What are the physical dimensionl specifications a of ¼W 5% resistor

spinnaker

Joined Oct 29, 2009
7,837
I have seen them some in a couple different dimensions for through hole. Though the total length might be standard.

You have been around long enough. Don't you have enough samples to just measure them?
 

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Wendy

Joined Mar 24, 2008
21,914
My electronics are in my garage, my wheelchair doesn't go there. Can't handle steps or grass.

lt has been most 3 years since I've been there.

Doesn't stop me from using my computer though.
 
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dl324

Joined Mar 30, 2015
9,335
I don't think there's a standard now because the low quality resistors tend to use lead wire that's too thin.

FWIW, here's something I had handy for Panasonic resistors:
upload_2019-3-23_19-44-30.png

upload_2019-3-23_19-44-58.png

SEI carbon film:
upload_2019-3-23_19-50-12.png

upload_2019-3-23_19-50-40.png

More from a Chinese company:
upload_2019-3-23_19-48-0.png
upload_2019-3-23_19-46-41.png

upload_2019-3-23_19-46-59.png
 

JohnInTX

Joined Jun 26, 2012
3,917
I use .400" spacing for 1/4W carbon films on a PC board if that helps. Leaves room for pads and bend radii for the leads.
Since the body is <300", I've been known to use them in .300" DIP component carriers like these
 

Thread Starter

Wendy

Joined Mar 24, 2008
21,914
Thank You everyone,I am designing a E24 resistor storage tray to be printed. Whoever made the dim chart for Panasonic needs their pee-pee thwacked, what in the heck is min? This after they said all measurements were in mm so that is what I went with. I got the following numbers:

Diameters:All were just under 0.10" so that is what I will use.

Lenthths
Panasonic 1.824"
SEI 2.456"
CIC 2.22"

I figure a tray that is 2.5" X 2,00" X 1.00" L x W x D will hold 200 parts with room to spare for resistors that have been formed.
 
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ian field

Joined Oct 27, 2012
6,539
So far I the body is 2.29x6.35mm I got this off a web site when I Googled the title of this thread. The thing I am having a little trouble with is what is the total length before the leads are trimmed down, This is part of a larger project I am currently working on. Any help is appreciated. Thank you in advance.

https://forum.digikey.com/t/physical-size-of-a-through-hole-resistor/756
You can't just blindly ignore construction method - some are more efficient at getting rid of heat than others. I've seen some pretty chunky resistors that are only rated 1/4W.

Modern resistors are more likely to have rating obvious from physical size - but its more reliable with SMD parts.

When Maplin was still about - they did 0.6W with high end spec that were no bigger than regular 1/4W.
 

Thread Starter

Wendy

Joined Mar 24, 2008
21,914
This is the second 1/4 W 5% resistor storage methodology I have come up with, so I am not a novice. The first one has proved its utility time and time again for me. A bit early to be critical of a concept don't you think? The hard part is actually buying the parts without breaking the bank, and I have started a separate thread in the Marketplace forum for that. To each their own. WhenI make it I will post it. Shoot, I may even sell them, if their is an interest. 3D printing is cheap and easy. but hard to do for some folk.
 
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ian field

Joined Oct 27, 2012
6,539
This is the second 1/4 W 5% resistor storage methodology I have come up with, so I am not a novice. The first one has proved its utility time and time again for me many times. A bit early to be critical of a concept don't you think? The hard pat is actually buying the parts without breaking the bank, and I have started a separate thread in the Marketplace forum for that. To each their own. I make it I will post it. Shoot, I may even sell them if ,their is an interest. 3D printing is cheap and easy. but hard to do for some folk.
BUY?!!! - salvage wins every time. There's not much wrong with SH resistors etc - and a recent dumpster dive scored an impressive bundle of anti static sticks. large quantity of unused 10A 45V SB rectifiers and 60V 45A MOSFETS + loads of other sundry items. Yesterday's haul was 18x GU10 LED bulbs. My latest project is on bought prototyping board - everything else is salvage.
 

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Wendy

Joined Mar 24, 2008
21,914
OK Salvage , this is getting off topic, If I want a specific part I like the luxury of having it.
 

Thread Starter

Wendy

Joined Mar 24, 2008
21,914
I do this. to keep my mind busy, I have a deep collection of parts I haven't seen since the stroke. Frustrating doesn't begin to describe it.

If I had your phone number we could talk about it hour after unending hour.A bored electronics nerd with nothing better to do.
 

WBahn

Joined Mar 31, 2012
24,977
Thank You everyone,I am designing a E24 resistor storage tray to be printed. Whoever made the dim chart for Panasonic needs their pee-pee thwacked, what in the heck is min? This after they said all measurements were in mm so that is what I went with. I got the following numbers:
The "min" is minimum. The leads are 20 mm long minimum -- they could be longer, but will be at least 20 mm.
 

ian field

Joined Oct 27, 2012
6,539
I do this. to keep my mind busy, I have a deep collection of parts I haven't seen since the stroke. Frustrating doesn't begin to describe it.

If I had your phone number we could talk about it hour after unending hour.A bored electronics nerd with nothing better to do.
Recently found a Voip handset I'd totally forgotten I had. Pretty sure using my mobile would be way beyond my budget.

Could've chatted on FB - but I got 7 days FB jail finding out they're NOT politically neutral!
 
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MisterBill2

Joined Jan 23, 2018
4,579
Resistor prices vary widely between sources, I have seen. at least a 5 to 1 ratio among the common suppliers. Part of that may be quality, but the less expensive ones were totally OK when run conservatively. From some sources the price ratio was more like 12 to 1. That was a few years back but I doubt it has changed much. Unfortunately I do not recall the supplier names.
 

dl324

Joined Mar 30, 2015
9,335
Looking at Jameco catalogs, I see that through hole resistor prices have gone up about 4X in the last decade.

My gripe with the cheap ones is that the leads are so thin that they tend to bend when trying to insert into a solderless breadboard.

It also annoys me that manufacturers are making smaller resistors with higher power ratings (e.g. SEI CF 1/8 and CFM 1/4 are the same physical dimensions but one is rated for twice the power). If you don't have a schematic, you have to do power calculations to see what should be used.
 

MisterBill2

Joined Jan 23, 2018
4,579
Looking at Jameco catalogs, I see that through hole resistor prices have gone up about 4X in the last decade.

My gripe with the cheap ones is that the leads are so thin that they tend to bend when trying to insert into a solderless breadboard.

It also annoys me that manufacturers are making smaller resistors with higher power ratings (e.g. SEI CF 1/8 and CFM 1/4 are the same physical dimensions but one is rated for twice the power). If you don't have a schematic, you have to do power calculations to see what should be used.
Some technologies allow higher powers than others. AND, the last time that I looked, Jameco was one of the most expensive sources of parts , which is why I do not buy things from them.
 

Thread Starter

Wendy

Joined Mar 24, 2008
21,914
Actually that is simply not true. Tanners has all types, and I get to define what I want.

Women and cats do as they please, and Men and Dogs just have to get used to the idea.
.......................Robert A. Heinlein
 
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