This is a general question, not for a specific application. It popped into my head while working on a minor home remodeling project last night. Has anyone had occasion to cut threads into a wooden hole using a tap?

It seems like a good hardwood, like oak or maple, would take the threading better than pine. If you don't torque the bolt down too tightly, or remove and reinstall it too frequently, it shouldn't wear out the threads for a long time. Or you could use a Teflon bolt. Or a wooden one, if there is such a thing.

Do you think that a bolt in a threaded hole would last longer than a screw which is removed and reinstalled infrequently?

Paul

On 4/10/2013 7:36 AM, Pavel314 wrote:
This is a general question, not for a specific application. It popped
into my head while working on a minor home remodeling project last
night. Has anyone had occasion to cut threads into a wooden hole
using a tap?

It seems like a good hardwood, like oak or maple, would take the
threading better than pine. If you don't torque the bolt down too
tightly, or remove and reinstall it too frequently, it shouldn't wear
out the threads for a long time. Or you could use a Teflon bolt. Or a
wooden one, if there is such a thing.

Do you think that a bolt in a threaded hole would last longer than a
screw which is removed and reinstalled infrequently?

Done regularly, but machine threads aren't nearly as deep nor coarse as
are the threads for wood screws and so won't last as well.

Clearly, the harder/denser the wood the more successful it can be but it
isn't a particularly strong nor successful venture (else't it would be
far more common, eh? )

--

In article ,
Pavel314 wrote:

This is a general question, not for a specific application. It popped into my
head while working on a minor home remodeling project last night. Has anyone
had occasion to cut threads into a wooden hole using a tap?

It seems like a good hardwood, like oak or maple, would take the threading
better than pine. If you don't torque the bolt down too tightly, or remove
and reinstall it too frequently, it shouldn't wear out the threads for a long
time. Or you could use a Teflon bolt. Or a wooden one, if there is such a
thing.

Do you think that a bolt in a threaded hole would last longer than a screw
which is removed and reinstalled infrequently?

Paul

On the PBS show Woodright's Shop I saw Roy make a woodworking vise that
had a threaded hole and shaft both made of wood. I'm pretty sure it
wasn't the usual Unified National thread form, but was probably an Acme
or hose coupling style thread. The diameter would have to be fairly
large to get the teeth deep enough to not strip out too easily. My first
choice would be to install some kind of threaded insert into the wood.
If for some reason that wouldn't work, I might try using a helicoil.

A cross dowel nut or a tee nut is probably a better solution.

On Apr 10, 5:36*am, Pavel314 wrote:
This is a general question, not for a specific application. It popped into my head while working on a minor home remodeling project last night. Has anyone had occasion to cut threads into a wooden hole using a tap?

It seems like a good hardwood, like oak or maple, would take the threading better than pine. If you don't torque the bolt down too tightly, or remove and reinstall it too frequently, it shouldn't wear out the threads for a long time. Or you could use a Teflon bolt. Or a wooden one, if there is such a thing.

Do you think that a bolt in a threaded hole would last longer than a screw which is removed and reinstalled infrequently?

Paul

Threads in a piece of wood that are sized to accept wooden threads
have to be much larger and coarser than metal or plastic threads.
Threading wood to convention machine screw dimensions is hardly worth
the extra work.. machine screw threads are WAY too fine for wood.

Wood is much less homogeneous (grain & directionality) than metal or
plastic and needs larger / coarser threads to overcome these issues.
The smallest wooden threads I've seen are around 1/2" ...maybe 3/8"

http://www.woodcraft.com/category/20...ding-kits.aspx

The typical way to create removable / resusable threads in wood is to
use metal or plastic thread inserts.
They have external coarse threads to interface with the wood &
internal machine screw threads.

http://www.woodcraft.com/category/20...d-inserts.aspx

Each type of thread works with the intended material.

On Wed, 10 Apr 2013 05:36:11 -0700 (PDT), Pavel314
wrote:

This is a general question, not for a specific application. It popped into my head while working on a minor home remodeling project last night. Has anyone had occasion to cut threads into a wooden hole using a tap?

It seems like a good hardwood, like oak or maple, would take the threading better than pine. If you don't torque the bolt down too tightly, or remove and reinstall it too frequently, it shouldn't wear out the threads for a long time. Or you could use a Teflon bolt. Or a wooden one, if there is such a thing.

Do you think that a bolt in a threaded hole would last longer than a screw which is removed and reinstalled infrequently?

