# HELP! NEEDED    G0704 Mill   X-Axis Gib DOES NOT FIT



## angelfj1 (Apr 3, 2014)

OK I know you're out there - all you Grizzly G0704 Mill owners.  I'm more than a bit embarassed but I must be doing something wrong.

I have completely disassembled the mill to clean and adjust everything.  I reassembled the X-Y saddle onto the base, adjusted for backlash, inserted the Y-axis gib, and the saddle glides back and forth very nicely.  No such luck with the table.  When trying to put the  table onto the saddle, I can't completely insert the X-axis gib.  The X-axis gib is approximately 7 inches long which is the "X" dimension of the saddle.  I can insert the first 5.5 inches and then the table, gib and saddle seize up.  This is not by lack of gentle persuasion.  In fact, at one point, I tried to tap the end of the gib with a small brass drift.  Bad idea!  The gib got jammed between the table and saddle and would not budge.  I eventually had to use a piece of brass rod to drive it out from the opposite end.  I hope I'm doing this the correct way.  First I engage the table into the saddle dovetails, center the table on the saddle and then insert the narrow end of the gib from right to left.   

Just to clarify, at this point both X-axis gib adjustment screws are out and the X-axis leadscrew has not yet been installed.

I really can't proceed until I get this problem solved. 

Thanks in advance.

Frank


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## kizmit99 (Apr 3, 2014)

I know this isn't much help, but I'm pretty sure that when I removed and reassembled my table that the x-axis gib slid right out and right back in without any issues.  I know I took great pains to make sure that I was sliding in back in in exactly the same orientation that it came out.  Maybe you managed to flip it end for end or top to bottom?  It sounds like the procedure you're using to put it together is the same way I did it, table centered and sliding the gib in from the right (when facing the front of the machine).  I would try installing it in all four possible orientations to see if any work any better, just to check whether you managed to flip it while it was out...

Good luck getting it back together!


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## angelfj1 (Apr 3, 2014)

kizmit99 said:


> I know this isn't much help, but I'm pretty sure that when I removed and reassembled my table that the x-axis gib slid right out and right back in without any issues.  I know I took great pains to make sure that I was sliding in back in in exactly the same orientation that it came out.  Maybe you managed to flip it end for end or top to bottom?  It sounds like the procedure you're using to put it together is the same way I did it, table centered and sliding the gib in from the right (when facing the front of the machine).  I would try installing it in all four possible orientations to see if any work any better, just to check whether you managed to flip it while it was out...
> 
> Good luck getting it back together!



kizmit99, thanks for your reply and suggestion.  I will try this, but I think I may have already. I know that gibs don't grow!  There must be something that I have done or haven't done that is preventing the gib from sliding in place.

Thanks again,

Frank


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## kizmit99 (Apr 4, 2014)

I thought of one more thing - I don't recall whether or not there were brass pins that lock down screws actually tightened against the gib itself, but I suspect there were (I have a vague memory of them falling out when I removed my table).  If so, it's possible that one of them slipped deeper into the hole, instead of falling out and it's now blocking the gib from being reinserted.  Good luck.


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## BenjamanQ (Apr 4, 2014)

That's a good point kizmet99. I''ve seen that before; the screws contact little pins that in turn contact the gib. This prevents the screws from deforming the gib but could be a problem at reassembly. It might be a good idea to pull the table and verify that nothing is in the screw holes.


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## SEK_22Hornet (Apr 4, 2014)

I'll have to look at mine, but I'm pretty sure that the gib adjustment screw for the table in on the right side (facing the machine), so the gib should go in from the right. Make sure the locks are completely out of the way and that the table is seated on the dovetail properly. Unless there is something in the way, the gib should go in relatively easy. Take it apart and make sure there is nothing out of place like the gib locks - I'd remove them entirely and install them after the gib is back in place.


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## jumps4 (Apr 4, 2014)

hi Frank
I had a problem with the 704 build I did for baconbits here, I must have mixed up where each gib came from. I kept swapping them around until I found the original locations. I think it was x and z but  I'm not sure now. also make sure the drain hole in the table is facing back and not forward. It took me quite a while to figure it out. the hand scraped side goes against the dovetail. do not tighten just snug the adjustment screws until you figure out where they go. the screws can bind the gib and make it seems like it fits when it's wrong. the gib adjustment screws are too small and will cock the head of the screw wedging the gib
each gib was hand fit to it's position and scraped to fit correctly.
steve


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## angelfj1 (Apr 4, 2014)

jumps4 said:


> hi Frank
> I had a problem with the 704 build I did for baconbits here, I must have mixed up where each gib came from. I kept swapping them around until I found the original locations. I think it was x and z but  I'm not sure now. also make sure the drain hole in the table is facing back and not forward. It took me quite a while to figure it out. the hand scraped side goes against the dovetail. do not tighten just snug the adjustment screws until you figure out where they go. the screws can bind the gib and make it seems like it fits when it's wrong. the gib adjustment screws are too small and will cock the head of the screw wedging the gib
> each gib was hand fit to it's position and scraped to fit correctly.
> steve




UPDATE!

