DRO suggestions for mill

Discussion on all milling machines vertical & horizontal, including but not limited to Bridgeports, Hardinge, South Bend, Clausing, Van Norman, including imports.

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john_j
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Location: Minneapolis, MN

Post by john_j »

I just ordered the Easson ES-10.

I compared that model with the Accu-Rite VUE. I spoke with two people at Accu-Rite (one in customer service and one service technitian) and was surprised at how poorly they knew their product. Neither could tell me how to enter the tool radius when using the arc milling funtion and the user manual didn't cover that. I asked how to zero an axis and they had to figure that out too (they didn't know right away). I couldn't find that in the manual either. They also warned me not to expose the system to temperatures below -20F even in storage. While I won't use my mill at minus 20F, it certainly will be exposed to that temperature when I turn the heat off in my shop in the winter time. I was really surprised at this coming from a supposed high end source like Accu-Rite.

The rep I spoke with at Easson knew his products inside and out and even knew quite a bit about the Accu-Rite stuff too. He patiently answered all my questions without any sales pressure.

Here's why I finally chose the Easson ES-10 over the Accur Rite VUE

*0.0002" display resolution versus 0.0005" for the VUE.
*Simple, one-button settings rather than menus and sub-menus on the VUE
*No warning about possible screen problems from low temperature storage
*$500 less cost
*Built in calculator with trig functions
*More detailed user manual
*More tolerant and knowledgeable telephone assistance
Converting good metal into scrap since 2005.
Jose Rivera
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Location: Vallejo California

DROs

Post by Jose Rivera »

One of the things that has keep me away from considering DROs is the bulkiness, the wring, the pain installing it and calibrating.

There is an instrument called a laser interferometer that I used to see the metrology people use to calibrate our CMMs at Rockwell Int’l. back during the Space Shuttle program.

These work with a laser, a digital read-out and a mirror.
I wonder why now day with the low cost of lasers and electronics, DROs are not done this way, where all you need is a small laser, the read-out and a small mirror attached to the moving axis.

Maybe I am missing something here.
MichaelC
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Joined: Tue Mar 22, 2005 7:07 pm

Re: DROs

Post by MichaelC »

Jose Rivera wrote:One of the things that has keep me away from considering DROs is the bulkiness, the wring, the pain installing it and calibrating.
Jose, I use to feel this way till I heard people rave about their Newall DROs and how easy they are to install. Back in 2005 I bit the bullet and bought one when I bought a new mill. Every other DRO manufacturer ought to buy a Newall just to copy their mounting hardware. Very easy to set up even on rough castings that aren't flat. I was able to mount my scales square to table, full range, within their specification very easily.

michael
Jose Rivera
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DROs

Post by Jose Rivera »

My beef is not with the display unit but with the bulky scales no matter how easy they will be to install.

For starters all the ones I know require you to drill and tap the machine, something I refuse to even consider.

Second those scales are way to bulky and will make it harder to cleaning of the machine, not to mention delicate.

I have used Lathes and mills with these installed. No questions, they're a dream to use, but I have not scrapped material enough to feel that these will be a money saver for me, though they will speed up things.

Also they tend to cause you to lose the skill of machining without them.

My comment on using a different way of doing the reading of movement was hoping for someone that may know about a different way.
I have called a company that used to manufacture these laser interferometers and their answer was that they no longer make that product, but I found this company, they look expensive !!
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BadDog
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Post by BadDog »

I'm an ignorant newbie in every sense of the word, but I don't see the problem. What little I (think I) know I've picked up from reading more than experience; but it gets me by most of the time...

Like you, I am very resistant to drilling/tapping my machines, so I tend to make extension brackets and what not to utilize existing features if I can. But I did finally have to give in to mount some way covers on the Bridgeport.

Anyway, it came with Accurite scales and a off-beat display already mounted. I never used it without them, but really don't notice them being in any way a problem for cleanup or use. Yeah, chips will collect on them, but they collect all over, so it really doesn't hit my radar as a problem. Likewise the y-axis travel looses, what, an inch or a bit more? But again, I've not seen a problem for my needs.

