# Micro-mark 7x16 lathe bearing upgrade



## Sk8ter (May 3, 2013)

The project of the day today.... was to Remove the ball bearings in the headstock and replace with a taper roller bearings....


I am sorry i did not take pictures but i just wanted to get it done...


if you own a seig 7x lathe this should be at the very top of the list to do IMO

the improvement is quite huge makes you feel like you have a precision lathe )) 
NO MORE Chatter!!!

a worthy 34 dollar upgrade 

Lawrence


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## LEEQ (May 3, 2013)

All the 7x? lathes are the same, right? As in what bearing numbers did you use in yours so I can put them in my grizzly?


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## Sk8ter (May 3, 2013)

I am assuming yes it should be the same even the 2 speed gearbox version should be the same here is what i bought...



http://www.ebay.com/itm/360392190971?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649


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## LEEQ (May 3, 2013)

Two of these?














         30206 is single-row tapered roller bearing can support a combined radial and axial load, the cage is Chrome Steel, 30206 inner diameter is 30mm, 30206 outer diameter is 62mm and 30206 width is 16mm.        


Item: 30206 Nachi Ball Bearing
[*]Type: Nachi Tapered Roller Ball Bearing
[*]Cage: Chrome Steel
[*]Dimensions: 30mm x 62mm x 16mm/Metric
[*]ID (inner diameter)/Bore: 30mm
[*]OD (outer diameter): 62mm
[*]Width/Height/thickness: 16mm
[*]Size: 30 x 62 x 16 mm
[*]Quantity: One Bearing
[*]Dynamic load rating Cr: 41,500 N
[*]Static load rating Cor: 44,800 N
[*]Limiting Speed:

Grease Lubrication: 6,500 RPM
Oil Lubrication: 8,700 RPM

[*]Made in Japan



*Dimensions (mm)*
 d
D
B
T
c
r
a
30
62
16
17.25
14
1~1.6 
3.1


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## Sk8ter (May 3, 2013)

Yes but not so sure you should have posted that...but yes this is what i used..


you will most likely need to trim down one or both of the plastic spacers on the gear side of the spindle...if you need more help just ask



Lawrence


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## LEEQ (May 3, 2013)

Think I can wing it, my ex was right abt one thing, I don't own anything I haven't modified.     I wanted to preserve the bearing info for after that listing is gone. I think it will be ok.


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## Sk8ter (May 3, 2013)

alright great then...maybe you can post some pictures where i didn't 


not too bad my suggestions would be after removing the OB clean the seating area good...


the rest should be straight forward....

any help i do be just ask..


Lawrence


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## Dunc1 (May 4, 2013)

Arc Eurotrade (usual disclaimers) offer a pictorial guide to changing the bearings
http://www.arceurotrade.co.uk/machineguides/C3 Mini-Lathe Dismantling and Reassembly Guide.pdf


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## wrmiller (May 5, 2013)

Wow, this is great info. Just bought a 7x16 and am fixing/upgrading some stuff. Would be a great time to do this?  

Edit: Is this possible without a press? Just realized the spindle/bearings are probably press fit.


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## Sk8ter (May 6, 2013)

Trigrman said:


> I'm in the middle of upgrading the bearings on the POS Micro Mark 7x16 myself. I'm beginning to think I made a huge mistake buying it and selling my eleven year old HF that I tweaked to the max. So far EVERYTHING that should be accurate isn't even close! Now I find that the Head Stock doesn't even sit flat! It rocks up and down on the flat side(back) and won't even contact the prism correctly on the front. I'm so ****** I'm contemplating boxing the whole thing up and shipping it back to those shysters in NJ!  :*****slap2:
> 
> Rant Over (sorry bout that folks):whiteflag:
> 
> ...




sorry your having a hard time...what is an HF lathe? 

sounds like you have gotten a lemon...the micro-mark seig 7X versions are suppose to be better (more accurate) right out of the box.....mine did require some special attention but overall its good to go and mucho better now with the taper bearing....

