DIY workshop dust collector... I'm gonna try to make one!

[newts]

Don't underestimate lung damage from short term usage, fine dust is the enemy & any filters in the vacuum will need changing as regularly as if you were using bags (as part of the bag or separate filter).
Cyclone is very good for collecting the voluminous waste from machining. Planing & sawing tends to be larger particles, sanding produces mainly very fine hazrdous dust which is also very flammable.

 

[MontyVeda]

Don't underestimate lung damage from short term usage, fine dust is the enemy & any filters in the vacuum will need changing as regularly as if you were using bags (as part of the bag or separate filter).
Cyclone is very good for collecting the voluminous waste from machining. Planing & sawing tends to be larger particles, sanding produces mainly very fine hazrdous dust which is also very flammable.

which is why most advise a belt & braces approach, vacuum the dust away and wear a good dust mask

 

[newts]

which is why most advise a belt & braces approach, vacuum the dust away and wear a good dust mask

Indeed, a mask is important as many vacuum/extractors exhaust through alot of fine dust due to blocked/inadequate filtration.
This mask is very comfortable to wear for longer periods.
https://www.screwfix.com/p/jsp-force-8-mask-respirator-with-press-to-check-filters-p3/1863f

 

[MontyVeda]

Indeed, a mask is important as many vacuum/extractors exhaust through alot of fine dust due to blocked/inadequate filtration.
This mask is very comfortable to wear for longer periods.
https://www.screwfix.com/p/jsp-force-8-mask-respirator-with-press-to-check-filters-p3/1863f

I went for the Elipse one... same price range and plenty of good reviews to back it up. I'm yet to use it for a prolonged period but it fits my chin and seals well. If it doesn't suit my needs in the long term, i'll give that one a try. Thanks

There's also a wide range of HEPA filters which I'll have a look at fitting to the outlet of the dust collector. Of course not all are created equal but a bit of trial and error...

 

[Electric_Andy]

EDIT... a question for y'all... will it be significantly more efficient if I keep the length of the hoses to a minimum?

As I understand it, longer pipe must be thinner to avoid significant suction loss. Here is an equation, I don't really understand it


"Delta_p = 27.8 * l * q1.75 / d4.75

Where delta_p is the pressure difference or vacuum loss you are looking for in kPa

l is the pipe length in metres

q is the volume flow in the pipe, in litres of free air per minute

d is the internal diameter of the pipe in mm.

Change the units and you change the 27.8 multiplier."

 

[newts]

I went for the Elipse one... same price range and plenty of good reviews to back it up. I'm yet to use it for a prolonged period but it fits my chin and seals well. If it doesn't suit my needs in the long term, i'll give that one a try. Thanks

There's also a wide range of HEPA filters which I'll have a look at fitting to the outlet of the dust collector. Of course not all are created equal but a bit of trial and error...

We only have one set of lungs & not easily replaceable. I spent much of my 20's in joinery workshops/ building sites with inadquate dust collection.
My lung capacity is reduced as a direct result, that's my excuse for being a very poor climber on the bike.
An M class extractor is a requirement in any commercial enviroment, but i still see brick & wood dust being spewed everywhere when i'm visiting building sites as part of the current day job

 

[MontyVeda]

As I understand it, longer pipe must be thinner to avoid significant suction loss. Here is an equation, I don't really understand it


"Delta_p = 27.8 * l * q1.75 / d4.75

Where delta_p is the pressure difference or vacuum loss you are looking for in kPa

l is the pipe length in metres

q is the volume flow in the pipe, in litres of free air per minute

d is the internal diameter of the pipe in mm.

Change the units and you change the 27.8 multiplier."

Thanks for that.

with so many bits of vacuum hose to play with, I can lengthen them as needed... so what I've got is the vacuum parked next to the dust collector and just enough hose to connect the two (26")... and with the dust collector parked close to the bench with the sanding machine on, just enough hose to reach it's vacuum outlet (20"). Adding on the extra bits will give me up to 8 foot so plenty when using the planer and router too.

