Hi all,
Since it's cold and soon to be nasty here one of my projects is to get my generator working better. Sometimes it's fine.. other times not so much. Is there a way to bench test it out of the car?
Bob ; I have a lot of pleasure of this one .
Toon
Bob
It is best to dynamically test the generator. You need some way to connect a battery with cutout and spin it just like in the car, Here are photos of a Allen Electric Model T generator tester and a home made unit I built with some additional features like Toon's.
Also here is a photo of a modified generator drive gear to interface the motor shaft with the generator drive gear to spin it.
If you would like a wiring diagram for this type of tester send me an email.
Ron the Coilman
It's not pretty but you can clamp the generator in a large vise, slip a hose over the gear and clamp it and then slip a socket into the other end of the hose and again clamp it. With the proper adapters you can power the generator with a good hand drill.
Donald C,
That sounds like the way I usually do things. That and a rigged up ammeter with voltage measured with a common multimeter. There is nothing wrong with that. Don't argue with success!
Drive carefully, and enjoy the holidays! W2
Donald & Wayne
Certainly those solutions work, but when you deal with many rebuilt generators being able to move quickly is important.
In my case, if you need a tool and don't buy it soon you will find you paid for it and do not have it.
Ron the Coilman
Ron - Henry was right! One of my favorite quotes.
Ron - Those armatures are beautiful, do you rewind those yourself?
Mike
Actually that quote is attributed to William Pioch, HF's genius machine tool designer.
I do not rewind my own generator armatures. After a long search, I found a shop in the Chicago area that does excellent work. It is expensive, they are experts and the service is great. If I call the owner with a problem, he listens and it is resolved immediately.
Great people to work with.
Ron the Coilman
are these new armatures hand wound or machine wound? its my understanding the T armature is different from most and thats why nobody will rewind them?
just curious.
Matt
You are over simplifying the rebuilding of 80+ year old armatures. The Model T armature is nothing special to a competent rebuilder.
The armature must be completely disassembled and each part tested for the possibility of reuse. New parts are not available! I get a 60% yield from used armatures I send the rebuilder. Rewinding is done by hand because of the low volume. They make and use new armature shafts if required. Reassembly, refinishing usable commutators, balancing and test are part of the process.
It's expensive.
Ron the Coilman
I was just told the commutator had a different number of segments or somthing, i recently bought a rewound armature that im having problems with, i noticed the commutator hadnt been turned, just sanded. long story short, it needs to be turned.
its incredible the amount of specialty work that goes into the armature, just the commutator alone has got to be quite an involved endeavor.
Rewinding is time consuming but the hardest part is keeping track of the leads.
You have to watch turning the commutator. Not only does the diameter decrease but also the segment width. And the thickness of the segments is deceiving. They are actually paired pieces keyed together to form the 21 segments. (42 pieces.) The rear view you see above shows what looks like thick segments but the actual brush contact area is less than half of what you see.
Matt
There are not many armature repair shops left in America.
To my knowledge no one makes replacement commutators for Model T generators.
Commutators are normally removed to burn-clean the shaft and lamination.
Used commutators commonly have inter bar shorts, the Mica burned out, or as Ken points out have been turned many times making them too small to use. Reusable commutators are turned, undercut, chamfered and finished using an armature lathe.
The armature shaft is commonly badly worn or bent and the rebuilder I use makes and installs new shafts if required.
Most small shops I've seen rewind by hand using a fixture to to hold and rotate the armature. A larger fixture was made to feed the wire and rotate the armature to speed up the process, but I have only seen photos of them and never seen one actually in use.
Like Ken stated a "time consuming" process requiring some special tools.
Hope this helps.
Ron the Coilman
What all does the armature lathe do? I suppose it undercuts the mica?
I find all this electric motor stuff facinating, ive always been a purely mechanical guy, but now im getting really interested in the electronics of the T, I dont currently have a mag or coils on my T but i hope to have them soon, then i want to make an HCCT.
Matt
It allows you to fotate the armature shaft on centers via the motor and belt for commutator cutting and finishing.
Using the motorized cutter mounted and movable at right angles to the commutator you can undercut the mica between the commutator segments.
It is hard to see the cutting saw in this photo, but look close and you can see the features.
Gary Tillstrom has a package of diagrams for making a HCCT.
Have fun.
Ron the Coilman
Yeah i think it was Gary Tillstroms post i saw on how to make one, looks interesting and fun. and being OCD i know ill be testing and adjusting my coils more often than i need too...lol. I mean shouldnt everyone have an HCCT?
That armature lathe is pretty cool, eventually i hope to have a rod lathe for machining babbitt. doing bearings is what i aspire to do.
When I was restoring Splitdorf generators I'd cut the commutator on my 12" Atlas lathe, just a skim cut to clean it up, usually no more than .010". Then I'd undercut the mica on this undercutting machine. Having the right tool for the job makes things so much easier.
Having the right equipment is always wonderful! (Anyone need wire/cable testing or fault locating done?) But understanding what needs to be accomplished plus some creativity can do a lot with a little.
I love seeing photos of the right setups for doing repairs correctly.
It is time for me to say it again.
Thank you, Ron, for sharing your vast knowledge with us. The model T hobby owes you a lot!
Drive carefully, and enjoy the holidays! W2
Thanks to everyone!! My local guy can check them out but probably not fix them. He is an antique car guy ( chevy's) So I'll probably send it off to Ron if is bad.
There is a difference between getting it "fixed" and sending it to Ron.
The local guy is a shop with 2 gentleman + staff who repair generators and alternators for a living. They do an awesome job, and one of them has experience with Model T parts.
If they cannot fix it, they will tell you. They will not try to do something just to get your business. Excellent old time honesty. Highly recommended.
As Dave pointed out and I incorrectly put the "Chevy" word in these guys are pretty good. They did the generators for my old jumper pack and do a great job on my plow motors. A lot less $$ than buying new ones ;)
Test
Doug
I learned long ago "fixing" Model T generator or starter is a no win proposition. They are 80+ years old, most of them have 16 things getting ready to fail, and if you "fix' today's problem you will own it forever.
I will be the first to admit my rebuilt Model T generators and starters are very expensive, but they are rebuilt from the ground up with no shortcuts. They are fully tested to meet original Ford Specifications and guaranteed for one year.
Ron the Coilman
Generator Testor
Generator Testor
Generator Testor
Generator testor 2
Generator Drill on top
Generator Drill on top
Generator Drill
Generator Governor on top of pile to the left. You can see the part sticking out that controls the carburetor.