How to adjust or tighten up gibs and ways on a Wells Index vertical milling machine. Similar methods can also be used on other types of milling machines.
Did my apprenticeship in a shop with Wells Index machines 30 plus years ago. Nice to see some of these machines again. Kind of a trip back. Of course you did not get out of the apprentice shop without being able to adjust, tram, and perform general maintenance on the various machine tool. Checking and repairing surf machines also fell to apprentices. Thank for the trip back.
Keith, thank you so much for posting this video. I remember watching it when you first posted it but I didn't have a mill at the time. Now I have been having issues with my new mill and this gives me a lot of valuable information on how to get it set up correctly. Thanks for all that you have done for us.
I have a small mill (seig SX3 DIGI), when I checked for slop in the ways with the table fully extended to one side there was not any noticeable free play. However if I bring the table to the centre position so the weight is balanced either side of the saddle I noticed considerable slop in the table and saddle gib. I believe on the small mills that the weight of the table hanging on one side artificially takes up the slop in the ways, bearing in mind that with these small mills you can't put lots of weight side to side as you will twist the frame and or stand etc. So on smaller mills I would recommend checking for free play with the table cantered on the saddle. Excellent video Keith as always.
Thanks Keith, this video has been a huge help for me. I also own a wells index 847 vertical mill, so all of your videos about them have been a great help.
Thanks again Keith... watched this again today and followed it to tighten up the gibs on my Index 845! I found 0.006" in my X axis that now makes for less chatter. Cheers! Jeff P
Shop I served my apprenticeship in had a rule for Bridgeport type mills no end mills larger than .500 no face milling no drills larger than .500 no using quill feeds for drilling. All rough milling was done on the heavy KT mill holes were drilled to .500 then made to larger size on Radial drill press . Bridgeport's were to be used for precision work only . Very little backlash, head was almost never out of tram.
Sweet! Excellent video. I picked up a T&C grinder in multiple boxes. As I was putting it back together, the gib adjustment was shadowy in my mind at best. This video made short work of the fog! Thanks for passing on your knowledge.
One thing that can be done for machines that have excessive play, throughout the center of travel, is to place shims of appropriate thickness between the gib and the base piece, not the movable table, knee, etc, at the exact center of the gib, and, on machines with a large amount of total travel, thinner shims, of appropriate thickness, mid-way between the center and the area where the machine falls back into tolerance. Ordinary steel shim stock works quite well for this. You will sometimes encounter this problem with surplus production machines that have more than 10 years of continual use on them. If you are lucky enough to get a fairly new machine, that is in tolerance, you can extend the useful life by varying where you place the work along the travel of each axis - as practical. This will give you a more even wear pattern. The one exception is the vertical, or "Z" axis where you do not want any more pieces than absolutely required to hold the cutting tool. This shimming practice can really spruce up the vertical axis as well. Out of tolerance motion really increases chatter and accelerates wear on the cutting tools. Inferior finishes are not the only problem with excessive play in the ways of a machine. Many times this simple shimming operation will bring a machine, with excessive central wear, back into tolerance throughout its length of travel. As the gib does not move, the shims will stay in place quite nicely, although you may occaisionally experience a slight bit of tightness at the ends of travel depending upon how much shimming you had to do to accommodate the amount of wear - as the wear will generally affect both the exterior and interior dovetails of the ways. As long as this is not excessive at the ends of travel, it will not significantly affect the machine's operation, and is a darned sight less expensive than disassembling the machine and sending the affected castings to a shop to have the ways reground - or living with substandard work and shorter tool lifes.
This sounds like an excellent work around for an older worn-ways machine. We have a Model H Milwaukee, (1948±). It even sounds clunk-clunk wiggling left table end in and out! I think it's over .050" slack at the table end. The mill must have waded through a huge tonnage of workpieces.
Just now watching this video, Keith. I just picked up my first mill today...1955 Series 1. Got it home and got to cleaning it and grabbed the table on either side and pulled and pushed it (rotating it on the axis of the spindle) and I almost vomited. I have a large amount of play in the table and from the look of it, its in the cross feed ways. I am hoping I can correct it with the gib. I just shut the lights off and came in the house when I saw that. Now its a marathon tonight of watching videos on adjusting sloppy tables and yours is first!
+Brian Streufert Good luck with it! If yours is a Wells Index, keep in mind that they are still in business and I have called them for advise before and they were glad to help.
Lucked out Keith.....I couldn't just sit inside and wonder if I bought a boat anchor. I went back out to the shop, ran the table over, took the y-axis way cover off to expose the adjusting screw and....it was completely loose. Tightened it up and now there is no perceivable play. I'll get an indicator on it in the next day or two and get it all indicated as you did. Load off my mind though I tell you that!
Very nice video. I am completely retrofitting my Wells Index 823... and didn't know how to set these... I really didn't know about the lock screw... so I very grateful that I fond the video! If you want to see my progress... The Milling Machine Move - May 2014 Thanks again!
Best video yet. One question. When adjusting my z-axis on my Bridgeport moves a little bit under .001" if I go up or down, cranking the lever. Can't figure out how to get this out. Pushing the gib further down doesn't help. Thanks again for the great video.
