FrankenVAC v2

Hi Everyone,

(so some of you might be asking "what the hell is he up to now, just cut some wood FFS. Well I did and as I am using a very small area in my brothers work shop, he got a little upset at the the dust all over his tools, new race motor, turbos, Brand new e-waste gates and other expensive stuff for his stupidly fast Lotus. Hence, the vac project has been brought up to the top of the list…)

Well, my day job is home automation, but it seems I work in a company that sells Whole Home Vacuums as well. (I am sure i mentioned this before, Oh well, Catchup time.)

So these vac’s are good for standard stuff, but once I added the Cyclone, there is not much flow / pressure. I don’t have the space (or $$) for a high volume system, but like I mentioned before it seems I work at a place that has lots of the old units “from upgrades”

So a bit of vac anatomy.
motors, there are two basic types “Flowthrough” ( where the “dirty” air flows through the motor to keep it cool) and bypass (where the “dirty air” is ejected out the side and a separate fan is used to keep the unit cool).
Flow through


Now the average small home vac has one of these motors, Like the one above, then you have the largest vacs with 2 motors

I would like to introduce the FrankenVAC

I got this idea from a Youtube show “hooked on wood” where I saw him making a system that was based around a 3 motor VAC system, CAMVAC. While watching it I had the idea to use some of the parts from work and make my own.

So a motor driving board, that you can barely see in the top left of the first picture, can control up to 2 motors, safely… NO, I am not going to dodge up some terminals and plug all three motors into one second hand board and turn it on to see what happens (for those that like to know the answers to questions like that, the magic smoke got very angry and spat the innards of a cap across the room and dumped the safety switch, or that is what i… think… might have happened…)

Sorry that is what I ASSUME would have happened as i would not be silly enough to do that… (magic smoke smells really bad)

So my version, After consulting with the relevant electrical engineers, is going to use two boards. One board to start two motors and the second board to start the single motor.

As i have access to quite a few of these old “upgrade” units, most of them have blown motors etc, I am going to create a Frankenstein VAC with its own cyclone barrel and eventually magnetic couplers.

I am going to cut down the “drive” unit so that it is just big enough to fit a bag attached to the central vac pipe, (you will see the idea in the next pictures), to protect the motors. This area is only looking to be about 500mm high. Just enough for the bag to inflate.

I have designed this to adapt onto the side of the barrel to induct the cyclone.

Its in 4 parts to make it easier to print and attached to the barrel it should look like this

the AIR path is as smooth as i can get it with my skill.

The barrel image shows the central tube, which extends to about 20mm from the top (and has a “spear” bag holder on the underside to hold the bag to protect the motors) so hope fully the smooth-ish entry and centrifugal motion generated will be enough to get rid of 90% of the dust, the normal vac bag will grab the rest.

To join the drive unt and the collection tub, as they are the same DIA, I am just going to pop rivet a collar around the outside of the collect unit, then bend inwards about 20 mm of steel on the top of the cut down drive unit, adding some weather seal squishy tape to seal the vac pressure. The collection unit should just slide over the drive unit and sit on the underside of the collection unit bottom. That should make it easy to remove the the collection unit and empty it.

I might have to go the magnet route for the collection hose to make it really convenient, but that can be version 3. lol

Oh and I am going to be using a mix of 38mm (standard vac hose, as I can get it from work…) and 51mm hose from the CNC. The inlets on the collection barrel are 51mm, so i might have to cad up a 51mm to 38mm Y.

More to follow


Place holder for more pictures.
I got bored last night on the couch, not exactly to scale, but good enough to visualise.


Sounds like you are having fun with the unlimited free resources at your disposal…LUCKY!

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Lol, yeah, this place has some advantages. Pay is not one of them…


Wait this sounds like 30 amps on a 20 amp circuit :wink:

What can possibly go wrong?


The was definitely a Home Improvement about this vac. I am sure of it.

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So not sure if I will use it, but I just knocked up an Magnetic adapter from VAC pipe (used on the machines) as its not a standard size over here.

But i reckon that CAD and CAD skills is just a matter of practice… lots and lots of practice
I decided to use an adapter ring that you can glue into one side to make printing easier, making a male and female part. I made it 0.5mm smaller than the available space between the two half when stuck together (height wise), might need to go 1mm smaller but I will see if I need the actual adaptor first

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After getting the original FrankenVac out of the workshop, it seems it only had one motor…
So maybe two would have been ok…

You cant complain about more suction right?

Hi Everyone, i hope you lives are steaming long and everything is good!

Ok, study, boat stuff and work are all severely cutting into anything else right now, but work has been a bit quite due to EOFY, so I have been started the gym super early so I could get to work early and do something.
(i hate early morning gym, but its the only way to “create” more time, after work is always taken and weekends are just stupid busy with Girlfriend & Social stuff.)

