Claimed "1/4 watt" through-hole resistors from Amazon seller "Eamasawa" - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: September 16, 2020, 10:17:01 pm
content: Claimed "1/4 watt" through-hole resistors from Amazon seller "Eamasawa" - the 33K in each photo is of my own *actual* 1/4 watt stock, and the other is the claimed "1/4 watt" from an Amazon seller. The lead diameter, as you see, on the Amazon units, is a bit thinner.Am I being fussy? I expect to get what I paid for, no matter how small the cost!

author: TimFox
author_rank: Super Contributor
timestamp: September 16, 2020, 10:42:08 pm
content: You are being too fussy for a cheap part. Probably, it will dissipate 1/4 W safely--check its specification sheet (sarcasm).I grew up with Allen-Bradley carbon composition resistors, and mentally dimension resistors accordingly, but many modern resistors are not encased in phenolic and can probably withstand a higher core temperature.

author: coppercone2
author_rank: Super Contributor
timestamp: September 16, 2020, 10:55:14 pm
content: practically they suck for breadboarding and deadbugging is different (sometimes easier actually, because you do not disturb the other components pins if you make structures).If you actually are a breadboard guy, you should just pay more for real resistors, it will end up costing you eventually way more then the savings you get. IMO crap, I got real 1/6W resistors, those have the same leads as the cheap 1/4 watt resistors, real 1/4 watt resistors will poke your finger pretty hard. They make weak connections to breadboards and end up making circuits malfunction if the board is worn.

author: eti
author_rank: Super Contributor
timestamp: September 17, 2020, 12:03:43 am
content: Quote from: coppercone2 on September 16, 2020, 10:55:14 pmI don't know how to differentiate between crap and "real" resistors, especially on the world's largest commercial scam platform. How does one know which are best? Although not a king's ransom, I wouldn't exactly call £7.99 GBP "cheap", bearing in mind they appear rather inferior.Yes breadboard is my main use for these, so shall be pursuing Amazon for recompense, forthwith, and will leave them well alone, lesson learnt.Thanks so much for the help.

author: SilverSolder
author_rank: Super Contributor
timestamp: September 17, 2020, 12:07:58 am
content: If the resistor leads are about as thick as the jumper wires in your bread board kit, you are on the right track.A little thinner will work too, but can be fiddlier.Something like this looks ok:https://www.amazon.com/Elegoo-Values-Resistor-Assortment-Compliant/dp/B072BL2VX1I loved this very a propos assertion from the seller: "If you are upset with the loose connections of crappy ressitors, ELEGOO resistor kit with thicker pins would show you what a sturdy connection feels like."

author: eti
author_rank: Super Contributor
timestamp: September 17, 2020, 12:11:34 am
content: Quote from: SilverSolder on September 17, 2020, 12:07:58 amWell the decent grade ones I already had, were only JUST thick enough a lead diameter for breadboard, but I've lost most of them or they're all jumbled up, hence this purchase. I can't see these being much cop due to them being even thinner than the aforementioned! Never mind.

author: SilverSolder
author_rank: Super Contributor
timestamp: September 17, 2020, 12:14:06 am
content: See my edit above, I think the secret is to search for "bread board resistors" and you might find what you need!

author: eti
author_rank: Super Contributor
timestamp: September 17, 2020, 12:16:09 am
content: Quote from: SilverSolder on September 17, 2020, 12:14:06 amThanks so much

author: Monkeh
author_rank: Super Contributor
timestamp: September 17, 2020, 12:23:51 am
content: It's a 1/4W resistor - how thick of a lead do you think you need?You're being far too fussy and expecting everything to be made as if it's the glory years of material waste.

author: eti
author_rank: Super Contributor
timestamp: September 17, 2020, 12:30:29 am
content: Quote from: Monkeh on September 17, 2020, 12:23:51 amTake it easy. There's enough people "on a mission" as it is, online, to put everyone else down and try and make them feel stupid, without you needing to do so also. Since you're a member of this forum, I'm sure you're too intelligent to stoop to picking fault with strangers, and I'm maybe misreading your intentions. If I am, I apologise.However, please don't put words into my mouth, and don't presume to think you can read my mind. Please, I welcome you to think whatever you like, silently, and then go about your business.