And for 9 out of 10 mill "jobs", I use the hand wheels and never turn on the DRO. But once in a while, it is SO nice to be able to quickly hit a measurement, or repeatedly hit a zero, or whatever. Reduced worries about "slop" (if you lock the travel anyway), no worries about counting revolutions, no need for an extra stop/scale/DI to verify/locate the zero, just easier in general. And for someone that's doing this for fun and "relaxation", that's a very good thing.
Russ
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big art
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Post by big art »

I have seen lasers used on horizontal machining centers to check accuracy and changing parameters to correct wear and machining errors. They needed to maintain a clear line of sight between the laser and the mirror so you would still need a tube, tunnel, or channel to prevent the laser beam from being broken by anything such as chips, air hose, brush, rag,etc. When I first entered the trade I used only dials for positioning the table. I later learned to use optics, travel dials, and dro's and now that I own my mill I purchased a dro for it, not to cut down on scrap but because it reduces the time for positioning the table. In over 30 years I have never lost the skill to use the machine with dials only. As for as a dro being to delicate, if you already take proper care of your machine your readout will not diminish the use of your machine, you can still do all the machining operations you could befor adding the dro. The scales do take a little space and in situations where you need the full "y" travel I have used mills with the scale mounted on the front of the table with no adverse condition. If you are looking for an alternative to a dro check to see if travel dials are still available. they have their faults, driven by a rubber wheel they can slip on a dirty or oily surface but still farely reliable. I can't give the specifics on accuracy. They make digital scales like on digital calipers that can be mounted to x,y,or z to aid in quicker positioning. But no matter what you choose you have to give up something. As far as a laser readers goes I would expect it will not revolutionize the industry with unheard of low prices. Even then you would still have to mount it to your machine, double stick tape, I don't think so.
john_j
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Location: Minneapolis, MN

Post by john_j »

As I wrote earlier, I just ordered the Easson ES-10 DRO from DRO PROS. The next day, I realized that I made an error in one of the axis travel length measurements, so one of the glass scales I ordered will be too short.

Feeling rather foolish, I called DRO Pros and explained what I did, fully expecting that I would have to pay for my mistake. This was 100% my fault and I rightfully should have to pay for return shipping and any price difference for the longer scale that I need. I couldn't believe it when they told me not to worry about it and that they would ship me the right scale at no additinal charge and no charge for shipping. In return, they asked only that I return the short scale when I have time to do so. I'm simply in awe of the awesome customer service they just gave me. Almost nobody gives that kind of service any more. It's incredible. If they are that helpful when I screw up, I'm sure that any future service or warranty issues will be no problem at all. These guys are incredible.

In camparison, earlier today with another vendor, I goofed around on the phone for 45 minutes dealing with a mistake that the vendor made, trying to get $12.00 credited back to my visa card. I went from one person to the other, 3 different phone numbers and had to threaten to contact the BBB and the State Attorney General to file fraud charges. All this to fix a simple mistake over a $12.00 item.

Later on I get on the phone with DRO Pros over a mistake that was my fault, that is costing them probably $100, and they say "no problem", "we want you to have the right system", and they eat the cost. Their service is incredible.
Converting good metal into scrap since 2005.
Bill Shields

Manually Cutting Arcs

Post by Bill Shields »

Yes, you can, and I have cut arcs using the method described, BEFORE DROs were generally available. How do you think a CNC machine makes an arc using X and Y? Same thing...breaks it up into 1000's of little linear moves and has at it....

It is a very tedious process.....which is why you can get offset radius heads (or used to be able to)...offsets the tool by R radius, then you crank the tool around the work...like a jig grinder head.

Never done it WITH a DRO, and probably never will since CNC came to the world...and my town and my farm / basement shop. Too many things to do.

I like Amercan made stuff and supporting whatever manufacturing I can in this part of the world. Another topic...

Have a STAR (Canadian) on Jim's lathe - works just fine, but uses racks - gears / encoders rather than glass scales....a trade-off on price / size vs. potential loss of accuracy over time....but still more convenient than a dial - esp with bad eyesight being a factor.

My Wells-Index mill has an Accu-rite on it that is 25 years old and works just fine. Yes, it is obsolete and I cannot get parts for it, and yes I have had to make a couple of bits to repair damage done by previous owner(s).

