a buffer zone for the heat. Of course doing this changes the route of the tubing. Do not let the tubing keep you from doing the project. Hi-temp Silicone tubing can be used for those 'hot connections' and slight differences between metal & plastic diameters...here I am...doin' your R&D for you again...LOL!


If I had to guess (disassembled right now) it is about 24" tall or so.

The motors are CHEAP for the performance they give AND made for series operation. You cannot do what is being done with the 9-15 with just any old motors...they have to be BYPASS motors and both should be identical.

-B