Buying (Genuine!) Parts from China

[itdontgo]

I'm after buying 250 SIM900 GSM modules for one of our products.  I have a supplier in China who I have dealt with in the past but decided to look around Alibaba for an alternative/cheaper parts.  I found one.

$10.37USD vs. $13.70 from our existing supplier.  That's over $800+TAX difference.

Obviously my existing supplier chose to remind me that there are lots of 'fake' modules around and that they are 100% genuine (theirs' are) even if I used escrow services.

Does anyone have any idea what questions to ask when buying parts from China to find out whether they're real?  I suppose asking for serial numbers might just piss them off!

[T4P]

it's a minefield ... either you get blown up or you get ripped off

[Short Circuit]

Don't forget that 250 times $10 is still a small order, so payment in advance or extra cost for Escrow.

On payment in advance; for some traders $2500 is more than enough to justify leaving with the money...

[bilko]

If the unit price is $10.70 rather than $13.70, you can be certain of one of two things
Either your initial supplier was ripping you off by 30%  per unit or
your prospective supplier is selling you junk / fakes/ rejects or has no intent in supplying you at all.

There is no way that a legit supplier can shave off 30% for such a small order value, you would have to negotiate extremely hard to get even 5% extra discount

[Michael Weston]

Does anyone have any idea what questions to ask when buying parts from China to find out whether they're real?  I suppose asking for serial numbers might just piss them off!

While I do not have your answer directly, I know the people at Dangerous Prototypes have experience that could help you.  Maybe you should ask them in their forum.

[vk6zgo]

I'm after buying 250 SIM900 GSM modules for one of our products.  I have a supplier in China who I have dealt with in the past but decided to look around Alibaba for an alternative/cheaper parts.  I found one.

$10.37USD vs. $13.70 from our existing supplier.  That's over $800+TAX difference.

Obviously my existing supplier chose to remind me that there are lots of 'fake' modules around and that they are 100% genuine (theirs' are) even if I used escrow services.

Does anyone have any idea what questions to ask when buying parts from China to find out whether they're real?  I suppose asking for serial numbers might just piss them off!

Go ahead & piss them off!
Too many people are so worried about "cultural sensitivity" & "making them lose face" that they bend over backwards & "lose face" themselves,so if the supplier isn't honest,they know they have a "sucker",& will play it for all it's worth!
If they are honest Chinese business people, they will expect you to try to protect yourself,& if they are crooks,who cares if they are pissed off!
Remember,that if the parts do work,but are not full spec & fail after a while,it's your customers who will be yelling--at you!!

[Bored@Work]

Chinese vendors have a *cough* non-standard *cough* interpretation of the meaning "in stock", i.e. they are freaking liars. Ask them at least three times if they really have the item in stock - as in having the parts in their hands, not as having a rough idea they might be able to get them in five month.

[HardBoot]

My experience with China... very low prices, random quality, slow delivery.

Haven't had many bad experiences relative to the very large number of purchases I've made, I've had just as many problems with "western" sellers.

Hard to resist 3 linear regulators for 99 cents including shipping, when a "western" seller would charge much more than that for shipping alone.
The only thing I'm weary about is electrolytic capacitors.
Haven't got anything used yet.

[amyk]

Chinese vendors have a *cough* non-standard *cough* interpretation of the meaning "in stock", i.e. they are freaking liars. Ask them at least three times if they really have the item in stock - as in having the parts in their hands, not as having a rough idea they might be able to get them in five month.

Their idea of "in stock" is "we may be able to sell you some".

[HardBoot]

Chinese vendors have a *cough* non-standard *cough* interpretation of the meaning "in stock", i.e. they are freaking liars. Ask them at least three times if they really have the item in stock - as in having the parts in their hands, not as having a rough idea they might be able to get them in five month.

Their idea of "in stock" is "we may be able to sell you some".

