3D printing Widgets

I've now got the replacement Malyan M200 up & running & with a bit of help from Jon in Swansea I'm making progress on printing.
I've been working on the Nose parts, the one taking the most time is the spinner.
Being conical the first ones were straight sided & printed standing on the narrow end which came out OK.
When I changed to elliptical sides the surface finish was terrible. I concluded that the over-hang of the ellipse was causing the filament to hang over the edge.
So I turned it over & printed with the wide end on the table which cured the surface finish problem.
However the internal seat for the prop driver where the 12mm bottom recess switched to the 6mm hole had a very raggy surface because the printer was just crossing the gap with infill. It would have been no good trying to mount the prop driver onto it, it would just break away.
So the latest version uses a 6mm x 19mm penny washer in a counterbore in the top which will be glued in.
The other thing I've come across is the Z-axis Seam Syndrome cause by the printer stopping & starting at the same point in every layer. Changing this point to random in the settings has cured this so its all looking very promising.
I'll put some photos together & post them.

I was thinking when I was having trouble exporting files we should have a Freecad Topic, maybe we should also have a Cura one.

And another thing - I've been using masking tape on the table, just the cheapest stuff from Screwfix. Is the Scotchblue any better?
The parts seem to be overly sticking to the table when its finish & take some getting off. It seems to have got worse. Is the sticky building up on the table? What should I clean it with?
Will heating the bed help? I've been leaving the parts on the table for 5 or 10 minuts to allow them to harden.
On the subject of bed heating, is it needed all the way through the print? After a few millimetres of layer it cannot be contributing anything.


 

In my experience the parts release easier as the bed temperature drops, so higher bed temperature = better adhesion. I then leave it all to cool after the printing has finished before trying to release the part. I never switch off until the nozzle is below 60C.
Are you changing the tape after every print? To my knowledge Simon is still working with the tape that was on the bed of his Anet from new.

Last things first.
I only put new tape on if the old one is damaged. The last part came away cleanly so all I'll do now is to smooth out some wrinkles.
When I have had trouble releasing the part I have tried lifting it off with the tape. Usualy the tape just tears so the part must be stuck to the actual bed through the tape. Thats why I thought heat might help by softening whatever was holding it. It seems to me that the hot filament in the first layer must be forming an amalgum with the masking tape adhesive.
The bed on the Malyan has a ?non-stick? layer like a frying pan which is why I was wary of damaging it.

In my experience the parts stick to the tape best when it is new. With a heated bed and repeated printing the tape surface gets smoother eventually to the point where the first layer may no longer stick as it is laid down requiring the nozzle to bed gap to be reduced just a fraction.
For long tape life without damage the trick is to find the gap that is just enough. It is a problem if you replace just one tape strip as that will cause parts to stick much better than any older tape that has been left in place.
I always use a very sharp blade to help ease the part off as this reduces the chance of actual tape damage. With no self levelling bed careful observation of the first layer as it goes down can indicate which side of the print might be easier to prise off first.  
If the tape damage is small I simply move the print position to avoid it. My aim is to continue printing until the damage is such that all the tape need replacing as it is quite a tedious job to get the bed really clean and dry from the "baked on" glue to ensure the new tape sticks properly.
Yes a heated bed only directly effects the first few layers but it does create a warmer "atmosphere" around the whole print. As I have found the surface quality of a big print can be  effected if there is a cold draught from say a window blowing across the printer.
Hope this helps.  

I'm not having any problems sticking, the opposite in fact.
The tape is very thin (cheapest on Screwfix) & smooth, it feels smoother than some Scothblue I have.
It is a negligible cost & easy to replace the tape. The question is, "Is there a residual amalgum betwen the tape & the bed & what do I use to clean it? Isopropyl alcohol?
Could the black surface on the bed be to improve the sticking, not a non-stick surface?
Note the shadow of the part. When the tape is peeled off there is a faint shadow left on the black stuff.
Peeling the tape off you can feel the increase in stickiness as it reaches the shadow.
The wrinkles will more or less smooth out with the plastic scraper.
 
 

I recall from the days before printers had magnetic flexing beds that the 'blue painters tape' was the recommended product. Rather more expensive but lots of folk think it worth the price.

I echo the keep the bed heating on for the whole print.  Indeed, since my printer is out in a minimally conditioned space I have it in a tent that generally keeps the environment around the printer away from drafts and it generally ensures the temperature is more stable.

Glad to have helped MagPi get through some of the frustrations on the printing side of this hobby.

I use good old fashioned 50mm wide masking tape but it is on an aluminium bed. It was a recommendation from the supplier of the printer.
I also suspect masking tape is a good bit thicker than the tape you are using and the printed part certainly leaves no impression on it after removal.
As jon suggests finding what works best for your particular printer is all part of printer learning process.
 

I was getting abit of pick-up on the nozzle so I checked the table level, it seemed high so I lowered it by two quarter turns of the screws which improved it.

