Update on the dirt-simple DC voltage reducer

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shows the finished job, in its aluminum box with screw terminals.
It's ready to go to work.
Reply to
Don Foreman
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Don,
Nice looking,
Hey if ya think those MOS-FETS kick ass ya ought to look at the HEX-FETS... awesome stuff, arc welder class!
Yeah those guys up in 'Joe Town' (San Jose) sure put some good smoke in those things, just make sure ya don't let any of it out :-)
--.- Dave
Reply to
Dave August
Yeah, me too. Fine design all around. Typical Foreman. He does this for fun in retirement while a lot of practicing engineers would like to be able to do as well.
Bob Swinney
Reply to
Robert Swinney
Nice job. I like the look of tin-plated brass. Is it hard to do?
Chris
Reply to
Christopher Tidy
I see those transfusions of puppy blood are working out well!
Reply to
Tom Gardner
very nice. would be interesting to see how it works in real life.
i
Reply to
Ignoramus20689
It's quite simple. The hardest part is getting the parts absolutely clean -- and that isn't difficult but it must be done well. Once the part is clean, immerse in plating solution along with a tin anode, supply it with about 10 mA per square inch for maybe half an hour.
There are surely formulas in books for what chemicals to use, but I just buy the stuff from Caswell. His stuff is a bit pricey, but it works very well. They have a distributor in the UK now.
Note: I don't buy the "kits", just chemicals and anodes.
Reply to
Don Foreman
Works fine at the bench with no perceptible temperature rise while driving a motor at 20 amps. The loaded motor got pretty warm, though.
Reply to
Don Foreman
That's interesting. I checked out Caswell's website and you're right that the solutions are a bit pricey. $12 for 8 oz. I'm guessing that's going to be £12 for 8 oz here in the UK. I might just stick with de-rusting for the moment. I definitely have a lot more use for it, although the tin plating looks cool. I should have my de-rusting power supply up and running soon. I'll post some pictures when I do.
By the way, what is that "wand bandage" shown on Caswell's website for?
Chris
Reply to
Christopher Tidy
That's for "brush plating". You wrap a bandage around a piece of anode metal, as tin if you're plating tin, then soak the bandage in the electrolyte, connect the power supply to the work and the anode, and "brush" on the plating with the resulting "wand". At least one of the brush plating solutions (gold) relies on metal already in the solution so the anode can be stainless or something.
Reply to
Don Foreman
I have a lot of advantages over practicing engineers:
*no schedule *no beancounters wanting me to shave another penny *no concerns about producability *no marketing guys telling me there's no market (I don't care) *the machinist, welder and elex tech all work for free and don't argue with me or bitch at me *no boss wanting more faster cheaper *no meetings or vugraphs -- ever *no purchasing dept making me use crap from "preferred vendors" *no safety twit telling me what he thinks I can and can't do safely *no lawyer demanding that everything be idiot proof *I don't have to ever finish a project *I don't even have to start a project I don't want to *I can't be fired for screwing something up. I'm already unemployed.
It's a wonder practicing engineers ever get anything done!
Reply to
Don Foreman
Huh?
Reply to
Don Foreman
Okay. That makes sense. I think I recall someone talking about using some form of "brush de-rusting" now.
Chris
Reply to
Christopher Tidy
BTW, Chris, I don't know if those terms "bandage" and "wand" are general use or whether Mike Caswell coined them. Mike is an expat Brit, by the way. He grew up in Calne (Wiltshire).
Reply to
Don Foreman
Both are in pretty common use - "bandage" as a dressing for a wound and "wand" as in "magician's wand". I thought these were used in the States too. I don't know if Mike was the first to use the terms for electroplating. I haven't heard them used in that sense before.
All I know about Calne is that there's a well-known girls' public school there. I don't remember ever having been to Calne.
Chris
Reply to
Christopher Tidy
IMHO
You left out the best one, Don....
You get to sleep with "the boss" every night....
Jeff
P.S. I wunner if the guy behind this company is also a retired "slip stick" generation engineer.....
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I've got a feeling that "What happens in Vegas is going to stay in Vegas". I'm dubious about how much sales appeal those "drill powered" gadgets will have.
OTOH I bought and have kept for maybe 30 years a little plastic cased rubber vaned pump, intended to be used to suck engine out through the dipstick hole, or do other fluid transfers. (But not gasoline, not many drills utilize explosion proof designs. )
It seemed like a good idea at the time I bought it, but to the best of my recollection I've never ever used it.
Jeff
Reply to
Jeff Wisnia
According to Don Foreman :
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Well now -- isn't *this* a meeting? And your web pages are the vugraphs? :-)
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A serious benefit.
Another.
And the best one. :-)
Agreed.
Enjoy, DoN.
Reply to
DoN. Nichols
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Hmm ... I don't see anything which will keep the drill from rotating -- other than a little gravity assist working on the battery pack. Perhaps there is some kind of anti-rotation support on the far side of the drill motor -- with provisions for getting the cable up to the trigger to turn the thing on and off.
:-)
Hmm ... that sort of sounds tempting with the car which we have, a 4WD SUV with a heavy duty steel skid plate on the bottom which has to be removed to drain the oil. (But I suspect that it has to be removed to change the oil filter anyway. :-)
Enjoy, DoN.
Reply to
DoN. Nichols
Sorry. In the shop, when someone has gone above and beyond to do a good job, we say they have puppy blood; implying high energy and gusto! I most certainly meant a compliment of the highest order.
Reply to
Tom Gardner
Wag wag!
Reply to
Don Foreman

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