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JeffKranz
10-12-2005, 03:40 PM
I just purchased a travadial model 6A. This one has a small metal dial for the .100 movement and the large dial for the .001. I know you can rotate the large dial to set to "0" but the $64,000 question? Can you reset the metal dial to "0"? I tried to lift it, push it, and even tried to turn it while holding the wheel that contacts the lathe. We have the newer model that resets "0" when you rotate it counter-clockwise.

Thanks

Jeff

rockrat
10-12-2005, 09:14 PM
There was a fellow, the Doctor, that was rebuilding these. He was going to write a bit on the steps needed to clean up travadials. Since I havent seen anything, I'm guessing he might have submitted it to HSM for publication.

As for the little dial hand, I dont think that it is possible to move it with out using a watch hand puller or something similar.

But then again, I never tried.

rock-

JCHannum
10-12-2005, 09:45 PM
<font face="Verdana, Arial" size="2">Originally posted by rockrat:
There was a fellow, the Doctor, that was rebuilding these. He was going to write a bit on the steps needed to clean up travadials. Since I havent seen anything, I'm guessing he might have submitted it to HSM for publication.

As for the little dial hand, I dont think that it is possible to move it with out using a watch hand puller or something similar.

But then again, I never tried.

rock-</font>


He posted it here, and did i very good job of it. It should be submitted to Village Press.

Here it is; http://home.comcast.net/~marconi30/Trav-A-Dial/GD-46/GD-46_Repair.htm



[This message has been edited by JCHannum (edited 10-13-2005).]

The Doctor
10-13-2005, 12:02 AM
A good job? I still haven't finished that page completely. If you want to check out what I have done, here is a clickable link.
http://home.comcast.net/~marconi30/Trav-A-Dial/GD-46/GD-46_Repair.htm
I have also added a PDF of the installation manual, fairly decent quality, here is that link.
http://home.comcast.net/~marconi30/Trav-A-Dial/Trav-A-Dial.pdf

Please note that the model I repaired was a GD-46, although I believe internally it is probably identical to a standard 6A. as for your variation of the 6A which reset to zero by turning counterclockwise, I'm not familiar with that at all. On the GD-46, and on the 6A that I have, the .100 dial is very easy to adjust the zero on. Here's how that works. The dial itself is not directly secured to the shaft, it fits kind of loosely on a bushing and there seems to be some kind of spring and fall to give it some tension. The bushing is held to the shaft with a set screw, the shaft, of course, is part of the actual measuring wheel. To change the zero position, the measuring wheel is simply held still while you turn the knob, it can turn fairly easily on the bushing and allow you to set to zero wherever you want. Of course, when the unit is mounted on the lathe, you have no need to hold the wheel. If the Trav-A-Dial is mounted correctly, it's pressure against the edge of the lathe way will be quite sufficient to hold it in place while you make this adjustment. I can only see two possibilities here, one is that somehow the dial is stuck to the bushing, either by corrosion or somebody used too long of a set screw, or your version of 6A is completely different than what I am familiar with.

Try this, rotate the knob and look for the hole were you access the set screw to remove it. If you can see a brass bushing through the hole, you have the same style I do. If all you can see is a set screw, loosen that and remove the knob. Is there a brass bushing in the end of your knob held by a circlip? If yes, yours is apparently stuck and you need to figure out how to get apart. If not, you have something I am not familiar with, and you better call the experts. The units are still made by southwestern industries, here's their URL.
http://www.southwesternindustries.com/swi/

I promised a fellow on this board I would also do a write up on making up a mount and installing the Trav-A-Dial on my Logan lathe, which I still plan to do sometime soon. The fact that I just recently picked up a monarch 10ee with a digital readout is not helping that project along http://bbs.homeshopmachinist.net//biggrin.gif But rest assured I do plan to write that, as well as a disassembly and repair guide for the 6A I have, which is very gritty and definitely needs an overhaul.

Till next time
Ed

JeffKranz
10-13-2005, 06:16 AM
Ed,

Thanks for the information. I can see the brass bushing through the hole in the dial. I think the dial is stuck on the bushing because I can't seem to rotate the dial without the large wheel that contacts the lathe turning. Since I don't have it mounted on a lathe, I don't think I have the tension to hold it in place. I'm afraid to use brute force because I don't want to break anything. Should you be able to hold the large wheel with your hand and rotate this knob?