So my brothers Bambu x1 does a good job, here are those flanges.

Ok, please meet “FrakenVAC v2”.

the top Drum is the cyclonic-ish chamber, it wont be very good but will get a lot of the big stuff, the bottom barrel is where the bag is held on using that “spear” bag holder on the second flange. The first flange above is the riser, there is a bit of pipe that comes up to virtually the top of that top drum.(Those flanges are designed to screw through the wood to each other) That bit of wood you can see, it sits on the top of the bottom barrel with some gasket tape to seal it. Eventually i will use the CNC to make a new bit of wood with a nice round grove for the lip of the bottom unit it sit into.(with gasket tape to seal it). The top barrel will have a another ring internally to screw to and seal around.

Like i said, the cyclonic action wont be that great, but it should do enough to have the bulk of the material pulled out of the airstream. the fine dust should be caught by the bag in the second drum.

The two drums will be held together with over centre clips and i might even be able to get a couple of the wall mounting plates. As a general rule we don’t get hose back, so i will have buy them or make them, but i was actually thinking of a sorta french cleat design for it to sit on to. the over centre clips will hold it, but having the unit sitting on the mounting points at the back (you cant see them) , would make it nicer to push around.

Version 1 of that air diverter thing.

this neds a version 2 with bolt holes and seperate parts. Printing mistake by my brother. still that bambu is a pretty nice unit. This unit is actually four parts, the two parts either side of the metal, the external hose connector with 10 5mm magnets holding it on and the internal diverter, again with 10 5mm magnets holding it on. the internal diverter is probably what is going to change, i think i will make it so the diverter angles the air stream down about 5 degs so that it stays away from the top of the central tube.

Or i was thinking of adding a internal cone like this to force the air down. it would sit above the internal dust port and the internal suction tube would go through the centre.

This would force all the air down and around its only 100mm deep, then the air would have to rush up the gap between the pipe, still playing with this concept, will probably be version 3, but i do think it will need a baffle between the top of the air deflector and the top of the tube.

Normally there is no tube, and the suction is pulled via the top, when done like that a little downcomer tube is installed to get below the level of the inlet, which apparently gets over this problem, with my design the suction is via the tube in the middle. so NFI what is going to happen.


So dont you hate it when one your friends turns up, you show him you stupid project and he says “why dont you just put the motors on the top”
Then the penny drops, the machine start turning and your brain goes POP and the answer is sitting there?

Oh did i mention that with that one statement, he has nullified your last dozens of hours of physical work and probably triple that of mental work to get to that point…

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So due to time and money the FrankenVAC V2 is only going to have 2 motors. I just dont have the time to figure out the complexities of the heat and noise generated via the 3 motors. We will see how the suction is with the 2 motors and go from there.

I have decided to go ahead with the “light bulb moment” mods my mate gave me, but that will have to be FrankenVAC V2.5 lol

But todays questions is actually about ESTLCam, basically I am trying to create the grey bit in this render.
I have created the DXF and imported it into ESTLcam and created the “hole” in the center.
But for the life of me i can not figure out how to create the ???rebate?? around the outside.

I though it would be a “Pocket” but all elstcam does is fill in the centre all the way to the centre hole, when i want the rebate cut. I thought that i would
Anyone let me know what I am doing wrong?

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Island is what you are looking for. I am petty sure my write-up about it is on the milling basics page.


So you did, thanks!
And with a bit more learning, i am just that little bit smarter…


With FrankenVAC nearly sucking…, I thought i would have a look at some Y joiners.
After a bit of playing with cad, (its kinda relaxing.)

I was not happy with that, so a redesign and



And just cos i wondered if i could do it, the DYSON version.

Although, this one is really hard as i don’t know how to spiral in two directions from basically 2 planes (the inlet) to one (the outlet). maybe a helix, but that seems to only work in straight line, so a ??DNA helix??
I have worked around it, but is still a bit upset at the point where all the tubes join. I might have to stagger the inlets a little, that would be better for airflow dynamics etc, but not as cool. lol.
it will be interesting to see if i could actually make it work and print it.


Figured out some of it, now all three flow into the one chamber…

Wonder if it will print…


Hmmmm, i wonder if my brother will mind me experimenting with his bambo…

4 walls and 15% infill, 3h30min at normal speed.
we were playing with the “overclock” setting you have at the touchscreen, there is a “Ludicrous Speed”, wonder how much quicker it would be.

I will see if i can beg and borrow some time, i should wait till I get the MK4 upgrade.


and that bambu printer is pretty good


Just printed as fast as i could with standard PLA, not bad actually.

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