I decided it was time to move onto trying PETG.
I called up the Generic PETG profile on Cura & started to try to print NOSE 2E. The filament just wouldn't adhere to the old tape. I tried a higher nozzle temperature (the generic PETG profile had set it to 220) which gave some improvement so this morning I peeled the tape off & cleaned the black surface with a little (not Lidl) amount of Aldi Kitchen cleaner on a microfibre cloth & wiped it over with a wet cloth to remove any chemical residue.
I then set the temperature up to 240 & set it away on a 40mm square job I had done as a test piece.
There were a few whiskers as it got started on the first layer but it settled down & is now 80% completed & looking good.
I need to think about the settings for the first layer.

Up to now I had been loading the gcode programs into the printer by swapping the micro sd card which I didn't think was a good way to do it so I worked out how to print via the USB port in Cura, what we used to call DNC, Direct Numerical Control, drip feeding from a computer. Again no instructions & at least for me not intuitive but after a few trips to the internet I've got it cracked.

89% completed & looks good so I'll look at the initial layer settings & try the gyroid infill.

I had a little difficulty removing the print from the bed. It wouldn't knock off & was too low to push over so I had to use a Stanley knife to flip it off.
I haven't marked the table but will be going to Screwfix to get some Scotchblue.

I started it again to look at the initial settings & had a few false starts with it not adhering to the bed & stray strings.
I put the skirt back on as I read this gave the extrusion time to settle down before the job proper.
I've got the main print set at 240 which works fine but don't know what to set the inital temperature at.

Just remember Klippy's warning when using the direct cable link. If the PC "times out" the printer will stop!
This can become more serious with big prints that have to run for several hours.
I do use a micro SD card to transfer the G-code files to the printer so once it is done the PC can be safely switched off or left to time out.

I've got mine set so it doesn't sleep, I just send it to sleep or turn it off manually depending on how long I'll not be using it. The bigger risk is damaging the USB socket, they're not meant for continual use.
I'm going back to trying Scotchblue tape.

I have my room quite cool, the window is always open except if its too windy or too cold so the filament may be hardening as soon as its left the nozzle when it first starts up. I'll try closing the window or making a cover.

We got an email from Malyan EU after-sales support. I was going to ask about the table but when I looked it was a "no-reply". It had a Whatsapp number but when Val looked it up it was in China.

If Trump manages to upset the Chinese we'll have to go back to living in caves.
 

You are getting there in nice short steps...  PETG, if it has good adhesion, often has is in abundance.

My settings for PETG use the same 1st layer temperature at 240C.  For the 'bed' my settings are 80C. Seems hot but it likes it.

I have a magnetic bed plate so I let it cool for a few minutes and then remove the plate from the machine and after the whole thing cools down it usually comes off with a bit of flex. 

I printed off a NOSE 2E in PETG yesterday, it was quite successful but the surface finish still needs looking at.
So then I loaded up the Stable Vice, I don't know why they call it that, it has connotations - horses! It fitted on my bed at 100% so I printed the smallest piece which turned out OK.
This morning I decided to have a go at the biggy, the Schraubstock, 9hrs 42mins as I've got the time to supervise it. I'm using the micro SD card in case I need to do anything on my PC which will upset it.

When I started the pre-heat the Scotchblue curled uplike toenails, I'd previously always trimmed it back to the edge of the plate so instead I stuck the surplus back to the plate sides which seems to have worked.
When I started it off the initial lay didn't adhere very well, it tended to be the near left corner so I eased the adjuster up quarter of a turn. This improved it & it got under way though I think it still needs a little more judging by a taper on the wall lines.
Its now well under way & looking good.

The test square I did for levelling was only 40mm square, I need maybe a square frame shape almost the size of the table.
makerworld.com/en/models/1727770-stable-...ts#profileId-1834758
 
 

Looks OK but unless there is some "structure" inside it (or is it just support) I would not have printed it lying on its side.
With an open top it would have been better placed vertically on the bed unless of course that would be taller than the printer's vertical limit.
Just an observation. 

I had to abandon the Shraubstock, The Scotchblue lifted at the ends & the part started to lift & got too messy. I tried to restart it directly onto the bed but the first depositions didn't adhere.

I set about making a 115 x 115 frame with a 100 x 100 cut out to set up the first layer. I had a load of trouble with the adjusting screws, I couldn't get the gap to repeat but I got a passable first layer in the end. I don't know if its more difficult to set the levels with a larger square than a small one.

I printed the first part for the stable vice lying down because thats how it landed on the Cura plate.
Looking at it now the layers are visible on the top & there is a bow in them and thats where the stress is so it may well pull apart.

I'm reprinting it standing up with a brim. At first it was directly on the plate but the brim didn't adhere, it actually came loose, so I put the Scotchblue back on. That's behaving itself this time so we'll see what it turns out like.