Jeff

The Doctor
10-13-2005, 12:34 PM
Jeff, you should not need to have it mounted on the lathe to make that adjustment. The knob could easily spin on the bushing with just your thumb and forefinger, and you should not be straining yourself doing it. If everything is OK, a small child would be able to do this, therefore I assume that you have some stickiness. Hold the measuring wheel as tight as you can with your foam, and try to turn the knob forcefully. If you can get to the set screw, just remove the knob and work on it as a separate peace. When you take it off, be aware that there may be some shims on the end of the shaft to set the clearance between the knob and the housing, do not lose these. Once the knob is removed, mounted to a piece of steel shaft the appropriate size, and clamp that in the vise. Now you should be able to rotate the knob oh it's sufficiently loose, spraying penetrating oil quite liberally as you go. If you can't get to the set screw to remove the knob, I'm afraid I can offer you a whole lot of help. If that is the case, all you can do is try progressively harder to hold the wheel as you try to get this knob to turn. The normal force of the wheel against the machine way is about 35 pounds, I think it could easily stand well over a hundred without damaging the bearings on the shaft. So perhaps a strong friend could push the Trav-A-Dial against a smooth metal surface while you try messing with the knob. If it's really stuck, the problem you will face is finding a safe way to prevent the wheel from turning as you try to rotate the knob. In a very worst-case, you may have to take the Trav-A-Dial apart and try holding the wheel in a lathe chuck, perhaps. I would only resort to something like this as a last-ditch effort, as you may well put some deformity on the wheel, which will basically be the end of your Trav-A-Dial.

If you have any questions I may be able to answer, please don't hesitate to ask. However, I think you now see how it works and you now understand the problem, I hope with this information it can work out to a happy ending. A Trav-A-Dial is probably one of the greatest addition you can make to your lathe, with the possible exception of a DRO.

Ed

ljchipmaker
10-13-2005, 02:41 PM
First, I am new to this forum, but have enjoyed reading it for some time now.

I am a lab-tech in a machine shop at a community college which shares its facilities with local high schools TBA program. Yesterday the high school lab-tech and I were forced to attempt to clean and maintain a Travadial. From all the info I could find on it, it appears to be a model 6-A, but can only speculate. The installation instructions are exactly the same as the ones posted by "The Doctor". The case housing the wheel and gears are in what appears to be pressed together housing, with no screws to allow for easy disassembly. It suffered from the same thing mentioned in the other post, it would only rotate one full turn in one direction, then lock up, and then could be reversed and only returned to its starting position. After weighing our options we decided to try to flush the housing the best we could alternately with mineral spitits and light weight oil; instead of attempting to try and pry the housing apart. We were amazed at the amount of chips of all types and sizes which came out of the housing. After repeated flushings we were still unable to get it to go anymore than the one revolution. So we decided to force the issue, as the travadial was useless to us as it was and we were suffering from a disapperance of patience, so we attempted to force the wheel past the sticking point. It worked. We then continued to flush the housing and removed more chips until it began to operate very smoothly. We concluded that a chip must have been wedged in one of the teeth on one of the gears and was not allowing it to rotate beyond that tooth in either direction, and that we either dislodged the chip or broke a tooth on the gear. As it seemed not to skip or bind we concluded the chip had fortunately been dislodged.

It appears as though it would have been better for us to wait until this afternoon to try cleaning it after having read these posts. During our cleaning attempts we used compressed air to aid in the removal of the chips. After re-installing the travadial back on the lathe and replacing the bezel, we noticed that the bezel for the .001" dial was slipping and the zeroing dial would not rotate freely due to (I assume) possibly other chips interferring as a result of using the compressed air and relocating them in the dial linkage or gearing. After working the dial repeatedly and lubricating, we were able to get the bezel to rotate the dial, but not as freely as the others in the shop.

So my question is this, is the housing on this model supposed to come apart?? if so how?? And, how would you recommend cleaning this particular model?? as we have several more of them which I am sure will also need some maintenance in the future. Any info would be a great help.

LJ

JeffKranz
10-13-2005, 05:28 PM
LJ,

I'm sure the doctor will chime in but I'll give you my .02 worth. I did manage to move the dial by holding the large wheel that contacts the lathe. I think I was just being to gentle. It is not mounted on a lathe since I don't have a bracket (dovetail device). I can make a bracket for the lathe but this dovetail bracket will take some extra work. If you have a 6A I think it is black and on the underside you will see 6 holes filled with epoxy (black) and three holes in the center of the dovetail filled also. You will need to remove the epoxy to remove the screws. I'm not sure on what is behind the three in the middle of the dovetail so I hope the DR will chime in. Mine is pretty smooth but has a few rough spots and probably would remove the case and clean if I really knew how to re-install everything back once I tore it apart.

Any chance you have an extra dove-tail mount?