It is plain jane...just coordinates, nothing fancy...don't really need more with a CNC sitting right next door....

Were it me and my choice, over a bunch of fancy features, I would look for a 3 axis system that covers BOTH the knee and quill through a summing box.

This way, you can set ZERO at the top of the part / tool touch and no matter what you move - knee or quill, the DRO knows where the tool is.

But that is just me being lazy....

As for being afraid to drill holes in machines...as I look around, I don't have one machine that I HAVEN'T drilled holes in..if not for a light or a coolant hose, switches, DROs and collet racks / wrench holders. You name it, God created flat surfacs to have holes drilled into them (with the exception of the top of the tables)....
john_j
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Joined: Mon Apr 16, 2007 2:54 pm
Location: Minneapolis, MN

Post by john_j »

I finally purchased and installed a DRO on my JET JVM-836 mill.

I bought the Easson ES10-3M5 from DRO Pros http://www.dropros.com/
This is a 3-axis unit with glass scales and a lot of nice features at a very reasonable price compared to other units.


The unit came with lots of nice mounting hardware, but I wanted a more custom fit, so I ended up fabricating my own mounting brackets. It took me quite a while to get everything mounted and properly aligned (due to my inexperience), but I'm finished now and it really came out nice.

I tested the precision of each axis of the DRO by mounting a dial indicator on the quill to measure a point on the milling vise on the table. I then zeroed the axis on the DRO and zeroed the dial indicator. I then cranked the axis back and fourth several times over its entire length of travel, then went back to "0" on the DRO and noted the dial indicator reading. The largest value I ever measured on the dial was 0.0002". Of course, this doesn't check for linearity errors, but it's all I can do with what I have. I thought it was quite good nevertheless.

I also have to say that the support from DRO Pros was outstanding. I haven't been treated that well by any company for a long time.

Photos are enclosed.
Attachments
DRO screen.JPG
DRO Display bracket.JPG
DRO Z axis.JPG
DRO Y axis.JPG
DRO X axis.JPG
DRO full view.jpg
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millman5
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Post by millman5 »

John J

If you haven't already purchased. Take a look at these : http://www.shars.com/product_categories ... ut&&page=6

I purchased one of this same brand from someone on ebay for even less & was able to pick scale lengths. I took a chance (1) because they were cheap, (2) could get a 36" & a 24" scale rather than the standard mill or lathe package (3) was to be installed on a VTL that arrived here about the same time that the pilgrims landed at Plymouth. I was afraid the machine had to much wear on the gibs, & might destroy the scales.

It has been going for well over a year now without an issue.

The hardware package that came with mine was really pretty good. Very nice swing arm for the readout itself (wee bit short for my taste). the cables are very flexable & well shielded with flexable metal jacket conduit. good ssecure attatchments for cables.

As with most cheaper items there was just enough in the mounting instructions to guide you through safe reader to scale tolerances but not much else. Operating manual not completely useless but close.

Came with a 2 year manufacturers warranty for all that's worth. It shipped from Hong Kong. There is supposed to be repair depots here in the US somewhere, but I didn't research it.

EDIT: I should have read the entire thread before posting. I see that you are done. Oh well maybe someone can make use of the info for a similar project.

Very nice looking install. I have made 3 very custom installations on machines that were manufactured before DROs were invented. Hard to do but all work very well.
If it works Don't fix it....
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seal killer
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Post by seal killer »

John-J--

I am going through the same decision-making process, but have pretty much already settled on DRO-Pro. I have some off-topic questions for you, though.

What is that covering your mill table?

Do you use the sine table built into your rotary table very much? If so, for what kind of tasks? What model is it? Grizzly? Enco?

You really did do due diligence on this project and I intend to take advantage of it.

Thanks!

--Bill
You are what you write.
Jose Rivera
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Location: Vallejo California

DRO

Post by Jose Rivera »

I think that learning to use a milling machine using a DRO from the beginning will be similar as doing math with a calculator and never learn to do it long hand.

Take away a DRO and the person that has never learned to dominate milling without one will be lost and frustrated.

Is best to learn long hand first and then use a DRO to refine the skill.
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