Dust Collector for a Widebelt Sander
Advice on cyclones, filter types, ducting, et cetera for good dust collection on a wide-belt sander. January 31, 2012
Question
We bought a used 37" single head SCMI wide belt sander and we need to hook up a good dust collector to it. What should be the dust collector specs for good dust collection on this machine?
Forum Responses
(Cabinetmaking Forum)
From contributor H:
I have a 37" Timesaver single head sander. We run it with a dedicated Delta 50-760 1 1/2 hp collector that is fewer than ten inches from the machine. We even have it stepped down from the 6" port on the sander to a 4" pipe going to the collector. This is all theoretically undersized but does the job very well.
We've been running this for years with no problem at all. Recently I did invest in a better filter bag and that is definitely keeping the internal area around the belt cleaner but the stock bag did work well enough.
Normally we sand narrow material on the machine but recently we took a whole lot of 1/4" MDF down to 1/8". We hauled out several full approximately 30 gallon bags of the dust during the process. The sander and shop air remained clean and free of dust.
From contributor F:
If you get a copy of the machine’s manual it should have dust requirements in CFM's listed. Just remember that the ratings of most of the smaller single stage collectors are way overly optimistic - to put it nicely.
The stock bags on smaller single stage collectors, and even some of the bigger ones are usually 30 micron. This means they catch the bigger dust, but the smaller stuff which is the worst for you gets pushed right out into the air your breathing. Since you'll be attaching this to a wide belt all the dust coming out will be fine. I'm not a big fan of single stage collectors for sanders. The filters also usually get clogged with dust rather quickly, killing their already overstated performance. I'd personally recommend getting yourself a small cyclone for it with good filters. Although a little more expensive, you'll get a much better product for your application.
From contributor H:
I've not had good luck using cyclones on my sanders. The fine dust doesn't get pushed out of the airstream and ends up in the filter. You're completely right about the bag filters clogging. That is why we upgraded to a bag from American Filter Fabric. Their filter material is designed to cake to a point and then peel off on its own. We've had it three or four months and so far it has worked great. The bag is always soft to the touch when the collector is on.
From contributor F:
Normally I'd recommend checking your cyclone for leaks, as this is really important to keep the cyclone working the way it should. Small leaks between the cyclone and catch drum can lead to the dust flowing through. As you seem to have a setup that works already, may as well stay with it.
Another thing I'm surprised at is that the 1-1/2 hp sander with a 4" inlet is working that well for you. The PO if my machine had it hooked up to a slightly bigger four bag, (two upper filters and two lower plastic) bag collector, and it couldn't handle the sander. His machine always had a fine layer of dust on it plus you could smell the dust when it was running.
I run a 43" widebelt, with a 7-1/2 hp Torit that sucks everything I can throw at it. I haven't had any issues with the bulk of the fine dust not getting caught. It's actually so good at separation I've used it on a couple of occasions to make wood flour for a friend who uses it for end grain wood block work. I'll put a fresh bag in the drum and send a few pieces of solid wood through. A couple minutes and I can give him a small bucket of dust. So although you’re having good luck with your setup, it's just something I couldn't recommend to anyone else based on my experience.
From contributor D:
I put an Oneida 5hp cyclone with an upgraded cartridge filter on my 37" widebelt a few years ago and it works great. I too had doubts about how well a cyclone would separate fine dust, but I gave it a shot and was pleasantly surprised to find it works much better than the four bag machine it replaced. Not to mention it's much easier and quicker to empty the drum than the bags.
From contributor H:
To contributor D: I take it you have one of Oneida's aproximately 6' tall cartridge filters? If that is the case is it staying dust free or do you have to remove and clean the inside of the pleats occasionally?
From contributor D:
The dust doesn't seem to stick to the pleats in the cartridge, and what little bit of dust that doesn't end up in the drum drops out into the metal pan under the cartridge. We'll check it every few weeks, but it rarely has more than a fraction of an inch in it.
From contributor L:
We have an industrial level cyclone and after filters. The cyclone removes almost all of the dust before it gets to the filters. The filters automatically shake down five minutes after the collector is shut off. If you get a collector large enough to handle your max load be sure to design your piping system for the way it's actually used. Don't do the trunk line system that factories use where it is assumed all gates are open at once. If you do that with only one or two gates open and the flow is into a larger trunk line you won't have enough air volume to keep the stuff at a high enough velocity to keep it from dropping out in the pipe.
The same thing applies to your cyclone. It has to have enough flow to work. If you have only one 4" gate open and a cyclone with a 8" inlet you won't have enough air flow/velocity to spin the dust out even if you have enough HP on the fan. Clean air type fans are more efficient than the typical paddle fans but must be on the clean air side of the filters. If you can, put the cyclone and baghouse outside and equip the system with blow out panels, it's safer and quieter.
From contributor F:
You can use the trunk line style collector setup if you plan ahead. On my system the table saws are un-gated, so they're always open. This equates to an 8" and 4" being open constantly so air flow is not adversely affected. With this setup I can run two other machines with really good performance. I'll generally try not to use other equipment when I'm using the sander to keep it at max performance and because it pretty much maxes out my panel with both going anyway. I think the key point that Contributor L made is to make sure it's designed correctly for your use. I had a local company do my layout for me, as it was more math than I really cared to tackle.
