generator rebuild puzzle, and parts interchange...

[esde]

I am in the midst of rebuilding a thin slot generator for my 56 vert
page 6 here: https://www.thesamba.com/vw/forum/viewtopic.php?t=...;start=100
to summarize my issue.. the armature tests good. The field windings appear good, though I have not found a way to check the specific resistance. I have continuity where I'm supposed to and I'm not shorted (far as I can tell)
My completed unit will not spin when I attempt to polarize it, so I am going back through it. My first shot will be to swap a different cleaned and machined armature in. If that fails I will swap in a different set of field windings.. and here is the puzzle.Generally I'm pretty good at electrical work and rebuilding, but this is beyond my understanding, so I'm hoping someone with more knowledge can help I have many 180 watt generators to harvest parts from, but no more 160 watt thin slot generators. Could I use the field winding from a 180 watt unit? Or would I have to use the 180 watt armature also? I appears that the later 180 parts will swap straight in to the early 160 watt housing, but then I suppose I would need to use a later regulator.. and the whole reason I'm rebuilding this is to get the correct period parts on my 56. A quick search through parts numbers only shows one number for the field windings, so I'm just not sure what to do..
Any insight is much appreciated.
SD
_________________
modok wrote:
Bent cranks are silent but gather no moss. I mean, ah, something like that.

[VW_Jimbo]

What tests did you perform on the fields and the armature?

Try this out. These tests were what I was taught.

Link


Have a fire extinguisher close by. I had a generator with bad fields catch on fire one time!

Good luck!
_________________
Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[scottalford]

I'm in the middle of the same restoration with my 56 thin slot generator now in parts on the bench. I took a heap of photos of how the windings go in as I was concerned about putting everything back together.

The two pole shoes are different from each other, are they back in their original positions?

Are the windings wired so that current flows clockwise in one and anti-clockwise in the other to get a north and south pole?
_________________
I hate rust!

1959 driver with original 36er
1959 vert in rustortation http://www.thesamba.com/vw/forum/viewtopic.php?t=525582&highlight=
1954 oval just waiting

[esde]

field coil resistance was the same for both coils, about 1.7-1.8
Armature wasn't shorted to the shaft, but you can't test the individual sections without a growler..
I swapped the armature for a spare and it's changed things.. but doesn't want to spin under power. I need to try with a battery and not off my charger maybe.
Stay tuned.
_________________
modok wrote:
Bent cranks are silent but gather no moss. I mean, ah, something like that.

[esde]

So, the only reason I'm doing this is that I have a dozen later 180 watt 90mm generators, and just two 160 watt thin slot generators. And both of the thin slot generators have had a rough life and need everything..
So let's see if I can rebuild 180watt parts into a thin slot case.
Sometimes these things don't want to come apart. Whatever you do, DO NOT HIT THE SHAFT WITH A HAMMER. Use a puller

compare armatures, 160 to 180

dimensionally they are the same, except the 180w has slightly longer magnets.
The shaft is a little chewed up where one bearing was seized. Hopefully I can clean it up
The 180w field coils appear to be a little longer, but it is like measuring a football inside a bucket. Need to get them removed to really see what's different from the 160w coils.

Brush holders are almost identical

Fan end bearing cap is different, I'll see which seems best and decide

My mega ghetto armature surfacing lathe. This is not found in the machinists handbook.
But hey, any port in a storm right?

I cleaned and revarnished the windings, and will finish cleaning it up after that dries.

Pretty sure this is going to work....
_________________
modok wrote:
Bent cranks are silent but gather no moss. I mean, ah, something like that.

[VW_Jimbo]

Man, dude! A drill press would have been better, but I do enjoy seeing the creativity! I once laid a drill press on its side to turn a set of Queen Anne legs I was creating!

What is the red application stuff? Rebuilding these is not my area of knowledge. Been way too long!
_________________
Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[KTPhil]

Undercut the insulation after turning.

_________________
Current Fleet:
- '71 Fastback
- '69 Westfalia
Retired:
- '67 Beetle
- '65 Beetle (x2)
- '65 Bus
- '71 Squareback

[esde]

[VW_Jimbo]

The hack saw blades works the best. Put an angle on the business end, like a 30 degree angle. Makes it dig in just the right amount!
_________________
Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[esde]

ONWARD:
field coils removed

The pole shoes are the same.
The coil insulation is in good shape so I am leaving it. If I removed it, I could count the windings and take better measurements to see if they differ from the early 160 watt field coils. But it's an abstract shape and hard to measure..
Proof of concept, they fit!

The later case has a step cut end for the bearing cap to sit in, and the bearing cap has a corresponding step. SO early cases get an early rear bearing cap and so on..

more later
SD
_________________
modok wrote:
Bent cranks are silent but gather no moss. I mean, ah, something like that.

[esde]

so I didn't unwrap the field coils, but I did replace the positive and field leads, and then used a ring terminal to secure the hot lead to the brush connection. Normally the brush connection is staked to the case with a peened over stud, I removed it and used a bolt with the original insulating bushings

Put the correct early bearing caps on with new 6202 bearings

Soldered on new flag terminal ends and reinstalled the nicest regulator I have

It testes and polarized well, I'll wait to install it till the winter break..
_________________
modok wrote:
Bent cranks are silent but gather no moss. I mean, ah, something like that.

[scottalford]

Great to hear, and also great to know that we can use the 180w armatures in the thin slot generators.
_________________
I hate rust!

1959 driver with original 36er
1959 vert in rustortation http://www.thesamba.com/vw/forum/viewtopic.php?t=525582&highlight=
1954 oval just waiting