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maico
08-06-2005, 09:06 AM
Does anyone know who carries the traveldials or someone have one for sale?

The Doctor
08-06-2005, 09:25 AM
http://www.southwesternindustries.com/swi/prod_measurement.shtml

Michael Az
08-06-2005, 09:51 AM
I got one on ebay some months back that was new in the box for $325. I can't imagine doing without it now. I like it better than dro.
Michael

rockrat
08-06-2005, 10:57 AM
Michael - What is it about the traveldial that you like over a DRO?

MikeHenry
08-06-2005, 10:59 AM
They're pretty pricey new from SWI ($600-800?) but some patience on Ebay can yield a nice used one for $150 or so. Make sure it has the base and the tensioning jig is nice to get for those models that need them. The jig is $35 or so from SWI but I managed to cobble up a barely usable one from sheet metal and scrap for at least that much in effort <g>.

You'll also need a couple of spherical washer sets, which can be had from McMaster-Carr if they don't come with the one you get.

Mike

MikeHenry
08-06-2005, 11:02 AM
Rockrat,

I like the TAD on a lathe when turning or threading to a shoulder with power feed as it's easier for my eye to track the analog dial arm than digital display. I can usually disengage the feed within a couple of thou with the TAD. On a DRO I can be as much as 20-50 thou off. Other folks don't seem to have that problem, though, so YMMV.

Mike

rockrat
08-06-2005, 11:15 AM
MikeHenry - I see said the blind man (as he put the car in drive). I was just curious.

We have TVD's on the lathes at work. They are ok. Setting zero is a bit more than I care for. But that is a minor gripe. If you don't keep them clean, they skip around. That has bit me on the tail more than once. If something bumps it, I worry that it is off.

The cnc system that they have (prototrak) which runs from TVD's is nice but God help you if it skips or gets bumped. The control thinks that the table stalled and it will take off at a high rate and bust eveyrthing in its way, including the TVD pickup.

As for buying them, eBay would be my first choice as well. I can't see paying almost $800 new and only read one axis.

rock-

The Doctor
08-06-2005, 01:31 PM
BTW, I have just recently completed cleaning and repairing my first Trav-A-Dial, which I hope to get mounted to my lathe sometime soon. I took lots of pictures of the reassembly process, and will probably be putting up a web page detailing the cleaning and reassembly process sometimes in the next few weeks. I also have copies of the few small pieces of literature about mounting and calibrating the Trav-A-Dial's people have sent me. So, if you buy a used one and it won't turn completely, or if you find a mounting specifications are a little hard for you to figure out yourself, just drop me an e-mail and I will send you what I do have.

I would also give a warning to all of you who own Trav-A-Dial's. Actually several warnings.
First warning -- keep the wipers in good condition, it only takes a few tiny specks of metal to screw these things up nicely.
Second warning -- if you notice that your Trav-A-Dial skips or seemed to hang up at any point, don't try to finish the job you're on before you fix the problem. Immediately remove the Trav-A-Dial from your lathe, and tried to move the wheel through at least 6 inches of travel with your finger. If it binds up at any spot, put it in a drawer and don't use it again until you take it apart and clean it, as I will soon be able to instruct you on. The first Trav-A-Dial I had a part would only move about 4 inches in either direction, then it would lock up completely. Upon disassembly, I was surprised at what a tiny amount of metal actually made its way inside and caused it to quit functioning. There were only a couple tiny chips in there, yet one of the gears was missing half the tooth. As it is fairly lightly loaded, I don't think that will cause of much trouble, but there was a worse problem a few teeth over. One of the gears appears to be made out of diecast zinc, and it had a piece of yellowish metal actually embedded into the gear tooth. It was embedded so tightly that I could not pull it out with a pick, I ask it had to dig at the tooth with the blade of a utility knife. This may have changed part of the tooth profile enough to affect its accuracy in that area by a few thousandths of an inch. I will not know that for sure until I get to compare it to a dial gauge about every five thousands of travel over 6 inches, a testing process I am really looking forward to:-( So let that be a warning, if you try pushing your Trav-A-Dial once you got pieces of metal in it causing it to bind even a little, you may end up doing serious damage to it. Remember, they do not sell parts to these things. And I really doubt there are any home shops that are capable of making parts to a high enough accuracy to make one of these things work right ever again. So, if you damage even the smallest part beyond use, your Trav-A-Dial becomes a parts machine. Then you have to look on eBay once again and end up paying anywhere from $50 to sometimes over $200 for another workable Trav-A-Dial:-( Don't let this happen to you!

