# Is there supposed be some sort of gib on carriage?



## Shotgun (Jun 23, 2022)

I've got tapered gibs on my cross-slide and compound.  But, I can't find any "tightening" mechanism for the carriage.  Is it just supposed to float on the v-ways, with nothing to stop vertical movement except a loosely-fitted hold-down bar on the front and back?

My last, and only other lathe, was an Atlas 12x36, with flat ways.  It had the multiple set screw type gib.


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## benmychree (Jun 23, 2022)

That is pretty much normal with lathes with vee ways, the weight of the apron pretty much holds the front down on the vee way, and if you have a taper attachment, it does the job on the back.  It is good to have loosely fitting flat gibs to limit upward motion of the carriage to avoid damage if something untoward might happen that would cause the carriage to lift.


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## theresamartinez (Jul 12, 2022)

There is a new type of lathes that have come out on the market that are CNC lathes, I don't know if you had previously taken a look at them


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## Firebrick43 (Jul 12, 2022)

Shotgun said:


> I've got tapered gibs on my cross-slide and compound.  But, I can't find any "tightening" mechanism for the carriage.  Is it just supposed to float on the v-ways, with nothing to stop vertical movement except a loosely-fitted hold-down bar on the front and back?
> 
> My last, and only other lathe, was an Atlas 12x36, with flat ways.  It had the multiple set screw type gib.


If you have tapered gibs on the cross slide or compound, they are there on the carriage.  V way lathes may forgo fore and aft gibs but they still have one in the front and back on the bottom to hold down the carriage, otherwise the back would pivot up on heavy cuts.  Its there, some lathes are pretty hard to see without a flashlight.  

I say that, I guess it MAY have peelable shims under the hold down flanges, just like an atlas lathe does.  







What model of lathe is it?


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## Shotgun (Jul 12, 2022)

Firebrick43 said:


> If you have tapered gibs on the cross slide or compound, they are there on the carriage.  V way lathes may forgo fore and aft gibs but they still have one in the front and back on the bottom to hold down the carriage, otherwise the back would pivot up on heavy cuts.  Its there, some lathes are pretty hard to see without a flashlight.
> 
> I say that, I guess it MAY have peelable shims under the hold down flanges, just like an atlas lathe does.
> 
> ...


It's a Sebastian H-model.  It has V-ways on both sides (front and back).  I had the hold down flange off of the back, but there was no shim.  I guess I should make a set?


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## benmychree (Jul 12, 2022)

If there is any wear on the upper ways, trying to keep a close clearance on the lower surfaces is going to cause binding when you travel to the less worn surfaces towards the tailstock; the reason for the gib strips below the upper ways is to limit lifting if the carriage during untoward events like heavy cuts and other accidental events.


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## Richard King 2 (Jul 12, 2022)

This is a Southbend copy, but on Page 66 it shows the tapered gib adjustment.  Also on some lathes they use a rectangular gib that uses set screws with Jam nuts the push in from the back side of the gib.  Take a few pictures of the cross-slide so we can see. 


			https://cdn0.grizzly.com/manuals/sb1013f_m.pdf


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## Richard King 2 (Jul 12, 2022)

I see this in UK lathes and it looks like the cross-slide has a tapered gib.  Looks like there are 2 gib screws.  Take  some pictures so we se exactly what you have frond, side and back.  I see you have pictures of your headstock post.  Lets see the rest of the machine.  http://www.lathes.co.uk/sebastian/page4.html


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## Shotgun (Jul 12, 2022)

As much as I'd searched, I hadn't found that page on UK lathes.  Thank you.
But, I'm not talking about the cross-slide or compound.  Both of those have tapered gibs (and are very tight and smooth).
It is the carriage that sets on two V-ways, but nothing to hold it down tight. Yeah, that's right.  The carriage sits on two V-ways.  No one V-way and then a flat on the other side.  The tailstock also sits on two V-ways.  As @benmychree, is pointing out, I think the bar that bolts on to the bottom of the carriage on the back side is just to keep the carriage from popping up in a crash.


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## stupoty (Jul 12, 2022)

theresamartinez said:


> There is a new type of lathes that have come out on the market that are CNC lathes, I don't know if you had previously taken a look at them



And todays most random post prizes goes tooooo......


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## Richard King 2 (Jul 12, 2022)

Many or I would say most lathes only have a lock on the front right side with a locking and unlocking screw and a hold down strip on the back bottom of the saddle which is a flat bar.  I have seen those back clamps with flat cast iron pads that are adjustable on Bigger swing lathes..  Sorry I read the first post ass backwards.  The more expensive lathes have hold down L shaped hold downs on the bottom front of the saddle.  I have never seen a lathe with a tapered gib under there (front under saddle) on any lathe.   If there are some threaded holes under the saddle and no clamps,, someone left them out.  If no holes then it never had any and I wouldn't  worry about it.


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