Frankenstein Table feed.

Just to keep it short if you don't want to read the stuff below, Which kind of bridgeport power feed handle do you prefer? The Pin engagement type or the twist to engage type? I have only used the pin type and have no idea.



I have a Series II special. Made about 1986. By all signs it never had much use before I bought it. However, the engagement of the handle on the X axis drive motor never worked well. It slips out easily.

I say Frankenstein because according to the diagrams for an 8F or 6F It should have a twist to engage handle. It has the faceplate nose of a 6F-c or 8F. However it has a non twist to engage handle (late model with black counterweight like an 8F), and it looks like it has a dial holder (internal part) of a 6A-B that uses a pin engagement on the handle.

The handle has a pin for engagement, but it and the dial holder are buggered and lets it slip.

looks like I will need to replace the dial holder at least, but I could upgrade the parts to a twist to engage with no trouble.

looking at the top of the casting, there is no nameplate and the holes match a 6F casting. Since it has a protruding nose on the front plate, it is most probably a 6F-c.

click on images to enlarge


6F-A handle assembly



6F-C handle assembly



8F handle assembly

Then there is this: The control lever is splined with a clamping screw, just like a 8F.

weird.

Without pictures, it is difficult to say anything with certainty. Yet if your dial holder has 2 indents for the pin in the handle, then you need the 6F handle.

With it slipping, I see alot of customers putting the spring between the nut and the handle to always have it pushed over. I have even seen guys put multiple washers at the end to put even more tension on the spring to keep the handle in place.

Pictures would help though. Alot.

Jon
H&W Machine Repair

Thanks, Jon. I went out and made some pics. The reason that I finally decided to look at the handle slipping is I did a big goof and lowered the table without getting a small roll away far enough out of the way of the control lever of the feed drive. It snapped it in half. I took the gearing apart to inspect the shaft and it is one tough baby. No damage to spines or shaft bent. For now, I'll just aluminum braze it in the next couple of days. It got me thinking about the crank handle while I was there.

So, as you can see in the pics, the dial holder is rolled out and worn where the pin fits in it. My pappy would call it 'wallered' out. I took the pin out of the handle so it is not in the pics. It is rather peened and rolled at the end too.

The spring is in the right place, and the bronze bushing is correct sized for the handle.

So you see, it is a hybrid of some sort that I cannot find any info on the net. Maybe it came from the factory that way, or some machinist liked the 6F-A arrangement and retrofitted. But seeing as the handle is NOT a twist to lock/unlock, I have my doubts.

click on thumbnails to enlarge

A couple more pics including the results of my inattention of the handle.

motor plate


bottom side


top side

damaged pin end




handle showing no twist release


handle pin hole

It seems to me that the twist release handle is a more robust lockup than this.

I mean that looks like normal wear that I have seen on alot of feeds. This is standard of alot of the C models, where they were just a jumbled mess of different parts from the 6F and 8F.

The design of that style handle isnt my favorite, as you have to have more tension on pushing it into the notch than I think you should. Shy of modifying both the dial holder and the pin, i would just move the spring to the other side. Option B would be replace the dial holder and handle with the 8F version, but I not many people want to deal with that sort of money.

Jon

Thanks, Jon.

I took a smooth straight safe side file to the dial holder and straightened out the cutout. it turned out good. I then used a HSS drill bit of the right size and made a new pin out of it with a flat side, about .15" longer than the old one so it would sit fully in the notch. Works like a charm, now.