Dust colletor re-design/build

[P. McKinley]

Some of y'all will remember my attempts at designing and build a dust evacuation system for my basement shop. The system worked fairly well, but some inherent design problems(of which I was warned by a few folks) cropped up and caused some issues that prompted this re-design. In short, the main issue was water being sucked into the blower which has now rusted the impeller and drive shaft resulting in a loud "grinding" noise when operating. I now have to remove the impeller from the shaft and find/fix whatever has caused the noise. The screw that holds affixes the impeller to the shaft is rusted solid, so that has to be dealt with as well.

I still need to make a more air-tight lid for the top, but so far I'm pretty happy.

However, the new dust collection rig has been fabricated and assembled and it works quite well.... much better than its predecessor. I purchased an old stainless steel restaurant counter top from the junk yard for $ 10.00 and cut it up with my angle grinder, then cleaned up the edges on the grinder. My neighbor then welded it all air/water tight. This design was adapted from one that Ian Hall uses in his shop seen here: http://www.bladeforums.com/forums/s...ow-would-you-do-one?highlight=dust+collection.

I'd appreciate comments and suggestions.

First, the old rig:





Now the new:











with spark curtain removed:










and the inside of the rusted blower:


-Peter

 

[Jonathans]

Very intriguing. Can you please post a couple of pictures of your collection box?

 

[P. McKinley]

The removable water trough is the collection box. All the heavy stuff falls into the water. The remaining lighter debris is then sucked up and over the partition, through the blower, and out of the house through a wall port.

 

[Josh Rider]

It looks great! I had a hard time searching threads for a good metal dust collection unit.
Is there a wip/ plans anytime in the future?

 

[Stacy E. Apelt - Bladesmith]

Very good improvements. I may steal the removable trough for my new shop build.

 

[Frank Niro]

Thanks for this Peter ! I had to make a quick unexpected move and was already thinking about a better dust system than I have !
Frank

 

[Lo/Rez]

For some reason I'm not getting the pics.

 

[HSC ///]

I've been to Ian's shop and I can tell you that his system works quite well and captured most, if not all of the dust form the grinder.
Yours looks like it will work very well too.

 

[P. McKinley]

Greenjeb - I didn't take a lot of photos of this process so I can't really do a proper wip. I can tell you that a lot more went into this project than just cutting up and welding a bunch of steel plates together. I spent a fair amount of time doing some math calculating volume and such. I also built a crude cardboard mock-up to help with placement and the workbench modifications that were needed to accommodate this contraption.

This project started when my previous system, because of the design, sucked water/grit into the blower and rusted the motor drive shaft and bearings. LOUD!! So, if I was going to rebuild the motor, I might as well take the opportunity to re-do the entire system.... better. I've had several conversations with folks who know a lot more about the physics of this than I, and the consensus is that the standard design used by many knifemakers is all wrong - including my previous version. My Wilton grinder, and that fact that my shop is in the basement present some special needs if the goal is dust evacuation . Ian's set-up just made sense, no cyclonic effect(that the standard system has in reverse), more complete capture of the dust and fine debris that rides around on the belt through the grinder cowling and back out the top into the air(my chest), I can more easily change the sludge water, and its more compact.

This redesign isn't the end-all, beat-all of systems. Ideally, there would be a suction port added somewhere to the back of the grinder housing to catch even more of that "belt dust", as well as a return air system(also ported into the grinder housing??) from outside the house rather than risk drawing in CO2 from the house furnace in the adjacent basement room. But, what I've put together works like a charm and is a considerable improvement. I can always add those additional features later. I'll likely need to fine tune the system a bit, but I'm happy. The blower will be back with new bearings on Monday and I'll be back in business.

-Peter