Picking up on the idea of converting the standard Harbor Freight Dust Collector with a separator and Thien Baffle as described by KDC68 here, I did my own build based on KDC68’s design. I’m not going to go into the repetitive details of my build, but will point out some things that learned in the process that would have been good to know at the beginning.Some overall notes:
- I used the same 5 inch to 4 inch reducer” that KDC68 used. It is a press fit into the garbage can connector I used as the weight of the motor holds it down. I could not find a 4” S&D connector that would fit up with the female end of the reducer.
- I had a hard time figuring a way to cut the 4” holes in the 1/2” MDF for the Thien baffle. All I had was my Porter Cable 7518 router, which is a bit much for doing small circular holes. Eventually I rigged up something that worked, but there’s got to be a better way out there somewhere.
- I did not have a planer to create 1 3/8” mounting board like KDC68 did, so I glued together two 12 1/2” x 20 1/2” 3/4” MDF boards to create the mounting platform. I routed 2” long 5/16” slots in this to allow this board some leeway after being mounted.
- As KDC68 did, I raised the platform for the bag attachment 3 1/4”.
- This is definitely NOT a one-man operation as mounting the beastly heavy motor to the uprights is nearly impossible with one person. I did all the prep I could before enlisting help. I spent alot of time trying to determine the needed mounted height of the blower assembly. I determined the best way to give me some flexibility was to cut 2” mounting slots for the lag screws holding the mounting board. You can see the 1 1/2” thick MDF mounting board with the slots routed into it in a picture below.
- I mounted the motor to the board, put on the 5” flex pipe pieces on top and side (pieces cut from the pipe that came with the DC), then put the whole thing on top of the garbage can. The weight of the motor held it in the fitting on top of the can. I then clamped it to the 4×4 posts on two sides and used a hammer to push it up into position, where I then drilled pilot holes for the 5/16” lag bolts that attached in the slots. I did get some help at the very end to help position it correctly.
- I annotated the pictures with some dimensions so you can see the important ones.
- If you can’t see from the pictures, the mounting board was 37 1/2” off the platform, and the bottom of the fan assembly was 37 off the platform.
- The mounting board was 2 sheets of 3/4” MDF 12” x 21” glued together, then slots were routed for the motro mounts.
- I did buy the upgraded Big Horn 1-micron filter bag from Amazon.
I was skeptical that the whole assembled support “tower” would be stable and not sway back and forth. But surprisingly the heavy weight of fan assembly onto the garbage can makes it sit down into the connector to the can, so its movement side to side is limited. The 4×4 posts are anchored at the bottom with post anchors (2 for each post), so the entire apparatus is quite stable in the end.
I wanted a way to be able to turn on the DC when I’m standing at my table saw, so I wired a switched outlet onto the tower and plugged the DC into it. I then turn on the DC switch and control the on/off with the switch box laying on my table saw. I know this is a bit ghetto, but it works and I may upgrade to cord from Romex to some industrial cord material.
I did have a 20 amp breaker installed (you get two by running just 1 12-3 wire run from main panel) to power this, along with a 30-amp 220 outlet for my Unisaw.
When I first fired up the DC, I was cutting some MDF and immediately noticed some fine MDF dust leaking from the rectangular connection between the motor housing and the waste bag/filter housing. There was a gasket for this when I put it together, but it had a loose fit. Should have probably made my own gasket. Anyway, to correct this I put some spray foam and caulk into the cracks around the connection.
So far the DC works great – good suction and very little leakage, so I’m quite pleased.