Type of thread used on coil spring compressor ?

[Other Daniel]

Having another look at the photo you posted earlier, I would hazard a guess
that it's a regular M14 x 2 thread.
It certainly looks like it's a V form.
Although you have given the spring compressor as an example, is it really
that critical, in your mysterious ( ) project what the thread actually is ?
Is it not a matter of simply making a choice between using a V form thread
or a trapezoidal one ?
And then choosing which major diameter would suit the project.
If you are providing both the threaded bar and the corresponding nuts,
why would it have to be an exact match with the spring compressor ?

 

[Other Daniel]

I have just been and got my own spring compressor out and had
a good look at it.
I can easily see that it has a trapezoidal thread form but I cannot
say if it is metric or acme.
Measuring it, I have a major diameter of 14.85mm with a pitch of
1.5mm.
Looking at online charts it doesn't seem to correspond to anything.
However, if I were to be fabricating something, I would just choose
it's nearest equivalent. So that would be either a TR14x2 or a TR16x2,
both of which are readily available. I wouldn't lose too much time
going down the rabbit hole of trying to exactly match my odd thread.
Please remember, we are all trying to help you resolve your question.

 

[demented]

Why would it have to be an exact match with the spring compressor ?

Because the thread used for Coil Spring Compressors and Bearing Pullers are used to exert force.

 

[Shox Dr]

Because the thread used for Coil Spring Compressors and Bearing Pullers are used to exert force.

All threads are designed to exert force.
V type threads take more force to set and release. Square form do not.

 

[Other Daniel]

Because the thread used for Coil Spring Compressors and Bearing Pullers are used to exert force.

And therein lies one of the main questions on this thread.
All threads (without exception) exert force. That is how they work.
It is the requirement of how that force is applied that determines
one threads suitability over another.
In addition to a force, a thread also provides gearing, which is an
important aspect to consider in it's application.

 

[demented]

I can easily see that it has a trapezoidal thread form but I cannot
say if it is metric or acme.
Measuring it, I have a major diameter of 14.85mm with a pitch of
1.5mm.
Looking at online charts it doesn't seem to correspond to anything.
However, if I were to be fabricating something, I would just choose
it's nearest equivalent. So that would be either a TR14x2 or a TR16x2,
both of which are readily available. I wouldn't lose too much time
going down the rabbit hole of trying to exactly match my odd thread.
Please remember, we are all trying to help you resolve your question.

Yeah, I agree forum members are trying to help and I appreciate all responses and opinions received.

However, at this point all I wanted is exactly what you've provided, which I thought could be achieved by sight or from described use.

Forum members imagining all the possible variable are overthinking the questions and dedicating too much time to my question.

However, I appreciate you've been good enough to measure your Spring Compressors and provide options available and also confirm your opinion in regard to it being a Trapezoidal Thread, which I'm uncertain of, as it's so different to the thread of the Scissors Jack and Vice but identical to the Thread of the Bearing Puller.

 

[demented]

All threads are designed to exert force.
V type threads take more force to set and release. Square form do not.

So why do Bearing Pullers and Spring Compressor use the same type of thread if all threads are the same.

I'm only trying to identity and source the thread type used for Coil Spring Compressors and Bearing Pullers.

 

[demented]

And therein lies one of the main questions on this thread.
All threads (without exception) exert force. That is how they work.
It is the requirement of how that force is applied that determines
one threads suitability over another.
In addition to a force, a thread also provides gearing, which is an
important aspect to consider in it's application.

No other thread needs to be considered, as I'm only attempting to identify and source the type of threads used for Coil Spring Compressor and Bearing Pullers.

 

[Shox Dr]

So why do Bearing Pullers and Spring Compressor use the same type of thread if all threads are the same.

I'm only trying to identity and source the thread type used for Coil Spring Compressors and Bearing Pullers.

Easier to apply force and release it.
V type threads are not designed to be in constant use.
Square type are.

Car jacks are made in millions and may never be used, why over engineer it.
Buy a cheap spring compressor and you'll get v form. As its never going to be used much.

Threaded bar in Square form is usually 12.9 grade.

 

[Other Daniel]

No other thread needs to be considered, as I'm only attempting to identify and source the type of threads used for Coil Spring Compressor and Bearing Pullers.

Right, but in the spirit of trying to perpetuate the confusion, whilst my coil
spring compressor has a trapezoidal thread form, all my bearing pullers
(all of good provenance) have a V thread form.
My vices do indeed have trapezoidal threads.
However, the photo you posted as an example looks, to me, very much
like a V form thread (metric or imperial too difficult to say from the photo).

 

[demented]

Easier to apply force and release it.
V type threads are not designed to be in constant use.
Square type are.

Car jacks are made in millions and may never be used, why over engineer it.
Buy a cheap spring compressor and you'll get v form. As its never going to be used much.

Threaded bar in Square form is usually 12.9 grade.

There is no need to be thinking of bar type or grade, as I'm only trying to identify the thread used on Coil Spring Compressor or Bearing Pullers and once I've confirmed the thread type, then I will source an appropriate grade of material.

Currently, what I consider to a normal threaded bar, meets my requirements and it does what I want it to, although I would much prefer to use the type of thread that is normally used on Bearing Pullers or Coil Spring Compressors, as I believe such a thread, due to its coarseness will withstand regular use better than a normal thread.

