ACME screw bearing size

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H in OH
Posts: 6
Joined: Tue Oct 28, 2014 3:47 am

ACME screw bearing size

Post by H in OH » Tue Oct 28, 2014 4:37 am

What is the outer diameter for the flange bearings (not counting the flanges) intended for the SO2 3/8" Acme screw mounting kits? I ask while thinking about using a larger diameter screw to lift a heavier load in the Z axis.

Thanks,
---H

crazeegeek
Posts: 118
Joined: Thu Mar 13, 2014 9:37 pm

Re: ACME screw bearing size

Post by crazeegeek » Tue Oct 28, 2014 10:06 am

It uses the same flanged bearing(F608-ZZ) as the stock SO2, which has a 22mm OD.

H in OH
Posts: 6
Joined: Tue Oct 28, 2014 3:47 am

Re: ACME screw bearing size

Post by H in OH » Sun Nov 02, 2014 4:10 am

crazeegeek wrote:It uses the same flanged bearing(F608-ZZ) as the stock SO2, which has a 22mm OD.
So the ACME screw must have its leads ground to an 8mm diameter. How far is the lead ground down on both sides?

Thanks,
---H

Improbable Construct
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Re: ACME screw bearing size

Post by Improbable Construct » Sun Nov 02, 2014 1:18 pm

The screw is turned down to 7.92 mm diameter to fit into the bearing. One end has 7 mm turned down along its length the other end has 30 mm turned down.
Shapeoko #Classified some of the bolts may be original parts.
Shapeoko 1 # ???? Stainless plates, still in the box.
Shapeoko 2 # 3926 not stock
Shapeoko 3 # 0003
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H in OH
Posts: 6
Joined: Tue Oct 28, 2014 3:47 am

Re: ACME screw bearing size

Post by H in OH » Sun Nov 09, 2014 12:11 am

It looks like there is a fair amount of front-to-back adjustment in the bearing mounting plate design. Is there enough for clearance of a 1/2 inch screw and nut instead of a 3/8 screw? The best way to tell is probably what is the maximum clearance from the edge of the rail to the center of the screw/bearing if the bearing plate is as far out as the mounting screws will allow?

Thanks.
---H

Improbable Construct
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Re: ACME screw bearing size

Post by Improbable Construct » Sun Nov 09, 2014 1:05 am

There is 9mm from the edge of the makerslide to the center of the hole in the plate when it is fully extended. A 1/2" acme screw is ~12.7mm. Half of that is ~6.35mm. That would give you 2.65mm of room for the wall of the nut. So, yes it should be possible but the question is why would you need/want to do it. :)
Shapeoko #Classified some of the bolts may be original parts.
Shapeoko 1 # ???? Stainless plates, still in the box.
Shapeoko 2 # 3926 not stock
Shapeoko 3 # 0003
Store:
http://ImprobableConstruct.com
Twitter:
https://twitter.com/ImprblConstruct

H in OH
Posts: 6
Joined: Tue Oct 28, 2014 3:47 am

Re: ACME screw bearing size

Post by H in OH » Sun Nov 09, 2014 6:24 pm

Improbable Construct wrote: So, yes it should be possible but the question is why would you need/want to do it. :)
Keeping options open since I want to lift about 20lbs. up a 34in. long slide track. Not sure if a 3/8 screw can handle the weight or avoid deflecting in that distance.

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