Why do US lamp parts use an "IP" thread ?

In summary, the conversation discusses the use of threaded tubing and IP thread standard in lamps in the USA, and questions whether Europe has a better approach. The speaker also expresses frustration with the inconvenience of having to buy specialized parts for lamps. The reason for this standard is believed to be for manufacturers to make more money, and it is a common trend in various industries due to historical accidents. The speaker also mentions their annoyance with Benjamin Franklin's arbitrary choice of polarity in electric charge and believes it will still be used in the future.
  • #1
Stephen Tashi
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Is there a reason (other than tradition) why lamps in the USA use threaded tubing that has an "IP" thread standard ?

Does Europe have a better approach ?

I find it irritating that the nuts and connectors in the main part of local hardware stores don't fit the threaded tubing in lamps. You have to shop in the "lamp parts" section of the store and the nuts and connectors there are (to me) inconveniently small and delicate.
 
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  • #2
Stephen Tashi said:
Is there a reason (other than tradition) why lamps in the USA use threaded tubing that has an "IP" thread standard ?

Does Europe have a better approach ?

I find it irritating that the nuts and connectors in the main part of local hardware stores don't fit the threaded tubing in lamps. You have to shop in the "lamp parts" section of the store and the nuts and connectors there are (to me) inconveniently small and delicate.
My belief is that this, like many such things, was done for a very simple reason. Money. If the manufacturers used standard parts, you could buy them from just anyone. This way you have to buy purpose-made parts and they make a bit of money on it. That's probably no longer true in that there are likely now many sources for such parts, but that's my belief about why it started that way.
 
  • #3
The threads are straight pipe threads. Most pipe threads you encounter (like in plumbing) are tapered. I read somewhere that electric lamps use the straight threads (and the pitches) originally used in the gas pipes in the gas lamp days. Presumably that made the customer's lives easier in 1910 or thereabouts.
 
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  • #4
"Historical accident" is the common answer to many such questions. And it is a very good reason. Consider the benefits of changing such a standard compared to the costs. Only rarely do the benefits outweigh the costs.

My pet peeve is the arbitrary choice that Benjamin Franklin made about which polarity of electric charge was called "positive". I wager that one million years from now, physicists will still be using Franklin's convention.
 
  • #5
anorlunda said:
"Historical accident" is the common answer to many such questions. And it is a very good reason. Consider the benefits of changing such a standard compared to the costs. Only rarely do the benefits outweigh the costs.

My pet peeve is the arbitrary choice that Benjamin Franklin made about which polarity of electric charge was called "positive".
I wager that one million years from now, physicists will still be using Franklin's convention.
And cussing all the while.
 

1. Why do US lamp parts use an "IP" thread?

US lamp parts use an "IP" thread because it is a standardized thread size that ensures compatibility and interchangeability with various lighting fixtures and accessories.

2. What does "IP" stand for in lamp parts?

"IP" stands for "intermediate pipe" thread, which is a type of thread commonly used in the US for lamp parts and fittings.

3. Are "IP" threads used in other countries?

Yes, "IP" threads are used in other countries, but they may be referred to as different names such as "NPT" (National Pipe Thread) in the US or "BSP" (British Standard Pipe) in the UK.

4. Can I use a non-"IP" thread lamp part with a US lamp?

It is not recommended to use a non-"IP" thread lamp part with a US lamp as it may not fit properly and could potentially cause damage to the lamp or fixture.

5. How do I determine the size of an "IP" thread on a lamp part?

The size of an "IP" thread on a lamp part can be determined by measuring the outside diameter of the male thread and counting the number of threads per inch. This will indicate the size and pitch of the thread. Alternatively, you can refer to a thread gauge tool for accurate measurement.

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