author: SilverSolder
author_rank: Super Contributor
timestamp: September 17, 2020, 12:56:03 am
content: Quote from: Monkeh on September 17, 2020, 12:23:51 amIt feels good to work with nicely made stuff, and to work with tools that you feel are "just so". That's a good enough reason to pursue these things. If doing your hobby or work doesn't make you feel good, why are you doing it?That said, I can definitely also feel good about an economically optimal solution - if it is part of a product like a fridge or a TV where I don't really care about the aesthetics of the internal components!

author: floobydust
author_rank: Super Contributor
timestamp: September 17, 2020, 01:04:43 am
content: the chinese have optimized the cost of these resistors - using the least amount of metal for the leads. They're right - you don't need such thick leads for the currents involved. They're all steel nowadays. My 1980's Philips resistors are all copper leads. Sigh.You don't need the leads to be so long either, we're not doing point-point wiring building antique guitar amplifiers anymore. So the cheapened construction is ok I guess.But I found the 1% parts are around +/-4% and stayed with using higher quality parts made in Taiwan.

author: eti
author_rank: Super Contributor
timestamp: September 17, 2020, 01:53:29 am
content: Quote from: floobydust on September 17, 2020, 01:04:43 amI am unsure which resistors use ALL steel in the leads, but these are plated copper for sure - I have just tested them.

author: floobydust
author_rank: Super Contributor
timestamp: September 17, 2020, 03:07:25 am
content: A magnet tells all, and cutting steel leads they launch pretty far, even with safety cuttersName-brand resistor manufacturers state:"electrolytic copper-plated with fused pure tin {leads} are welded to the termination caps." (Vishay MBA and Yageo MFP)"Alloy coated leads""Hot tin dipped copper wire"

author: tkamiya
author_rank: Super Contributor
timestamp: September 17, 2020, 03:25:19 am
content: Ha! Someone with the same concerns as I...I've purchased registers from Amazon, too, and were quite surprised how thin the wires were. So far, for building purposes, they made zero difference. Wires form easily and hold shape. I never push 1/4 watt registers to the limit anyway. I think they are the result of cost cutting measure. Some dealers (like SparkFun) are starting to label their products as "thick lead" to differentiate from these.I'm so surprised at the length some manufacturers in China would go to cut cost.More concerning are their fuse holders. Some "18 gauge wire" looks like 22 gauge. Yet, spec'd at 15 or 20Amp. Some are now saying "real 18 gauge wire" in their ads. These days, for things that matter, I buy from Digikey. For ones they don't, eBay or Amazon will do.I hope Amazon will recognize being a conduit for these substandard parts will reduce them to second rate merchant, and affect future growth. Somehow, I doubt that will ever happen.

author: eti
author_rank: Super Contributor
timestamp: September 17, 2020, 03:44:04 am
content: Quote from: tkamiya on September 17, 2020, 03:25:19 amI hope Amazon will recognize being a conduit for these substandard parts will reduce them to second rate merchant, and affect future growth. Somehow, I doubt that will ever happen.Oh I believe they've been right down there at the very dregs of the barrel for a lonnnnnnnnnng time. They're the cheesiest, tackiest, most unethical, cheapest and lowest common denominator losers in all of retail.People can't seem to see past "cheap" and so people believe (falsely) that they "love Amazon" - no, they love being pandered to and being lazy, convenience-driven sheep that buy any old tat because it magically appears on their doorstep in 12 hours (and then flood eBay with it 6 months later, once they have played played with their little toy and then shoved it in a drawer somewhere).Amazon are literally the lowest of the lowest of the low, the bottom feeders. They disgust me, despite my using them rarely. Jeff Bezos is on the same planet that he and Elon "highly and disturbingly, and I think I'm changing the world" Musk, IE, definitely not planet earth.If ever there needed to be textbook examples of power going to one's head and disturbingly distorting your perception of reality, these two lads epitomise how NOT to be a responsible, adult, sane and kind CEO.

