Homemade Record Cleaning Machine

[ozmoid]

Damn it man, it's not suction, is it? I'm confused. Do I need this thing to suck or not?

Yes, you want your RCM to suck.

(OK, now the boss wants to know what's so funny... Back to work!)

 

[macaltec]

Find a good woman. :stupid:













I really, really, could not help myself.

I knew when I posed the question that this is where the conversation would end up, in the gutter.

 

[ByrdWyngs]

Hate to disagree with the experts but a 1/2" pipe with a small slot just can't move enough air to generate much of a vaccuum. Not only is the size a limitation in terms of volume of air, the disruption caused by friction effects is proportionally larger relative to airflow and has large effects on air velocity.

Empirical evidence would tend to disprove your theory. Relatively small diameter wands (and low volume pumps) seem to work just fine on VPI and other commercial RCMs. As long as the gap between the wand and record surface is relatively small you shouldn't really need to move all that large a volume of air. The important thing I would think is to keep the air velocity relatively high, and that can be accomplished with a low volume and small gap as effectively as with a high volume and large gap.

 

[absolon]

That might indeed be the case.

My experience has not agreed with that and what I was taught about hydraulics does back my contention that friction in a small pipe has proportionally larger effects on fluid velocity than in a large one.

On the other hand, I've not bothered trying to optimize tube size and pump capacity beyond my initial experiments with 1/2" tube and the hose that came with the vaccuum I use. The smaller tube didn't work worth beans and the large one did thus satisfying my requirement and ending my experiment.

 

[Tedrick]

I've a question for the various builders of the DIY RCM's that are featured in this thread. Concerning the vacuum motor each selected for their project, each appears to me to be unsealed. Is there not danger of electrical shock or even fire/explosion hazard (from alcohol vapors) if liquid (or vapor in the case of alcohol) were to get inside the motor housing? I'm guessing that the alcohol concentration is probably low enough to not be a danger, but what about the water? Does the water evaporate so quickly that it's not an issue?