Author Topic: What kind of quality to expect for chinese "Precision" tools and stuff  (Read 4357 times)

Offline PekkaNF

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You get what you pay for. I know. Sometimes you get more and sometimes less.

But when you buy a cheap tool or mesument contraption how much "accuracy" it is reeasonable to expect?

I would think that you have still right to stick to spec numbers, least to close to them...some roughness, lack of secondary functionality and finess is fine to me. What is fair and what is unreasonable?

Reason is that I bought this one:
http://www.banggood.com/Toolmaker-Precision-Micro-Adjustable-Angle-Block-Milling-Setup-p-1057240.html


Dent, ok it is annoying, but not functional...I don't care too much, but it is annoying because the piece had a dent (or it was sliced from bar and it was at very end....) and ground after it.

More serious to me is that the shor end is not straight in either plane. Error is about 0,1 mm.

I haven't checked it all around, height looks about fine and least zero angle fiducial line is at zero.

But if general description lets you know that the angle block is finished within 0,01 mm, is 0,1 mm reasonable at other direction?

Basically I'm asking for the price am I expecting too much?

Pekka

Offline nrml

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #1 on: September 22, 2016, 02:55:59 PM »
I would ask for a refund. The Chinese auction sites are usually very good about refunding your money if you show clear photographic evidence that the product is defective.

Offline sparky961

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #2 on: September 22, 2016, 08:05:37 PM »
So, this may be counter intuitive, but is it reasonable to expect that surface to be accurately perpendicular to the other?  Is it part of the specification?  Of course, you do expect that, as would I, but it doesn't necessarily make for an unusable or even "defective" tool.  I suppose if you wanted to clamp it on the small end, it wouldn't work well.  But it is much more likely that you're using the bottom as a reference.  And don't even begin to think about using the scale for any kind of accurate work.  You'd need to set the angle with something more precise anyway.

It makes me think of 1-2-3 blocks.  I'm not sure how square the high quality ones are, but they aren't really meant to be.  They are most often very accurate in size and parallelism, which is exactly as they should be.  But I could probably get something more square by eye than by using a 1-2-3 block.  Go for it, check out your cheap set...

It wouldn't take much on a surface grinder, if you had access to one, to finish off the Chinese "kit" tool and grind the surfaces in properly.

Think like a machinist, not a simple consumer.

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #3 on: September 23, 2016, 02:13:04 AM »
Thank you for the answers.

That is part of the problem. How do you read description (spesification) that is not very good:

****
Toolmaker Precision Micro Adjustable Angle Block Milling Setup

Specification:
Material: steel, surface hardened to HRC58-62 °, nickel plated.
Dimensions (LxWxH) 75x25x32 MM
Angular Precision 10 'On Readable Nonius
Micro Adjustable 0 ° To 60 ° With Stop Scr

Uses: In the milling machine, planer, drill press with adjustable angle grinder and regulations on the knife, crossed with other fixtures or clamping the workpiece after the workpiece processing, such as processing slope, slant-hole drilling and the like.
Nickel plated, rust parallelism and verticality precision grinding of each working face to 0.01mm.
It can be a cursor indicates stepless tilt adjustment angle, and then be secured with screws, used to create a variety of fixed angle processing, testing of workpieces.

****

I'm tempted to claim that "rust is not parallel to verticality to 0,01 mm". :lol:

The example of 1-2-3 block is good. They would be completely useless if parallelism would be bad. And pretty near useless if they were not square.

With this V-bloc, the V- must be very true to all working planes and bottom surface. That is the must and I should have a look at it, but it looks fine.

However I don't think it would be reasonable to expect external working surfaces to be accurate to stated number (0,01 mm) unless otherwise mentioned. Bit like parallels....their opposite surfaces has to be parallel to great degree, ends have very little consequence, but you don't expect beaver bites there either.

My analogy would be here try square. What about if you think that you buy a flat square and one side is beveled unevenly? I'm not talking here hair line, but the case that other side of the square is square and other not.

Re. scales...I feel that scales must have more than entertaining values. There are bunch of DIN standards that pretty much states what accuracy scales should be each type of tool and accuracy glass. Here no DIN number were mentioned, but there is this statement "Angular Precision 10 'On Readable Nonius". I agree, it is not for measurement, but that should help the set up.

