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View Full Version : Power feed problems with VICTOR 618EM (Hardinge)



YankeeMetallic
08-09-2006, 01:19 AM
I have been having a problem with my Victor precision lathe.
Recently I was doing a threading operation on many parts. All of a sudden the lathe came to a grinding abrupt stop. The spindle would not turn with the thread knob engaged (NOT good!). I opened the thread gear box and a bunch of teeth fell out. I took it apart and found 4 gears and a splined shaft had been stripped of about 30% of their teeth. I purchased the replacement parts (Taiwan!), new bearings and six weeks and $800 later I am up and running. My best guess is that my carriage hit something and stopped the feed to the left, or that there was a damaged gear just waiting to go.
Anyway, on to an increasing problem.
My lathe uses a DC motor for the power feed on the X&Y axis. In the past few months I have noticed that the carriage does not like to power, or hand feed to the right after it has warmed up. The power feed to the left works fine at any feed setting. The feed to the left is free for the first 1/2 hour of work and then slowly gets harder and harder to turn by hand wheel, and the power feed stops, probably do to the increased resistance.
I removed the DC motor and checked for its feed performance in each direction under a load. It performed fine. I checked what gears I could see through the open hole where the DC drive cog meshes with the cogs in the carriage. There were no damaged teeth. With the DC motor out it did not ease the resistance of the carriage when moving it with the handwheel.
The Y powerfeed performs fine. I have a DRO installed for both axis so I removed each linear scale without any change in the X axis resistance. The rack and pinion gear for moving the carriage in the X axis is not damaged and is clean of debris. There is not outside resistance to the carriage (DRO cablesm lubrication hoses, taper attachment).
I have removed the wipers and checked for bed debris, cleanliness. It is all fine. The bedway well lubricated. None of the thread stops are in the way, the carriage lock is not engaged, and the threading half-nuts are not touching the lead screw. The power feed handles move freely throughout their ranges. The X Axis gib is not too tight but I cannot figure out how to adjust it.
I am running out of things to check. I purchased a new manual for this machine but it does not offer anything in the way of troubleshooting (Frankly it sucks. It doesn't even have gear set schematics for gear sets A,B,C & I. but that's another story). I called tech support through Victor's Los Angeles contractor "Machinery Solutions". Their East Indian tech guy ("John") cannot even turn on a lightswitch, and he transferrend me to a Taiwanese man ("Ken") who couldn't speak enough english to even get started!
I am thinking the slipper clutch for the X axis may be the culprit. The manual only addresses the clutches as, "...the clutches are set to handle any work performed on the lathe." The year of manufacture is 1992. The maual has a very vague diagram of the clutch setup or how they work.
Does anyone have any experience with the clutches in a Victor or Hardinge HVLH? Or any suggestions of what the problem might be? How do you adjust the jibs on this machine?
Any input would be appreciated.

Millman
08-09-2006, 01:30 AM
{{How do you adjust the jibs}} You have to be joking or jacking around?? Some people just don't deserve what they have.

YankeeMetallic
08-09-2006, 01:55 AM
{{How do you adjust the jibs}} You have to be joking or jacking around?? Some people just don't deserve what they have.
Okay... besides MILLMAN, the Gib question is out there for this lathe. I've attached photos of the right side of the carriage. I know what a jib is, what it does and how to adjust them on my Lagun mill, drill presses, surface grinder and Nardini lathe.
When I take the wipers off I can only see then end of the jib on the left side of the carriage. I cannot see any locking or setting screws for jib adjustment on the right side. I have had this lathe for less than a year so I am asking for assistance, not sarcastic meaningless post counters.
MILLMAN, instead of sitting in front of your computer with a fistfull of weiner and posting, just to get another post count, don't bother posting on my threads unless you can offer some suggestions to the answers you probably know.
Anybody else have a useful suggestion?
http://i41.photobucket.com/albums/e254/YankeeMetallic/Lathegibs002.jpg
http://i41.photobucket.com/albums/e254/YankeeMetallic/Lathegibs001.jpg

Millman
08-09-2006, 02:01 AM
That's funny and you have sympathy. There are basics..that you have to learn before you are allowed to work on or Adjust any mechanical device. Lazy people have to advertise their stupidity on a public forum. You are looking for an easy fix, or a quick answer, which proves you are too lazy to learn the basics and YOU do not deserve such a fine machine.

miker
08-09-2006, 02:06 AM
deleted poor taste.

