Seeing as how the vanes are reversed on those two impellers, which direction does the motor turn? are the HF and Rikon motors reversed from one another?
Seeing as how the vanes are reversed on those two impellers, which direction does the motor turn? are the HF and Rikon motors reversed from one another?
Really? Funny, seeing as the HF unit runs CW.
Both the Rikon and HF units are CW in their rotation (as well as Shop Fox W1685, W1666), as determined by the positioning of the motor on the housing. Units such as the Jet DC-1100, DC-1200, Delta 50-850A, Powermatic PM1300, are CCW units.
Last edited by Kevin W Johnson; 05-31-2012 at 1:05 PM.
Kevin, if your HF blower is a clockwise configuration running a forward inclined blade you really improved it when in effect you changed to the more proper BI configuration. I have never seen a DC run a FI fan and would be surprised if the others you mentioned used FI blades. They will likely run fans made in the same direction as Rikon. FI fans are meant for low rpm, high volume but low pressure applications while BI fans are medium volume at higher pressures which is why the diameter is larger. The HR unit may pull great CFM unrestricted but the flow will drop dramatically when restistance from pipes is added. Turns out you did absolutely the correct thing in swapping the impeller. The original one is not correct for the application IMO. Dave
John, you were way ahead of me. Didn't look closely enough at the pictures and it didn't occur that HF would spec that fan. Given that the attachment bolts are on the same side of the curve as a BI fan it seems like it should be run that way. Bracing and bolts are generally on the back side so as not to cause more turbulence in the flow. Dave
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The most expensive tool is the one you buy "cheaply" and often...
Based on your amp readings and the pictures of the impellors, something weird is going on. Assume the fan wheels are identical (one appears to be designed for CCW and the other for CW rotation, but ignore that for a moment, they are both the same "style/type"). Based on the diameter increase, 12/9.75, you would get an increase in flow of 86% (varies with the cube of diamter change). Consequently, the amp draw would also increase at least this much (I think more, but I can't remember the relationship). Your amp draw only increased 14%. Maybe the HF was terribly inefficient, especially if it was turning backwards as discussed previously.
Mike
Last edited by Michael W. Clark; 06-01-2012 at 1:15 PM.
Michael, don't you think the bag restriction is at play here. The new impeller can only push so much air through the bag. I'm assuming no flex is attached to the inlet so pipe restrictions are not an issue. Have you ever seen an impeller run as a forward curve in a DC? Dave
Good point, the system resistance overall will increase with the increase in flow (SP increases with the square of the flow change). I have never seen an FI wheel on a DC. In larger systems, you would see a radial or radial tip in this application due to the fan being on the dirty side of the collector. Usually BIs are only used after fabric filters. Radials and radial tip wheels are still used after cyclones. This looks more like a radial tip. I think its a mistake on HF's part or a QC problem. We are talking about HF, you can't expect 100% QC compliance and Cadillac quality at those prices. I would suspect that the likelyhood of them putting the wrong wheel on the wrong fan is highly possible/probable, but who knows.
Mike