Accurately bending threaded rod
 

I have a new a product that will use two pieces, 4" long of 1/4-20 threaded
rod. Each piece will need to have two 20 degree bends, each bend will be
1-1/2" from each end and on the same plane. A Nylon insert locknut will
thread on each end about 1/2" to hold three pieces sandwiched together.
This is an angled variation on a standard product that uses two 1/4" x 4"
carriage bolts in a straight configuration.

I have to figure out how to bend the rod to the correct angle and on the
same plane without cracking the rod or boogering the threads where the nuts
go. The application doesn't require extreme strength, the cheapest
allthread is plenty strong if it isn't cracked.

The requirement is for 1k pieces per day at a total cost of =$.20 each

The problems I see are that the saw cut pieces have to be deburred to get a
nut started and if I bend the parts in a form on a punch press, I'd be
worried about smearing the threads and any secondary operation might push
the cost window. Ideally, I imagine a die that parts the rod and bends it
in one hit with a spring-loaded feeder that the operator drops in a standard
36" length of allthread every nine hits.

Accurately bending threaded rod
 

On Sat, 18 Jun 2011 07:48:59 -0400, Tom Gardner wrote:

The problems I see are that the saw cut pieces have to be deburred to
get a nut started and if I bend the parts in a form on a punch press,

Set up a grinder 4" before the saw so when the saw is through, the
grinder has just removed the threads.

Set the distance so the saw cuts half-way through the ground section.

4" rod drops into female die, male bends it while the next one is cut.

One part every time the machine cycles.

Accurately bending threaded rod
 

"Tom Gardner" wrote in message
...
I have a new a product that will use two pieces, 4" long of 1/4-20
threaded rod. Each piece will need to have two 20 degree bends, each bend
will be 1-1/2" from each end and on the same plane. A Nylon insert
locknut will thread on each end about 1/2" to hold three pieces sandwiched
together. This is an angled variation on a standard product that uses two
1/4" x 4" carriage bolts in a straight configuration.

I have to figure out how to bend the rod to the correct angle and on the
same plane without cracking the rod or boogering the threads where the
nuts go. The application doesn't require extreme strength, the cheapest
allthread is plenty strong if it isn't cracked.

The requirement is for 1k pieces per day at a total cost of =$.20 each

The problems I see are that the saw cut pieces have to be deburred to get
a nut started and if I bend the parts in a form on a punch press, I'd be
worried about smearing the threads and any secondary operation might push
the cost window. Ideally, I imagine a die that parts the rod and bends it
in one hit with a spring-loaded feeder that the operator drops in a
standard 36" length of allthread every nine hits.

How about bending solid rod, and then threading it.

Accurately bending threaded rod
 

Tom Gardner wrote:
I have a new a product that will use two pieces, 4" long of 1/4-20
threaded rod. Each piece will need to have two 20 degree bends, each
bend will be 1-1/2" from each end and on the same plane. A Nylon insert
locknut will thread on each end about 1/2" to hold three pieces
sandwiched together. This is an angled variation on a standard product
that uses two 1/4" x 4" carriage bolts in a straight configuration.

I have to figure out how to bend the rod to the correct angle and on the
same plane without cracking the rod or boogering the threads where the
nuts go. The application doesn't require extreme strength, the cheapest
allthread is plenty strong if it isn't cracked.

The requirement is for 1k pieces per day at a total cost of =$.20 each

The problems I see are that the saw cut pieces have to be deburred to
get a nut started and if I bend the parts in a form on a punch press,
I'd be worried about smearing the threads and any secondary operation
might push the cost window. Ideally, I imagine a die that parts the rod
and bends it in one hit with a spring-loaded feeder that the operator
drops in a standard 36" length of allthread every nine hits.


Well how about starting with preformed 4" sections instead of using long
pieces cut down?

I would contact a couple fastener companies and see what they have
available. For the numbers you need I would think they might want to do
business. I know you can buy all-thread at tractor supply as short as 8"
with clean threads (not cut pieces).

Then it would be simple to make a die set for the press that an
operator would lay 10 or so pieces in and hit the switch. repeat till
order is done.
With formed threads on each end no de-burr needed and no cutting in house.

--
Steve W.

Accurately bending threaded rod
 

Tom Gardner wrote:
... if I bend the parts in a form on a punch press,
I'd be worried about smearing the threads ...