Thanks to everyone who responded here and also to Dan Kemp (Hoss) if you read this.  I did in fact have the X and Y-axis gibs mixed up.  However, in the final analysis it didn't matter because the problem followed the bad gib. The X-gib was not flat and straightening it is not easy.  I took the easy way out and used a motor powered flat polishing wheel to wear away a few thousanths from both sides of the gib.  I eventually had to remove about 10 thousanths before I got an acceptable fit.  I also ordered a new gib (they're cheap).  For anyone like me who has a way to get parts mixed up see the photo below showing the three gibs and their approximate overall length.  Xand Y ony differ by an eigth of an inch so it's easy to mix them up.  Now with X & Y finished I'll get started with Z.  Stay tuned for more updates.


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## RWL (Apr 13, 2014)

I took Richard King's scraping class in December and he showed us how to straighten a gib.  You wouldn't have had to remove any metal from it.  We all think of cast iron as brittle, but it will bend and can be straightened as Richard showed us in the class.  To straighten it, put it on a surface plate (or any reasonably flat surface if you don't own one) and put a feeler gage under it to determine the two points it's resting on, and mark those points with a magic marker.  Put the largest feeler gage you can fit in the gap to see how bent it is.  That tells you how much you need to bend it.  Mark the highest spot with the magic marker.  Now take the gib to a sturdy bench (preferably metal because you'll be using a dial indicator) and rest the two outer marked points on blocks.  Put a clamp next to the high point.  Put the dial indicator's point on the high point of the gib and zero it.  Tighten the clamp until the indicator has moved about twice the distance of the gap you measured with the feeler gage.  Release the clamp and see how much the gib returns to its previous dimension.  Hopefully it will have moved toward straightness a few thousandths.  Repeat the process making the feeler gage go a little farther down than before. Release and see how much more you need to go.  Keep repeating the process until the gib is within 0.002" of flatness.  He would then scrape it to flatness. In your situation, I'd just accept the 0.002 of bend and install it.


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## angelfj1 (Apr 14, 2014)

RWL said:


> I took Richard King's scraping class in December and he showed us how to straighten a gib.  You wouldn't have had to remove any metal from it.  We all think of cast iron as brittle, but it will bend and can be straightened as Richard showed us in the class.  To straighten it, put it on a surface plate (or any reasonably flat surface if you don't own one) and put a feeler gage under it to determine the two points it's resting on, and mark those points with a magic marker.  Put the largest feeler gage you can fit in the gap to see how bent it is.  That tells you how much you need to bend it.  Mark the highest spot with the magic marker.  Now take the gib to a sturdy bench (preferably metal because you'll be using a dial indicator) and rest the two outer marked points on blocks.  Put a clamp next to the high point.  Put the dial indicator's point on the high point of the gib and zero it.  Tighten the clamp until the indicator has moved about twice the distance of the gap you measured with the feeler gage.  Release the clamp and see how much the gib returns to its previous dimension.  Hopefully it will have moved toward straightness a few thousandths.  Repeat the process making the feeler gage go a little farther down than before. Release and see how much more you need to go.  Keep repeating the process until the gib is within 0.002" of flatness.  He would then scrape it to flatness. In your situation, I'd just accept the 0.002 of bend and install it.



RWL, thanks.  This is very interesting.  Who is Richard King?  Is this an on-line course?

Best regards,

Frank


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## chuckorlando (Apr 14, 2014)

You can order is dvd's but the class is not on line. I hope he comes to Fl one day as I would take his class in a heart beat. He teaches one how to hand scrap in a machine


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## RWL (Apr 14, 2014)

angelfj1 said:


> RWL, thanks.  This is very interesting.  Who is Richard King?  Is this an on-line course?
> 
> Best regards,
> 
> Frank



Richard King is an instructor in machine scraping who gives 3 day seminars to groups of hobbyists as well as travelling to manufacturers to teach their workers, in particular to Taiwan.  He sells a video on ebay that is helpful:  
http://www.ebay.com/itm/LEARN-TO-HA...184?pt=LH_DefaultDomain_0&hash=item27dfdf0798 
You also get a copy of the DVD when you take the class.  It illustrates scraping techniques, but IIRC it doesn't cover things like dovetail scraping and machine alignment and gib straightening, things he covers in the class since the class is geared toward machine rebuilders.  He told us at the class that he liked being on this message board, but had a disagreement with management and now hangs out elsewhere.


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## RWL (Apr 14, 2014)

Actually, I should add to Richard's background.  His father was a machine rebuilder and Richard and his brother followed in the business.  IIRC, they were relatively early adopters of Biax power scrapers when they were new to the US.  There was demand for someone to teach power scraping at the manufacturers and Richard wound up with this as an add on to their business, which for him eventually outgrew the machine rebuilding part.  I believe he still does some rebuilding at his shop.  He's getting close to retirement age, so if you're thinking of taking one of his seminars, better do in the next few years.  He didn't say anything about retirement at the seminar however.


