This topic contains 31 replies, has 9 voices, and was last updated by jhr 3 months ago.
-
Posts
-
Chris if this is the case then why are Cel not replacing returned units with these new parts? Also surely they should change the Cel branded PLA filament to a formulae that works on their own printers??? Although i respect your explanation it has me rather confused because clearly there is a simple fix.. Yet it seems that if the fix is known it’s not being implemented.
2 machines i have sent back within the last 2 month. The first machine i am seeing this problem to the point i cannot print. The second machine (the last one returned) i am pleased to say is still going and i am not seeing any filament slip. That brings me to another thought… unless Cel has replaced the parts on the newest returned machine and not the previous, then why am i seeing the problem when i am using the exact same Cel branded (same colour) filament on both machines?
www.lee.rcha-uk.com
www.rcha-uk.com
www.rcheliaddict.co.uk@made2fade I think that the parts mentioned in Chris’s post are not yet available or they would be replaced on all the printers. In addition, the parts are integral to the print head and can’t just be swapped out, so the print head has to be replaced. Based on what I have heard, the S2 print head is currently in testing. This means that it still has to pass testing and then get any final modifications complete. Then the factory will have to spool up production from making a small number of test articles to making a large number of production articles. Then you have to do a production test run to make sure that the change to production parts hasn’t revealed any quality issues. Iterate changes if required, and then finally start production. This means it may be several months or more before these changes are complete.
I have to second Chris’s suggestion to change from PLA to XT or nGen. I don’t see any reason not to. The only time I use PLA is stress testing printers or if a customer needs it for some specific reason. Otherwise I use XT mostly and some nGen. I have run probably 22 kilos of material through my printers and haven’t looked back.
The other point to look at is how you store your PLA. I am located in a desert and still have to keep PLA in an airtight container with a humidity reducer or it will start to skip. The moisture added to the air by the air conditioner is enough to make the filament wet over time.
I operate two Betas and one Production Robox.
See my 3D Hub site at https://www.3dhubs.com/phoenix/hubs/ben@made2fade I agree with @bhudson. My experience with PLA was not the best. Some reels of filament print well others give random slippage, I found that brittle PLA will not print and always gives slippage, flexible PLA prints well but has to be dry. My test is to see if filament breaks when you bend it. Since I changed to XT I have not had a problem and only failed prints I now have are my errors. I had 3 head seal failures during the time I used PLA but nothing after I changed to XT (could be a pressure issue. I am not sure, also CEL have been working on improving the head reliability), there was always the problem of degradation with PLA that spoiled longish runs over 10hrs, black bits being extruded through nozzle and it could affect the nozzle output requiring frequent purges to restore full flow, I do not get this with XT.
hope this helps
John
@john & @bhudson, as much as i agree with you guys it does not explain why i have one printer currently not missing a beat yet another one constantly slipping and im using the exact same filament.
I will try the XT however our usual suppliers do not sell it. Which is a problem for us as we have accounts with them.
Is any of Cels branded filament any good? Whats their ABS like? We have plenty of it but found that it was not sticking so well in early days of printing. Thats really why we changed to PLA.
www.lee.rcha-uk.com
www.rcha-uk.com
www.rcheliaddict.co.uk@made2fade There are several possible answers to the behavior.
- Extruders are not consistent. They are tested only to meet a minimum requirement and often exceed that requirement. If you have an extruder in one printer that exceeds the requirement by 30% and an extruder in another printer that exceeds it by 5%, you will see more slip errors in the second printer. The extruder passes all requirements and tests, but the tests are run with known good, clean PLA. If your PLA is wet, or is getting wet, and is increasing diameter as it soaks up more water, the second extruder will still pass all the tests but will be unable to continue to feed the filament when the filament swells beyond a certain point. The first extruder will still power through until its load limit is reached.
- Print heads are not consistent. This is due to manufacturing tolerance requirements. As with all the extruders, the print heads are tested to meet a minimum requirement and not limited to a maximum requirement. So if you have a print head with a filament path slightly smaller than another print head, and you try to feed large or wet filament through the print head with the smaller path, the filament will take more force. Combine an extruder that is close to the minimum requirement and a head that is a little small with some filament that is slightly oversize or wet and you get a printer that will skip, but will pass all factory testing.
