Thread: Bandsaw: dust extraction modification; Leda or CT SBW-4300CE style

I ran a few tests with double sided tape, timber zero clearance insert and some rubber to change the airflow.

Pic 1 - quick test of idea. The wooden block took a whole 5 minutes on the bandsaw to make.

Pic 2 - next on the agenda was to make the dust pickup entry in the door. This was a simple cut and bend job to create a hole.

Pic 3 - the hole is done

Pic 4 - now the hole is there I need to guide the dust somehow...

Pic 5 - under the watchful eye of the shop dawg, I put together a pine frame joined by 4mm dominos.

Pic 6 - frame fitted and a wooden baffle is attached to the door with double sided adhesive.

Pic 1 - some door seal helps to make a good seal.

Pic 2 - a piece of pine is slotted to sit on the steel flap

Pic 3 & 4 - end pieces help direct the airflow across the guides.

Pic 5 - the test piece

Bandsaw is cleaned so I can tell what the results are like.

Pic 1 - I made a number of cuts across a log to generate dust.

Pic 2 - the table top had more dust but a gust of wind blew it off.

Pic 3 - the guides were surprisingly clean, very happy with that. Normally they would be covered in fine dust.

Pic 4 - some dust escaped past the single seal.

Pic 5 - a second and third seal were put on the door to create stop any dust getting past.

Pic 6 - a better dust collection method by far. I'm pleased with it.

As far as I can tell, the only dust getting away is now on the top of the table. The blade creates a downdraft that spreads dust around. At some point I may try to make a pickup that sits around the base of the column, as that is where the dust sprays out from.

It is not a perfect system but is reduces a huge amount that used to get under the table. I am guessing that more than 90% is caught now.

Thanks for the experiments Groggy, I'll be needing to do something similar when I finally get my BS in my new shed so this is very helpful.

What would stop an opening being made in the entryway to the BS DC manifold the size of the red box or the blue box?


It seems like a bigger opening would sweep the entire area under the table and capture all the crap in that aread and might even do away with the need for a surround?

In terms of the downdraft from the blade it's interesting to see where Bill Pentz puts his third BS DC inlet - attached to the top blade guides
Bill's Cyclone & Dust Collection Research - Ducting

Thanks for the link Bob. I toyed with the idea of using a bit of PVC tube from where you put the red bit up to the table insert. After a bit of thinking I decided mounting it would be a bear and it would not draw as much air as the method I eventually used. Also, that piece of steel looks like it is needed structurally to hold the weight and torque of table adjustment.

I am very happy with the under table collection now, and may look at some magnetic sign material to cover the gaps around the pillar where the blade runs up the side. This may help it draw more from the top down to the lower collector hose.

The top I was thinking of something just like what Bill has on his site. A 3.5" flex tube mounted to the back of the blade guard and hopefully, if I can, some type of fitting that sits about 10mm around the entire guard with about 50mm at the rear. The dispersal of chips seem to be mainly at the back in a 'V' shape. I guess it would be possible to use a shroud similar to the LV pickup shown below, the magnet would be handy for use on other tools like the drill press.

Who designs these things anyway? It is a useless implementation, one designed to get past a government requirement without coming close to meeting the intent of the specification.

Dumb question time. Can you still change the blade easily?

I made a dust hood to fit under the table it catches most dust, I grabbed some 4"PVC pipe about 10" long, removed my blade and lower guides heated up the pvc using a heatgun, donned the gloves and pushed the pvc under the table(horizontally).
Being hot the pvc moulds to the shape(may take several heatings and pushing)of the area, once it formed the shape I cut out an area big enough for the guides and blade to fit in and enough to allow a good air flow.
On the inside end of the pvc I made a wood plug from mdf to block the air so it sucks in from and around the blade guides and table trunnions. Its very easy to remove as its a jam fit.

Originally Posted by

Dumb question time. Can you still change the blade easily?

Yes. The wooden shroud is attached and comes away when you open the lower door. The zero clearance plug just slides out. I will make a few more of them for different size blades.

I had a look at this same style of mod on my bandsaw a while back, I used to have sawdust piled up around the guides and along the top of the lower wheel cabinet ....this is what I did https://www.woodworkforums.com/f27/du...e-table-92444/
I also thought of cutting away the area Bob marked in red/blue but decided on modifying/adding to the door instead (non structural) I cut the corner off the door inline with the angled metal section inside the cabinet which opened up a large area to allow more air to flow.
Basically I made a two part shroud which fits around the guide wheels and up as close to the table as I could get it, this top half uses one bolt to hold it in position, the lower half is welded to the door and collects that which comes thru from the top and directs it all into the top 4" collection point, I added a strip of sheet metal to the lower cabinet to direct the sawdust into the lower 4" collection point with a strip of rubber in the door which butts up to the sheet metal forming a seal.
A vast improvement over what it was, I never have anything around the guide wheels or along the top of the lower cabinet the stuff that hits the table is still a problem as it ends up on the floor, that solution will probably take the shape of a third collection point and a large offside chute, but that's something for later.....

Pete

groggy,
Might have to test the mod out with some more acrylic, that definately makes the job look a fair bit cleaner, now all you need is a small hose on around the top bearing assembly.

On a side note is that one of the new blades on that log - it looks like its making light work of the timber

Salty

Salty, the blade is the same one left there on Saturday. Bit of a slow feed rate but it did a pretty good job of it.

I gave the saw a run for about twenty minutes cutting up some redgum posts. The before and after pile of timber is shown. I was very happy with underneath the saw dust collection, an amazing difference.

I did nothing to take the photos other than open the doors. A small amount of dust on the sill of the lower door and a bit of a mess on the table. Given the timber was damp on the surface and had some rot, dirt and loose material the table stuff was hardly surprising.

Pic 1 and 2 - the task
Pic 3 - a bit of a mess on the top, more dirt than dust
Pic 4 - some dirt in the door that I think pulls down through the top of the door.
Pic 5 - clean guides after all that cutting!
Pic 6 - For those who have this style of saw, they may be surprised at the back of the saw still being reasonably clean, normally it is covered in dust. I *think* this may be because the air is drawn over the guides and into the door and catching the dust dropping off the table to some degree. Whatever the reason, it is cleaner than normal too.

SWMBO will be very pleased.