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## doncaprio (Aug 15, 2016)

I know this is an old thread. Hoping to see some updated replies.
I'm converting my G0704 to CNC. I went to re-assemble the Y axis and the gibs are too tight. They slide in nice but the last inch or so get wedged.
I've seen in previous post that the X and Y gibs are different sizes and tried them both but no go.
Is it normal that the gibs be thicker at one end than the other?
The end with the notch is about .050 larger on both gibs.

The gibs look nice and flat. When I check on a metal flat surface there is no visible gab in the middle and it doesn't look twisted.
I can't image them getting bent. When I removed them I labeled and placed them in a wooden parts box for safe keeping.

How can these things appear to grow (swell)? I know that there can be variations in thickness based on temperature.

Are these gibs hand scrapped? 

Whats the best way to repair? Do I buy replacements or try and grind/sand to fit?

Any help would be greatly appreciated.


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## higgite (Aug 15, 2016)

doncaprio said:


> Is it normal that the gibs be thicker at one end than the other?
> The end with the notch is about .050 larger on both gibs.



Yes. The gibs on a G0704 are tapered. They have to be inserted thinner end first. The Y gib is inserted from the front side of the mill. See page 41 of your manual for how to adjust it. Unless they have been bent or otherwise damaged, they shouldn't need repair.  Hope this helps.

Tom


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## doncaprio (Aug 17, 2016)

After some more research I did learn that the gibs are tapered. I also broke out the manual for the mill however there wasn't much in the gib section. Seems like every source I run across the gibs should just slide in and then adjusted with the screws.

This is a shot in the dark but I just ordered two new gibs (X and Y) from Grizzly. We'll see how that turns out.
I'm also going to call tech support in the morning and see if they have any ideas.


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## coherent (Aug 17, 2016)

Check your old gibs using a piece of glass to ensure they are straight. They are tapered as mentioned and must go in the correct direction. Remember the adjustment screw on the far (narrow) end keeps the gib from wedging in too tight and binding between the ways. The way is also tapered so that the way and the gib combined equal a flat equal sliding surface when installed correctly. As mentioned you must have the correct gib on the correct axis and they must be inserted from the correct end/direction narrow end first. In addition the rear/back adjustment screw (at the narrow end) should be installed and adjusted so the gib cannot go in far enough to cause binding. Initially keep it adjusted in a bit extra until everything is installed, then loosen the rear (narrow end) a slight bit at a time while tightening the front until you have a happy medium between no play and free movement of the axis. Additionally don't over tighten the adjustment screws or what happens is you squeeze the gib between them causing it to bow, bind or possibly bend the gib. I initially also had problems reinstalling mine after a CNC upgrade, but once I did a little research and had a better understanding of how they fit, operate and which direction they went in, it was a simple process to install and adjust them. As usual (at least for me) it seems the simple things can cause the most problems and the gib installation and adjustment can qualify. Hope this helps. Good luck!


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## doncaprio (Aug 20, 2016)

I've been leaving out both adjustment screws thinking it should slide in ok without them.
I'll try installing the screw for the narrow end and see if that makes any difference.
Thanks for your comments.


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## higgite (Aug 20, 2016)

doncaprio said:


> I've been leaving out both adjustment screws thinking it should slide in ok without them.
> I'll try installing the screw for the narrow end and see if that makes any difference.
> Thanks for your comments.



Here's a good visual of how to install and adjust the X-axis gib on a G0704. The same principle applies to the Y-axis gib.

Tom


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## underwood760 (Oct 10, 2016)

doncaprio said:


> I know this is an old thread. Hoping to see some updated replies.
> I'm converting my G0704 to CNC. I went to re-assemble the Y axis and the gibs are too tight. They slide in nice but the last inch or so get wedged.
> I've seen in previous post that the X and Y gibs are different sizes and tried them both but no go.
> Is it normal that the gibs be thicker at one end than the other?
> ...


just had the same problem , had the gibs reversed , make sure you are putting them in from the wide side  as the are tapered ! I also noticed that you ordered gibs from grizzly , I brke one and had to make a new one , you are going to need a grinding table to do them accurately , I cut one to length,  ground it on my bench grinder. it is a real pib and you have to make sure you grind them flat , end to end until it silde all of the way through the gib slot , then you can cut it to length with a hack saw or whatever you have , a mill with a face cutter can do it as well , if you have access to one or you can get a shop to do it ! But for me I would grind and try it , over and over  until it goes in smoothly ! Good luck !


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## doncaprio (Oct 11, 2016)

Update.
I ended up masking a replacement gib from the ones I ordered from Grizzly. It's wasn't all that bad after all.
I slid it in and marked the front and back then cut it to length with a hack saw. I was also able to cut
the notch with a hack saw as well. Seemed to fit well and I could adjust it with the adjustment screws.
This may not be the perfect job as I have no real idea what the proper procedure is but it worked.
The saddle is nice and tight.
I still have no clue how/why the original would not fit. The gib tapered end was over sized about .010.
My only guess is that I may have dropped it and the impact bent it.


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