Ed

Jim Caudill
08-06-2005, 01:40 PM
Hey Doc!, Remember me? I'm the one that sent you a unit last fall(?). The one that would only go short distance in either direction before jamming?

Michael Moore
08-06-2005, 02:19 PM
As Michael points out for some things an analog display is much better than digital.

If you've got a panel of analog gauges you can set them so all the needles point straight up when in the normal position, and a quick glance will show anything that is out, where with the same number of digital gauges you'd have to actually read and process the numbers. And if the gauge is actually in motion a digital display can be pretty useless.

I'd like to see someone who makes DROs include at least one axis of a linear display, whether LED bar graph or just a row of small LEDs. If you could set a zero point and then have it delete elements of the display as you come down to zero you'd have your nice analog display. Maybe include the option of several different resolutions? .100, .050, .010 or .001?

It doesn't seem like that would be too hard to implement if someone knew their electronic stuff (which I don't).

cheers,
Michael

[This message has been edited by Michael Moore (edited 08-07-2005).]

Davis In SC
08-06-2005, 09:34 PM
One of my DROs has a flashing display feature, to flash, as you approach zero.. But it is too much trouble to set, every time...

neonman
08-06-2005, 09:53 PM
The Doctor:

When you do yout web site on Trav A Dials,
please post it.

I also have one I want to clean up. It doesn't stick. but feels gritty.

neonman

rockrat
08-07-2005, 08:53 AM
The Doctor.... Doctor Who?
Sorry could not resist.

Doctor, your project sounds fantastic. Can't wait to see the photos. I know that SWI makes a real stink about opening up the TVD. They don't want your to do it. Most likely due to the pocket watch type insides I would think.

I do have a TVD and would like to clean it before I install it. Can't wait to see your posting.
rock-

Michael Az
08-07-2005, 09:24 AM
rockrat, Mike and Michael have gave the answers to why I like the trav a dial better than dro. It is very easy to read when using power feed. With dro the numbers zinging by are just about unreadable.
Ed, I think it would be great if you did make a web page about the work you have done with these. I use wool felt for the wheel cover and have had no problems with mine getting chips inside yet. I think it is important to be sure the felt is the right thickness to keep the chips out.
Michael

Your Old Dog
08-07-2005, 10:00 AM
http://www.raysstuff.com/shop/hsm/herewego%20copy.gif

Just when I thought it safe to put the wallet away! Looks like a nice tool to own if it could be had for the right price. As of this moment eBay spit back 4 when "Trav-A-Dial" was searched.........

The Doctor
08-07-2005, 08:33 PM
Jim, yes, I certainly remember you. The one I received from you is the one I took apart, cleaned out, and reassembled as I have spoken about above. I was just in the process of finishing up that job, which would have been followed by talking to you in seeing what price we would work out, when my friend was diagnosed with leukemia. You may recall seeing that post a month or so ago. Well, I spent a lot of time doing research on that. About that time, one of the hard drives in my house's network server went down, which caused me a bit more trouble. Then I had to send my main computer, a ThinkPad T30, back to IBM for warranty repairs. During this time, the Trav-A-Dial was stuck in a drawer and forgotten. In fact, I probably wouldn't have remembered it for a while longer had it not been for this thread. A bit of a shame actually, I needed to make a couple of bushings for the brake bolts on my wheelchair a few weeks ago, and a Trav-A-Dial would've been very useful. I will be dropping you an e-mail in the next day or two to discuss this Trav-A-Dial.

MikeHenry, I believe that one of the pieces of literature I have on these Trav-A-Dial's was supplied by you. It is now cleaned up, OCR'd, and turned into a very compact PDF file. It will be on the web page.

neonman, no problem. When I get the page done, or at least done to the point or it may be helpful to someone, I will be posting it here as well as on practical machinist and Chaski. I find it truly amazing, despite the usefulness of the Trav-A-Dial's, I can find almost no information whatsoever on these things anywhere on the Internet. This is what led me to consider making my own page. BTW, I fired up Dreamweaver a little while ago after I read this post, if I don't get distracted I will probably have something up by the end of the week. Very rough and ugly I'm sure, but useful.