author: coppercone2
author_rank: Super Contributor
timestamp: September 17, 2020, 05:23:33 am
content: first of all, their not right, they are weak. I have damaged them doing circuit repairs that would be fine with normal resistors, particularly bending them out of the way. Package engineering is HUGE and its dictated by COST. They made it cheaper not better, you can make garbage run for a while. And again, it does not work on breadboards well, its not good for hobbyists. It's not fine for manufacturing either, because then you should specify a real 1/6 watt resistor if you need less power lolhow to avoid scams? Look up 'resistor manufacturers' on google. They will give you a datasheetbtw amazon is not a great company and not a great employer.. not sure you should associate with them on stuff that is a known problem.I should do a side by side over load test to see how they burn up compared to each other to see if the core is the same. Connect both and ramp up the wattage to see which one goes first, and how it goes, then do a pulse over load test to see the failure mode there (explosion characteristics, to see how much it will damage the circuit its in)I also have a hunch the leads are not electronics grade oxygen free pure copper, more like recycled pipe fittings. Another test you can do is get a real 1/6 or 1/8 watt part that has the same diameter lead, and then do a back and forth bend test to see which lead breaks faster. This also messes with the temperature coefficient of the device I think, so if you do the whole precise matching thing, you might be frustrated with drifty results if you think you can get a precision circuit on the cheap. Also the plating might be low quality, so it could make solder joints brittle.I also noticed the epoxy coating or whatever is more fragile on the cheap ones, they tend to fracture the ends when you bend them, this is a recipe for low moisture immunity and stuff if it compromises the package during part fitting prior to soldering.Then you might also want to test the paint, see how the marking paint holds up to elevated circuit temperatures, to see how repairable the part will be if it runs hot, fades the paint, then burn out, so you are left with a unlabeled dud in the circuit. Good resistors often burn out but still have legible markings.and when I measured them, their TCR is all over the place as compared to factory made resistors, which do much better then the datasheet usually, when comparing metal film to metal film. Batches do not line up, meaning unstable deposition I think, possibly also meaning poor film adhesion and low reliability.

author: Simon
author_rank: Unknown
timestamp: September 17, 2020, 07:01:41 am
content: I bought boxes of 5'000 resistors from china at one point and yes the wires were a bit thinner, not a problem really I just noted that they were not what I had bought before but when you think of the total accumulation of material used and weight to ship it's not a bad thing so long as they remain fit for purpose.

author: MosherIV
author_rank: Super Contributor
timestamp: September 17, 2020, 08:04:04 am
content: HiThe simple solution is just do not buy electronic components from Amazon or Ebay!You just do not know what you are goinb to get.There are plenty of reputable suppliers in the UK.Farnell and RS now sell to individuals but be aware they have a charge for postage if the order is below a minimum amount.Also look at RapidOnline and CPC.Then Mouser and Digikey do ship to UK.I use a small company called Bitsbox.co.ukTo be honest, they all either have postage charges or only give free postage above a minimum order amount.

author: HobGoblyn
author_rank: Unknown
timestamp: September 17, 2020, 08:39:30 am
content: As my wife has Amazon prime, it can be very handy ordering something at 9pm and get next day delivery.Needed a small length of 16 AWG silicone wire for my 3D printer, having it here the next day, was worth the £6.98 For 10ft.Farrell want £2.98 (plus 20% vat) per meter then there’s £5.95 delivery on top.When setting up my lab (only been doing this hobby a short while), the cheapish Chinese books of 0805 SMD resistors, the cheap sets of electrolyte caps, transistors and voltage regs I got from Amazon, are perfectly fine for my learning.That said, when I needed to replace a cap recently I didn’t use one from the cheap set, I got one from RS.I have noticed that Amazon has a lot of dodgy looking goods from 3rd parties on it, it also has a ton of incorrect descriptions from them where unless you read the entire spool of text, you probably won’t be getting what you think you’re getting. Sometimes there’s reviews pointing this out that are over a year or more old, but it’s still incorrect today.On Aug 24th I ordered Araldite Epoxy from Amazon, the title said “Araldite ARA-00007 Epoxy, Set of 6”. Looking at the price I knew it was only going to be 1, not 6. (but you never know).Sure enough only 1. Rather than complain in the reviews, I decided to try clicking on the “Report incorrect product information” and explained. I just clicked on same page, now the “set of 6” has been removed.The Amazon reviews are also usually pointless (99% positive etc) but reading the few negative reviews can give me an opinion of whether the fault is with the buyer (giving bad review because the don’t know what they are doing), or whether it’s total crap.

author: Siwastaja
author_rank: Super Contributor
timestamp: September 17, 2020, 08:40:34 am
content: When you need specifications, and parts that comply to said specifications, only buy from electronics distributors such as Digikey, Mouser, Element14/Farnell, or even lcsc.Only buy from Amazon/Ebay/Aliexpress when the proper distributors are a non-option. Some trivial connectors being horribly expensive at the distributors, but cheap and good enough on Aliexpress, comes to a mind as an example.But resistors are cheap even at the distributors. And you get the specs!

