My Dust Collection unit is the 2HP model from Harbor Freight, and I have to say, it's been worth every penny. I got it on sale for $159 (reg $229), and I think it's hard to beat it's performance for the price. I would advise that you update the filter bag to something better than the standard 5 micron that the unit comes with.
Pipe and Hose:
The unit is connected to the machines with 4 inch thin-wall PVC sewer and drain pipe. This PVC pipe is is easy to install and works really well. I have a blast gate at every machine, and can only have one open at a time (for optimal performance). After the blast gate, I use 4 inch flexible hose (PSI Woodworking D50A 4-Inch Flexible Dust Collection Hose) to connect to the machine. I bought this hose from Amazon, and while it is considered the lower end of flexible hose, I found it to work quite nicely. The flexible hose is strong enough and has stood up to the abuse that I have put it through.
I use a garbage can lid pre-separator. A 2-stage dust separator converts single-stage collectors into 2-stage units by allowing sawdust to drop out of the main airflow and into a container before reaching the impeller. The model I have is made by Jet and was purchased from Amazon. It really does a nice job. I'd say I empty the garbage can 4 times for every 1 time I empty the collection bag on the DC unit.
Since my unit is only a 2HP, I can get away with a remote control that is designed for christmas lights. I have the heavy duty one that is rated at 15amps, and I haven't had any problems so far. It's the best $12.95 I spent on my DC system! The remote is a little bit of hassle if you don't keep track of it, but compared to alternatives, it's been an excellent solution.
There are Long Range Dust Collector Remotes that trigger larger machines. They can be bought for about $65.
4 were reviewed in the latest issue of WOOD magazine, all faired equally.
Shop Fox D3038 - www.Shopfox.biz
Pen State LR110-3 - www.pennstateind.com
Fernbrook Smartswitch DK2202XT - www.dnet.net/frnbrook
Long Ranger - Multigate - www.pennstateind.com
Blast gates with trigger - $11
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