Use a threaded insert into the wood and a machine screw into that.

Paul:

Yes, you can thread hardwood, and I've done it, but the problem is that machine screw threads are tiny and they screw simply doesn't hold that well.

Probably your best bet would be to use an "insert nut" instead of threading the wood itself. Insert nuts are commonly used for assembling furniture.



With an insert nut, you simply drill the correct size pilot hole, drive the insert nut in using the hex in the end as a drive, and then drive a machine screw into the internally threaded insert nut. You can buy aluminum insert nuts with and without flanges (to limit the depth they screw into the wood) in 1/4 X 20tpi size at Lee Valley.

I've driven aluminum insert nuts into spruce, but never into a harder softwood like fir, or a hardwood.

On 4/10/2013 8:43 AM, DD_BobK wrote:
On Apr 10, 5:36 am, wrote:
This is a general question, not for a specific application. It popped into my head while working on a minor home remodeling project last night. Has anyone had occasion to cut threads into a wooden hole using a tap?

It seems like a good hardwood, like oak or maple, would take the threading better than pine. If you don't torque the bolt down too tightly, or remove and reinstall it too frequently, it shouldn't wear out the threads for a long time. Or you could use a Teflon bolt. Or a wooden one, if there is such a thing.

Do you think that a bolt in a threaded hole would last longer than a screw which is removed and reinstalled infrequently?

Paul

...

The typical way to create removable / resusable threads in wood is to
use metal or plastic thread inserts.
They have external coarse threads to interface with the wood&
internal machine screw threads.

http://www.woodcraft.com/category/20...d-inserts.aspx

Each type of thread works with the intended material.

I had the screws for a front door hinge strip. I used this kind of
insert and it worked well.

Pavel314 wrote:
This is a general question, not for a specific application. It popped
into my head while working on a minor home remodeling project last
night. Has anyone had occasion to cut threads into a wooden hole
using a tap?

Yes, numerous times. In sizes ranging from 8-32 to 1/2-20. As long as you
are going cross grain, they work out fine. Going long grain is less good
because the treads are weak and break off easily, even while tapping. One
can get around that but not easily.

FWIW, the mahogany head of my cane screws onto the hickory shaft. All wood
threads. I made it 2-3 years ago, still as good as gold. It's removeable
because I have other heads...if I get bored with mahogany I can use walnut,
sap hickory or sap hickory stained black. I also have a black hickory shaft
for more formal occasions. Like funerals

It seems like a good hardwood, like oak or maple, would take the
threading better than pine. If you don't torque the bolt down too
tightly, or remove and reinstall it too frequently, it shouldn't wear
out the threads for a long time. Or you could use a Teflon bolt. Or a
wooden one, if there is such a thing.

Do you think that a bolt in a threaded hole would last longer than a
screw which is removed and reinstalled infrequently?

No idea. You can improve the longevity of either by hardening the inside of
the hole with super glue.



--

dadiOH
____________________________

Winters getting colder? Tired of the rat race?
Taxes out of hand? Maybe just ready for a change?
Check it out... http://www.floridaloghouse.net

On Apr 10, 8:36*am, Pavel314 wrote:
This is a general question, not for a specific application. It popped into my head while working on a minor home remodeling project last night. Has anyone had occasion to cut threads into a wooden hole using a tap?

It seems like a good hardwood, like oak or maple, would take the threading better than pine. If you don't torque the bolt down too tightly, or remove and reinstall it too frequently, it shouldn't wear out the threads for a long time. Or you could use a Teflon bolt. Or a wooden one, if there is such a thing.

Do you think that a bolt in a threaded hole would last longer than a screw which is removed and reinstalled infrequently?

Paul

Another option not yet discussed is as follows:

1 - Drill a hole through the face of the wood just big enough to
accept the shaft of your bolt.
2 - Bore a hole on the back side of the wood large enough to accept
the correct size nut for the bolt.
3 - Coat the threads of the bolt with Vaseline, slip it through the
hole and into the nut.
4 - Pour epoxy around the nut to secure it in place.

The Vaseline coated threads will allow you to remove the bolt after
the epoxy cures. When viewed from the face, all you'll see is a small
hole in the wood, but there will be a nut behind it to accept the
bolt.