author: Simon
author_rank: Unknown
timestamp: September 17, 2020, 09:34:44 am
content: Amazon was never created for electronic components and yes many of the descriptions are useless. I often don't buy because clearly the seller is clueless which means I'll get wrong goods. As a seller myself I take pride in the fact that I know what I am selling and can answer technical questions. Amazon is just like ebay in fact both have been approaching each other in terms of practices baring ebay forking out for warehouses to try and take each other out.Sadly i could not compete with the likes of cheap chinese crap on ebay or the universality of Amazon and gave up on small parts years ago moving instead to very specific products that are not available everywhere as they are more niche.

author: Alti
author_rank: Frequent Contributor
timestamp: September 17, 2020, 12:16:21 pm
content: For breadboarding LEDs, SMPS and digital you need E3, maybe E6, 5 decades, maybe 5% 400ppm if you are picky. But for analog electronics you need E24, 1%, 50ppm at least.Although you rarely need sub 1R values for analog electronics, >10M is not uncomon.So, do not bother with Vishay pullups and do not bother with carbon resistors for analog electronics.

author: rsjsouza
author_rank: Super Contributor
timestamp: September 18, 2020, 12:53:18 am
content: IME there's nothing really new. I have seen this happen with capacitors of all brands for ages now... I usually store the bits I clip from the original leads and over the years I can tell which ones are newer and older. The first shrinking leads I saw were about twenty years ago when 1/8W through hole resistors started to become popular.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: September 18, 2020, 01:12:19 am
content: Quote from: Alti on September 17, 2020, 12:16:21 pmSo analog electronics did not exist before the 1960s-1970s when virtually all resistors were carbon composition? I agree that carbon composition has many drawbacks, but it is often suitable to purpose, even in analog electronics. If you are good enough to design such that the specs on resistors matter you should be good enough to spec resistors that meet the needs of your circuit.

author: Simon
author_rank: Unknown
timestamp: September 18, 2020, 06:52:11 am
content: who cares what the parts are made of? what are their specs? I find myself annoyed by the categories on the distributors sites, I don't care what the resistor technology is, I'll select the parameters I want and what I get I get.

author: eti
author_rank: Super Contributor
timestamp: September 18, 2020, 10:22:02 pm
content: Quote from: Simon on September 18, 2020, 06:52:11 am"Who"? Is there a universal answer to that? No. I think the engineers desinging Royal Navy torpedoes might care *A LOT*.You sound somewhat impatient - why would that "annoy" you; would you rather they HID such detail? I am sure you're pretty much alone there, if so.

author: Monkeh
author_rank: Super Contributor
timestamp: September 18, 2020, 10:24:41 pm
content: Quote from: Simon on September 18, 2020, 06:52:11 amThe method of construction is one of the specs. Resistors are not all equal.

author: amyk
author_rank: Super Contributor
timestamp: September 19, 2020, 02:03:23 am
content: Test their resistance and capability to withstand 0.25W. If they are within tolerance and dissipate 0.25W fine, they are fit for the purpose. The fact that the leads are thinner should not be a factor, because you didn't buy resistors specified by their lead diameter.

author: Simon
author_rank: Unknown
timestamp: September 19, 2020, 06:48:21 am
content: Quote from: Monkeh on September 18, 2020, 10:24:41 pmBut what specs does the construction affect? I look for a value, tolerance, ppm, wattage and temperature ratings, I expect that to automatically filter the right type of resistor. Same with capacitors although the construction is a bit more in my face there. I don't say "oh I need a polymer", I say "I need low ESR therefore I should look to a polymer", I don't use polymer because I want to use polymer. If I could filter caps of all types and i wanted ultra low ESR naturally the polymers would come at the top of results, if I filtered ot price the standard aluminiums would came on top.

