Bridgeport Power Feed 6f Motor Mount Question

If you are changing the resistors that I’m thinking about? Then they went bad/smoked because your forward-reverse switches are bad. You will need two new micro switches. Don’t bother trying to clean them, BER, just buy new ones. And the trimers on the board only get turned when you tune the board to the motor, after that, they are torque sealed. And it really doesn’t mean that much in your end result of the whole shebang working. If you think that was the problem with the feed not working, it was not. And I’m not saying it wasn’t a problem, just not the one that killed your Power Feed.

Two new switches ordered. If I'm lucky I'll get to do some testing this week once parts get in.

There were 4 resistors that were waaay out of tolerance. The bad ones were rated at 18k, 27k, 300k and 2.7 million.

I hope you guys are going to help me rebuild the top end. It's quite noisy.
 
Nope, it was not any of those resistors. Good Job.
Well the bad ones are coming out. I went through every single one on the board by de-soldering one leg on each. Making sure that I put a sharpie "dot" next to
each as I tested them. The resistors that were bad I bent the leg over that I had de-soldered which should make quick work when I get the replacements.

This board, control panel, and switch setup should be in fantastic shape once I'm done learning! :)
 
Most of the components on that board are not value sensitive. What I mean is, if the reading you get is out of tolerance to the posted value on the component, then chances are it’s OK. You should be looking for something that is dead, no longer any good and not just out of tolerance. I would not de-solder all those resistors and other things. All those 1/2 watt resistors are the last thing on the planet that would fail on that board. What is more likely to happen is damage to the copper circuit paths from all the de-soldering. Good Luck…Dave
 
Hey Dave, I was lucky and very careful about de-soldering I tinned and cleaned the tip of the iron every time. So no excessive heat or lingering if it didn't flow right away. I won't de-solder almost everything next time. But it's hard for me to not get excited and jump right in.

I came home today to find all my electronic goodies! It's like second Christmas! The only thing I'm disappointed in is the pot. The shaft is way too long. I'll have to dremel it to length. So I've got my new caps, switches, pot, and resistors. Hopefully I can do some dry runs...sans gearbox this weekend or perhaps tomorrow. I am thoroughly jazzed about all the parts.
 
OK, on the motor direction switches are they adjusted to their "neutral" position? This being when the direction control handle is in neutral position.

I assume this is correct? So that the any contacts marked "NC" are closed and the "NO"s are open?
 
Does anyone have an expanded diagram of the boehm 4640. Apparently I've got "spring" type disk and flat washer that go in some position on the non-output end of the shaft (I think) under the spring clip. I've forgotten how they go back in.

Yesterday after putting this back together and hand spinning the motor it would go in one direction but spinning backwards would cause it to catch and drag on something. I assume it was an electrical line. Or perhaps the missing spring washer. So I'm going to put the spring washer in between the two flat washers I think it fits between and put it back in. If It binds up again I'm at a loss since the output side bearing was replace. It's possible that I'm not getting the armature lined up on the bearings properly? Guess I will try again tomorrow.
Paul
 
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Hey Paul - don't know if you got by the preload washer issues or not - see below for what mine looked like on the output end

Motor%20Preload_zpspjzhpugt.jpg

Maybe you can help with an issue I am having regarding orientation of the clutch shaft - see next post

Thanks
Rick
 
So I've been pretty distracted with a variety of things going on and this is the first chance I have had to get back to this power feed. I've got the majority of the main housing re-assembled but have a question on the orientation of the clutch shaft. The clutch shaft has a woodruff key slot for the handle that I believe faces the back of the unit (assuming the access door with the sight glass is the front). This results in the drive pin hole on the clutch shaft facing the front to back. Also - at the other end - the narrow ridge faces front (this is the switch actuation end of the clutch shaft). I believe the cam detent faces the front and the large "V" that rides on the clutch arm detent roller faces right. Here's a few pictures of how I think the clutch shaft is assembled. I'm hoping someone can confirm this.

Top (handle) end
PICT0001_zpsrlim3cal.jpg

Bottom (switch actuation end)
PICT0002_zps9wduqgbg.jpg

Thanks
Rick
 
Hey Rick, That's exactly how mine is assembled.

I've got mine assembled up to being able to test the wiring. The motor is detached from the gear housing. However, the Motor is still acting up and blowing fuses. I did get the motor to spin up but once moving the speed control wouldn't slow it down or change it's speed. Then blown fuse. I'm getting close to sending this in to someone that can handle the board and trouble shoot it and the wiring. I can't see that I'm any closer than I was when I started. :(


Paul
 
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