how to test a chinese part versus name brand

[MartinR]

Originally Posted by Nicholson58

While we are all gathered together perhaps someone knows the answer to this related.

I have Harken Air Blocks with bearings turned to powder. When we left the boat in Antigua for the summer I thought it would be simple to find replacement rollers. Harken apparently has two sizes. I can’t find specifics on their site and they do not respond to inquiries.

There appear to be both rollers and balls. Zoom in. Rollers look OK but the balls are goners.

The rollers take the load and are made out of Torlon, tough stuff. Expensive to replace. The balls are some kind of Delrin and take sideways load. Very cheap to replace. I have renovated a lot of Harken blocks and all Torlon rollers were in good shape, while the sun had killed the Delrin balls.

[ArmyDaveNY]

Originally Posted by Seapig

I have recently found myself in need of some polyoxymethylene ball bearings. Harkin sells them for about 98 cents per bearing, Lewmar for about 1.25 per bearing. A company in Tennessee sells them for about 15 cents and a Chinese retailer sells them for $3 per thousand.

How many bearings do you need? IF you are talking just a dozen or so, buy the name brand and have peace of mind. For ten or twenty dollars, the difference isn't worth worrying about. IF you are talking hundreds, then it might make a difference.

[thinwater]

Originally Posted by Seapig

Thinwater- I never thought of McMaster Carr they didn't come up in the google search. I will remember them for next time. I ended up ordering from BC Precision Bearings in Tennessee. They are a listed dealer for several U.S. and Japanese bearing manufacturers. According to the person I spoke with all Delrin, Acetal and Torlon bearings come from China.



On this general note-- Is there a place in this forum or any other forum for that matter that aggregates suggestions such as that made by Thinwater. He got his bearings from McMaster-Carr they worked well and they are a twentieth the price of the Marine source. One can of course search and read a bunch of posts but it would be nice if there was a "boat hacks" type of list somewhere.

McMaster Carr is not as cheap as Amazon can be, but they have a LONG reputation in industry for industrial (not Home Depot) quality and 1-2 day delivery of everything they list, which is a LOT. Plant and factory guys love that combination when something breaks. They don't have the time to hunt around, and they know the quality will be good. A good source for odd fasteners, materials (metals, plastics, composites), small pipe fittings of odd materials, tools, and anything else that is not purely marine. Often they are better than other sources just because they are so fast. Before Amazon they were a godsend for industry.

[trifan]

Originally Posted by Seapig

Before this develops into mud slinging, let us remember that everyone is entitled to an opinion. You may think it is uninformed or if it agrees with you than it is obviously well reasoned but it is only an opinion.

To that end can we please stick to helping each other find working solutions to the very expensive and difficult proposition of owning a boat.

thank you

HEAR, HEAR! I was going to say something like opinions are like a_holes, everyone has one and almost all of them stink, but the Seapig is more adroit than I.



Back when Japan was recovering from WWII their stuff was crap, too but they eventually got that sorted out, got expensive, then outsourced to Taiwan. Then they repeated the cycle and manufacturing went to China. I wonder what happens when they get good and expensive?


I, too, am often disheartened by how our markets have been willingly ceded to China as they (like Pinky and the Brain) continue their goal of world domination. I realize, however, that in the great totem pole of political influence, I am down there at the bottom next to whale poop so all I have is opinions (and observations). Being cynical only works if you can smile at the same time.



FWIW, I recently shopped for some 1/4" galvanized steel 7x19 cable and found prices below US$1.00/ft from many vendors and prices above US$1.50/ft and up from some others. The lower ones were all from China, the mid-range ones were from S. Korea and the others were made in USA. It cost me 4x the price of the Chinese cable to buy American made but I will sleep easier knowing that it is 10x less likely to fail. YMMV

[P3sailor]

I'm totally with you on that. I just paid $300 for a coffee maker (made in the Netherlands) just so I wouldn't get one made in china, just did something similar with some 10"saw blades. Dewalts made in china and found some made in Thailand so I purchased those. The more we purchase from that country the more we enable them.

[wingssail]

Originally Posted by MartinR

The rollers take the load and are made out of Torlon, tough stuff. Expensive to replace. The balls are some kind of Delrin and take sideways load. Very cheap to replace. I have renovated a lot of Harken blocks and all Torlon rollers were in good shape, while the sun had killed the Delrin balls.

Here are three halyard sheaves I removed from my mast head. The center one in this photo is the main halyard sheave (it is roughly 4.5 inches in diameter).

I had been having trouble with that halyard going across the Indian Ocean. I was everlastingly happy that the mainsail came down. I removed the mast mostly to service these sheaves. Note that the Torlon bearings were gone. The Delrin balls were fine.

These narrow sheaves required very short Torlon rollers, and they were only available in that dimension from Harken. The told me they had only 500 left in stock. I said I'd take them all. Then they told me they were $5 each. I took 45.

Later I found a local South African supplier who sold Torlon rod and I could have cut my own rollers.

[Tellie]

Originally Posted by Seapig

Before this develops into mud slinging, let us remember that everyone is entitled to an opinion. You may think it is uninformed or if it agrees with you than it is obviously well reasoned but it is only an opinion.


To that end can we please stick to helping each other find working solutions to the very expensive and difficult proposition of owning a boat.


thank you

Thank you. I'm afraid the China thing would be worse than a combined anchor/gun thread right now.

