Inexpensive DRO

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Mr Ron
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Inexpensive DRO

Post by Mr Ron »

Does anyone have an opinion about this DRO kit? The company is veteran owned and operated and claims to have assembled the best components from all around the globe in their kits. They are a lot cheaper than Newall, Fagor or Acurite. I am interested in the EL400 kit for $780. http://www.dropros.com/Electronica_Mill ... _Mill_Kits:
Mr.Ron from South Mississippi
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Steggy
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Re: Inexpensive DRO

Post by Steggy »

Mr Ron wrote:Does anyone have an opinion about this DRO kit? The company is veteran owned and operated and claims to have assembled the best components from all around the globe in their kits. They are a lot cheaper than Newall, Fagor or Acurite. I am interested in the EL400 kit for $780. http://www.dropros.com/Electronica_Mill ... _Mill_Kits:
I read a couple of pages on their site and got the feeling it is a foreign company. The English is inconsistent with what the typical American or Canadian website would have. Also, I noted that in the list of tools needed to do an installation, all taps were metric, not English. That too suggests foreign-made product.

None of the above is meant as a criticism of their product. There isn't any way to judge quality until the DRO is in use.
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Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
earlgo
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Re: Inexpensive DRO

Post by earlgo »

Mr. Ron, I know nothing about these DRO kits.
Having said that, I bought an electronic 1 axis scale from a well known Chinese importer and found that when the axis was moved, it took the display a bit of time to catch up. In fact one could stop cranking and the display would still be changing. Final positioning is accurate though.
All I am suggesting is that you ask what the lag time is before you decide to spend your money.
--earlgo
Before you do anything, you must do something else first. - Washington's principle.
John Evans
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Re: Inexpensive DRO

Post by John Evans »

Have had a "DROPRO's" DRO on my BP since 2010 with no issues. Haven't needed to talk to them in several years but the last time I did they were still native American English speakers ! The DRO is imported parts but you have a issue no need to return to CHINA !! Actually I think all the big name brands are mostly imported parts. If money were no object and I was going to buy a new DRO it would be a Newall as their mounting hardware is the best and easiest to use I have seen.
www.chaski.com
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Steggy
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Re: Inexpensive DRO

Post by Steggy »

earlgo wrote:Having said that, I bought an electronic 1 axis scale from a well known Chinese importer and found that when the axis was moved, it took the display a bit of time to catch up. In fact one could stop cranking and the display would still be changing.
The lag problem of which you speak is common with low-cost DROs, and not just Chinese ones. It has to do with the performance of the DRO's microcontroller, which is what takes the X-, Y- and Z-axis inputs, computes position and generates the display. The cheaper DROs use 8- and 16-bit microcontrollers, which have to execute more instructions to compute position than a 32-bit microcontroller. Also, the 8- and 16-bit microcontrollers are often clocked at relatively low frequencies, which has a direct effect on real-time performance. All of that combines produces the display lag. Accuracy is usually not compromised, but it would be wise to verify that before making the first cut after installing the new DRO on your machine.

As always, you only get what you pay for.
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Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
John Hasler
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Re: Inexpensive DRO

Post by John Hasler »

BigDumbDinosaur wrote:
earlgo wrote:Having said that, I bought an electronic 1 axis scale from a well known Chinese importer and found that when the axis was moved, it took the display a bit of time to catch up. In fact one could stop cranking and the display would still be changing.
The lag problem of which you speak is common with low-cost DROs, and not just Chinese ones. It has to do with the performance of the DRO's microcontroller, which is what takes the X-, Y- and Z-axis inputs, computes position and generates the display. The cheaper DROs use 8- and 16-bit microcontrollers, which have to execute more instructions to compute position than a 32-bit microcontroller. Also, the 8- and 16-bit microcontrollers are often clocked at relatively low frequencies, which has a direct effect on real-time performance. All of that combines produces the display lag. Accuracy is usually not compromised, but it would be wise to verify that before making the first cut after installing the new DRO on your machine.
This is why (in addition to cost) I want to buy *just the scale*. I can buy a 16 bit ATmega micro that can easily keep up for $5.00. I suspect that the reason the processors are underclocked and therefor slow to respond is to extend battery life.
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Steggy
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Re: Inexpensive DRO

