Perimeter and layers not bonding

Post Reply
robsta
Posts: 2
Joined: Sun Dec 30, 2018 4:18 am

Perimeter and layers not bonding

Post by robsta » Sun Dec 30, 2018 5:37 am

Hi everyone,

I'm new here and to 3d printing, so I apologise if the answer to my issue is an obvious one.

So I got the printer (i3 Pro W) for Christmas, built it boxing day and got it up and running the day after once I'd ironed out a few creases, as it were.

I printed a couple of test pieces without issue, and today started printing a "proper" item, all using the filament included with the printer. About 2 hours into a 3 hour print, the included filament ran out so I switched to a new spool- again a Geeetech filament but this time black. This is where I started to run into issues. The switchover went fine, and it transitioned from the last of the original blue filament to the new black filament without missing a beat. However a little while after that the print started to go really blobby. This only affected a particular section of the model, and was fine once it had moved beyond this area, and fine when it went back over the area again later.

I later went to print a new model, and this is my real issue. After a shaky start where it wouldn't put down certain areas of the base layer (the perimeter and 80% of the base were fine, but a couple of areas just didn't take, but more like a feed issue than an adhesion issue), it continued fine until the print was complete. However upon removing the model I found that none of the perimeter layers have adhered, vertically or horizontally. Also, overall rigidity seems poor compared to the previous print, although they are very similar items. Individual layer adhesion seems fine, but I suspect the layers haven't bonded to each other which is why it feels flimsy.

My first thoughts were perhaps I need to increase the extruder temperature- that the filament is going down too cool and not melting the adjacent layer- yet both filaments were the same brand, and from a bit of googling 190 degrees seems a suitable temperature for PLA. I found many people with similar issues on other forums, with a variety of possible solutions (none of which were increasing the temperature), yet it seems to me the issue must be something to do with the filament, as that's the only thing that has been changed from the previous print (i.e. no other setting altered), and it was only when I started using this filament that the problems started.

So anyway, I thought I'd ask on here, before I tackle another print and risk the same happening again.

robsta
Posts: 2
Joined: Sun Dec 30, 2018 4:18 am

Re: Perimeter and layers not bonding

Post by robsta » Mon Dec 31, 2018 8:34 am

Problem solved. I raised the extruder temperature to 200 which solved the layer adhesion completely and improved the perimeter adhesion. I watched as the first layer was going down and could see slightly gaps between the walls. Checked the filament diameter and it turns out my 1.75mm filament is actually 1.65mm, checked at ten points (it was pretty consistent though to be fair)- cheers Geeetech. Anyway changed the diameter in the settings and that's that sorted.

Post Reply