Offline SwarfnStuff

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #4 on: September 23, 2016, 03:20:26 AM »
Pekka, I think an email to them with photos is well within your rights. Whether you ask for a refund or replacement would be a matter of choice.
     Interestingly, I toddled off to fleabay and found many there ranging from $20 to $96 AUD and they all seem to be using the same product description claiming 10' accuracy. If my thinking and rusty math is correct (probably not) that is 0.166deg accuracy.
    The tool also is supposed to be "precision", surely that implies a lack of dings, dents and poor workmanship so ask them to rectify.
    As has been said, you could make it useful if milled flat and square to remove the dent, assuming there is enough material to do so. Refund plus a usable tool with a bit of work?
Back to my search, the $96 AUD one claims 10" accuracy so price and accuracy works there. Plus, it comes in a box. See link.
http://www.ebay.com.au/itm/4-x-1-3-16-Precision-ANGLE-BLOCK-Adjustable-Toolmaker-Gauge-0-60-Degree-/370841136414?hash=item5657daad1e:g:w~oAAOxyLchRx2FZ
  Another at $35AUD had this note that has me confused but I post it for interest and pondering exercise,
"Note:     Please allow 1-5mm errors due to manual measurement."



John B
Converting good metal into swarf sometimes ending up with something useful. ;-)

Offline Lew_Merrick_PE

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #5 on: September 23, 2016, 01:14:28 PM »
I am sure that there have to be good shops -- even in China.  I have seen Chinese-made tools if good quality (granted, few and far between).  My personal experience with having work (for my customers) done in China bodes differently.  After having waited more than 24 weeks for Chinese-made parts (that I could have had made locally in 3-10 days for much less $$$), neither material nor dimensions were even close to the specifications!  My "client" on this was Microsoft who complained that my specifications were too technical (ASTM, ANSI, and the like).

When I go to Harbor Freight to purchase measuring tools for clients, I take a set of gauge blocks to test them before putting $$$ on the table.  I often go through 6-8 "devices" before finding one that is accurate and repeatable.

Offline Manxmodder

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #6 on: September 23, 2016, 02:37:39 PM »
Lew,you're absolutely right to say "there have to be some good shops" There are many manufacturers throughout China who are extremely capable of producing top quality stuff.

As part of my work for a UK company I visited the annual Shanghai Tool Expo to sound out manufacturers we could do reliable business with. I was often very impressed with the standard of manufacturing machinery and quality control systems when I later followed up by visiting some of the manufacturing companies we had selected to do business with after the expo.....OZ.
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Offline NeoTech

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #7 on: September 23, 2016, 04:50:30 PM »
Usually buys tools from here; http://www.ctctools.biz/
Its run by a dutch guy living in Hong Kong - always been good tools. But well still chinese tho.
Machinery: Optimum D320x920, Optimum BF20L, Aciera F3. -- I have not failed. I've just found 10,000 ways that won't work. http://www.roughedge.se/blogg/

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #8 on: September 24, 2016, 10:11:53 AM »
Usually buys tools from here; http://www.ctctools.biz/
Its run by a dutch guy living in Hong Kong - always been good tools. But well still chinese tho.

I have been getting ER collets from there years, but haven't looked this sorts of stuff from there before...and they seem to have the same.
http://www.ctctools.biz/toolmakers-microadjustable-angleblock-b02/

Pekka

Offline NeoTech

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looks the same perhaps. different quality control tho.

Sent from my A0001 using Tapatalk

Machinery: Optimum D320x920, Optimum BF20L, Aciera F3. -- I have not failed. I've just found 10,000 ways that won't work. http://www.roughedge.se/blogg/

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #10 on: September 26, 2016, 02:13:07 PM »
Now I have mailed them three times explaining best I can. Their stand is "About the item, the manufacturer said that it is acceptable, it is not the quality problem, and still good for using to the measuring job. Hope your kindly understanding. Thank you. "

I feel pretty stongly that it is very much quality problem. I'm not saying it is useless, I'm saying it has a defect.

I'm thinking of ordering a new one from CTC or somewhere else and avoid buying from them.

Pekka

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #11 on: October 07, 2016, 05:47:52 AM »
Well fool me six times :lol:

Decided to give up with that company and their products. Problem is that I have few more on the slow boat.

Yesterday I got ER20 holder that I put on the test right way. I ordered parallel shank 20 mm ER20 holder, nut, chuck key and three collets.

The nut key did not fit into the nut! I normally would just bin it, but this is the mini nut, with a rather special key. Doubt if that zink? cast key would be any good anyways, no big deal.

BUT looks like the tightening nut or thread on the shaft is 0,1 mm wonky! Tightened some solid carbide drills into the chuck and all were off least 0,03 mm, right on the collet.