I'll post some photos in a day or two.

I don't understand the equation either

 

[MontyVeda]

Not finished it yet but lots of progress.

to recap, I gathered together a load of bits and bobs from which i'd concoct a workshop dust collector:

The beige bucket is where all the action happens which means it needs a hole (dear Liza)

or three...

I had a blond moment when marking out the inlet. The pipe going through the hole should point slightly down, but i made it point up

I bodged that later after spending most of the day trying to find the bits i needed to make a pressure release valve.

Starting at the top;

• a bit of drilled dowel glued to a washer with an M4 grommet in it.
• a big rubber washer
• a spring from my old washing machine's dampening block
• a bit of a waste pipe fitting
• the wheel from a broken pizza cutter
• two tap washers
• the screw from a bike light handlebar mount
• a bit of a broken one-cup caffetiere

I'm terrible for not throwing stuff away, and in the case of this valve, I'm glad I don't because it all fits together so well.

The rubber washer will be glued in the underside of the hole, and the white bit of pipe fitting glued to the top of it.

The spring holds the pizza cutter against the washer, keeping the hole shut. If the inlet gets blocked, air pressure should (will) open the valve to stop the big bucket from collapsing, and the spring shuts it again. The screw from the bar mount means I can adjust the pressure on the spring.

Bodging the inlet pipe...

...and ready for assembly.

I'm using sikaflex elastic sealant to fill the gaps around the inlet, which i think should be ideal. The outlet (top) will just be bolted in place and the valve holds itself together.

The sealant around the inlet pipe is going to be thick so I'm building it up a bit at a time, and once all that's done, the bucket needs gluing to the lid of big brewers bucket (sikaflex again)... and when that's cured, I'll cut out the middle of said lid and see if it works.

🤞

 

[slowmotion]

Looks good. You ought to check that Sikaflex has good adhesion to the type of plastics of your inlet pipe and the bucket. Some plastics, eg polyethylene, are notoriously tricky. If possible, I'd try and reinforce that junction with some kind of extra mechanical support and not just rely on the mastic.

 

[MontyVeda]

the adhesion looks OK so far... but time will tell.

 

[MontyVeda]

Looks good. You ought to check that Sikaflex has good adhesion to the type of plastics of your inlet pipe and the bucket. Some plastics, eg polyethylene, are notoriously tricky. If possible, I'd try and reinforce that junction with some kind of extra mechanical support and not just rely on the mastic.

Thank you for this.

The sikaflex is sticking to the inlet pipe and beige bucket, but it's not bonding to the lid of the brewers bucket. I wouldn't have checked with a blob on the lid if you hadn't advised me.

Currently investigating a plan B, C and D 🕵️‍♂️

 

[slowmotion]

Thank you for this.

The sikaflex is sticking to the inlet pipe and beige bucket, but it's not bonding to the lid of the brewers bucket. I wouldn't have checked with a blob on the lid if you hadn't advised me.

Currently investigating a plan B, C and D 🕵️‍♂️

Plans B, C and D are what make this stuff fun!

 

[newts]

Hot glue gun might work?

 

[MontyVeda]

Plans B, C and D are what make this stuff fun!

Absolutely!

Plan B... a bead of gripfill (non-flexible) on the lid, and seeing if the flexible* sikaflex will stick to that.
Plan C... replace the plastic lid with a wooden one and use that as the interface between the two buckets
I haven't thought of plan D yet.

Hot glue gun might work?

It might but haven't got one anymore and didn't get on well with hot glue when i did have one.

* the lid is very flimsy but the beige bucket is rigid, so I doubt a rigid bond wouldn't last very long when the lid is repeatedly removed.

 

[Poacher]

Looks like you're sorted, @MontyVeda, and job's a good 'un, but if anyone else wants a dust extractor, act fast , 'cos this one comes up tomorrow at a local auction. If need be, I can store it for future collection.
Arthur Johnson & Son | Machinery & General Sale | Lot 2530