Spindle Tab nut tightness?

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andy_con
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Spindle Tab nut tightness?

Post by andy_con » Mon 23 Nov , 2015 21:36 pm

when doing up the tab nut on the spindle how tight does it need to be? tight enough till it stops spinning freely? or tighter so there is no play (up and down play) in the spindle?

angel-tech
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Re: Spindle Tab nut tightness?

Post by angel-tech » Tue 24 Nov , 2015 4:12 am

you have to set the right amount of preload onto the bearings so a fair bit of tightening is required

andy_con
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Re: Spindle Tab nut tightness?

Post by andy_con » Tue 24 Nov , 2015 10:57 am

Ok thanks.

So ignore the free spinning of the spindle.

Currently I've not done it mega tight and it does spin very freely, but it has a fair amount of up and down movement/wobble.

I'll keep tightening tonight

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Re: Spindle Tab nut tightness?

Post by angel-tech » Tue 24 Nov , 2015 13:12 pm

I don't know the correct torque to clamp it up to, you just get a good feel for it after a while. Needless to say there can't be any play in the spindle, and vice versa it can't be too tight. The most important thing is to get everything clean before you fit the bearings, and make sure they're fitted correctly.

andy_con
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Re: Spindle Tab nut tightness?

Post by andy_con » Tue 24 Nov , 2015 13:27 pm

angel-tech wrote:I don't know the correct torque to clamp it up to, you just get a good feel for it after a while. Needless to say there can't be any play in the spindle, and vice versa it can't be too tight. The most important thing is to get everything clean before you fit the bearings, and make sure they're fitted correctly.
yep i made sure everything was spotless and they are fitted the correct way round.

its just trying to get the tab nut sorted, like i say ive only done it up a little and the spindle moved up and down by hand. so ill tighten a bit more tonight and see how it goes.

thanks for the info

andy_con
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Re: Spindle Tab nut tightness?

Post by andy_con » Tue 24 Nov , 2015 21:16 pm

after some faffing I think ive got it right.

id tighten the tab nut so there was no play then gently tap the spindle with a hammer and play would appear. so I kept tightening until I tapped the spindle with a hammer and no play appeared. now the spindle feels smooth and silent

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Re: Spindle Tab nut tightness?

Post by angel-tech » Wed 25 Nov , 2015 0:29 am

maybe tighten up to the next tab, to put a small preload on the bearings.

PS i'm in now if you still want to ring.

andy_con
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Re: Spindle Tab nut tightness?

Post by andy_con » Wed 25 Nov , 2015 13:16 pm

i did do that last night, the machine is pretty much back together now and ive ran the spindle and its sounds pretty good.

when i got the bearings i made sure they came with specs so i knew exactly what i was buying, i wanted to future proof them for a possible spindle upgrade. the bearings are rated at 19k rpm with grease lubrication or 26k rpm with oil lubrication. the bearing place were saying being open bearings as soon as they get warm/hot lubrication starts to run out.

well the bearings in a triac arent lubricated full stop.

anyone got any thoughts on this?

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