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by jstanley 981 days ago
Personally I avoid buying direct from China whenever possible because I want parts quickly so that I can make progress on the project.

The cheapest solenoids I can see on Amazon Prime are about £5 each. 24 of those would be over £100.

Plus, the stated goal of the project is to learn a bit more about electromagnetism, so making your own solenoids is not even a bad idea.

3 comments

> to learn a bit more about electromagnetism, so making your own solenoids is not even a bad idea

You can learn by making one. Making 24 is super annoying IMHO.

(Also, if you want to try, ready-made sewing machine bobbins are a good alternative to 3D-printing your own solenoid body.)

And about the rest of your comment: one approach would be to buy one solenoid from Amazon, to let you do experiments and set up the whole machine, while waiting for the rest of the goods to arrive from China.

I had most of my Aliexpress orders arrive in something like 10 days. Is it much slower in the UK?
You have to make sure you get the fast shipping else it takes a month.
That's almost 2 weeks! Amazon Prime comes the next day.
I guess I'm just not as spoiled ¯\_(ツ)_/¯

I'm used to my online purchases taking time. The closest thing we have to Amazon is Ozon, it's 1-2 days if you buy something that's already in a warehouse in your city (i.e. if you're lucky) and several more days if it's not.

why would you buy solenoids from amazon instead of an actual electronics distributor?
I pretty much always buy components from either Amazon or eBay. Is that unusual?

I just looked on Farnell and the cheapest solenoids that I could find in stock have a weird housing (and they're £6.38 each which is already more than Amazon), the cheapest sensible ones that are in stock are £12 each, which is way more expensive than Amazon, plus you have to pay VAT and postage on top, plus you have to faff around with their enterprisey order form, compared to one or two clicks on Amazon.

Yes, it's unusual for professionals, just fine for hobbiests.

Because of reliability, etc.

For the same reason you wouldn't order your ingredients for a professional Michelin starred restaurant from Amazon.

I've almost never found Amazon cheaper either. The sellers on Amazon are almost always not the original manufacturer, they're usually FOB folks who are just buying big boxes of things and then selling them individually.

You're almost always better served to swim upstream and get things from the manufacturer, or from reputable electronics distributors like digikey, Farnell, mouser, jameco,etc. A quick search at some of those and I'm finding suitable solenoids at $2-5

Sometimes, because you Just Don't Care™ about any particular manufacturer spec, and you're unwilling to pay egregious Digikey/Mouser markup times 24.
It's not that Digikey or mouser is taking those inexpensive overseas solenoids and marking them up.

The products on mouser and digikey are from reputable industrial component manufacturers. They have warranties and datasheets, support from the mfg, traceability and trustability, etc.

They're simply different products. You can't compare a quality made product from a quality supplier and manufacturer to cheap crap you buy on amazon

It's both. The product on Digikey is quantifiably better in many regards. It's also got a price premium on top of the increased price from the OEM. You have to pay Digikey enough to make it worth their while to ship 1 of something to you.
And if you value your wn time above even minimum wage it's a trade well worth taking.