Ya' all can pray for me!!!
- Thread starter Tomc938
- Start date
Prolly grade 8. Hardness isn't as important as unbreakable.
If you want to learn a lot more about that pin, read this thread, but read it to the end for a strange unexpected twist...... A very important twist!
Collet questions
My old mill used MT3 style taper, and most of the time I simply left a ER type collet installed and populated the inserts as require, once in a while I would swap out the ER collet for something else, and removing typically required a reasonably good smack with a brass hammer to get the two...
Will do!Prolly grade 8. Hardness isn't as important as unbreakable.
If you want to learn a lot more about that pin, read this thread, but read it to the end for a strange unexpected twist...... A very important twist!
Collet questions
My old mill used MT3 style taper, and most of the time I simply left a ER type collet installed and populated the inserts as require, once in a while I would swap out the ER collet for something else, and removing typically required a reasonably good smack with a brass hammer to get the two...canadianhobbymetalworkers.com
And I see that 3/8" x 24 is the normal fine thread. He was saying he could only get it from South Carolina. Maybe he meant the OEM part.
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140mower
Don
Pfffft.... excuses.
The OEM is a hex screw with a rectangular nub. Like @Susquatch did for his replacement. It's much stronger.
I might thread a matching hole in a piece of bar stock and mount it in my QCTP. If I work it out right, I should have enough adjustment to cut the nub with an end mill in the chuck.
Now that I know it's an ordinary thread, it's worth a try or two or three.
Do you know yet, if yours is supposed to be a double screw? Ie originally shipped with an alignment screw and a keeper?
Pfffft.... excuses.
You up yet buddy?
Don't forget I have to shovel snow to get to the barn this morning, with a spatula, both ways, up hill!
Pretty sure I can help with the two screws, the cap is another matter. Could you maybe use three screws? The third only serving as a dust cap on the non-rotating quill body.
If you can give me lengths, I'm pretty sure I can set you up nicely.
Thanks for the offer! Very generous. In the other thread I mentioned I'm going to just try the dog point on the screw. My shearing forces will be minuscule compared to what the mill can actually do. So I can use my lathe to do that.
I have the jam screw. It wasn't damaged. As far as the cap, I might just have to blast crud out with compressed air if it gets junk in it. Keeping the quill choked up short will not expose it to anything, so I'm thinking it will be OK.
And with postage what it is nowadays, I can buy the screw locally, have a beer and burger and still be ahead!
Might turn out to be your best bet. Toast my old age while your at it!
I managed to find the spatula and cleared a path to the barn.
Turns out my own Bridgeport
Screw is a 6mm-0.8 screw. Not at all what I remembered or expected. I REALLY HATE what time has done to my memory! And who would have thought a Bridgeport would have metric screws in it!
I do have 3/8-24 set screws 3/8 long though, so I could make you one if your efforts don't pan out. You know how to reach me! Be my pleasure.
Postage on that is only a buck forty or so. I know cuz I just sent @140mower a left handed paper clip betting he doesn't have any left handed ones yet.....
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Was it red?
Please keep us posted about how this goes Tom. Seems to be a lot more to know about that alignment pin than I'd have ever guessed.
I was surprised to hear yours had the rectangular section. I thought that was my idea. Then there is all the debate about function. I think @PeterT pretty much nailed the coffin shut on that one, but some aspects are still an open question. Then there is the size differences. It's a real dogs breakfast!
140mower
Don
Be careful, this "key" is becoming much like the meaning of life...... Some things you might want leave a little bit of mystery.......
Imagine the disappointment when it is discovered that we're born, some crap happens in the middle and then we die....... Our main purpose being to fertilize the soil for the next organisms...... Won't that ruffle a few feathers....
Imagine the disappointment when it is discovered that we're born, some crap happens in the middle and then we die....... Our main purpose being to fertilize the soil for the next organisms...... Won't that ruffle a few feathers....
Was that from your BP or your Hartford?
I thought at the time I was sorting out my (metric) First that it would be imperial like a BP because some other things were so I was surprised the set screw was metric.
The First is an eclectic mixed bag, it even has some imperial fasteners with metric heads!
D
Be careful, this "key" is becoming much like the meaning of life...... Some things you might want leave a little bit of mystery.......
Imagine the disappointment when it is discovered that we're born, some crap happens in the middle and then we die....... Our main purpose being to fertilize the soil for the next organisms...... Won't that ruffle a few feathers....
NOMINATION: Don for forum philosopher!
D
The screw in the photo and the one I measured were both bought at H&W from the parts list for a Bridgeport Varidrive. I replaced the pin in the Bridgeport (which had sheared off) before I sold it.
Worrying about this was kind of the straw that broke the camel's back and caused me to make a new stronger one with a rectangular dog point for the Hartford. But I wouldn't have started with a Bridgeport Pin because then it would have been too short. So I assume I used one from my set screw stock. It very well could be a different size. But I don't trust my memory to say one way or the other.
If it becomes important to anyone for whatever reason, I'll take it apart and find out.
I think your memory is better than you give it credit for!
Ummm…. I’m not sure how to put this so I’ll just jump into it: being a person of some curiosity I did a bit of surfing and I bumped into an article on the H&W site where they talk about replacing the screws, they mention that the BP set screw pair are 1/4-32…..which is darn close to M6.35 x 0.8p.
I also see a few ads for BP “collet alignment screws” and I saw something I hadn’t noticed before, some, not all, have the square end. No wonder they’re easier to set the locking screw compared to my First, you can make a tool or use a collet to keep it from turning when you set the second screw.
Always something new to learn.
D
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