Re: [CAD_CAM_EDM_DRO] re:Final leadscrew design - thanks to all (not yet?!?!)

Ron & Ballendo:

>I'm going to repeat the "talk-through" of my earlier post. Pretend
>you are making this "fixed style" mount as you read. To avoid
>confusion, I will leave out the description of any mounting holes for
>the finished assembly. I am also going to "assume" that a 1.25
>bearing will fit in a 1.25 bore.(In other words, std.clearances will
>be ASSUMED)

(snip)

>If the bearings are "face ground angular contact matched pair",
>you're done!
>
>If you are using the plain radial bearings to save money, you have
>another step. measure the "end play" in the shaft(while the mount is
>assembled) disassemble, and put this "discovered" thickness of "shim"
>washers between the bearings. If you have worked carefully, you now
>have a fixed mount with a thrust capacity equal to ONE bearings
>RADIAL capacity.(see previous posts)

I just up-loaded a drawing "leadscrew.jpg" that I think depicts this
mounting. Ballendo, please let me know if this is not what you had
in mind. If it is OK I hope it clears up some of the confusion.

So, if the bearings are "face ground angular contact pair" they are
made to be correctly pre-loaded when forced face to face? i.e. no
slop. How about the "double row ball bearings" or "double row angular
contact bearings". Are these built with a pre-load so there is no slop
or simply to take more load than a single row? I looked at the SKF site
a little but couldn't determine if this were the case. (Well, I didn't spend
a lot of time looking. :-) ).

Thanks.

Hugh
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Hugh & Denise Currin
currin@...
Klamath Falls, Oregon USA
541/884-3023
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