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I have a 2023 DNM5700. Is the coolant/chip management really supposed to be this terrible?

Former Doosan/DN employee here.
@LockNut on here, is a current employee, as well.
The aluminum fines you're creating are (obviously) the cause, so upgrading to a better conveyor will get rid of the majority of issues. I dealt with quite a few customers who swapped out the standard conveyor for a Mayfran or Hennig. Money well spent. The LNS is a general purpose conveyor.
There are M codes and Keeper Relays for the conveyor and augers, so that they run whenever the machine is cycling.
This is just a misapplication of the conveyor. Agreed the sales person should have and maybe did suggest a better conveyor to fit this application. I can't tell you how many times I heard "I can't afford that" or "you're just trying to upsell me" or "I'll be just fine" until your not just fine. I hear about these kinds of issues maybe once or twice a year out of the dozens if not hundreds of DNM's we sell every year.
Talk to your dealer. I know for sure they will be able to do something for you under these curcumstances.
Vern is displeased.
Vern wants the Churu you owe him for knowing this all along. You couldn't understand when he said "filtration of fines" (meow...mrroow...echt..echt) so he had to sit in that basket and you still didn't believe him.

Oh, and get him a stool so he can reach the cycle start button.
When you turn on the chip conveyor after emptying your rubbermaid bin does it sound like gravel hitting the bottom of the bin?

No? Increase your feedrates. Get that spindle load up there. Fanuc runs at 100%. It's not exaggerated, you can actually use 100% all you want.

Make chips, not dust.
When you turn on the chip conveyor after emptying your rubbermaid bin does it sound like gravel hitting the bottom of the bin?

No? Increase your feedrates. Get that spindle load up there. Fanuc runs at 100%. It's not exaggerated, you can actually use 100% all you want.

Make chips, not dust.

Easy to say for roughing, but when you're doing a lot of 3d surfacing in alu. it's pretty much impossible not to make filter clogging glitter...
I have a New DN SVM-4100 sitting right next to a vf2. the LNS basic conveyor sucks for fines and small chips. My tank/conveyor discharge is slightly different but still causes the same problems. the air knife kit for the conveyor helps a bunch to not bring stuck chips back into the machine but it can really run your compressor hard depending on chips and coolant stickiness. some but the screen still gets plugged up. I make a family of parts that use a ton of small endmills so small chips are a problem. I agree the microfine conveyor would be great but its a steep price to pay.
I don't have a fancy machine, Just an 0ld 2003 Fadal 4020, but I have fought clogged up chip baskets going into the coolant tank for many years, machining aluminum and brass with tiny endmills (1/32"). Tip I found on here was to use the paint strainer bags for 5 gallon buckets. I bought 30 on amazon in a pack, put over my coolant discharge channels and haven't dealt with a coolant overflow in the past year. I am on the original two bags still, even filling with chips they keep working. Best $20 i have ever spent.

Not sure if you could somehow implement something like that into your system.
I'm still struggling over here. I changed to a non-roughing endmill to help make bigger chips, but it still is giving me a lot of problems. The small screen between the main sump and the coolant sump gets so clogged up so quickly that I have to clean it constantly, I briefly tried just taking it out but then when I do that, the coolant pump intake screen becomes clogged with big chips. Here's a picture of the first chip catcher basket after less than one hour of run time, with the chip conveyor running at full speed the whole time. It's so bad that I cannot walk away from the machine for more than 15 minutes or else the coolant pump screen gets so starved that the coolant shuts off.

I have a timer in my shop that I set for 15 minutes and every time it goes off I'll walk over and dunk my hand in the coolant tank and manually clean the pump screen. Then I'll pull the screen between the two tanks and clean that. On my haas I used to run lights out, but now I can't even run over a lunch break. Talked to someone at the machine tool supplier and they recommended some $30k system but I just can't afford that. On the verge of just going back to the haas because at least I could let it do it's thing. I'm a one man shop but I am thinking about paying someone just to clean the screens for me.

To make matters worse, since my last post, now that I am making bigger chips, they tend to build up on the edge of the conveyor more, which, if it builds up long enough, will divert the coolant straight onto the floor. This is with the conveyor running at full speed. Twice I have walked out to the shop and had 90 gallons of coolant gone straight down the floor drain.

It's all just very frustrating and not what I'd expect from a $120k machine.

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I've never run a vertical with a 'standard' hinge conveyor that actually worked when running all aluminum. Neither does a scarper conveyor work, we bought a GF Mikron show room 5 axis with a scraper type conveyor, and that is also problematic especially with larger chips. But we knew what we were getting into, and some care with tool selection and educating the operators get us by more or less. IMO For high production aluminum prototyping or production, the only real soultions that worked for us is a fancy Drum& backwash setup like the Mayfran Consep 2000(even this requires maintainance every half year), or a brother that flushes everything into the chip bin and putting filter paper there and having the operators shovel chips every other hour. Something like the Mayfran Consep 2000 will absolutely solve your problems, but the hefty price tag is hard to justify.

If one of those conveyors are out of the question, then honestly the only fix is to select your tooling carefully based on experimentation and expereince, finding self made or 3rd party 'hacky' solutions and still mucking around with it all the time. Fines are going to be a major issue, so are roughing chips that are overly large, sometime reducing the amount of coolant has a positive impact. Putting the filter paper used in a paper band filter in the collection pan may help and make the work easier(not sure if applicable here).


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Yes, at this point you need to bite the bullet and replace that with a drum filter conveyor.

Maybe the sales guy screwed you over, or maybe you fucked up and didn't properly set out your requirements. Either way the reality is that you need a drum filter conveyor. A bitter pill to swallow maybe, but you'll be extremely relieved when you have it installed.

I don't think they necessarily cost $30k as ManualEd suggests, I'm fairly sure the last one I bought was something like £12k, but it was a good while ago...

It was one of these: https://cromar.co.uk/products/swarf-conveyors/series-ii/
If nothing else there is a good PDF on that page that you can look at and see how they work.

Be very careful when ordering that everyone involved fully understands what you're doing on that machine, including volume of removed material per hour, particle size, and maximum coolant output of the machine.

You might also consider a cyclone filter to keep ultra-fine sludge from building up in your main tank.
You need a filtered conveyor. I have the LNS MH250 on my DNM5700 and I have no issues. Cleaning out that chip tray all the time is ridiculous. I cannot believe the unfiltered conveyor is even an option.