You are correct that I should have put the indicator on the bottom half of the table gib rather than on the table itself. This would have potentially compounded the error between both and saddle and table misalignment. However, in the case of my mill, I was still well within tolerance for just one of the gibs. If things were way out, the way I did it would have made it more difficult to determine where the error was coming from. Either way, the end results are that my mill is in tolerance!
Keith, thanks for the info on maintenance. It's an area not often covered, and something newbies like me who are interested in setting up machines for hobby use really need to know. Really well done on the views under the table and saddle...and nice editing on fitting those shots in. Very professional. So far the closest I've come to an adjustment like that was on an import cross slide vise for my drill press. The adjustment on that was much less sophisticated...just three screws with locking nuts pressing on the gib from the side. I didn't try to measure tolerance...just wiggled it a bit until it didn't. Maybe I'll go see how well I did now that I have some clues how to do it! -- Mike
Doesn’t putting the indicator on the saddle and indicating on the table like that give you the slop in the x and y gibs? I’d think you’d want to indicate a little lower to isolate the slop in the y.
The adjustments are independent of one another, but as a rule of thumb, I usually do re-check everything once I have gone through everything just to be on the safe side.
Bridgeport mills do indeed have a locking screw for the gib adjusting screw. It is located at the rim of the adjusting screw and prevents it from turning. The adjusting screw moves a ring which sets in a notch near the end of the gib.
***** Keith, After close examination of the standard parts drawings, I see that my mill has been modified by a previous owner to include a locking screw. So, please disregard my previous comment. AND, thank yo for the excellent videos!!!
great video Keith! We're faced with this delima right now with the saddle gibs on a KT #6CSM mill. It's an old old machine, but still a really good machine overall. Some really small chips managed to somehow get up underneath and past the front scraper.
Thanks for the thorough explanation and also going over all the terminology. I am getting a mill in the next couple of months so i'm watching as much as I can til then, so I have somewhat of a clue when I get it. I'm considering a G0755 . Maybe do a vid on what a noob should get, along with a machine. ...Subbed, alot of great channels out of Georgia (weldingtipsandtricks) and Thanks again Sir !
I could be wrong, but the .001" tolerance in the table (as it travelled from end to end) may be from its weight? .000" right limit, .001 middle, and .000" left limit? Or wear.
A 200 thousandths cross feed is also 5 MM within .003. All you have to do is change the dial and it's metric. If we cut metric threads, we are still going to program the machine in inches to do it.
I just replaced the variable speed belt on my 9x49 Jet mill. Took two of us and a forklift. I have the manual but it left out a couple of important steps. It would be really difficult with out some sort of lift.
Hi Keith, Again a very clear instruction video. However I noticed that in all three axes you only took one measurement. Would you not have got a better idea of any wear present, by taking at least three? This would prevent binding if you'd taken your reading in a high wear position or vice versa. Regards. p.s. Please keep them coming.
Easy to do on a manual machine where you can crank the handle and feel it as you adjust. On a vmc that is cnc only without hand crank handles it’s a different story. It is very hard to adjust a 1000lb z head when you only have a button 5 feet away to press and closely watch for gib movement. Curious if there is a better technique to do it.
Thanks to Keith for the video. So, is the spec to be literally zero? I get about +/- 0/001" on mine, and it springs back to wtihin about half of that, but not all the way. Any input very welcome.
Hi Keith, hopefully you see this comment or if anyone with professional experience could reply, it would be very appreciated. I am wondering how much play you get on the knee with the indicator set up like in this video when the knee is raised and lowered (so dial on the knee bed to the main body bed)? I get about 0.05mm (0.002 inches) which seems excessive? It is a new machine and after adjusting the knee gib, these seemed to be the best results. I have tried contacting the suppliers but they do not have any info on this. This could just be due to the knee weight being transferred (so actual flex in the body) so the only appropriate test may be the one in this video?
When measuring the sadle gib (spelling ???) the base og the dial is on the knee and dial finger is on the table ... this way I think you will get BOTH the table gib AND the sadle gib mis-adjustment - right ?
Great video. One question, though. Isn’t the measurement amplified by the length of the indicator holder arms, particularly when checking the knee? Seems like it could lead to over-tightening the gib.
It's more the location the indicator is touching, as putting it further from the center line would cause the table to sweep a larger arc as pressure is applied. However, I believe the manual for this machine specifies where to place the indicator to take the readings, in addition to the maximum value of 1.5 thousandths.
Its not as used on the ends of the table going to be tighter there the mid should be checked as well. im looking to do my tormach cnc (at least chk it). Its been my experience the Bridgeports are normally more used in the middle of the machine.. just an option. The cnc check is so different. i think your way with the indacator should be much more accurate then the way they do it. i still have to check it it loses steps..peace
I have never had to adjust mine, so I am not sure. There is a manual for this machine that you can download from the VintageMachinery web site - search for Wells-Index, go to the Publications tab, and select "Manual and Parts List for Milling Machine Models 747, 747VS, 847, 860". You can also give Well-Index a call, they are still in business and still making that mill. I have talked to them before and their tech support is great! (231) 759-0950