Now I know where not to buy. I'm going to measure all parts carefully and then contact them.

Should I use PayPal dispute or what would work? I don't like long winded e-mail exhange, where the other end has no idea how accurate their 0,01 mm "precission" holders should be.

Pekka

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #12 on: October 08, 2016, 03:24:56 AM »
I'm measuring some ER shanks and collets. CTC stuff seems to have TIR allways between 0,01 - 0,02 mm range. I have never measured worse and not regualary better. These I measure just cleaning parts and putting them together.

On the other had eBay/banggood seems to be at it's best (after much fiddling) close to 0,02 mm and worst so far 0,08 mm!

I'm including the pictures of the method that provides most accurate and repeatable results, I could come up with. I tonly works well on cylindrical shanks.

Shanks seem to be often a little under size, tapering a little (about 0,01 mm /100 mm) and one was slightly trilobular!

Most challenging to measure was my latest ER20/20 mm parallel shank and three collets I got.
8 mm collet, best 0,02 mm TIR
10 mm collet regularry 0,04 mm TIR
12 mm collet 0,06 -0,08 TIR

Included Nut key did not fit into the nut!

Pekka

Offline chipenter

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #13 on: October 08, 2016, 01:47:32 PM »
I bought a set of ER16 collets from China , and they had buurs on the slits a clean up with a diamond needle file brought the errors fight down .
Jeff

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #14 on: October 08, 2016, 02:07:46 PM »
Thanks. I noticed the burr too, but it does not stop there. Any problems with threads? Or nut taper being rough or excentric?

CTC stuff has worked out of the box, not up to real western standards, but very decent for the price.

Three examples I have ordered from china mainland have had more burrs, thread hasnot been that great and nuts have had issues.

Pekka

Offline chipenter

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #15 on: October 09, 2016, 02:48:23 AM »
I bought two parralel ER16 collet chucks from ARC no problems with them , one morse taper one chuck direct from China not as good but usable , the nut had more play and mutch slacker .
Jeff

Offline CrazyModder

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #16 on: October 09, 2016, 11:24:07 AM »
I won't judge whether there are good shops somewhere in China.

But it *is* highly likely to get junk when buying overseas for their small prices. There surely are some exceptions; for example electronic parts (µCs, transistors and such). If I buy them local, the only difference is whether my local vendor imported it from China or I did so myself. I expect no difference in quality there. It starts to get wobbly when buying bigger electronic items (like whole boards with a few components). I know of one case where they ran out of a specific kind of capacitor and just substituted another one; the item then worked for a few minutes and then stopped. Thousands were produced, and good luck getting a refund for a 2€ item (including postage...).

Back to the question at hand: while there certainly are exact items to be found somewhere, I would not bother to invest *any* kind of anger or otherwise energy into the process. As you also found out, their customer support is more likely to tell you "it worked for everyone else as well, must be your fault". What do they have to lose? It's not that you will drag them in front of some court. Of course, the locally bought item would likely have been produced in China as well, but with a bit of luck, your local vendor has done some QA, or will at least help you with a refund/exchange if you so inquire.

So, you trade the often absurdly low prices for a certain element of luck.

Offline sparky961

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #17 on: October 09, 2016, 02:26:59 PM »
I consider every insanely cheap overseas purchase to be a "kit" item.  It will likely need cleaning, grinding, filing, polishing, or maybe throwing out half the parts and remaking them. ;)

Anything I want to be able to trust in its use and accuracy I research well before hand and try to buy at somewhere around the 60-70% price range from the short list.  Usually the stuff near the top is way higher quality than I'll ever need, though I've splurged from time to time and rarely been disappointed.

Most of us here who have undertaken any project with difficult pieces or many that must fit together in a precision way should really appreciate how much time goes into making things.  Even with mass production, the time is still there, just spread out amongst the few thousand (or add some zeros) pieces they make.

I don't have a problem paying for quality, within reasonable limits of my budget and intended use.  But I'm well-aware that a brand name and high price don't guarantee it.  It does, usually, give you recourse if you aren't completely satisfied - which takes a lot more considering the price you paid.

Offline PK

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #18 on: October 09, 2016, 06:23:50 PM »
I consider every insanely cheap overseas purchase to be a "kit" item.  It will likely need cleaning, grinding, filing, polishing, or maybe throwing out half the parts and remaking them. ;)

I think this is the right approach. I've bought everything from electronics components to large CNC machines out of China.  Set your expectations and you'll get a result you are happy with.