author: Siwastaja
author_rank: Super Contributor
timestamp: September 19, 2020, 08:18:38 am
content: Simon is fundamentally right, you should primarily look at specs, and let the manufacturer choose the best internal materials and construction techniques to achieve the specs; it shouldn't matter.This being said, it really does not hurt to understand what goes into manufacturing of parts, because the spec sheets may fail to capture some important or difficult-to-put-in-numbers parameters.I have observed that many engineers, especially of older generations, do tend to rely too much on their intuitive generalization based on the "types" or "construction techniques" of the parts, and rules of thumb thereof. "Use a high-ESR capacitor at regulator output for stability." vs. almost all modern regulator ICs from the last 20 years are stable with zero ESR. The problem is, this unofficial data gets old; while spec sheets don't lie (except when theydolie!).But it would be stupid not to augment your design process with such experience, just keep the main focus on the actual data instead of generalizations and always be ready to challenge your own generalizations.

author: Simon
author_rank: Unknown
timestamp: September 19, 2020, 09:11:25 am
content: I read all chip datasheets very carefully especially regulators. Some say don't put more that "x µF" some say make sure the ESR is over this or under this. Of course it depends on what you are designing for. I usually have to work with -46 to +85-125 depending on location so what the thing is made of really falls out in the wash of the search. I spent 2 days picking inductors and capacitors for a switch mode regulator, but I will just use descriptive codes for resistors like 1kR_0805_1%_100ppm_-55/+125C and let the assembly deal with that. For bread boarding it really does not matter.

author: Simon
author_rank: Unknown
timestamp: September 19, 2020, 09:12:57 am
content: I have not too long ago heard completely contradictory views on tantalum's cause there is a mix of what modern parts do and what older people remember them as being some decades ago. I avoid them anyway based on price.

author: SilverSolder
author_rank: Super Contributor
timestamp: September 19, 2020, 11:52:03 am
content: Making a cost optimized product that still works well is a worthy engineering challenge. Choosing components that do the job well and reliably, while not costing much, probably requires "bending the rules" a little - the trick is to bend, rather than break them! I would guess it takes quite a bit of testing to end up with a good compromise.

author: floobydust
author_rank: Super Contributor
timestamp: September 19, 2020, 07:29:29 pm
content: Quote from: Simon on September 19, 2020, 09:12:57 amIt's not older people remembering what the parts were like decades ago- it's knowledge that electronic components have many parameters that aren't on the datasheets.Example is voltage derating tantalums, how much noise they have, their lifetime compared to ceramic capacitors which age as well.Example is 1/4W resistor voltage coefficient of resistance, difference between alloys on the leads, how much power they are good for in real life.

author: Simon
author_rank: Unknown
timestamp: September 19, 2020, 07:47:16 pm
content: I was thinking more their total fragility and tendency to easily blow short circuited. Others tell me this is no longer as bad as it used to be and new auto grade ones are fine.

author: HobGoblyn
author_rank: Unknown
timestamp: September 20, 2020, 10:07:35 am
content: As someone new to this hobby, the huge choice can be overwhelming.For example, if I want a 10uf 50v cap, RS gives me a choice of 101 through hole (plus another 76 surface mount).Sure some of those are the same one in bigger quantities but even so, I end up picking at random and because I’ve read Panasonic are good, if it’s to repair something, I usually choose them.Even if I tick the 5000 hr filter, I still get 7 different Ones (it lists 14 but duplicated in different quantities) to choose from.

author: Simon
author_rank: Unknown
timestamp: September 20, 2020, 02:31:34 pm
content: There is a huge variety of parts because of cost. At one end of the spectrum you have requirements for very low and high temperature with very long life, at the other end you have "it just has to last a year". Obviously there is different packaging which create duplicates. RS love to repackage everything where as other will do "cut tape" which is what RS effectively do by repackaging, re-reel give you a reel for and SMD assembly machine with whatever quantity you want or full reel as supplied by manufacturer. For hobbyists purposes you will just want cut tape. re-reeling costs per reel in the case of Farnell £3.50 but if you are an assembly house needing 2500 resistors it's maybe cheaper than buying a whole real of 5'000.As do different specs my thought experiment is that if you multiply all the specs together you will get a number that represents the price.

author: farpa
author_rank: Newbie
timestamp: August 30, 2021, 02:06:09 pm
content: Hello, do you happen to know where to obtain the datasheet for these resistors, I have sent an e-mail to the manufacturer but they have not responded.

author: EPAIII
author_rank: Super Contributor
timestamp: September 01, 2021, 09:53:07 am
content: Simple guidance: if you want a quality electronic part, buy from an electronic supply house, not Amazon.It really is that simple.