Ballnut mount screw size

[ViperTX]

Okay, just machined the mount (1.566 in. wide, 1.231 in. high and 1.066 inch thick). With the 0.875 in. dia. hole for the 15/16-16 tap, I end up with about 0.290 in. on both sides of the tapped hole.

So, that basically eliminates the use of 1/4-20 for mounting the mount to the underside of the y-axis table, 10-32 requires about 0.190 max., so that moves me into the 8-32 with a 0.164 max.

What do you think of using 8-32 SHCS that are going to be about 1 1/4 to 1 1/2 inch long and go into the mount about 0.6 inches? That would be how the ballnut mount is attached to the y-axis plate.

[Ken_Shea]

Personally I believe they will work fine, a rotating load on the mount is nill, the pushing force I would not think would not reach any where the limits of even the 8-32.

Can you add a few extra to each mount just to make you feel better about it ?

[Mcgyver]

yuck, I'd be waiting for the ViperTX guy to give me the right answer! small cap heads but more of them give the same clamping force without overtorquing? that or make a new one...sorry I don't anything more imaginative

oops Ken ya beat me to it

[ViperTX]

I should be able to use 4 size 8 screws. The mount is made of Fortal (AL 7075).

Well the size is dictated by the space constraints....I have about 0.125 clearance on each side of the mount so it can whiz by the bearing trucks..... .... What a screw up....it doesn't have to whiz by the bearing trucks....geesch, it just has to clear the surface where the rails are mounted.

Thanks.

[Ken_Shea]

4 should do it, the block is small, sometimes you just have to do what you have to do, if it doesn't work then I never suggested anything and you cant prove I did