I did not require a press to remove the bearings when i got the spindle out the bearings stayed in there ...so i used some wood and hammer and got them out...cleaned the bearing area real good and tapped in the new bearing race....once started square in the boar just tap them you can use the old bearing to do the final seating of the race....


this setup does not have adjustability  for the front and rear separately but singly all done with the spanner collar nut i hope this makes sense...

but if your lathes headstock is not square to the bed you will never make it right....contact them immediately!!! do not wait let them take care of the shipping etc...let them make it right...from what i have seen so far micro-mark is an ok company .....remember no one is a mind reader you must explain and tell your story them...

I will say nothing is perfect either but when you get the little stuff sorted out and put taper bearings in you understand how good things can be..


Lawrence

- - - Updated - - -



wrmiller19 said:


> Wow, this is great info. Just bought a 7x16 and am fixing/upgrading some stuff. Would be a great time to do this?
> 
> Edit: Is this possible without a press? Just realized the spindle/bearings are probably press fit.



yes and no.....until you live with the crappy ball bearings you would never appreciate how much better the taper bearings really are...

I will say getter done will save you a ton of grief in the long run 


I can/will help if you need it just ask


Lawrence


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## itsme_Bernie (May 6, 2013)

Dunc1 said:


> Arc Eurotrade (usual disclaimers) offer a pictorial guide to changing the bearings
> http://www.arceurotrade.co.uk/machineguides/C3 Mini-Lathe Dismantling and Reassembly Guide.pdf



Wow I don't even have one of these and I read the whole rebuild site that Dunc1 posted!   Hah hah

Hey Lawrence- did you upgrade any of the other parts of your machine, like the saddle, or compound?   I would be curious to see how one of your machines would feel after upgrading like this.  

I think this is also a good illustration of why precision machines cost what they do.  I know the original parts can be made a little better in the first place, but all the "hand fitting" takes time and care.

What a great page!  I have to look for a similar Atlas 618/Craftsman page!


Bernie


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## Sk8ter (May 6, 2013)

itsme_Bernie said:


> Wow I don't even have one of these and I read the whole rebuild site that Dunc1 posted!   Hah hah
> 
> Hey Lawrence- did you upgrade any of the other parts of your machine, like the saddle, or compound?   I would be curious to see how one of your machines would feel after upgrading like this.
> 
> ...




I made use of a longer cross screw and milled out the cross base  for more travel...lots more travel...actually more travel then you can turn diam wise......

tailstock has been modified I removed the cam lock... what a joke.......camlock mech work in much bigger lathes they don't work good(enough clamping force) for these...I also added a much larger hand wheel and made a better T-nut..... now when  you clamp the damn tailstock down it stays right where you clamp it!!

I will say this ...when you do the taper roller bearing upgrade and go through and red locktite all the set screws and  gibs etc...everything will stay good and tight no more chatter issues 
and you wont have to re-adjust everything for a awhile....

hope this helps

Lawrence


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## parastoo (Oct 17, 2013)

Hi,
   How did you reduce the thickness of the spacers? Can you do it without access to a second lathe?
   Thanks, 
             Mark


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## Sk8ter (Oct 21, 2013)

parastoo said:


> Hi,
> How did you reduce the thickness of the spacers? Can you do it without access to a second lathe?
> Thanks,
> Mark



Hello ...I have been in hiding for awhile cleaning up the shop and finishing my machining projects...

Right so..yes you can reduce these plastic spacers  without a lathe its not a critical part per say just takes up some space....If i can remember correctly take off .100 or there about...should do the trick..

Please remember this is not a fix all for these little machines everything works in tandem so if its not adjusted correctly gibs etc.. you may not see how much better this machine can be....

ok so been using the lathe this way for several months..... its a huge improvement its so huge that micromark should offer this as an inexpensive upgrade , hell I would have paid an extra 50 bucks for this....

the other thing i wanted to mention about my personal micromark is the chuck is the best chuck I have ever seen...... its repeatability is .0015 every time! I am surprised no one else has reported this ...


remember....... have some fun relax....... it will and can take a few years before you get the hang of our fun hobby 

Lawrence


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