Sizing for a DRO (slides)?

[ScrapMetal]

Now that I have a mill, and I'm close to getting power to it, I need to look at find a replacement for the DRO system that is currently on it. The box itself is DOA and without a circuit diagram it would take me a loooong time to get it back working if even possible. I don't know the condition of the slides, of course, as the box is dead. Even if they are "good" I don't know if they would be compatible with a new box.

With that being said, I am looking to maybe get a whole new DRO setup. I believe these to be the specs on my mill (I'll measure it before I order anything.):




So, 10" x 48" table but longitudinal travel is 34" on a 46" table???

Cross is 14" and vertical knee is 16.5".

Now, if I am looking for a 3-axis system how is that sized out? Do my slides need to be 34"+? for ends/mounting or what?

Basically, how do I figure the right sizes to order?

Thanks much,

-Ron

[f350ca]

Ron
You size your scales for the movement required. A 34 inch scale will be 4 or 5 inches physically longer. Best to check out some of the sites selling them or the manufacturer of the one your interested in to get exact sizes for clearance and mounting purposes. Adding an inch or to to the scales costs little if anything, if you have the room go slightly longer to be sure not to crash at the ends. The first one is a little scary to mount but not hard, after the initial one it becomes pretty simple. Some manufacturers have slim scales for tight spots like the compound on a lathe if space is limited, You could cut a block of wood the size of the scale and see if it fits and clears though all the table movements.

[EdK]

Here's a video done by DRO Pros showing how to measure the travel and select the correct scale.

http://www.youtube.com/watch?feature=pla...AxDsxiufMo

Hope this helps.

Ed

[ScrapMetal]

Thanks guys. That will help a lot.

Now I just need to decide on which system to go with. (Yes, I've read the threads here about them, still haven't decided. )

-Ron

[Mayhem]

Hey Ron, you do know that whatever one you decide to go with, we will expect a full write up of the install with pics!

[stevec]

(06-19-2012, 02:36 PM)ScrapMetal Wrote: I need to look at find a replacement for the DRO system that is currently on it. The box itself is DOA and without a circuit diagram it would take me a loooong time to get it back working if even possible.
-Ron

Ron, being the cheapo that I am I'm wondering why you don't explore the possibilities of repairing (or getting repaired) the existing DRO?
-Steve

[ScrapMetal]

(06-20-2012, 04:58 AM)Mayhem Wrote: Hey Ron, you do know that whatever one you decide to go with, we will expect a full write up of the install with pics!

Of course...

(06-20-2012, 01:28 PM)stevec Wrote:

(06-19-2012, 02:36 PM)ScrapMetal Wrote: I need to look at find a replacement for the DRO system that is currently on it. The box itself is DOA and without a circuit diagram it would take me a loooong time to get it back working if even possible.
-Ron

Ron, being the cheapo that I am I'm wondering why you don't explore the possibilities of repairing (or getting repaired) the existing DRO?
-Steve

Good question. It's an old Sargon 2-axis DRO. I've tested the power supply in the box and it appears to be okay. When I have it under power and apply pressure to the inner boards I get some random results on the display but no actual "function". That leaves me with a number of possibilities, one or more bad solder joints, cracked circuit board(s), faulty chip(s), and or faulty discrete components. There are probably a number of other things I can't think of at the moment.

Now, if it is bad solder joints and/or discrete components I could track it down myself but that would take more man-hours than I want to put into it (rather be reducing some useful metal into swarf). If there is a crack in one of the boards (and they are multi-level) there is no good way to repair it without spending an enormous amount of money (impractical). If faulty chips some can be replaced but others are proprietary and most likely couldn't be found/replaced.

To avoid putting a lot of personal hours in to it I could send it to an electronics repair shop (as worthless as they seem any more) and spend a few hundred dollars for them to tell me they can't fix it or that they can but it will cost more than the unit is worth.

Now, even if by some miracle the box could be brought back to life, I have no idea if the slides are any good. They look a little rough in spots and the cabling is shredded in a couple of areas. If they were also bad I'd have trouble finding replacements to go with the box as I doubt "modern" units would have "parallel port" type connectors or be compatible with the old electronics. (This I don't know for a fact, just conjecture.)

The bottom line is that I'm afraid I would end up spending way more time and money than it would be worth and still maybe not have a decent, working system.

Always open to suggestions though,

-Ron

[stevec]

Ron, sounds like you've thought it through A-Z. I accept your decision to go shopping.(good of me, right?)
Sorry I can't help you there but I'll be watching your updates, my Mitutoyo on my Tree mill is acting up.