I'll add one point. The Chinese are certainly capable of producing good quality goods. You just have to ask them to do it. 
If you don't ask for quality, they will (rightly) assume that you are buying from China because you want the cheapest product.

I say this on the back of spending about $100K per year in China, not millions, but enough to get a good feel for it.

The best example I can think of is our stickers. We get the stickers that go onto our products from China. It took two orders that we weren't happy with to convince them that we wanted the fancy ink and 3M brand adhesive. Since then we haven't looked back.
The stickers are the thing that turns our plastic boxes into merchantable product, so it's vital they be of the best quality and they really are.



Offline ieezitin

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #19 on: October 09, 2016, 08:23:37 PM »
you get what you pay for. expectations on trying the cheap method will always produce low results. cheap tools have a place as other people have mentioned they can be massaged into place but time is an asset, I have both, i use both depending on what i am doing.

I have a set of Helios vernier calipers made in Germany from 1979 and used every day give or take they are still dead on today 37 years of service that price paid then is worth every penny,irony is they were a gift.

Anthony.
If you cant fix it, get another hobby.

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #20 on: October 10, 2016, 04:34:29 PM »
How do you know and tell that you are paying for quality, when you buy consumer quantity?

I'll try to avoid lowest and highest price on "same" product. But it is hard to choose over "same" product when large amount of sellers use same picture and same spesification. And all chinese tool looking objects seem to have words like "Precision" etc.

I don't have more than spesification to go for. If something says in effect of precision 0,01 mm, I have right to expect if I measure it right. OK, I allow chinese to lie a little...they seem to say 0,01 mm when they say 0,02 mm TIR, but I would not accept 0,08 mm TIR. on ER collet chuck small expensive four flute endmill would in an effect of a fancy miniature fly cutter that needs to have adjusted to 25% of feed.

So, I bought four collet chucks from three sources. One is abysmally bad, one is really very nice and near advertised accuracy and two the normal quality you expect. The one that sucks was nowhere cheapest!

OK, normal visdom is to buy from EU vendor. I can tell right away one UK merchant that is somewhat more expensive, but usually deliveres pretty much what you are let to understand. Yhen again there is one UK and one german shop I have ordered stuff twice and always have been disapointed. Same or even lover quality chinese stuff, but with much inflated prices.

Some tools it is just down to availability and delivery time. If I want to order ONE ER shank or other 20-40 EUR/GBP tool and I need to wait nearly week and pay 20€ postage...or have that from Germany in three days and pay 5-7€....or free shipping, but 2-3 weeks from china...UK does it's best to deter me.

However, just ordered some stuf from ARC, total 240€ I hope that ER20 holder ir worth of 20€!

Sometimes I really would like to buy real western tools and sometimes I can. Sometimes it really has been that difficult to buy quality tools that in discust you click one from eBay and wait the "surprice".

Pekka

Offline Manxmodder

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #21 on: October 10, 2016, 05:03:00 PM »
I'd say the answer to consistent quality comes down to word of mouth and looking at which suppliers others recommend. For example,I have purchased a number of things such as precision vices,collet chucks and blocks from Arceurotrade and never been unhappy with the quality of any item. I think this may be down to them setting a certain quality control specification from the manufacturer and likely paying a bit more to maintain those standards. I have also been pleasantly surprised with the quality of some things I took a gamble on when ordering directly from Chinese internet suppliers.  I've had a good number of carbide burrs direct from China that have proved very good quality for small outlay......OZ.
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Offline PK

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #22 on: October 10, 2016, 05:53:20 PM »
How do you know and tell that you are paying for quality, when you buy consumer quantity?

Good point, you have no control for small purchases. For larger purchases, like a machine or some sorts, you often end up chatting for some time before the deal is done. This is where you get to ask for the upgrades..

PK

Offline ieezitin

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #23 on: October 10, 2016, 06:17:45 PM »
Pekka

I feel your pain and thoroughly understand your dilemma.

Personally i don't trust the Chinese claims for the quality of there products that they clearly advertise because majority Chinese companies spend too much time thinking about what they are making and not how to manufacture it. 


But on the other hand some stuff is worth every penny you spend on it because the vendor flogging it in what ever country has strict demands about quality and has a handle on the Chinese manufacturing culture, contrary to popular belief Iphones are not made in China they only  assemble them there, Apple gives them the fool proof pieces of the puzzle made elsewhere and bingo an Iphone they are not trusted to manufacture it but just snap it together.   

