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Growler

Posted: Sun Apr 17, 2011 1:12 pm
by dwire
Some time back, while commenting on a specific slow starter query here on the board, I made mention of a "growler" (yeah, it's a euphemism really, but if you've ever used one, you'd know why they're pretty well exclusively referred to as such) At any rate, after about 5 hours of poking, prodding and digging, I FINALLY FOUND my vintage unit. It's a Blue Point/Snap-On unit from around the 50's if I recall correctly.

Here is a picture of it for your enjoyment. These were a staple in every generator, starter (and later before most shops went under, alternator shops as well) "back in the day." Notice in the lower left corner, I have an old hacksaw blade; that's there for a purpose. It's part of the procedure, believe it or not. At any rate, for 6 and 12 volt systems, these units come in very handy and are far safer, easier to operate and give a more rational, "laymen comprehend-able" result as compared to using a high-pot (high potential) tester - I never recall seeing references to how much insulation break-down, or leakage was considered acceptable in either an armature or field at DELCO-Moraine; not in their test specs, nor the original prints, which include the Bosch branded BMW starters at least all those that came on the /5's such as I've had.

Posted here for you viewing pleasure. I also have a purpose built lathe for truing armature commutators on starters, generators and the like - (or any non-induction motor of similar size for that matter) as one might find on a bike or automobile - if it's of any interest, I'll post pictures of it as well, but it's nothing more or less than what one might expect of a compact antique purpose-built commutator lathe for generator shops in the mid 20th century...

Enjoy... --> Douglas
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Re: Growler

Posted: Sun Apr 17, 2011 9:50 pm
by Chuey
Heck yeah! I'd like to see a pic of the lathe.

Chuey

PS I'm an electrical dunce and don't know what the growler does but it's cool looking.

Re: Growler

Posted: Sun Apr 17, 2011 11:13 pm
by dwire
Chuey wrote:Heck yeah! I'd like to see a pic of the lathe.

Chuey

PS I'm an electrical dunce and don't know what the growler does but it's cool looking.
I guess I did not catch the 110 VAC plug in the shot there. You see the electromagnet in the center? It's really a darn strong one run from wall current. You place an armature in the field, switch the power on and you can test for inter or intra winding shorts/opens and as well, if you have a lot of experience with one of these and the armature(s) in question you test often, the pro's could get a pretty good indication of the amount the armature's windings have degraded (an in accurate hi-pot tester... :-))

The light bulb there is simply an indication that current is flowing through the leads you see laying there - it'll glow brighter or darker depending on the amount of current flow as it is wired in series with the two probes. --> Be ready for the armature to go spinning in the field there if you poke it from opposite sides as it'll run just like any motor when you apply the juice to it. While the real "procedural" use for the test leads is to check each commutator pad to ground for shorts and then as well, to test odd/even commutator pads for shorts between the windings (without drawing a picture, I can think of no better way of describing it...)

The term "growler" - while they make a good deal of 60Hz buzz and hum just plugged in and turned on with no armature lying in them; it comes from the "hacksaw blade test" primarily. After placing an armature in the unit and turning the power on, one would take your old hacksaw blade (or similar steel based thin piece of metal...) lengthwise over the armature's laminations and slowly rotate the armature in the growlers field with one hand (holding the blade in place with the other hand...) A shorted winding's behavior creates a magnetic field that will suck your hacksaw blade over toward the slot (or segmented section of the armature) that's shorted. When it is pulled over there, the buzzing and growling noise made by your hacksaw blade or thin steel strip, will quickly explain why they became known as "growlers..." :-)


My best bet would be to grab a camera with video capability and do one or two of our BMW Bosch starters and maybe a generator and/or alternator or two - the device is pretty simple and intuitive to use, the "little tricks" on how to use one quickly and effectively to get a correct indication of the condition of the part under test, is far, far easier to see than try and explain. Proof in the pudding of this is that several mechanics I knew in my youth that knew how to properly use these units, could not have told you the difference between AC and DC. So it's simply "procedural" in that, while knowing how and why they are a useful tool is interesting and insightful, it is not a prerequisite to properly using one.

I'll snap some shots of my old lathe early next week. I just was out at the storage place and noticed I need to not only find a new belt, as I think mine came up MIA, but also, it would appear the cutter-wheel tool for under-cutting the mica in generators, motors and such has gotten broken. It's not all too high tech; perhaps I could replace it with a hardened "star washer" LOL!

