Threaded Rod End Dressing

[garboui]

I am looking for a tool that either cuts and dresses or just dresses the end of cut threaded rod. This is primarily for cut lengths of 1/4-20 Nylon allthread. Nylon self locking (interference) nuts are used with the threaded rod. Unless the ends are dressed just right the nuts will bind to the threaded rod.

If there is a tool for this I would really like to know as dressing the ends by clipping the leading thread in to a taper or sanding on a belt sander is tedious and not always successful in not having the nuts bind.

 

[rlitman]

Why not screw on a nut, cut it, and then take the nut off?

 

[383 240z]

I just roll the edge over on my belt sander. Works every time. Keith

 

[bobcatdan]

I do both of the above.

 

[454ragtop]

Never worked with nylon threaded rod, but can't help wonder if a pencil sharpener would work?
HTH, Jim

 

[70Chevy]

Belt sander.

 

[Mickey O]

There's a variety of tooling that will do what you're looking to achieve, they ain't all that cheap though but if you're doing a lot t might be worth investing. If you have a router table you could make a jig and use a straight cutter. For the tooling do a search for Severance rod chamfering bits or rod forming bits:

 

[DSLTRK]

Why not screw on a nut, cut it, and then take the nut off?

+1 This is the correct way short of finishing the rod with a CNC machine. The nut also cleans any burrs from the cutting.

 

[demographic]

Why not screw on a nut, cut it, and then take the nut off?

That^

 

[05firecatf7black]

They make a pair of shears for 3/8 threaded rod,cut easily and no bur

 

[garboui]

This is a production application im looking for. The Chamfering bits posted doo look like they may work if not to aggressive whn cutting in to the nylon.

For those recommending threading a nut on first, this is not suitable for 2 reasons. Its all nylon hardware and as such wont work. We already have shears that can make a burr free cut leaving a sharp starting thread. If the former did work, this method is just too time consuming.

 

[A_Pmech]

How many of these do you have to do?

What is the length of the threaded rod?

 

[MotoDave]

unless its a weird size, just use normal steel nuts

 

[srmofo]

This is a production application im looking for. The Chamfering bits posted doo look like they may work if not to aggressive whn cutting in to the nylon.

For those recommending threading a nut on first, this is not suitable for 2 reasons. Its all nylon hardware and as such wont work. We already have shears that can make a burr free cut leaving a sharp starting thread. If the former did work, this method is just too time consuming.

Use steel nuts instead of the nylon nuts to clean the threads. Then just thread on the appropriate nylon.

Personally I would try a thread chaser if the nut didnt work. Chasers tend to cut the nasty bits off rather than push them to the side where they can cause problems later on.

 

[garboui]

How many of these do you have to do?

What is the length of the threaded rod?

Hundreds. Its a production item for a product so its also an ongoing thing.

60-80mm

unless its a weird size, just use normal steel nuts

Metallic components are not feasible.

 

[jayrush13]

For dressing 3/8 rod I was shown a trick by a journeyman of mine. He would use a big blue wire nut like the size for #6 wire and it chased the threads perfectly. You might look at a smaller wire nut there may be one the perfect size

 

[Provincial]

It sounds like you need to make something similar to a Drill Doctor to dress the ends. In essence, a diamond(?) wheel at an angle to a tubular guide with a stop. The rod would be inserted and rotated one revolution against the wheel to knock the corner off the square end of the rod. The depth stop would bear against the end of the rod to keep the depth of engagement constant. With the right abrasive, feed, and speed you would get a clean cut on the nylon.

I suggest a diamond wheel because I know that nylon is abrasive and you don't want to have to keep adjusting the tool. It should be easy and foolproof enough to use minimal-skilled labor.

I would also be experimenting with alternatives to the current nylon nut, which seems overly picky about mating threads. A few cents difference in nuts (or an alternate supplier) could eliminate the need to dress the ends of the threads.

 

[vintagefan]

This is what you want to use:



It's an OD deburring tool, basically an inside-out countersink/chamfer bit. It's normally mounted on a handle, but can easily be adapted to a hand drill.

I have used this exact bit on 1/4-20 nylon threaded rod, and it works just fine.

It's important to use single flute with plastic, so that it doesn't bite, that's what makes the above bit particularly suited.

The model number for the above bit is Shaviv F26X