Could the form/die be relieved where the to-be-used threads are so there
is no contact there? Bob

Accurately bending threaded rod
 

On Sat, 18 Jun 2011 07:48:59 -0400, "Tom Gardner"
wrote:

I have a new a product that will use two pieces, 4" long of 1/4-20 threaded
rod. Each piece will need to have two 20 degree bends, each bend will be
1-1/2" from each end and on the same plane. A Nylon insert locknut will
thread on each end about 1/2" to hold three pieces sandwiched together.
This is an angled variation on a standard product that uses two 1/4" x 4"
carriage bolts in a straight configuration.

I have to figure out how to bend the rod to the correct angle and on the
same plane without cracking the rod or boogering the threads where the nuts
go. The application doesn't require extreme strength, the cheapest
allthread is plenty strong if it isn't cracked.

The requirement is for 1k pieces per day at a total cost of =$.20 each

The problems I see are that the saw cut pieces have to be deburred to get a
nut started and if I bend the parts in a form on a punch press, I'd be
worried about smearing the threads and any secondary operation might push
the cost window. Ideally, I imagine a die that parts the rod and bends it
in one hit with a spring-loaded feeder that the operator drops in a standard
36" length of allthread every nine hits.


I'd put a couple of the suggestions above together.

Make 4" rods on a screw machine or CNC lathe with just the ends
threaded. Could do this yourself or farm it out. This would bend way
better than all thread and should be cheaper in manufacturing
quantities.

Bend a whole bunch at a time in a form die.

My advice is worth what you paid for it.

Karl

Accurately bending threaded rod
 

On Sat, 18 Jun 2011 07:48:59 -0400, "Tom Gardner"
wrote:

I have a new a product that will use two pieces, 4" long of 1/4-20 threaded
rod. Each piece will need to have two 20 degree bends, each bend will be
1-1/2" from each end and on the same plane. A Nylon insert locknut will
thread on each end about 1/2" to hold three pieces sandwiched together.
This is an angled variation on a standard product that uses two 1/4" x 4"
carriage bolts in a straight configuration.

I have to figure out how to bend the rod to the correct angle and on the
same plane without cracking the rod or boogering the threads where the nuts
go. The application doesn't require extreme strength, the cheapest
allthread is plenty strong if it isn't cracked.

The requirement is for 1k pieces per day at a total cost of =$.20 each

The problems I see are that the saw cut pieces have to be deburred to get a
nut started and if I bend the parts in a form on a punch press, I'd be
worried about smearing the threads and any secondary operation might push
the cost window. Ideally, I imagine a die that parts the rod and bends it
in one hit with a spring-loaded feeder that the operator drops in a standard
36" length of allthread every nine hits.

Can you build the machine around an induction heater so the bending
wouldn't bugger the threads?

--
Happiness comes of the capacity to feel deeply, to enjoy
simply, to think freely, to risk life, to be needed.
-- Storm Jameson

Accurately bending threaded rod
 

Tom Gardner wrote:

I have a new a product that will use two pieces, 4" long of 1/4-20
threaded
rod. Each piece will need to have two 20 degree bends, each bend will be
1-1/2" from each end and on the same plane. A Nylon insert locknut will
thread on each end about 1/2" to hold three pieces sandwiched together.
This is an angled variation on a standard product that uses two 1/4" x 4"
carriage bolts in a straight configuration.

I have to figure out how to bend the rod to the correct angle and on the
same plane without cracking the rod or boogering the threads where the
nuts
go. The application doesn't require extreme strength, the cheapest
allthread is plenty strong if it isn't cracked.

The requirement is for 1k pieces per day at a total cost of =$.20 each

The problems I see are that the saw cut pieces have to be deburred to get
a nut started and if I bend the parts in a form on a punch press, I'd be
worried about smearing the threads and any secondary operation might push
the cost window. Ideally, I imagine a die that parts the rod and bends it
in one hit with a spring-loaded feeder that the operator drops in a
standard 36" length of allthread every nine hits.

When you are talking a thousand a day, it probably makes more sense to
have the rods made on a screw machine, and then bend the straight parts
in a custom fixture. The screw machine cuts to length, threads the ends
only and makes them burr-free.

Jon