Can someone explain to me how the fine feed attaches on M head?

[azscooby]

I bought an M head Bridgeport (just the head) and plan to attach it to my USMT mill. It’s all up and running now with one exception.

The head came with a fine feed handwheel but when I push it on it just spins without engaging the end of worm shaft. It also can’t spin/rotate as it hits the casting above the micrometer.

I have scoured the interwebs for a picture without any luck.

So right now I have the fine feed shaft coming out with the slot in it and I have a handwheel that is an aluminum wheel with a steel bushing insert. Looking at these two parts you’d assume they interact exactlyhow I’ve explained, spinning freely without any engagement.

I’ve got to be missing something, literally.
Can someone post pictures of these parts? From the Bridgeport PDF manual and parts diagram I’d be talking about the engagement of parts #91 and #94. How do these engage each other? I’m guessing there’s some sort of pin crossing through the handwheel that locks into the slot.

Thanks in advance.

 

[azscooby]

I also have another M head on it’s way that is missing the entire fine feed assembly. If anyone has these parts (circled above) please let me know.
Thanks again.

 

[benmychree]

Does tightening #34 do it? I had one, but its been way too many years ago to remember for sure. I do remember that I hardly ever used the fine feed, if at all, I don't think I even had a handwheel,

 

[Technical Ted]

Yes, tightening #34 will engage the hand wheel feed. From the picture, the hand wheel you have it not the original. If it fits on the shaft, you can use it, but you will need a cross pin that fits into that slot so it will turn the feed shaft (#91). If it goes on too far, you'll need to make a spacer to hold it way.

I didn't have the original hand wheel from my M head. I modified one I had to work. I just had to open the bore to the correct size and install a cross pin and it worked fine.

Ted

 

[azscooby]

Ok, that’s what I thought, but I had seen other M heads with similar handwheels.
Tightening #34 engages the fine down feed, that part works fine (I understand how that’s supposed to work.) It’s just attaching the handwheel so that it actually turns the worm gear shaft.

if someone can still post pics that’d be great, I’d like to see how it’s supposed to work.

I could make a longer shaft to attach to the handwheel so that there no interference (kicking it out from the casting maybe 1/2”) I’m not worried about that, I just wanted to see how it’s supposed to engage.

 

[Technical Ted]

You need a cross pin to fit the slots. Here's some pictures as you requested.

I bored out the hand wheel I had. Made an insert with said cross pin (a roll pin). Installed the insert by pinning it.

It works great. I don't use it anymore, because my M head is sitting on the shelf right now. I've got two other Bridgeport and clone mills so don't use this head any more much.

Ted

 

[azscooby]

Ted, thanks!

that’s exactly what I was looking for!