Re: Growler

Posted: Sun Apr 17, 2011 11:42 pm
by Deleted User 287

Re: Growler

Posted: Mon Apr 18, 2011 12:05 am
by dwire
Nice! 'Tis a shame for that fellow to have a pretty nice unit and 1) not show you really what all it can be used for and 2) nor the proper way to use it - other than simply saying "...The blade will vibrate - it doesn't..." Only two tests were performed and of the two, only the test via induction into the armature using a feeler (the hacksaw blade) was done properly... As a matter of fact, when he used the voltmeter on the commutator segments, the lower voltage he was reading (8-9volt I believe he was saying...) would have indicated the same thing the standard feeler test does - that is not at all "really" what the probes are useful for, as with the electromagnet switched on, you should be able to do his "test #2" and if your read the same voltage from consecutive commutator segments as he was doing (reading the induction induced into the armature from the growler itself) if they all read the same, it cannot be shorted nor if they are EXACTLY THE SAME are any of the separate windings broken down - unless they all were... Whatever, "RANT MODE OFF..."

No sweat though, no one here nor anywhere "really" need know how to use one I suppose anyway... Just throw away and buy a new unit or swap your OEM unit out as a core for one already rebuilt; or in the case of our BMW's perhpas a junk Valeo with magnets that come unglued and collide with the armature... :oops:

If that is as good as it gets - no wonder I next to never look at anything on YouTube...

Re: Growler

Posted: Mon Apr 18, 2011 1:04 am
by Deleted User 287
You sure are a grouch, dwire.

Here is a link to all 15 of the guys videos. See if there is one that better represents your attitude expertise.

http://www.youtube.com/user/Mackiebrat#g/u

Re: Growler

Posted: Mon Apr 18, 2011 8:42 am
by dwire
No need for me to "go there" as far as YouTube or that gentleman - and I'm not a grouch.

I often wonder why I bother. Ironically, while you likely had not the attention span to read my post to begin with and I lamented that it would be easier explained and seem less complicated if I recorded a video of a growler's proper use, my explanation in print was far better than that gentleman's video. He also is not using his growler, ONE DESIGNED FOR USE ON AUTOMOTIVE STARTERS, GENERATORS AND THE LIKE on an appropriate test armature. If you can read below, the instructions supplied for an identically designed SNAP ON branded Growler as he is using, you'll see why I said what I did. Step 1-3 with a steel feeler and step 4 are essentially redundant and the instructions indicate this. The armature under test (POT) is suited for a much more complex tester that uses high-freq pulses and a high potential circuit as well to check for the windings' insulation break down accurately; especially since it is a 110VAC motor's armature, which mandates the high-pot test anyway due to legal liabilities.

I try my best to provide such things with good intentions, not to compete with your 1,000+ post count, nor inflate an ego I do not have. I learned how to use these devices for their intended automotive applications from folks far older than your YouTube poster and as well from a handful of old now as well deceased engineers at DELCO (Dayton Engineering Laboratories Company) in Dayton, OH that worked side by side with Mr. Charles Kettering when the practical mass produced electric starter for automotive use was designed and patented around 1911 - if I recall the date correctly. You can Google and Wikipedia their stories - but not mine; so believe what you like. That was my career for a number of years, working in THE DELCO lab, engineering test and then later engineering and then quality control and production engineering...

I'm neither the grouchy dick you take me for, nor the egomaniac some have implied here. I'm not omnipotent, nor perfect and make as many mistakes and errors as the next guy. I just find it troubling for people to post things such as that gentleman did on YouTube in an age where we need to get valuable nearly lost information out there for posterity and then have it less than what it could or should be as was the case for your original hyperlink; for 25,308 people that watched that video have not really learned how to use said device completely and properly - and most who view such things take them as the gospel too...

If I were to publish in the New England Journal of Medicine a procedure that was incorrect, one would expect their colleagues to be quick to correct it, would they not? Let us hope; and sadly it appears more have watched his video than read any medical journal these days; at least the ones still in print...

BTW, sorry I modified this for it to fit here easily - if you want the .pdf for this pretty modern growler from Snap ON, just ask...
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Re: Growler

Posted: Wed Jul 25, 2012 6:14 am
by dwire
Oddly, we can no longer re-edit our posts; bet there was a time limit set, which can be done, or perhaps when the webmistress sorted things out, all of the older topics were locked. So, since I am moving a great deal of data around at my web server at the domain, I'll just put the growler picture back up down here for anyone who has interests. The same will apply to any images embedded in posts here as it would seem there is nothing I can do about it.
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Re: Growler

Posted: Wed Jul 25, 2012 6:21 am
by ME 109
The last band I played in was 'the Grolwers'

Re: Growler

Posted: Wed Jul 25, 2012 6:32 am
by dwire
That's a cool name. My semi-pro/pro act (and like yourself the last 'act' I played in as a performer, before moving to the other side of the glass) was called Heropup - and if you know where that obscure reference came from, I applaud you!

Do like the growlers though - I'd hope to think you were not playing country and Western like the Blues Bros. or something with a name like that... All I can say is on or off stage I wear hearing protection and often enough, be it for content or db, I was most happy to have them available!