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Is a DNC-only machine livable

Is this based on some bad experiences???? I’ve drip fed my Mori with Mitsu control whenever programs get too big for over 10 years now and never had data loss. Some programs as large as 4 meg though most in the .5 to 1.5 meg range. I do use hardware handshaking though as I feel it more trustworthy than XON/XOFF.
Back in 2000-'01, I was working for a Mastercam reseller, and would handle DNC setups for clients. Occasionally there was one where no matter what we tried, the connection wasn't perfectly reliable. Could have been something to do with the grounding situation, or the specific old machines. I have, twice in my career, seen a machine take off wildly, breaking the tool and scrapping the part, due to a character lost while loading. Not a huge risk, but it is multiplied if you have to transfer the file for every part, rather than once.
 
Wow that's crazy.

Worked around and on several machines over last 20 years and never seen an issue with DNC.

Not my first choice to send programs but sometimes its just the way it has to be.
 
Wow that's crazy.

Worked around and on several machines over last 20 years and never seen an issue with DNC.

Not my first choice to send programs but sometimes its just the way it has to be.
Yep, me too except I started transferring programs by RS232 in the early 80s. So much better than using tapes like we had to before that.

In those early years the programs were hand written so always able to fit in memory. Wasn’t until the mid 80s until I had to do a few jobs by drip feed. As CAM has increased in power, programs have gotten bloated and the need to drip has increased to where the bulk of any new work I do, ends up being drip fed.
 
Yep, me too except I started transferring programs by RS232 in the early 80s. So much better than using tapes like we had to before that.

In those early years the programs were hand written so always able to fit in memory. Wasn’t until the mid 80s until I had to do a few jobs by drip feed. As CAM has increased in power, programs have gotten bloated and the need to drip has increased to where the bulk of any new work I do, ends up being drip fed.
I'm running 10 megabyte programs. A lot of that could be compacted with subs if it mattered, but with 64GB of program memory and loading files from thumb drives, it just isn't an issue.
 
Yep, me too except I started transferring programs by RS232 in the early 80s. So much better than using tapes like we had to before that.

You had a head start on me lol.
Was Mid 90s for me. Couple of the machinenes had tape readers but everything was rs232 when I started in the trade.

I can still picture the screens on the PC with the progress bar showing the % remaining to run
 
We run our machines DNC only even though we don't have to. There are advantages and with the right software (Cimco DNC with Moxa ethernet to Serial adapters) and control systems it is nice, the Moxa units which are directly next to the control allow for reliable data transfer at whatever the max Baud the port will take. With Millplus controls there is no problem with lagging or anything because it has three files being worked with at any given time with DNC. One is being filled, one is being read, and one is being deleted. This sequence continues and there is no lagging even when feedmilling with "Opti" toolpaths which are code-heavy. You can be updating the same program you are actually running on your PC so the next time it is sent the changes take effect. Yes, if you have a power outage or network issue that will stall the code and the machine will pause. Using a laptop or a UPS easily helps with this. Usually power being lost affects the CNC anyway. The machine "pausing" is the absolute worst case, it cannot receive "Bad code" or anything, either it gets the code or it doesn't and stops at that line. I think the greatest benefit of DNC is having unlimited length programs and the ability to start a huge program immediately without having to wait for it to transfer, or load up in the control. There are downsides too, I did like the Fanuc Data Server setup that I had working via FTP on our Hitachi Seiki... that was instant drag and drop with main programs calling up subs of each major set of operations so if you wanted to make changes while it was running to files you could as long as it wasn't the sub that was running. This is handy when you are working on parts that take 6-8 hours of constant machining which is pretty common for us. You can imagine how large some of these programs get!

On a much older Kitamura with a Fanuc (6MB) control I tried something similar to the Millplus dripfeeding with Dan Fritz's software PC-DNC https://www.pc-dnc.com/aboutus that would communicate directly with the controls tape reader port on the motherboard. It too worked very well and this was with a control that had no look ahead whatsoever. I think to run that software you need to have an older PC operating system (XP?) but for people looking at getting the most out of an older control like a Fanuc 6 it is tough to beat that software setup.

Just my take on this subject,

Dave @ Nerv
 
...Occasionally there was one where no matter what we tried, the connection wasn't perfectly reliable. Could have been something to do with the grounding situation, or the specific old machines. I have, twice in my career, seen a machine take off wildly, breaking the tool and scrapping the part, due to a character lost while loading.

I mentioned this in my earlier comments, but the Moxa "Nport" Serial-to-Ethernet devices solve these problems, at least they have for us. They even make wifi units though I prefer to keep ours wired. What is nice about the Cimco DNCmax software is that they have settings in that software that allows for optimal communication directly with the Moxa units so data transfer is as fast as possible with no issues with bad code. It sure does make setting up each machine easier.
 
Fanuc memory addon from Kitamura was reasonably priced. Paid Kitamura, the fanuc tech showed up and installed it, and when I say reasonable I don't mean PC prices but not crazy. Wish I could remember the number maybe $1200 installed.
 
I mentioned this in my earlier comments, but the Moxa "Nport" Serial-to-Ethernet devices solve these problems, at least they have for us. They even make wifi units though I prefer to keep ours wired. What is nice about the Cimco DNCmax software is that they have settings in that software that allows for optimal communication directly with the Moxa units so data transfer is as fast as possible with no issues with bad code. It sure does make setting up each machine easier.
Moxa have been the best USB to RS232 converters I used. No point in using anything else now IMO. Also DNC4U software is superb. Reasonably priced and feature rich. Has great DNC functionality too. Even a provision for mid program restarts in a DNC operation.
 
Hi All,

I'm looking at a Makino KE-55 for my home shop, but the memory is absolutely tiny. Small enough that DNCing is my only option. What are the drawbacks to DNCing all my programs? If I have a laptop next to the machine with a serial port and fusion 360 installed, it seems like it's fairly low friction -- I just post and DNC right from the laptop. What might I be missing for what makes this annoying and potentially a dealbreaker?

Best wishes,
Evan
Home shop - are you on power co 3 phase, or home converter? One of the big potential causes of RS-232 issues is earth ground noise. Home converter, especially an RPC, could contribute significantly to that, especially since the laptop isn't going to be running on the 3phase. It may make a difference if you run the laptop on batteries vs charger. Ideally run the RS-232 with parity if both ends support that to reduce the chance of error.
 








 
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