I should have asked this question long ago but...

On the table ways of my mill there are screws next to the gibbs that move
the gibbs in and out. What do they adjust?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Glenn Ashmore" wrote in message
news:hLMge.12207$sy6.9902@lakeread04...
I should have asked this question long ago but...

On the table ways of my mill there are screws next to the gibbs that move
the gibbs in and out. What do they adjust?

They tighten the gibbs to take up lost motion in the system.

LLoyd

I'm not talking about the gibb screws on the side. They tighten everything
up. These are in line with the gibb itself and one side of the head fits
into a notch in the gibb. When you turn it, the gibb moves in or out of the
ways from the end.

I am hoping the gibb might be tapered so it can adjust the table level
because I am out about .001 front ot back.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Lloyd E. Sponenburgh" wrote in message
. ..

"Glenn Ashmore" wrote in message
news:hLMge.12207$sy6.9902@lakeread04...
I should have asked this question long ago but...

On the table ways of my mill there are screws next to the gibbs that move
the gibbs in and out. What do they adjust?

They tighten the gibbs to take up lost motion in the system.

LLoyd

FWIW Some mill tables are a little higher in front to compensate for the
sagging effect of heavy work.

Bob Swinney
"Glenn Ashmore" wrote in message
news:hLMge.12207$sy6.9902@lakeread04...
I should have asked this question long ago but...

On the table ways of my mill there are screws next to the gibbs that move
the gibbs in and out. What do they adjust?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Hi Glen,

Depends on the brand of Mill/Drill you have. Most of the larger
versions that I have worked with (those with columns that are bigger
than 4 1/2" in diameter) have a tapered gib. The screw is in a slot so
that you can drive the wedge in or pull it out. The slot in the gib is
larger than the screw head, typically. I just helped a buddy change
this on his so he has opposing screws at each end of the gibs. Like on
most quality lathes. Otherwise, you'll see the gib move back and forth
when you move the slide. Not a lot, but enough that you can feel a
difference in drag (on my buddy's machine).

What do you mean by you are are out by .001 front to back? Is this a
tram measurement? Or do you see this measurement when you move the
table?

Hope this helps in some way,

Doug

It is a gear head square column Rong Fu 45 knockoff with a tilting head. I
have it trammed dead on side to side but can't figure out how to adjust
front to back without shimming the column or the head which would be a real
PITA.

Normally it is not much of a problem but I need to flycut the face of some
6" aluminum plate and it makes the edge of each pass a tiny bit off.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"d.dixson" wrote in message
oups.com...
Hi Glen,

Depends on the brand of Mill/Drill you have. Most of the larger
versions that I have worked with (those with columns that are bigger
than 4 1/2" in diameter) have a tapered gib. The screw is in a slot so
that you can drive the wedge in or pull it out. The slot in the gib is
larger than the screw head, typically. I just helped a buddy change
this on his so he has opposing screws at each end of the gibs. Like on
most quality lathes. Otherwise, you'll see the gib move back and forth
when you move the slide. Not a lot, but enough that you can feel a
difference in drag (on my buddy's machine).

What do you mean by you are are out by .001 front to back? Is this a
tram measurement? Or do you see this measurement when you move the
table?

Hope this helps in some way,

Doug

"Glenn Ashmore" wrote in message
news:XqOge.12210$sy6.7880@lakeread04...
It is a gear head square column Rong Fu 45 knockoff with a tilting head.
I
have it trammed dead on side to side but can't figure out how to adjust
front to back without shimming the column or the head which would be a
real
PITA.

Normally it is not much of a problem but I need to flycut the face of some
6" aluminum plate and it makes the edge of each pass a tiny bit off.

The gib in question will not make that adjustment. Sorry to say, shimming
the column is the way you'll fix the thou error of which you speak unless
the head is adjustable front to back. Bridgeport and clones have that
ability. I don't think any of the mill drill type machines do have.

Before you jump to conclusions, try taking a cut with a large fly cutter,
then offset and cut again. If the cut blends, the error is in the table
surface as it relates to the ways and column.. If it leaves a step, it is
then the saddle sagging (or the column leaning) not the table surface.
It's is possible for either one to be your problem.

When you tighten the gib on the saddle (that's the part that feeds front to
back) it will eliminate side motion, but should have no affect on tilt. The
weight of the saddle and table assembly should be carried by the flat
portion of the ways, with the angular portion used as a guide to keep it
moving in a straight line, front to back, at a right angle to the table.
When you tighten the gib, you decrease clearance between the sliding
surfaces. The only exception to what I said would be if you had a load on
the table such that the weight caused the saddle to try to tip away from the
ways, which is highly unlikely. In such a case, the saddle and table
assembly would be limited in its ability to tilt by the amount of clearance
the saddle has with the ways, which is what the gib is for, to make the
necessary adjustment to minimize the clearance, yet permit smooth movement.

Harold

This is how the gib is adjusted to take out the lateral play. The gib is
tapered in width, and the table is usually ground square and the base is
usually ground with the same taper as the gib (bit not always). As you screw
the gib in it takes up the wear of the whole system. And yes if your table
gets worn in the center it all becomse a compromise. FWIW It's that same on
a my Bridgeport as it is on my mill/drill, just a WHOLE lot bigger :-) If
you plan on takingt he table of for any reason theres a good trick of
measuring how much gib is stick out before you take it apart, makes it easy
to put back together. Screws that push the gib into the table are used to
lock it and usually (but again not always) have handles on them. and yes
this is different than how the gibs are adjusted on my lathe. There the
screws that push on the gib are used to adjust the play.

Also FWIW on my mill/drill the heads of the screws were made by a drunk
(opium smoker?) on a bad day, the were WAY under sized and had a slight
taper to them!. I purchased my mill/drill used (many years ago) and the bozo
who owned had screwd up the slot in the gis where the heads go, It was
really a mess. Fortunatly there was emough meat on the gib left that I could
clean up the slot and then make new screws that fit everything perfictly,
and yes it interesting to use your mill to make repairs on your mill,
meaning you set things up to work on Y, clamp X tight a a drum pull the gib
out and machine it, then do the same thing for Y, clamp it tight and then
pull the pieces and work on X.

Dave


"Glenn Ashmore" wrote in message
news:hLMge.12207$sy6.9902@lakeread04...
I should have asked this question long ago but...

On the table ways of my mill there are screws next to the gibbs that move
the gibbs in and out. What do they adjust?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Glenn Ashmore wrote:

I'm not talking about the gibb screws on the side. They tighten everything
up. These are in line with the gibb itself and one side of the head fits
into a notch in the gibb. When you turn it, the gibb moves in or out of the
ways from the end.

I am hoping the gibb might be tapered so it can adjust the table level
because I am out about .001 front ot back.

This sets and holds the Gib that is tapered at a defined depth and thus side pressure.

These are on my lathe and mill. Standard for dovetails that carry load. Wear, just re-adjust.

Martin

--
Martin Eastburn
@ home at Lion's Lair with our computer lionslair at consolidated dot net
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder

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