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perplex

Retraction between same part? with Cura

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Hey All

im having trouble getting parts of my print to be hole. i have a feeling when its moving from 1 part to another its not retracting, so when it goes to print, nothing comes out for abit because its oozed/stringed

ive tried turning on retraction prime, and still no luck. i notice its more of a issue when moving longer distances but as you can see from the picture, it has issues with just 15mm away

is there a setting i can fix this with? it just wont draw the circles. ive attached pictures of the issue im having

215.jpg

the line going to the circle is the entrance line, not the exit

n8e2b.jpg

the left side is just the image above and the right side the line is the exit line this time

hope someone can help

Cheers

Edited by Guest

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You have a few problems including the one you mentioned. All of them are fixed if you move the nozzle closer to the tape. You need to squish that filament into the tape more.

Also - unrelated - but the filament will stick better if you wash that blue tape briefly with a paper tissue soaked with rubbing alcohol (aka isopropyl alcohol) to wash off the waxy surface that i assume keeps the tape from sticking to itself when it is rolled up.

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You have a few problems including the one you mentioned.  All of them are fixed if you move the nozzle closer to the tape.  You need to squish that filament into the tape more.

Also - unrelated - but the filament will stick better if you wash that blue tape briefly with a paper tissue soaked with rubbing alcohol (aka isopropyl alcohol) to wash off the waxy surface that i assume keeps the tape from sticking to itself when it is rolled up.

 

Thanks for the reply, i did what you said and no success, but i was amazed how much more it stuck when cleaning with the alcohol, as in harder to remove

ill give you abit more information.

i set my nozzle to a paper where it grips the paper abit, normally i print the first layer at .2mm but the first post picture was at .4 or .3 to see if it was any different

here is a picture of the first layer at .2, i have tried .15 first layer but fine the filament doesnt come out very well, as you can see it fixed the first hole but the left hole is completely broken, ill attach a video of how it is moving so you get an idea of what im saying, i also have a feeling if i could get rid of the oozing from when it moves it may fix, but there is no setting for this, that i know of

58uox.jpg

i find when it moves long distances it fails to start the print, i have tried another slicer and it worked fine, weather or not it was because it never did as long of a move, i dont know, but i like cura and wondering what setting may fix it

 

here is a video of the first circle if you were wondering, it looks abit thin, like the oozing is taking what it needs

 

Edited by Guest

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I looked at the new photo. I watched the two videos. Your nozzle is still too far from the tape. Do you have a leveling procedure? If so your procedure needs tweaking. Do you have bed leveling screws? If so turn them all a bit to move the bed closer to the nozzle.

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By the way if you don't believe me you can probably just push up on the bed a little and see the improvement while it's printing.

 

hmm, ill level it again, im using a piece of paper for thickness

when i changed the first layer hight to .15mm nothing came out, so i thought it was too close, but ill try get it closer

no i dont have auto leveling yet, only screws

on average what is a good retraction number? i was using .8 but someone said thats way to low

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ok so i just checked the bed and i cant get it any closer, i can only just fit a piece of paper in it, and its scraping the paper.

is there a setting to retract everytime it moves away from a line?

Edit - i just tried to post again and it didnt post so maybe it didnt like me posting 3 times in a row, so ill edit it here for now

after days and hours of testing, i finally found the fix what i was after

Settings>Travel>Tick "Combing Mode">Change it from 'All' to 'Off'

this way it doesnt stay inside the part and retracts, so this way it does ooze over my print, so when it goes to print, its full of filament, and not half empty because its over my print

i just need to fine tune my retraction and prime, any idea what is a good starting number for these?

have you messed around with z hop? is this something i should add since its got a good chance of hitting parts?

Edited by Guest

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Well when you get large parts you will have trouble with them sticking to the bed because you aren't squishing the bottom layer very well. In other words this problem is going to come back to you. Even though they say to use paper I recommend you then get even closer by another .1mm as if there was no paper in the leveling process.

Retraction for bowden machines like the ultimakers is typically around 4 to 5mm. For printers where the feeder is mounted right on the head it's much smaller - typically 1mm but every printer is different.

z-hop is great for delta printers but for "box" printers it tends to give you worse quality. There is a "first layer combing" feature somewhere so that you can do combing on every layer except the first layer - but not sure if you can do it the other way around, (all layers but first layer), lol.

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I believe gr5 is right: the first layer should *not* look like round sausages that are dropped onto the bed. But it should look like a very thin plate that is really squeezed *into* the bed. Very different.

If not squeezed into the bed enough, the molten filament will stick to the nozzle, instead of to the bed. And that is what I see in your videos.

Especially for tiny details, such as holes, short lines or dots, this is very important in my experience: that is the first place where bonding will fail.

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