rockrat, Doctor Who is actually where I got the name. I always thought that that was an awesome series, and I'm absolutely thrilled to see that it's back in production. I thank eMule for being able to get episodes here in the US, as I have not seen them anywhere on TV just yet. I will tell you this about working on Trav-A-Dial's, it ain't brain surgery! The model I have already serviced was the original model, I believe it is called a GD-46? I'm sure the other models which do not have a collection will dial are pretty much the same internally. This one did not have the epoxy potted screws, so I didn't have to dig the proxy to get apart. There is really nothing complicated or high tech inside of these things, but there are few things to watch out for. One of those things is that there are shims everywhere! You must be very careful you don't drop a bearing peace out and lose its shim, or you will be looking at a complete disaster. The other thing that needs to be known is how to preload the backlash eliminator when you put it back together. It's simple to do, you just twist one gear on the input wheel until a whole alliance, drop in a 1/16" drill bit, and assemble from there. I have a picture which illustrates that pretty well. You should also remember that the Barings in it have probably not worn too much, and will not need adjusting. Don't even dig the epoxy off the adjustment screws, you're just asking for trouble monkeying with those if everything is fine. The one I worked on did not have the screw set with the proxy, they were locked with paint. I left the housing sitting for a very long time and mineral spirits, and it ate this paint away http://bbs.homeshopmachinist.net//frown.gif Getting the bearings adjusted to where I felt they were correct once again was absolutely no fun, I think it took me longer than the rest of the job put together. Don't go there.

You'll all be hearing from me again soon.
Ed

andypullen
08-09-2005, 07:55 AM
I have a reader head that needs some work, but no mounts. Maico, are you interested? Contact me off board....

[This message has been edited by andypullen (edited 08-09-2005).]

The Doctor
08-20-2005, 03:41 AM
Okay, I always seem to do these things a little behind my promised time. Anyway, I've got most of my first clean/repair your Trav-A-Dial article posted. The unit shown is the oldest model,a GD-46. I suspect the newer unit with a single needle will be pretty much the same internally, I think the model with the two coaxial needles will be close enough that you will be able to figure it out from what I have posted, unfortunately I do not have one of the coaxial models to work on. As for the switchable inch/metric model, I would expect that when is a bit more complicated inside, I also do not have one of those to work on.

If you things to note before you visit the page, I could not locate a few of the pictures I had taken when I put the page together, so I have to go back and retake them. These pictures should be done a few days and the text to go with them should be added at that time. I do not currently show how to remove the knob, so I will describe that here. The knob is a two-piece affair, it has a centerpiece which is firmly attached to the shaft, and an outer piece which rotates on that to allow you to set to zero. To remove it, hold the measuring wheel steady with your thumb and turn the knob on the shaft until you can see the set screw through the hole. I think you can figure out how to remove it at this point, I will warn you that there may be shims on the end of the shaft which you need to remove and store with the knob. Also, I can't really illustrate how to remove the dial bezel, but what I did was work a fine jewelers screwdriver in at the edge of it and try it out. The indicator needle pulls off very easily with thumb and forefinger, do not force it. The printed portion of the dial can be loosened gently with a bent pick and removed, be careful not to apply any pressure to the needle shaft when doing this. The shaft is hardened and will probably break before it bends, and you can't buy parts. The last two screws to separate the cases are under the peace you just removed, they are quite obvious once you get it out.

On the newer models, the six crews all come in from the bottom side of the gauge, and they are plotted with epoxy. I have one of these I will be rebuilding next, I will post photos and my best advice on removing the proxy when I'm done, for now you have to work up your own digging strategy. The three of epoxy filled holes down the center or the bearing adjustments, do not dig the epoxy out of these!

The information I have given above will be added to my web page, probably within the next couple of days. I expect to have pictures of the second Trav-A-Dial's service a long with that tutorial up in a couple of weeks, plus I have a brochure to describing the device's installation and calibration. As I add these things, I will add to this thread letting everybody know I have updated the web page. I will also be posting about this page over at Practical Machinist and probably also on Chaski.

For now, here is the address to my tutorial Trav-A-Dial Tutorial (http://home.comcast.net/~marconi30/Trav-A-Dial/GD-46/GD-46_Repair.htm)

Jim Caudill, I e-mailed you about a week ago and have not yet got a reply. If you did not receive my mail, please e-mail me at marconi30@comcast.net and let me know your new e-mail address.

Ed