For me it's been "it's in stock, eventually"

[johnboxall]

I'm after buying 250 SIM900 GSM modules for one of our products.  I have a supplier in China who I have dealt with in the past but decided to look around Alibaba for an alternative/cheaper parts.  I found one.

$10.37USD vs. $13.70 from our existing supplier.  That's over $800+TAX difference.

If you're happy with your existing supplier - ask yourself "how much will it cost me to get out of the shit if I get fakes/duds from the new unknown seller?"

[tom66]

I would say if you do it, first order samples and check them (complete tear down.) And when in production tear apart one in ten of each module and compare the internal gubbins.

[bilko]

I would say if you do it, first order samples and check them (complete tear down.) And when in production tear apart one in ten of each module and compare the internal gubbins.

If you have to tear down 1 in 10 you might as well pay the $3 extra per unit because it will cost far more than $30 for each tear down and then you are still playing russian roulette with future quality. No guarantee that production units will be sourced from the same supplier as the sample units.

[grumpydoc]

I suppose asking for serial numbers might just piss them off!

A legit supplier will give you the serial numbers.

If they get pissed off with a relatively simple request then possibly you don't want to deal with them anyway.

[JonnyBoats]

I have a friend who is American and working in Shengen (sp?) China. He was telling me about a project he was working on there (in China) where they were doing 100% testing of the boards produced. The first 100 passed and the all the rest failed.

It turned out that one reel of ICs used in the pick and place machine had 100 good chips loaded on the front of the reel and all the rest were simply plastic with no die inside!

Needless to say this was an expensive mistake and the supplier refused to make good.

According to him, there is no end to the creative and convoluted ways that suppliers there will go to to shave pennies and screw the customer if they can.

Of course if you are a bug fish like Apple it is a completely different story.

[48X24X48X]

Samples might be original parts, subsequent big orders might be fake.
Some parts might work for general purpose use but when goes nearer to the upper point of specification, it fails.
An example would be a regulator 'capable' of 1A output. At times, your application might probably use only a portion of that rating. So, they stuffed in smaller die that 'works' for the lower current rating.  So, if you really drive it harder (within 'specification'), that's when it fails.

[Uncle Vernon]

I'm after buying 250 SIM900 GSM modules for one of our products.  I have a supplier in China who I have dealt with in the past but decided to look around Alibaba for an alternative/cheaper parts.  I found one.

$10.37USD vs. $13.70 from our existing supplier.  That's over $800+TAX difference.

If you're happy with your existing supplier - ask yourself "how much will it cost me to get out of the shit if I get fakes/duds from the new unknown seller?"

I'll have to concur. You could do $800 in cost from a single sale. Sure source, test and check a few cheaper parts maybe for future batches. You can get some ideas of delivery, capabilities, communications etc. along the way.
 But to put stuff of unproven origin into production runs is simply commercial suicide.

[grumpydoc]

According to him, there is no end to the creative and convoluted ways that suppliers there will go to to shave pennies and screw the customer if they can.

They must assume that "The West" is a big enough place that they never need the same customer twice!

[HardBoot]

About 15 days ago I made 12 separate orders from 6 different Chinese sellers, 3 things have arrived so far:

Three L7805's for $0.99 shipped, the exact same part at Mouser is 65 cents for 1, and Mouser doesn't do free shipping unless you make an order over $200.

1000ft of 30 Ga tinned copper wire, $13 shipped. AND THEY GAVE ME A $5 COUPON.

Ten 1N5408 Power Diodes, $1.29 Shipped, 27 cents each at Mouser. The drop is 1.22v which is within spec, haven't managed to pop one with 400 volts.


If all of these goes well... I'm calling calling it... American parts sellers are generally not worth the money over reputable Chinese sellers.
I just haven't had enough problems, it's been about the same, but the price difference, damn, huge.

[T4P]

HardBoot ...
buying from them a SECOND time becomes a disaster (I know you bought from aliexpress)
And you will never know how many of a quantity you bought might work ( let's say 100) maybe you picked 30 out of 100 and they all work good within spec, but the 70? Hard to say

[poorchava]

It's important to locate honest (or rather less dishonest than the others) sellers and keep purchasing stuff from them.

