Ever wonder why your wiper blades wear funny?
What if your WFE is untrue?
Next trick presumably involves a lathe and a hammer…
I’ll let y’all know how that WFE beating goes.
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And a midget, 2 golf balls, a garden hose…
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I’m no rocket surgeon but to me it looks like (at least in the first video) they placed the Center pivot point in the wrong place. Take the whole part off, fill in the hole, find the true Center and then drill a hole there.
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I’m pretty descent at rocket appliances. To know for sure what is out of whack first thing I’d be doing is chucking the whole works up in a lathe with a dial test indicator (DTI), from the drive shaft that connects to the motor. Make sure shaft is true next to the chuck, then see how far out of true the bearing plate that suspends it is (guessing this will be fairly close)
Next move on to the edges of the top of the wiper frame. You’ll probably have to measure using a drop indicator (not lever) and lift it between the gap sections or else it’ll knock the DTI and throw your readings off. I’m going to take a wild guess its out a bit at the top and out a whole lot more at the bottom of the wiper frame. Whether this is due to the shaft being dropped on the threads or poorly cut threads, who knows.
If the pivot/bearing is relatively true I’d pull it off and chuck the shaft, figure out where the bend is in the shaft and CAREFULLY use the lathe carriage to hold pressure against the far end while SLOWLY using an OA torch to flame straighten the shaft. You can use the DTI on a mag base on the carriage to measure deflection away when it starts to cool and retract in the opposite direction.
One of Tom Lipton’s books has an excellent section on flame shaft straightening (which is not intuitive or quick to do and takes patience), can’t remember if it was Metalworking Sink or Swim or if it was Metalworking doing it better and I’m nowhere near home to check my library and tell you for the next couple of weeks.
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Have had a wiper that was running like this before. Best I could figure out was that dickheads repeatedly trying to bump the wiper when it was jammed over time caused it to twist/deform
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Nah, it may look that way in the video, but that doesn’t appear to be its major malfunction once you get the cage on the bench.
@greenbuggy thank you once again!
always look forward to your responses.
This time I’m just gonna hand it off to a trusted machinist.
If we decide to chuck the wiper body up on the 24” lathe I’ll be back with pictures/video 
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I’ve fixed exactly this twice.
Slap some zip ties on the frame to use as static reference points, rotate the assembly and find your highs and lows, and gently bend where the shaft meets the blade holders back to true. Its possible to pop those welds if you’re too gorilla on it.
I rebuild my bike wheels exactly like this, too. Zip ties and squints.
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Remove wheel from bike, inflate tire. Find right spot to hold it. Smack it soundly against the playa…
Bike repair as performance art can be fun.
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Properly applied percussive maintenance is an art in itself
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That’s why I always bring my trusty calibration hammer!
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My dad always told me “if you cant fix it with a hammer youve got an electrical problem”
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would that ever be relevant on a wiper?
the cema instrument I’m currently smacking my head against (percussive maintenance?) has a vfd on the roughing pump and that struck me as bizarre when I first figured out the wiring, and still doesn’t seem useful for distilling cannabinoids…
not sucking so hard can also be accomplished with a vacuum controller or a controlled leak.
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It’s rarely relevant unless there’s excessive solvent left in the crude or your using the wiper for solvent stripping. When distilling cannabinoids the pumps are usually running at 60hz.
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So I could see the VFD being used for devol, but I’ve been cooking something up that I’ll share when it’s done/actually works. I’m gonna pull heavy vac on my feed vessel and spray my crude in at high temperature to encourage any solvent left by the roto to come off through a diaphragm vac instead of bumping in the evaporator. Basically a redneck spray dryer for less than 100$ in parts.
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Thanks.
thats where I was, just from typing out the question…
chances are I should check see where the VFD has been told to stop responding to “more!”, because the “as run” SOP looks to have involved turning it to 11 every time, and the display attached to that potentiometer says something foreboding like 460…pump sounds and behaves ok. pulls system down to pump blank off, which looks to be about 30um. that’s without changing the oil.
still wanna know what it’s being told to do 
I’m convinced!
another dial/lever on the process is almost always a win once you figure out which way/by how much to twiddle the thing to get where you need to be.
I think it would be cool as shit to throttle my vac. Well technically my new dry scroll can throttle from 30hz at full chooch to 20hz at 70% minimum speed. Last I tested it went from 80 micron (without diff pump) to 500 micron at 70%. Kinda wished it went slower but it seems that Edwards might have done some testing to determine what minimum speed should be 
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well shit, if Edwards is sending them out the door that way…
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I’m fucking tickled with mine. I got it on a steal and it is scary quiet. Like it sounds like some alien shit. I believe @thesk8nmidget said y’all had one. Really been impressed so far!
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Has anyone tried spraying their mostly solvent recovered crude into the feed flask? My thoughts was to have it under high vac and somewhere around 100-130C. I would then have either a funnel with a valve or a gear pump to inject it into the feed flask with one of those spiral stainless atomizers. My thoughts were that we might not have to be as anal about solvent recovery on our tiny roto if we could remove the rest of it by “spray drying” it into our feed flask. Thoughts? I’ve got all the parts to do it, hopefully plan on trying it out next week!
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If you pre-heat the feed and shoot it at high pressure through a nozzle into your vessel that’s under vacuum, that sounds like a flash evaporator to me.
I think that is is probably the most correct type of system to have between primary solvent recovery and distillation. Done right it should have no problem handling decarb, desolventizeing, and de-terp. Maybe even heads removal if you do it right.
We haven’t got around to building one yet, but it’s on the to-do list.
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