# replace plastic gibs in 12" atlas?



## bkcorwin (Oct 20, 2013)

Hi all, I need some new gibs.  I was shocked when I took apart my late model 12" and found plastic gibs.  The internet later revealed this is how they were equipped in the late 70s.  

That said, the ones I have are cracked and dented in quite far.  What have people used to fashion new gibs?  I saw one person used brass and am thinking I may go that route as well. Thoughts?


Thanks much
Brian


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## GoMopar440 (Oct 20, 2013)

Rather than brass, what about using Oilite Bronze? The self lubricating properties should work rather well in that application I would think. Either that or possibly make some solid teflon gibs if you have any concerns about the hardness of the metal areas around the gib channel.


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## wa5cab (Oct 21, 2013)

Brian,

The Internet is unfortunately full of disinformation (like Atlas 618's having 1"-8 spindle nose threads).  The original gibs are steel.  My 3996 was made the Summer of 1980 and it has all steel gibs.  The part numbers are the same from when the 1/2" bed machines were first introduced in late 1957 up through the last machine produced in 1981.  The only Atlas machine I know of that might have had plastic gibs is the MK2, which I'll refrain from commenting on.

For restoration, I would first call Clausing and see whether or not they still have some available.  If not, ask them to send you a PDF of the original drawing (they won't do this if they still have them for sale).  Then order some precision ground steel flat bar from some place like McMaster.  You might have to buy 3 feet of it.  But that will give you extra in case your first attempt is less than successful.

FWIW, straight Teflon is not a good material for applications like gibs.  It is subject to cold flow at very low pressures, which will certainly occur within a few months in an application like a screw-adjusted gib.  So, for that matter, are most "modern" plastics.  

Robert D.


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## GoMopar440 (Oct 21, 2013)

wa5cab said:


> FWIW, straight Teflon is not a good material for applications like gibs.  It is subject to cold flow at very low pressures, which will certainly occur within a few months in an application like a screw-adjusted gib.  So, for that matter, are most "modern" plastics.
> 
> Robert D.



Good to know. I wasn't aware about the cold flow issue. I have a piece of teflon that's big enough to make a couple gibs out of it, so I had thought about making some is why I mentioned it.


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## bkcorwin (Oct 21, 2013)

How interesting.  I wonder if there is any difference in that it is a craftsman lathe made by atlas.  

It really suprises me that the original owner would have at some point replaced the gibs with these plastic ones.  The machine itself has basically no wear so I can't understand why the gibs would've been swapped.

THe internet also told me that if you contact clausing now to buy new gibs they supply plastic ones.

Curious

B


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## Uncle Buck (Oct 21, 2013)

bkcorwin said:


> How interesting.  I wonder if there is any difference in that it is a craftsman lathe made by atlas.
> 
> It really suprises me that the original owner would have at some point replaced the gibs with these plastic ones.  The machine itself has basically no wear so I can't understand why the gibs would've been swapped.
> 
> ...



The only way to know what they will tell you for sure is to call them. I bet you the gibs will not be plastic though.


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## bkcorwin (Oct 21, 2013)

http://groups.yahoo.com/neo/groups/atlas_craftsman/conversations/topics/42156

http://groups.yahoo.com/neo/groups/atlas_craftsman/conversations/topics/71916

A few references to what I'm talking about

I'll call them this afternoon.  Does anyone have a model number for a 12x36 lathe.  They want a model number and my lathe is in my garage and I am at the office.

​


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## wa5cab (Oct 22, 2013)

Brian,

Unfortunately (since you asked your model number question right after lunch), it is usually late at night before I check on H-M.  I'm sure that by now you've looked at your machine, but if not, the later 12x36 cabinet machine is the 3996.  The earlier one (1958-1966) is 3991.  The equivalent bench machines are 3986 and 3980.

The later of the two message threads you found is about the Atlas 3950, the first version of the 6" MK2.  I'm not surprised that it might have come with plastic gibs.  It was only in production for less than a year.  The other thread was about a 10" back in 2006.  My opinion is about the same as expressed in that thread.  Hopefully, Clausing have come to their senses.  But if not, they probably won't send you the drawing.  I'm quite disappointed to hear that they've supplied unsatisfactory substitute parts.

Robert D.


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## Uncle Buck (Oct 22, 2013)

WOW, so plastic gibs was true. So very disappointing. The reputation for gears and the rest is bad enough without adding plastic to the mix! 



wa5cab said:


> Brian,
> 
> Unfortunately (since you asked your model number question right after lunch), it is usually late at night before I check on H-M.  I'm sure that by now you've looked at your machine, but if not, the later 12x36 cabinet machine is the 3996.  The earlier one (1958-1966) is 3991.  The equivalent bench machines are 3986 and 3980.
> 
> ...


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## wa5cab (Oct 22, 2013)

Uncle Buck,

According to your message trailer, you have a 6" MK2, presumably a 10100.  What gib material does it have?

Robert D


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## Uncle Buck (Oct 22, 2013)

wa5cab said:


> Uncle Buck,
> 
> According to your message trailer, you have a 6" MK2, presumably a 10100.  What gib material does it have?
> 
> Robert D



I must admit, it is a project waiting for parts that I cannot seem to find. I need a new backgear and step pulley for starters. That is the one with the combined stud gear. I also think I might be missing a gear or two and the plastic gear cover. I am actually a bit AR in some respects. I will not even bother tearing the machine down for a rebuild until I find these parts so I cannot say what the gibs on the machine are made of.


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