[goboatingnow]

Originally Posted by MartinR

The rollers take the load and are made out of Torlon, tough stuff. Expensive to replace. The balls are some kind of Delrin and take sideways load. Very cheap to replace. I have renovated a lot of Harken blocks and all Torlon rollers were in good shape, while the sun had killed the Delrin balls.

Torlon being a polyamide-imide engineering plastic versus Delrin which is an acetal polymer. Chalk and cheese

[goboatingnow]

Originally Posted by Dave_S

I try not to buy anything from China. Sadly it's not always possible. It's usually poor quality and I don't like the politics.



The only thing that has lasted that was made in China is covid.

You are entitled to your opinions but you are not entitled to belittle a whole nation

For example I’m of the opinion all American cars are crap. But I should keep that opinion to myself. !

[Nyaminyami]

Originally Posted by Alan Mighty

Good to see a bloke stand up for principle.

Toss out the tea and ketchup. Give oranges, tangerine/mandarin oranges, and pomelos the heave ho. Send all those weirdo leafy green varieties of the cabbage group straight to the bin.

Toss out the paper, moveable type, and gunpowder.

And be serious: toss out sail battens, lazy jacks, the whole idea of bulkheads and that of sternpost rudders, too. End the junk rig (and all the ideas that came with it, including the afore-said battens and lazy jacks).

Away with those ideas of yin and yang. Don't let silk get near you.

Steer right away from artesian wells. Outlaw wheelbarrows. Spurn the idea of inoculation.

And porcelain! Jeez, some fools call it china or chinaware!

Tinted spectacles? Chinese invention to hide where a judge was looking.

Bureaucracy too - chuck it out along with the notion of exams for entry to the civil service. Norman King Roger of Sicily was the mug who introduced those poisonous ideas from China. Silly blighter commissioned Muslim scholars to write a compendium of all knowledge, unthinkingly opening the way for the idea of experts in government maintaining written files and following rules of procedure. Shocking!

Into the dumper go all the ideas of Confucius and small, ethical government.

Pity our friends in Nippon, Republican Korea, and Viet Nam. They'll have to give up some fraction of their written languages.

The local florist is going to be in trouble - it's going to take a while to sort out the exact origin of those chrysanthemums, peonies, hibiscus rosa-sinensis (jolly name gives itself away!), camellias, plum blossoms, and azaleas.

Same with decorative knots, just not needed.

As for stir frying in a wok! No more. Make it a rule: deep fry is good, boiling or stewing better. None of this piddly splash of oil in a curved pot. Out!

We might need a book burning, but I hear the precedent for that might be Chinese too.

:
Tha nx::thumb

How mighty thou Art! Awesome riposte.
But regrettably there are many of our brothers and sisters who are happy with the simple answers and the one-liners of deluded autocrats.
Fair winds and calm seas.

[Simon.Sails]

Having lived and worked in China I can certainly understand the reluctance to order from an unknown Chinese factory. And these products tend to look good at first as well. But honestly do you want the hassle of frequent replacements of something that's fairly cheap? I much prefer the vast majority of components of my boat to be of sufficiently high quality that I don't have to think about them for a few years.

[goboatingnow]

Originally Posted by Simon.Sails

Having lived and worked in China I can certainly understand the reluctance to order from an unknown Chinese factory. And these products tend to look good at first as well. But honestly do you want the hassle of frequent replacements of something that's fairly cheap? I much prefer the vast majority of components of my boat to be of sufficiently high quality that I don't have to think about them for a few years.

Unfortunately the relationship between price and quality isn’t at all linear. Dealer and importer markups etc all have nothing to with quality.

A Toyota is half the price of a BMW. But the reliability is similar or better.

It require expert knowledge to separate quality from price

[jimbunyard]

Originally Posted by Seapig

I have recently found myself in need of some polyoxymethylene ball bearings. Harkin sells them for about 98 cents per bearing, Lewmar for about 1.25 per bearing. A company in Tennessee sells them for about 15 cents and a Chinese retailer sells them for $3 per thousand.


I would be very surprised if Lewmar or Harkin didn't get their bearings from a Chinese manufacturer but I of course have no proof. For $3 I am thinking of ordering a thousand from China and testing them to see how they compare. If they are crap I can use them as sling shot ammunition.


The question.
How could one go about comparing these items without a bunch of sophisticated equipment?


As always thank you for your thoughts
SP

Well, if it's OK to have an opinion, I think China-bashing is at best ignorant. (but mostly racist and stupid)


But to the most interesting question, "How could one go about comparing these items without a bunch of sophisticated equipment?", for 3 bucks, if you need more that a couple of dozen, I'd go with the bright Red ones, and test them against a couple of the fine Yankee ones with these 2 super-sophisticated tools. A hammer and some fine sandpaper.

If they turn out just as good, or better, than the originals, you could sell the rest to your friends and neighbors...

[Simon.Sails]

Originally Posted by goboatingnow

Unfortunately the relationship between price and quality isn’t at all linear. Dealer and importer markups etc all have nothing to with quality.

A Toyota is half the price of a BMW. But the reliability is similar or better.

It require expert knowledge to separate quality from price

I didn't suggest that either. The difference is QC by a reputable party or not. That will be reflected in the price of course, but nobody suggests a linear relationship.

[Dave_S]

Originally Posted by Dave_S

I try not to buy anything from China. Sadly it's not always possible. It's usually poor quality and I don't like the politics.

The only thing that has lasted that was made in China is covid.

What the hell did I say that bought out the idiots ?