I don't need the thread from a car Jack, I only reference to the Jack and Vice as they have the Trapezoidal Thread, which looks totally different to the threads used on the Spring Compressors and Bearing Pullers.

 

[mtt.tr]

With the thread be run up and down often?

Grade 12.9 studding in what ever size is strong enough for the job.
Loads of load tables exist to get the size


My pullers are just fine thread

 

[Seadog]

Go for a buttress thread

 

[demented]

Yes, when in use the thread will be run up and down often, manually in the same capacity as a Coil Spring Compressor but many times per day, every day.

However, without appearing rude or ignorant, due to the know qualities and robustness of the coarse thread traditionally used on Hub Bearing Pullers and Coil Spring Compressor, for the same reasons, that's the thread I've decided to use, which I'm attempting to source.

I'm not convinced it's a Trapezoidal Thread but I may well be wrong, it's possibly a BSW or more than likely, a UNC Thread.

 

[PhillipM]

If I posted a photo of a specific car and I asked can someone identify it as I wish to buy one, would I be asked what's its intended use before I'm provided with the answer ?

You're basically posting a picture of a wheel nut and saying you need one similar for another car. Without knowing whether it's the same size, or thread, or will fit the other cars wheel even if it was.
It's not a good analogy.
There's no frame of reference in your photo for sizing, so we can't tell you what it is, and certainly not what strength grade it is - I've got 3 sets of spring compressors, one uses normal 8.8 M12x1.5 threaded bar and flexes on anything tricky - one uses 1/2" UNC, and one uses 5/8" ACME and will happily compress 1000lb race springs with little flex - it's not like they all use the same size and strength, the reason they all look similar in the photos you've looked at is the same reason we're struggling to help you - there's no frame of reference so they could be any of several sizes or threads.

Without knowing what you're actually trying to use the stuff for we're just going around in useless time wasting circles here.

 

[PhillipM]

However, without appearing rude or ignorant, due to the know qualities and robustness of the coarse thread traditionally used on Hub Bearing Pullers and Coil Spring Compressor, for the same reasons, that's the thread I've decided to use, which I'm attempting to source.

They're no more or less robust than any other coarse thread unless they're trapezoidal or acme (and that's generally used more because the tips of normal profile can get flattened against the spring than anything). They're often not even particularly strong material they're just the right size for the job.
This is the misconception.

 

[demented]

Go for a buttress thread

A buttress thread does appears to be a thread which can withstand more force of load in one direction than the other, which may be ideal.

Although, I'd much prefer to confirm the type used in the Coil Spring Compressors and Hub Pullers, as I assume technical experts have already done their homework and have come to the conclusion that the thread currently used, is the right one for the application.

 

[PhillipM]

They've just used whatever was cheap and big enough to do the job. That's it.
It's not some magic thread it's just whatever was off the shelf cheap enough to do what needs to be done. That's why you see all different sizes and threads used. It's also why the tolerance on almost all of them for thread to the nut is so loose they usually rattle around even with huge thread engagement lengths.
It's certainly no guarantee at all that it will work for what you're using it for, that's a very dangerous assumption to make for building anything.

 

[PhillipM]

Just for illustration:

This thread is certainly not the same as this one:

In form or size.
And many other spring compressors will use other form and other size threads too, same for pullers.
The picture you sent doesn't have any references for us to try to size it so all we can tell you is it looks like a pretty basic course thread. On a spring compressor set it's likely to be anywhere from M12 to M18 or 1/2UNC to 3/4UNC.
If it's robustness you're after then people have already pointed you to using trapezodial or square thread instead but the reason *that* is used on spring compressors is because you're much less likely to damage the top of the thread if it rubs against the spring when using it (since the springs bend as you compress them) - not because of any sort of wear advantage for using them frequently.

 

[demented]

You're basically posting a picture of a wheel nut and saying you need one similar for another car. Without knowing whether it's the same size, or thread, or will fit the other cars wheel even if it was.
It's not a good analogy.
There's no frame of reference in your photo for sizing, so we can't tell you what it is, and certainly not what strength grade it is - I've got 3 sets of spring compressors, one uses normal 8.8 M12x1.5 threaded bar and flexes on anything tricky - one uses 1/2" UNC, and one uses 5/8" ACME and will happily compress 1000lb race springs with little flex - it's not like they all use the same size and strength, the reason they all look similar in the photos you've looked at is the same reason we're struggling to help you - there's no frame of reference so they could be any of several sizes or threads.

Without knowing what you're actually trying to use the stuff for we're just going around in useless time wasting circles here.

A thread type is the same regardless or its size and diameter or are you saying the smaller or larger the size, then the thread type actually changes.

Also, my car anology can't be compared to a photo of a wheel nut as cars can have different size wheel studs with different size threads.

Where as a thread, regardless of it application it's the same.

Although I appreciate your contribution to my question and all your replies, if you can't identity the thread from its descriptive use and by the photos I've posted, then please stop overthinking my question.

I don't know the technicalities of my question but I asked, I want to use the same type of thread that's used on Coil Spring Compressors or Hub Bearing Pullers; that's all that's required and if it can't be answered from that, then I'm stuffed.

If the thread type can't be identified from the photos I provided, I'm also stuffed.

I just expected a forum member to know, from the top of their head, either from previous experience, its descriptive use or from the photo.