Thanks,

Jeff

The Doctor
10-13-2005, 05:34 PM
As far as I know, there has never been a Trav-A-Dial which is pressed together. The later models, such as the 6A are held together with screws that come in from the backside. The screws are in exactly the same places they are on the GD-46, except that coming from the back. If you look on the backside, you will see six indentations around the edge. What they do is they put the gauge together first, then they cover up the screw heads with the epoxy so you can't take them back apart. There are also if you indentations in the center which are filled with the epoxy, these are the adjustments for tension on the bearings. Do not scrape the epoxy off the three bearing adjustments, you really don't want to fool with those. As to the other six, somehow you need to remove the epoxy and then the screws, I believe the rest comes apart just like the GD-46 model.

As for the way you serviced this one, I see two problems. One is that you very well may have damaged the gear by forcing it, although you may also have simply gotten lucky and had to chip pop out. The other problem is that you cleaned all the oil out of the bearings by flushing it with mineral spirits, and they are now running dry. You need to disassemble this Trav-A-Dial properly, do an even more careful cleaning of the gear teeth and bearings, lubricate everything and reassemble. Be careful of the shims behind all the bearings, also be sure that you correctly preload the gear train as you put it together. If you have not damaged the gear, it will be good as new. If you have, and it still works, I guess no major harm done there either. If you get it apart and sort of get stuck where you don't know how to proceed, just drop me a note. I will then hurried into my disassembly of the 6A and figure out what you need to do to get it back together correctly. I'm planning to do this eventually anyway, but I will push the schedule ahead if somebody will benefit from it.

Ed

BTW, Jim Caudill, if you are reading this I sent you an e-mail last night. If you have not received it, drop me an e-mail.

JeffKranz
10-13-2005, 09:26 PM
Ed,

The travadial I have has a new foam gasket but should there be a metal wiper that go around the wheel to keep chips & crud out?

The Doctor
10-13-2005, 10:42 PM
Jeff, let me try to answer your two questions. First, as far as the Mount goes, I don't know anybody who has a spare. In fact, somebody offered me the mount free for mine. And while were talking about mounts, let me inform you there are two different types. The older type, which seems to go with the GD-46, seems to be designed so that the Trav-A-Dial can slide in it with relatively little friction, but has no play back and forth. On these, there is a thumb wheel operated tension or that pre-loads the Trav-A-Dial against the lathe way. On the later mounts, the Trav-A-Dial fits rather snugly in amount, and has sort of a U-shaped tensioner which slides it inside the mount. Once it is tensioned, the mount is supposed to grip it tightly and not let it move. On this style of mount, the Trav-A-Dial does not move to take up surface irregularities, the mount itself is spring-loaded and is designed in such a way that can flex forward and away from the lathe surface easily, but is completely immobile in the other directions. In my opinion, this is the better type of mount to get. The folks at Southwestern industries refer to it as a flexure, if you cannot find one used you can call them and see what they sell a new one for. I'm betting somewhere between $50 and $100, and if you've ever seen one you will understand it being so expensive. I can post a few nice close-ups of it if it will help you any.

As to the steel spring scrapers at the sides, my GD-46 has them, my 6A does not, nor does it seem to have any method of mounting them. When you are making up your mounting bracket, you may wish to consider leaving provisions for a spring-loaded felt wiper on each side of the Trav-A-Dial, to add a little extra cleaning over the stick on foam strip that goes on the dial itself.

Ed

ljchipmaker
10-17-2005, 09:13 AM
First, Thanks for all the info, it is a great help. We will be pulling the travadial apart and re-lubricating the bearings today. We have printed out the maintenance descriptions and filed them for future reference. I will get back with you if we run into problems.

Jeff, some of our units have the metal wiper you are referring too. The exception is the ones on our machines are made of brass, and two of them have wore through and became ineffective and have had to be removed. These slipped over the housing and were held in place by spring loaded fricition applied as a result of their shape. They had a radial bend to there shape.

Thanks again, LJ

ljchipmaker
10-17-2005, 03:59 PM
OK, Travadial was dis-assembled, re-cleaned, bearings re-greased and re-assembled. All went well and it is back in working condiditon. We will re-mount it tomorrow. Thanks to all the info provided, the job went very well. Thanks again, LJ

The Doctor
10-17-2005, 05:21 PM
You did remember to preload the gears as shown on my page, didn't you? Glad it all worked out.

Ed

ljchipmaker
10-18-2005, 01:50 PM
Yes, followed your instuctions to the letter. Thanks again

ljchipmaker
10-18-2005, 03:59 PM
By the way, How does the .001" dial come off of the 6-A?? I know the bezel just pops off, but we were unable to get the dial off. We noticed two small holes about 90 degrees apart and after a couple attempts decided we didn't need to take it off for what we were doing. Is there a internal spring clip, etc.??? Thanks again LJ