Millman
08-09-2006, 02:12 AM
Some people in Australia are special..too bad you are not one of them. You're just lazy.

Elninio
08-09-2006, 05:29 AM
Just tighten the gib screws until there is the least ammount of play possible, trial and error and check w/ your dial indicators. Make sure the carriage can move smoothly across the bed w/o stalling

DR
08-09-2006, 09:24 AM
First off, lets' get the terminology right.

It's gibs not jibs.

Also, on a lathe the axis of the carriage moving right/left is the Z axis. The cross feed axis is the X axis. (on a mill the X axis is right/left, Y would be in/out).

Your problem sounds like a tapered gib that's loose. Tapered gibs that are loose will tend to self tighten (bind the carriage travel) in one direction and be free (non-binding) in the opposite direction. The taper of the gib can cause a very strong wedging action in one direction if something is wrong. This theory assumes you have tapered gibs though.

In your picture there's a hole in the lower part of the wiper cover that might be access to a tapered gib adjustment screw.

If you do have tapered gibs, the gib itself could be broken at the end where the screw actuates it. It's too hard to describe how the adjustment screw works on a tapered gib to describe here, but if you could look at it, the operation will be obvious.

The binding of the carriage could have also accounted for the stripped gears when threading. Most machines have some sort of shear pin that breaks prior to stripping gears so it's hard to say though.

If your manual sucks as badly as you say you may want to get a copy of a Hardinge manual. The usefulness of the Hardinge manual will depend on how exact a copy the Victor is of a Hardinge machine. For some of the Hardinge machines they have multiple manuals, a simple one for general operation of the machine and one or more for trouble shooting/repair. A call to Hardinge will reveal what they have in the way of manuals. (Be sure not to tell them you have a Victor lathe, they won't like that). Ebay might be a good source or manuals once you determine which one you need.

JCHannum
08-09-2006, 11:00 AM
DR may be on to something, a tapered gib is normally adjusted by opposing screws. If the gib is broken, or one screw is missing or misadjusted, the gib can float in one direction, causing the problem described.

The lower hole in the way wiper holder would be the first place to look. If there is one on the other side of the carriage, that is probably where the screws are located.

There is a good possibility this was the cause of the geartrain failure as well if there is no safety device such as a shear pin or fiber (shear) gear present.

LarryinLV
08-09-2006, 01:00 PM
Nice machine...wish I had one.

Look for pressure marks (rubbing) at the point where the table starts to bind. The gib (some pronounce it jib) exerts pressure on the front face and if it is binding excessively there should be evidence. Is there also a gib on the back side? I agree with the tapered gib hypothesis, but there should be some hardinge users here to confirm..If not go to the Hardinge lathe forum.

Check your table lock to ensure it is not grabbing as you move the table. When unlocked there should be free movement of the lever. When the table binds is there free movement?

From your picture there isn't much room from the lead screw to the half nut at the top. probably just parallax, but hey, make sure nothing is rubbing. Gib screws and lock nuts on the apron are clearly visible, What do they do?

If you can't fix it give it to me. .

DR
08-09-2006, 01:36 PM
Here's a page from an Hardinge manual regarding adjustment of the tapered carriage gib.

http://www.csparks.com/hardinge/Manual/Page24-25.jpg

Unfortunately, this carriage doesn't look exactly like the Victor one. The Hardinge gib pictured is the type that adjusts from one end only, it doesn't use opposing screws like some tapered gibs.

pcarpenter
08-09-2006, 01:47 PM
The gib screws and lock nuts I see (on the side of the carriage in the picture) look like the are for the sliding half nut "ways".

As several have said, a gib floating around will wedge one direction and float loose the other. If that uses tapered gibs for the carriage to way fit, the adjustments are probably under the wiper plates--which you have checked. A tapered gib has the luxury of being adjusted from one end with a single screw. You could have a single screw mounted elsewhere that operates a lever arrangement that pushes the gib in its socket, so don't discount that the adjustment could be someplace odd.

