Outstandingly good eBay seller! - Page 1
Forum section: electronics / general

author: RogerRowland
author_rank: Regular Contributor
timestamp: December 10, 2016, 11:53:27 am
content: Having had plenty of eBay buying experience, I have to report the outstandingly good customer service I received from one particular seller.I ordered 4 x NEMA 14 stepper motors for £16 inc. postage:http://www.ebay.co.uk/itm/172420507897Unfortunately, only 3 arrived, in a bag that was obviously used during shipment to re-pack after some kind of "mishap". On further inspection, I saw that instead of the NEMA 14's I'd ordered, these were actually NEMA 17 motors - bigger and more powerful, and actually on sale elsewhere - not eBay - for £22 a piece, although this seller will give you 4 for that price. They had obvious signs of being dropped at some point, presumably when they fell out of the original package. Some pics attached.Anyway, after reporting this to the seller,and attaching photos etc., his fast, polite and generous response was to say - ok, this is not how we would have packed them, it's the shippers fault, you can keep the 3 NEMA 17 motors and I'll send your 4 NEMA 14's by First Class post. They arrived this morning, very securely packaged and in perfect condition. The whole thing, from original order to final receipt only took 6 days.So, I'm not a penny out of pocket, the seller has (or will) hopefully recoup losses from the shipper and I also have 3 "free" NEMA 17 motors in addition to what I'd ordered.After spending 48 days getting a £1.04 refund for a no-show item from another - unnamed - eBay seller, this was a hugely impressive response and I can only give the guy my thanks and praise and try to publicise his response as widely as possible. If you're in the UK in particular, and are in the need of anything that this guy sells, I would highly recommend giving him a try. I have no association with the seller, just a very very happy customer.The first two pics are the damaged shipment and the last pic is the package I just opened.

author: ataradov
author_rank: Super Contributor
timestamp: December 10, 2016, 07:22:25 pm
content: No matter how much I try every time I need a stepper motor, I still get the best pricing fromhttp://www.omc-stepperonline.com/and their packing is exceptional.

author: ez24
author_rank: Super Contributor
timestamp: December 10, 2016, 07:47:44 pm
content: Quote from: ataradov on December 10, 2016, 07:22:25 pmataradov I have a question that comes to me every once in awhile. A long time ago I rode in a golf cart up a steep hill. It went slow but made it. I looked at the motor and it was big (3 hp seems to come to mind). I do not know the volts, 36 or 48 ?Sometimes I wonder what kind of 4 stepper motors (one for each wheel) could equal the power of a golf cart. Any idea?From your link:http://www.omc-stepperonline.com/high-torque-nema-42-cnc-stepper-motor-30nm4248ozin-p-74.htmlThis says 8 amps at 5.36 v which sounds weak.Do you think four of these would be equal one golf cart motor. Do you know any links I could start reading about these sort of things.thanksthanks

author: ataradov
author_rank: Super Contributor
timestamp: December 10, 2016, 08:03:34 pm
content: I'm no expert in high power motors, but if I needed to make some rough calculations, they would look something like this. You need to look at a torque. This specific motor has torque of 30Nm, or ~3 kg-force. Assuming that the radius of a golf car tire is ~20 cm, this motor alone could lift ~15 kg mass vertically. So 4 of those motors will be able to lift 60 kg golf cart on an absolutely steep (90 degrees) hill. And if hill is an actual, hill, then this number goes up.30 Nm is a holding torque, so actual running torque will be lower and depends on the rotation speed, but the same logic will apply.But using stepper motors for this is not the best idea ever. Asynchronous motors (with servo controller, if needed) will work much better.

author: ez24
author_rank: Super Contributor
timestamp: December 10, 2016, 08:43:51 pm
content: Quote from: blueskull on December 10, 2016, 08:09:12 pm