One way to shorten a bolt.

[KeithB]

I was working on a project (that I will post here shortly) and ended up needing some 1-1/2" long 1/2-13 socket head cap screws. Unfortunately I had purchased some that were 2" long. Would have swapped them for the right ones but it was late and the vendor I deal with was closed so I decided to shorten the ones I had.

I found a nut and used the upright band saw to cut through one side. Then I threaded the nut onto the cap screw until the bottom of the nut was 1/8" shorter than the desired length, in this case 1-3/8" from the bottom of the head to the bottom of the nut. This lets me measure from the bottom of the nut to the end of the cap screw to get 1-1/2" length.

Be sure you make sure the split in the nut is between the jaws so that jaw pressure closes the nut up tightly onto the screw. The photos below show (1) the unaltered screw ready to be cut, (2) the screw being cut in several light passes, and (3) the finished screw after being cut to length and chamfered to clean up the end threads.

 

[KHornet]

Looks pretty slick Kieth!

Paul

 

[Ian]

Sure beats a hack saw or cut-off tool and file.

 

[Brad]

Would work to hold a bolt to add a brass tip or modify that shape of the tip too.
Excellent idea. Make a single split nut for a thread and keep it in the tool chest.

 

[smokeywolf]

Used to keep miscellaneous size spacers/bushings on hand that I'd threaded and split for this kind of thing. Don't think I've ever used this little trick; it's a good one. Great example of just one of the tricks that you don't see in the books.

 

[Brad]

I drilled and tapped a hunk of aluminum to 7/8-14- I left one end solid then cuts 4 slits 1/2 way down the threaded portion.
When I make a new 7/8-14 die I do most of the work then part it off. I use the collet I made to hold the part in the 3 jaw while I clean up the end where it was parted off.

 

[KeithB]

Well, one of the reasons for adding this new subforum was to spark ideas among the members. I think it's working!

 

[Brad]

If my lathe has taught me anything it is the fact there are far more than one way to skin a cat.
Making do with what one has and being creative are of extreme value in machine work.

 

[Intheshop]

Yup,works great.You end up at some point thinking tooling costs.For instance,cutting bolts with a bandsaw.....it doesn't hit home fully 'till you start buying blades(we make ours from coil stock).Which is more cost effective on a pce of "mystery metal"?A 100+ inch BS blade....a portaband blade...cutoff wheel...you get the idea.


This is where lathes come "back" into focus,their role in keeping operating costs down.You haven't felt pain until some numbskull try's to cut a pce of hardened steel or torch slag with a BRAND new BS blade....doh.(edit,break in BS blades on aluminum,read up on it).

Nice OP post.

 

[fiver]

cheaters.

 

[KeithB]

cheaters.

Darn right!

 

[Intheshop]

Cheating?.....only if you get caught!

Both my lathes got taper attachments....never use them.Hook up a dial gage and run it on the crossslide against a pattern.Same principle works on stock dupe work.

The taper attachment on our '47 Wade 8A is worth more than I paid for the whole lathe.....kinda like a Colt Python box.Which blows me away?

 

[Ian]

That's a helluva way to cut NPT threads....

 

[Intheshop]

We "cut" to .001's...

We grind to .0001's...

Be it metal,composites,or wood.

Concerning the latter.I love it when a wood wacker gets his hackles up about how WW'ing isn't/can't/shouldn't be expected to be the metrology equal to metal.BS....

Take a piano "finish"...might be a rifle stock,and leave an 80 g "scratch" when the rest of it is polished out.Can you see it?Well,that's "tenths" (.0001's).

 

[KeithB]

I never got a taper attachment for manual lathe. Now that I have a CNC lathe I don't need one!

 

[Intheshop]

Keith,have you ever really looked at one?They're pretty...doo-da.I just never saw,even considering the time periods....where they made much sense?I mean sure,they work but,the forces involved...at least typical lathe versions...kinda crude.Prolly just me being "me"?

 

[KeithB]

W/o CNC I would cut most straight tapers using the compound. For long, gradual tapers or for cutting tapered threads a taper attachment is handy. With CNC you just start at one diameter and end at a different diameter, that's why most CNC lathes don't have a compound.

Back about 2013 or so I bought a manual lathe (a 15" x 50 Clausing) and several Haas CNC lathes of similar design and capacity. By the time we added the taper attachment the manual lathe cost more than the CNCs.

We just finished turning some titanium rods that had a taper on one end from 1.1" to 1.575" diameters over a length of about 11 inches. (It's a #4-1/2 Morse taper) We cut a sample piece to confirm the dimensions (rather not screw up a $500 Ti blank) and they were right on the money. I probably would have to reset a taper attachment or compound at least once, probably more on a manual.

 

[KeithB]

Let me clarify what may seem contradictory posts. I HAVE used a taper attachment on several lathes when employed by the University. mostly to cut Morse tapers on special tools and tapered threads for custom pipe fittings. I DO NOT own a taper attachment for my personal manual lathe, but I have cut tapers on it using the compound. I currently cut all tapers on my CNC lathe, just a couple weeks ago we made a special driver for a tapered reamer with a #4 Morse taper shank. It fit the tailstocks of both lathes perfectly.

 

[Intheshop]

OK Keith,first off...I'm a certifiable metrology freak.There,I said it.To the point that I somehow thought that a clean room would make my life perfect?Did I learn anything,you bet,but it sorta goes over people's heads.

So,there needs to be balance.

Our machine shop is EXACTLY like our welding processes...it supports a bigger picture.

 

[smokeywolf]

Over the course of my machining career I've used a taper attachment maybe 10 times. 2 or 3 times to produce a Morse or B & S taper and 6 or 8 times to produce a tapered coupling between two lengths of titanium pipe that would be carrying a developer or bleach solution for film developing.

There are a lot of tools in the machine shop that are like a fire extinguisher. Not worth a darn till you have a fire. But when you do have that fire, nothing else will do. Don't think I've used my geometric die head more than 3 times. Each time it saved close to its own cost in man hours.