Or...it could be a flat gib with a series of adjustment screws....those could be on the face of the carriage or even underneath....which would be a real treat.

Paul

LarryinLV
08-09-2006, 01:50 PM
DR,
I was just looking at that exact page and about to post it.

Great minds...and all that.

I believe that it confirms that the gib adjustment is probably in the open hole we see. Since we do not see the screw head clearly, it is possibly screwed in way too far..

YankeeM,
The site DR posts is the Hardinge lathe manual. Go there and correlate your Victor adjustments with the Hardinge adjustments. Your lathe will thank you for it.

Rustybolt
08-09-2006, 05:52 PM
Let us know how it turns out.

nheng
08-09-2006, 07:21 PM
One way to adjust a tapered gib is to remove it, clean the gib and dovetails, insert it with fingertip pressure only, adjust the the rear (or thin end) screw lightly against the gib, adjust the front (or thick end) against the other end. I follow up by lubing the slide and then using a DTI to check side to side play, further adjusting for 0.0005" to 0.001" range. This has worked well for me (on my Harrison).

It's important to make sure that the gib has no bow to it and that the screws are not overtightened, causing a bow.

Den

YankeeMetallic
08-09-2006, 08:08 PM
Thank you gentlement for your assistance. I learned a lot from your comments, including the X&Y axis are opposite on a lathe.
A loose tapered Gib does make sense and is likely the problem.
I spent the major part of today making phone calls and internet inquiries trying to get a parts diagram of the carriage Gib. I DID get a parts diagram, although a it is a bit grainy, of the Gib for this Victor lathe.
It does appear that the hole in the wiper is supposed to house 2 screws, an adjustment and a lock screw. It is different than the pics of the Hardinge though. I have inserted a flat blade and phillips screwdriver deep into that hole (3+") and all sizes of allen wrenches but nothing grabbed. The hole is too deep to see inside. I will be taking it apart tonight when it gets cool to try and find the problem. Missing parts is the first problem, it wouldn't be obvious to adjust a part if it is not there to start with.
I will take pics and keep notes so when I solve this problem it may assist other Victor owners with the same problem.
I will post results tomorrow.
I am a self employed machinist by necessity, not by trade. I did something else for 15 years previously, so at age 39 I have a lot of knowledge to catch up on in the machinist field.
Thank you again-

YankeeMetallic
08-09-2006, 10:57 PM
I fixed the power feed problem tonight. I removed each wiper. The Gib locking screw was missing from the right side of the carriage. The hole that I was sticking tools through trying to mate up with the gib adjusting screw was actually a hex hole, countersunk adjustment screw that had been stripped to a circle. It had been tightened as far in as it could possibly go, and then obviously stripped. How can you strip a hardened hex adjusting screw with a thru hole?
I used a brass drift and tapped it in until it created enough friction to screw it out. It took several taps and turns until I got it out. The Gib adjusting screw was obviously home-made out of BRASS! I removed the tapered gib for cleaning. The ways-side had a coating similar to teflon. It was covered in hardened grease and small metal chips. I blew the gib passageway out with brake clean and a rats nest of stringy aluminum, nylon and grease fell into the chip pan. I dismantled the carriage lock and cleaned the crap out of that as well. I made two new gib adjusting screws out of large surplus shoulder bolts and mildly hardened them. I lubed up the gib and replaced it using my home made adjusting screws. I adjusted the gib moving the carriage back and forth and indicated it in to 4 tenths. I replaced the wipers not realizing they created more friction. I had to re-adjust the gib taking into consideration the friction that wipers created. The carriage now turns easily in each direction by hand and works smoothly under power feed at any setting. The carriage lock handle now has a much greater range of movement to lock, which suggests that the crap in the locking mechanism was also slowing down the carriage. The gib lubrication port covered by a countersunk hex screw on top of the carriage was also clogged. The DC powerfeed motor also runs cooler since it is not working so hard to move the carriage.
I think there were many contributing factors into this malfunction. All of which were suggested by most of you. Between fixing the stripped cogs in the threading gear box, and this repair, I am getting to know this machine inside and out.
Thank you for your assistance and perhaps I can return the favor to another novice in the future. This VICTOR lathe is great piece of precision machinery and I am happy to have it working to its full potential again (making $).
Yankee-