Post by Steggy »

John Hasler wrote:This is why (in addition to cost) I want to buy *just the scale*. I can buy a 16 bit ATmega micro that can easily keep up for $5.00.
...and a 32 bit ARM for not much more. :D
I suspect that the reason the processors are underclocked and therefor slow to respond is to extend battery life.
Yep! CMOS power consumption is directly related to operating frequency, since current draw is highest as a CMOS gate changes state. Fully static microprocessor and microcontroller designs can actually tolerate having the clock completely stopped, which reduces current consumption to microamperes. It's a feature commonly found in implantable defibrillators, especially those powered by the Western Design Center's 65C02 core.
———————————————————————————————————————————————————————
Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
earlgo
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Re: Inexpensive DRO

Post by earlgo »

Oh. Some Help Always Required.
--earlgo
Before you do anything, you must do something else first. - Washington's principle.
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NP317
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Re: Inexpensive DRO

Post by NP317 »

I purchased a DRO Pros 4-axis mill set with the EL700 Color LCD Display. It installed easily on my mill, and works without lag or problem.
It totally meets my needs and the Display has more calculation capabilities than I am likely to use.

The 4-axis setup provides readings on both the Quill and the Table positions, and can be summed to give you the correct tool-to-part distance regardless of which one you move! This has been a useful capability for performing deep boring/drilling jobs, such as the tender hand pump for my locomotive.

I will provide more info as requested, including pictures of the installation of the 4 axes.
~RN
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MillComplete small.jpg
Mill DRO MountBracket2 small.jpg
Mr Ron
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Re: Inexpensive DRO

Post by Mr Ron »

NP317 wrote:I purchased a DRO Pros 4-axis mill set with the EL700 Color LCD Display. It installed easily on my mill, and works without lag or problem.
It totally meets my needs and the Display has more calculation capabilities than I am likely to use.

The 4-axis setup provides readings on both the Quill and the Table positions, and can be summed to give you the correct tool-to-part distance regardless of which one you move! This has been a useful capability for performing deep boring/drilling jobs, such as the tender hand pump for my locomotive.

I will provide more info as requested, including pictures of the installation of the 4 axes.
~RN
Do you have magnetic or glass scales? It looks like a school setting you are at.
Mr.Ron from South Mississippi
Bill C
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Re: Inexpensive DRO

Post by Bill C »

I have had two very positive dealings with the folks at DroPros. They are based in California and provide excellent customer service. The first experience was buying a glass scale from them to replace one I broke on the Z Axis of my Bridgeport. It was a big scale, mounted to the side of the machine and the knee. The original scale I broke was part of a kit I got on sale from Grizzly. The scale broke due to my mistake (in use) and Grizzly wanted almost as much for a replacement scale as I paid for the whole kit. DroPros came to my rescue with a perfect replacement for about 1/3rd the cost.

Then when I bought my 12 X 36 lathe, DroPros had their magnetic scale DRO system for a good price. Not cheap, but a good value and I liked how I could cut the scales to length. The DRO on the lathe has been a pleasure to use, never a hint of a problem. The folks at the company are great to deal with, even called me back to confirm a few things when I bought that replacement scale. Call them if you want to be sure before you order. They also have some excellent how-to videos on you tube.

No connection to the company, just a happy client.

Bill
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NP317
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Re: Inexpensive DRO

Post by NP317 »

Mr. Ron:
I used the magnetic scales on the mill DRO package. VERY easy to use, including cutting to length if necessary.
The 4 scales that arrived with the kit were all the correct length.

I installed a Grizzley 2-axis DRO on my 14-40 lathe. It required careful installation to prevent twist damage to the glass scales. The glass scales were also bulky and required compromises during installation. Had I understood the small size of the magnetic scales, I would have used them instead.

And my machines are in my own new (2-year old) shop, not a school, although a University setting is a part of my work history.
That nice clean looking corner behind my mill now is more cluttered. Typical aging shop...

And the white board visible on the wall still has arabic and cyrillic writing all over it, as my two sons were learning both languages as teenagers, just for the experience. It has been cleaned since that picture was taken. It is my note board for making quick drawings and noting dimensions. It is visible while using both the mill and lathe. Very convenient!

~RN
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