I believe Manxmodder hit the nail on the head word of mouth from others is the key to buying valued semi quality items from China and the vendors who sell the products sadly that means someone has to take a hit with a bad experience for others to benefit that's the beauty of this forum we have to share the good and bad.

Anthony.
If you cant fix it, get another hobby.

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #24 on: October 16, 2016, 05:24:23 AM »
So what the Fedex brought in. Spent 10*more on ARC than on latest china shopping. I expect clearly better value.

Not surpricing the almost identical ER chuck was whole lot nices, I don't care much of the looks, but finish on the mating surfaces must be good enoug. Still it is not quite up to DIN stndard, but miles closer than the Bangood one.

Pekka

Offline lesterhawksby

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #25 on: October 17, 2016, 07:15:07 AM »
I would recommend checking if the ARC nut, on its own, is enough to sort out your ER collet problem. I had something similar - disappointing ER collet accuracy, replaced nut with a better one (ARC, not a real posh'un), same socket, same collet, problems went away. I have formed the impression that ER is sensitive to a bad nut.

I have a slight suspicion some categories (not all) on Banggood are the "seconds" that didn't go to named importers... even if you get the same item there are higher odds it's iffy. Other things are absolutely fine. Definitely not consistent.

Hope that ARC haul is all good stuff :-)

Offline tom osselton

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #26 on: October 17, 2016, 02:51:54 PM »
They probably are seconds I have never used them but the name says it " banged good "  but not  everyone can afford top notch components for something they will not use  that often.

Offline DavidA

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #27 on: October 22, 2016, 07:23:29 PM »
Just to add a bit.

Today I used for the first time my Chinese boring read.

Not a top of the range item by any standard, but looked as if it would be ok for the kind of stuff I do.

But I was a bit disappointed by the lack of detail to a couple of simple things.

The head came with half a dozen brazed-on carbide tipped tools.

I fitted the appropriate tool and proceeded to bore out a socket for a hex bolt head in a piece of Dural.

No real dramas, but when I came to remove the tool from the head it wouldn't come out.

Eventually I managed to tease it free and found a couple of marks on the shaft that had been snagging and that was what had prevented it coming out.

Further investigation revealed that the small grub screws that hold the tool in the head had conical tips.  And it was this cone that had dug into the tool and raised a couple of burrs.

Also the Allen keys that come with the kit are soft.
I have only used them for this one job and they are already rounded over on the corners. Virtually useless.

Still, you pays your money and you takes your chances.

The head is usable. But the screw tips need attention and the damage has to be removed from the cutter shaft.
And, of course, decent Allen keys obtained.

Dave.

Offline sparky961

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #28 on: October 23, 2016, 12:30:33 AM »
... it was this cone that had dug into the tool and raised a couple of burrs.

Also the Allen keys that come with the kit are soft.
I have only used them for this one job and they are already rounded over on the corners. Virtually useless.

The head is usable. But the screw tips need attention and the damage has to be removed from the cutter shaft.
And, of course, decent Allen keys obtained.

Dave.
[/quote]

May I suggest milling or grinding a small flat on the shaft?

Also, don't stop at tossing out the allen keys. Replace the set screws with high quality ones before you're cursing one with a rounded out head.

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #29 on: October 23, 2016, 02:51:59 AM »
I got friday two same items: ER25/MT3 shanks, cleaned them up and assembled with a good collet and mesured silder steel rod. Put them on surface plate and measured: Other was 0,06 mm and the other 0,8 mm TIR. Paid 12€ per piece....so, other one is usefull for drilling and other uses I got it.

Other one is a plastic bucket of "trash tools" waiting insipration to check further or used for something that accuracy is on the list.

To the booring head: I would chance allso all screws and specially the set screw. Had one breaking in the hole and it was a proverbial to move.

Offline PekkaNF

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Re: What kind of quality to expect for chinese "Precision" tools and stuff
« Reply #30 on: October 23, 2016, 06:41:06 AM »
Soo...turned better ER25/MT3 shoulder down (because my mill has a slot at the end of spindle for dog. OK. for normal spiral drills.

But sometimes you'll get a nice surprice. Years ago I bought one long single tip MT3 boring bar from ARC. It seems to unbelievably straight for such a tool. 0,02 mm TIR near tip! In a pinch I could use it as a MT test bar. I never used it first while waiting for it I rushed to work with a boring head and later didn't have faith in that bit, but it is standard 8*8mm bit. Should get one.

My setup for MT taper shanks, I found one MT/MT adapter that has female taper very concentric with outer shell.

Pekka