Need clamping screw

[bob91343]

I picked up a stand fan SKY3865 that is missing some parts.  The display is gone, which is no big deal, but there is a screw missing and it's a thread I don't know.  It's the knob and screw that clamps the motor assembly to the vertical post.  So now the motor wobbles on the stand and I'd like to find a bit of hardware to put in there.

It's bigger than 1/4-20 and I think it's metric.  I left a msg online but the factory insists I prove I am the original buyer (which I am not).

Anyone know about this?

[JacobPilsen]

M8x1.25 is the most common metric screw "bigger than 1/4-20".
M6x1 is smaller.
And M7x1 is pretty uncommon.

If you can't buy it from your local store, buy it online.
Sometimes it's much easier.

What about lenght ?

[jpanhalt]

Does the screw go into a proper nut or pressed sheet metal.  In the latter instance, I have seen Whitworth threads (55° included angle) used on a Chinese import.  Whitworth screws are hard to find.  Their dimensions are in inches.

[bob91343]

The screw goes into a plastic affair.  There are only three or so threads so I can see why the screw has been lost.

I may try to fit a 1/4-20 with nut, depending on how much clearance there is.  I just figured I'd ask in case someone had something that would work.  I could even glue the parts together, and break apart the glue should I need to disassemble it.

The whole fan is a piece of junk.  I don't recommend it.  I picked it up free on Craigslist and it's barely worth the gasoline to do that.  I think it goes for around $50 - save your money.

Update edit:  Problem solved!  I fitted a 1/4-20 bolt with nut that perfectly holds in the slot.  It's needs a screwdriver to loosen but I can't imagine needing to do that unless I am moving, which I am not.

[andy3055]

Replace the nut with a butterfly nut for easy adjusting.

[bob91343]

I thought I might somehow mount a large knob to the bolt and then it would be almost as it was designed.  But my solution does everything I need and I am fine with it.  Further, with a bolt I can can tighten it more for better security.

As I said, a lousy design.  The heavy motor and, actually, all the moving and controlling parts, are supported by this one bolt.  In time, without a locking device, it will loosen and cause wobble and thus shorten the life.  And make noise.

On the other hand, it's kind of cool looking.  It has some useless functions as well, but they were struggling to add value.  My guess is that the unit won't last long, maybe motor or bearing failure, who knows.  For now, it works.