ballscrewed. literally.

[vacpress]

So, I ordered 2 used screws off ebay for $200.

They came very poorly packaged. Packaged as only a truley careless and cheap person would package such items. Taped together, wrapped in 1 wrapping of bubble wrap, in a box covered in duct tape..

Needless to say there was damage from shipping.

Somehow the smaller screw (THK WF2040) turned out fine, but the larger screw (THK WF2550) has been bent.

Before you tell me that my screw is useless, it is only bent after the bearing block. What seems to have happened is that the package was dropped on the ~5" belt pulley the person didnt remove from the shaft. Had they removed the large pulleys, there never would have been enough leverage to bend the .5"(dia) of steel left on the 25mm ballscrew shaft end..(the screw is about 50inches long)

My question is: How do i find out about getting this repaired? It is about 3deg out of alignment. Pictures will follow as soon as i find a digital camera to borrow.

I can probably spend upto $100 to get this repaired, any more would be upsetting. This whole incident is upsetting. I cannot imagine the mindset of a person who sends out extremely nice (they were\are) precision components packaged appropriately for an aluminum baseball bat.

please help!!! I will post pictures with details this evening, hopefully.

Robert

[vacpress]

note: ive got a 'bench press', some hammers, etc.. i am very tempted to just go at the thing trying to get it as straight as possible, but also would like input from anyone who knows about such things...

i am a cross between sad and livid.. really.. who does this sort of thing? people are a constant disapointment.

[posix]

well since you said the kink is after the bearing block then all is fine!
first I'd go find me a competent machinist of the lathe type. he'll be able to straighten it somewhat by turning it slowly and applying pressure to the bit sticking out in the opposite direction. it can be brought down to around +-1 deg. then simply turn it down to a smaller OD or even a conical shape and you're sorted! as long as your "threads" are fine and the bearing block can fit. good luck!

p.s. oh and this will be no more than 10 minutes on the lathe so I guess $10 should cover it (including tips)?

[Al_The_Man]

First off I would go back to the seller and ask what if anything he intends to do in the circumstance, 99% of the time I recieve ebay items that are very well packaged, but a recent one took the cake, I purchased a 75lb motor that was in a cardboard box, with absolutely nothing for packing. Needless to say the armature had been smashed through the endbell.
The first response I got from the seller was to claim from UPS, they would have just laughed.
I insisted and he refunded the whole amount, fortunately.
If he does'nt respond, leave a negative for him.
Al.

[vacpress]

al, sure. ive still got my feedback in reserve to see what he says... i am still shaking my head over this.. he taped the 2 screws directly to one another with packing tape!

Posix,

Yes, this is what i was hoping.. One possible problem is that the screw is 1" diameter, and 50-some-odd inches long.. just taking the bearings off would take more than 10 minutes... But, the screw itself besides being bent is OK. Somehow the shipping didnt even really effect the black oxide-type coating, or whatever it is that makes them black.


Posix,

How might I go about finding such a machinist? There is one that advertises here and is located in geneva, a rather far drive from chicago...

Thanks for the quick replys... I knew the answer was going to be something like this...


GRRRR..

[posix]

best bet is to go find a local independent auto mechanic (you know one of those specialists that only do one particular make or even model like alfa romeos or classic bmws or whatever) and ask them where they skim their discs or what machinist they use for work on shafts or whatnot. I'm sure they'll be glad to give you a few phone numbers.

[vacpress]

posix-thanks!

grrr. what a stinking waste of time\pain in arse.

if any of you are ever selling 5' long ballscrwews on ebay, please wrap them appropriately!