I have a BS-5S bandsaw, bought it around 8 years ago and it has served me well. I only use carbon blades as I cut a lot of tube and RHS so bimetals tend to shed teeth a lot.
The first thing I did for it was to add a coolant system. I tried a centrifugal pump first, but that didn’t last too long. The bandsaw makes a lot of very, very fine swarf which found it’s way into areas of the pump that the pump didn’t like and so the pump burnt out real fast.
After that failure, I bought a gear pump, these work well on the bandsaw as the fine metal swarf doesn’t find it’s way into the motor or bearings.. I’ve mounted the pump on the rear leg of the bandsaw stand, so it’s external to the coolant tub. The coolant tub is a plastic fuel container. I drilled a hole about 30mm from the bottom, turned up a spigot and bolted it in the hole then connected the tub to the pump via a plastic tube. The pump is powered by a 12volt power adapter.
I turned up a three way adapter and mounted it up by the base of the bandsaw hoop. Coolant is pumped up to the adapter, the adapter has one inlet at the bottom and two outlets above that. The coolant enters the adapter by the lower spigot and exits the adapter via the top spigot where it is fed, via a small retic hose, to the blade in front of the blade hoop. The tube is split and saddles the blade, so as the blade turns, coolant runs along the blade and on to the stock being cut. The coolant flow is far too much for the blade, so, I interrupted the line with a small retic tap, as the flow to the blade is reduced by the tap, coolant flows out of the midpoint spigot and returned to the tub.
Of course coolant splashes everywhere, so I had to make a few mods. The bandsaw table has a small lip around the periphery making an ideal basin effect, so I drilled a hole in the table, roughly where the material falls after being cut, turned up a countersunk drain, inserted it in the hole and locked it in place with a nut from underneath.
A 13mm plastic tube slips over the spigot on the bottom of the drain and feeds coolant from the table through a retic filter and a couple of rare earth magnets lying in the bottom of a couple of adapters between the filter and the coolant tub. That takes care of the coolant pooling on the table, however, some coolant flows over the side of the table behind the switch, so I bolted a small aluminium angle iron piece to the edge of the table.
The drain on the table clogs up occasionally, mostly after cutting wood or plastic, so that requires freeing up with a plunger every now and again. I also added a small plastic tray under the gap of the vice bed, but that has remained dry for the last eight years. Some coolant does escape the table when cutting tube, entering the tube through the cut and dribbling out the end. Not much I can do about that except place a bucket on the floor under the end of the tube being cut.
The coolant when it travels along the blade, shoots straight out the back, so, I removed the resting plate on top of the lower blade guide, fashioned another the same and cut a neoprene washer to fit between the plates and screwed them in place.
Here's a video showing how the system works.