My example: i was looking forward to buy Toshiba TB6560AHQ stepper driver IC. Target quantity was ~100 per lot.

Normal vendors offer it at about $10 at single quantity and around $5-$6 at 100pcs. Ebay: $3.5. I purchased 5pcs of ebay ones and compared against ones bought from 'reputable' supplier (tme.eu). They are the same. I've even exachanged those on the same pcb and they perform exactly the same. I've abused them in every possible way and they behave exactly the same. Even considered decapping them, but decided there's no point in that.

I've ordered 2 more batches of 5 pcs from ebay to check if the guy didn't try to lure me into buying fakes. Now I'm gonna probably order 100 pieces and we're gonna see. So far he didn't rip me off and I started purchasing other stuff from that guy even if he's not the cheapest one at some items. And yeah... when facing 330% price difference at suingle quantities and about 200% at 100s I'm willing to take the risk

[Short Circuit]

About 15 days ago I made 12 separate orders from 6 different Chinese sellers, 3 things have arrived so far:
...

All ittibity orders, most likely all from ebay.
There's a world of differemce between buying a few standard parts from eBay (which does have a reasonably
working way of seller rating), and buying substantial amounts of higher-value parts from a vague Chinese broker.
You really cannot upscale hobby activities to serious business and assume things will work the same only with
a higher quantity.

I also have bought hunderds of 'free shipping' items from HD/PRC based eBay sellers with no problem.
I also have bought for many 10's of thousands of dollars from brokers. Again, small orders seldom a problem,
but when the amounts go over few hunderd of dollars, problems rapidly increase. No deliveries, bend pins on
connectors, refurbished parts, preprogrammed OTP parts, etc.

Occasionally, I still purchase the broker way, but only for parts that are very difficult to get in smaller quantity, or
when there's an unforseen superleadtime on the official channels which would kill my production and subsequent
delivieries for a long time.

[HardBoot]

Buying large volume makes big distributors look more appealing, but when I need a few of this and that for trying out something, they're hopeless.

There's good large quantity Chinese sellers, but when buying really large the different in cost isn't as big. China's focus really in on making things in the country, not exporting for manufacture elsewhere, so they're not that big on parts distribution for major stuff.

[szhighstar]

it depends on your lucky, frankly say there are some fake parts in China, however more and more parts are genuine in China, I am enginner in China, I know these things, more factoies in China very take care of quality issue, especial export goods, if happens quality issue, it is very trouble for China factories, boss maybe loses much money for any complaint, profite is becaming little and  little now.
If you only see price and do not think quality, it is other thing. we do not buy these fake parts normally, it is very dangerous for R&D item.
However some parts from China have good quality, even if these parts copy some famous brands,these parts have their brand.

[chickenHeadKnob]

it depends on your lucky, frankly say there are some fake parts in China, however more and more parts are genuine in China, I am enginner in China, I know these things, more factoies in China very take care of quality issue, especial export goods, if happens quality issue, it is very trouble for China factories, boss maybe loses much money for any complaint, profite is becaming little and  little now.
If you only see price and do not think quality, it is other thing. we do not buy these fake parts normally, it is very dangerous for R&D item.
However some parts from China have good quality, even if these parts copy some famous brands,these parts have their brand.

Hello szhighstar, thank you for giving us some insight from the chinese side. I am just getting involved with ebikes, as you probably know very big in china and most of the components in BLDC motor controllers seem to be fake (shanzi?). I am talking about the higher value parts like mosfets. International Rectifier (IR) hexfets are popular but we did some tests and the chinese controllers fets are inferior to real IR fets on a number of parameters, rds on and a whole bunch of others, forgive me I am a software guy. The labels/packages are getting more and more authentic looking but a fet that suffers a failure in the field is very expensive. It wipes out any savings on the purchase side. It is worse if the failures are intermittent because the parts just make the grade sometimes.