On Wednesday, April 10, 2013 3:26:04 PM UTC-4, DerbyDad03 wrote:
On Apr 10, 8:36*am, Pavel314 wrote:

This is a general question, not for a specific application. It popped into my head while working on a minor home remodeling project last night. Has anyone had occasion to cut threads into a wooden hole using a tap?



It seems like a good hardwood, like oak or maple, would take the threading better than pine. If you don't torque the bolt down too tightly, or remove and reinstall it too frequently, it shouldn't wear out the threads for a long time. Or you could use a Teflon bolt. Or a wooden one, if there is such a thing.



Do you think that a bolt in a threaded hole would last longer than a screw which is removed and reinstalled infrequently?



Paul



Another option not yet discussed is as follows:



1 - Drill a hole through the face of the wood just big enough to

accept the shaft of your bolt.

2 - Bore a hole on the back side of the wood large enough to accept

the correct size nut for the bolt.

3 - Coat the threads of the bolt with Vaseline, slip it through the

hole and into the nut.

4 - Pour epoxy around the nut to secure it in place.



The Vaseline coated threads will allow you to remove the bolt after

the epoxy cures. When viewed from the face, all you'll see is a small

hole in the wood, but there will be a nut behind it to accept the

bolt.

This is a common method. Usually one mixes glass microspheres with the epoxy. Or you can just use a bit of Bondo.

TimR wrote:
On Wednesday, April 10, 2013 3:26:04 PM UTC-4, DerbyDad03 wrote:
On Apr 10, 8:36 am, Pavel314 wrote:

This is a general question, not for a specific application. It popped
into my head while working on a minor home remodeling project last
night. Has anyone had occasion to cut threads into a wooden hole using a tap?



It seems like a good hardwood, like oak or maple, would take the
threading better than pine. If you don't torque the bolt down too
tightly, or remove and reinstall it too frequently, it shouldn't wear
out the threads for a long time. Or you could use a Teflon bolt. Or a
wooden one, if there is such a thing.



Do you think that a bolt in a threaded hole would last longer than a
screw which is removed and reinstalled infrequently?



Paul



Another option not yet discussed is as follows:



1 - Drill a hole through the face of the wood just big enough to

accept the shaft of your bolt.

2 - Bore a hole on the back side of the wood large enough to accept

the correct size nut for the bolt.

3 - Coat the threads of the bolt with Vaseline, slip it through the

hole and into the nut.

4 - Pour epoxy around the nut to secure it in place.



The Vaseline coated threads will allow you to remove the bolt after

the epoxy cures. When viewed from the face, all you'll see is a small

hole in the wood, but there will be a nut behind it to accept the

bolt.

This is a common method. Usually one mixes glass microspheres with the
epoxy. Or you can just use a bit of Bondo.

A while back I was building something that needed a heavy wooden base. I
also needed to bolt and unbolt items to the base each time we set it up.
Instead of using regular nuts, I cut 3/4" steel rod into 1" lengths, tapped
them to accept bolts and then used the method described above to epoxy them
into the board. Between my son and I we made about 50 round nuts out the
rod. Once things were bolted down, it was a heavy, sturdy structure.

On 4/10/2013 1:26 PM, DerbyDad03 wrote:
On Apr 10, 8:36 am, wrote:
This is a general question, not for a specific application. It popped into my head while working on a minor home remodeling project last night. Has anyone had occasion to cut threads into a wooden hole using a tap?

It seems like a good hardwood, like oak or maple, would take the threading better than pine. If you don't torque the bolt down too tightly, or remove and reinstall it too frequently, it shouldn't wear out the threads for a long time. Or you could use a Teflon bolt. Or a wooden one, if there is such a thing.

Do you think that a bolt in a threaded hole would last longer than a screw which is removed and reinstalled infrequently?

Paul

Another option not yet discussed is as follows:

1 - Drill a hole through the face of the wood just big enough to
accept the shaft of your bolt.
2 - Bore a hole on the back side of the wood large enough to accept
the correct size nut for the bolt.
3 - Coat the threads of the bolt with Vaseline, slip it through the
hole and into the nut.
4 - Pour epoxy around the nut to secure it in place.

The Vaseline coated threads will allow you to remove the bolt after
the epoxy cures. When viewed from the face, all you'll see is a small
hole in the wood, but there will be a nut behind it to accept the
bolt.


If you can get to the back side you can use a t-nut.
http://www.lowes.com/SearchCatalogDi...051&Ntt=t+nut#!

The barbs keep it from turning. Only one hole is needed.