These are both outside of the control of anyone involved in the manufacture of the printers. Every printer is tested before it ships out. The plastic shipping clips that come with your printer are used to test the performance of the printer. You will note they are printed on draft mode with red PLA. This is a worst-case scenario for the printer and if it passes that print test, it is acceptable to ship. What it doesn’t take into account is environmental considerations at the customer location. This has been taken into account to the extent possible by the design team, but no product can be produced exactly the same every time. The more repeatable the product is, the higher the cost. So you are looking at a printer at a price that is affordable but there has to be a little more variance in components to keep the manufacturing and scrap rate acceptable and keep the price down. CEL has done an admirable job both in the design and quality of the product and in their support. If your problem printer has not been back for a tuneup, I suggest you send it in.
I use CEL PLA all the time testing printers and when customers request it. I also have to keep it in an airtight container with very low humidity - about 2-5 percent is my estimate. I am in a desert and still have to recharge those air driers every 6 months or so. This is not limited to CEL PLA either. I keep all PLA, including ColorFabb PLA/PHA, the same way because if you leave any PLA out in the atmosphere it will absorb water and swell. Most printer manufacturers compensate by using a larger diameter Bowden tube, which eliminates their ability to feed flexible filament to the print head using a Bowden tube design. The tradeoff is that they can feed filament to the hot end (print head) that is wet, dirty, etc. with less issue. They also end up clogging their hot ends much more frequently in my experience.
If you have a slip issue with nGen or XT, you are looking at either an extruder issue or a head communication issue, most likely the latter. If you are seeing a slip issue coupled with an inability to eject the material, any material, without using the “Eject stuck filament” command, you are looking at a faulty print head. I have one of these right now. Every time I eject material I have to do it manually because the extruder, tested to 25% above required load, can’t pull the filament out due to a defect in the print head. This defect developed over time and once the head fails or reaches the point that I can’t stand the manual eject sequence, I will replace the print head.
ABS will stick well to the PEI sheet once it has been sanded. I have printed long, narrow parts with ABS that printed just fine, though they wouldn’t stick until I sanded the bed. I don’t print with ABS because I can’t stand the smell and because it is soft. I prefer a harder, more flexible filament that doesn’t just bend when loaded since I do live springs integrated into parts with ColorFabb XT. I also like that PET is non-toxic.
You do not need a SmartReel to run ColorFabb XT or nGen. The profiles are approved and included with the software. Buy the reel from ColorFabb and sit it on a turntable next to the printer. I have run probably 22 kilograms of filament using this setup and it works perfectly. You need a little more room next to the printer but you can also use a vertically oriented spool holder to account for that, or print a dumb spool, or reprogram an empty SmartReel and reload it with the ColorFabb PET material.
I operate two Betas and one Production Robox.
See my 3D Hub site at https://www.3dhubs.com/phoenix/hubs/ben@made2fade I had adhesion issue with ABS, that was before sanding of PEI surface was recommended, I have not gone back to try it. I found XT to be much better for my project with respect to shrinkage and print quality, which is making a patterns for casting, I. Its not perfect as we have to coat with mould release paint to iron out the ripple from the layers, I am not in this as a commercial venture yet. The casting house we are using say these prints from Robox are the best they have seen from 3D printing.
I have 2 machines with a spare head & extruder. When I was having slippage issues with PLA I tried all combinations of machine, head, extruder & filament. All combinations gave me the same result that the filament was the issue.
The extruder is well designed in that it drives both sides of the filament, but not suitable for flexible filament. Many others only do one side, at least this was true when I was surveying the market before I settled on Robox.
I have printed in excess of 1500hrs with one of the machines, the other is more of a standby/backup (which I got relatively cheap).
I don’t know if CEL have different upgrades to your machines only they will know, but all mine are early 2015-late 2014.
John
@john If you are interested in flexible filament, the new V2 extruders are fitted to run flexible filament. I have used them with Ninja Flex to some success, though I am still working on solving a few issues. CEL has had better luck with the material. V1 extruders can be refitted to run flex also.
I operate two Betas and one Production Robox.
See my 3D Hub site at https://www.3dhubs.com/phoenix/hubs/ben@bhudson Thanks very much for your response, it is an option, however at this time I do not need flexible filament. When the dual material kits eventually arrive (2 on order) I get extruders that will handle flexible filament, hopefully before I need to use flex filament.
You must be logged in to reply to this topic.
