I’ve been happily printing for a while now with my Wanhao Duplicator i3 using PLA but a recent problem has occurred wherein, during the initial stages of a print with a large base surface area, the first layer has not stuck to the raft.
This produces a surface effect similar to the gills of a fish, where, in one direction, the surface bows and parts of the filament stick up proud of the raft about 3mm high, forming raised ridges open on one side, at regular intervals. This obviously greatly interferes with the rest of the print.
I’ve been using MatterControl as a slicer since I started using the printer and haven’t had any problems before. Most of my prints, including these failed ones, have been done with an extruder temp of 200’C and a bed temp of 70’C.
The failed prints were mostly regular hexagons with a 100mm side to side length (for a set of coasters), and a final depth of around 7mm although this is irrelevant as I’ve stopped the prints after the first layer has been done and can see no hope of the rest of the print going well.
Note how the raft has printed perfectly, but as soon as the actual print starts, it messes up…
In the image provided I let the print go for a bit so the faint outline of the letters ‘TN’ in the Borg font (recommend it, really good font!) can be seen - to demonstrate what happens when another layer attempts to print on top of the first distorted one, it’s not a defect.
If anyone could point me in the right direction or knows how to sort this problem out it would be greatly appreciated!
1 Like
Wultz
2
1st: Do you really need the raft? Try without it.
2nd: Lower the speed of the first layer at about 10-15 mm/sec
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It’s probably worth getting a glass bed to print on rather than the surface that comes with the wanhao. A little bit of glue stick or hairspray and you’ll get good bed adhesion without the need for a raft at all. I suspect your issue is just with general warping made worse by the size of the piece you’re printing. You could also try swapping to a skirt rather than a raft to hold those edges down, but a glass bed is king in my opinion.
I have the same printer and what ive found out is:
1. The bed was really warped and that made problems like this
2. On the Wanhao I always manually lowers the speed for the first layer to 50% and then go back to 100% after first layer(s) are perfectly done
1 Like
Wultz
5
I think that the Wanhao surface is great.
The trick is to rub and clean it with isopropyl alcohol before EACH print.
Tens of prints with buildplate temp 50C, not a single miss (when you use alcohol).
Fair point, I had some warping in mine so swapped to glass to keep things flat and haven’t looked back.
a_raush
7
Hi Zac, for PLA raft is not needed, hotbed neither actually.
just apply painter tape to bed surface (or place a piece of glass on it with a tape on it)
Be careful to use a very good tape not a cheap one (scotch blue tape is very good). PLA will adhere perfectly
Same here. Glass plate solved my slight warp problem too. Can’t imagine ever going back. Being able to take the glass off before removing a print makes it easier and also seemed to reduce how often I had to level the bed, since I don’t apply pressure to it when scraping off a print.
Yes I suppose I could try without a raft, although I’ve had problems before where, with large surface areas like this one, the print sticks too much to the bed and damages the surface. I’ll try to lower the speed too, cheers.
I’ll definitely try without a raft, it appears that adhesion is significantly reduced when printing onto a raft compared with the bed. Also, that seems to be the general consensus here, that a glass bed greatly improves prints - definitely on my to do-list!
Wultz mentioned lowering the speed too, I’ll give it a go, thanks!
I’ve got some white spirit lying around, will that do? But like I mentioned initially it’s not a problem with the print adhering to the bed, rather the print adhering to the raft. Although temperature of bed could be an issue, is 70 deg.C too high?
Looks like a glass bed will be a reasonable future investment, many of you seem to think it’s the problem here. I’ll try all the suggested fixes that don’t mention a hardware change first.
I know in simplify3d there is a setting for the gap between the raft and the print. I would try to decrease this distance. If it worked before:
1) Have you changed suppliers of PLA
2) Have you changed colors of PLA
On a Makergear M2 (a similar printer) I have been running temperatures a lot warmer. I use makergeeks PLA and have been running that at temperatures up to 230 degrees C.
Looking at your print it looks like it is not bonding. I would increase the temperature. I would also not print on a raft for this part. I would print this part on blue painters tape to get it to stick to the platform and lower the speed for the first layer.
Monitor your temperature while printing and make sure you are not getting temperature fluctuations. I have had a thermistor start to fail that reported my printer was running warmer than it actually was.
I always cover the build plate with frog tape (painters tape) and then add some glue (prit stick) this always got me a perfect first layer which let it stick well. Just experiment with the amount of glue. Good luck!
sascha
UPDATE:
- Printed with no raft,
- Fan speed at 100% constantly,
- Lowered speed of first layer by around 50%,
- Added hairspray to bed
Result: the first layer stuck a lot better when printed directly onto the bed but still produced a bumpy effect
The image below shows the bottom of the coaster,the first layer to print…
I’ll use Simplify3D and see if that makes a difference.
I haven’t changed colours/suppliers at all, been happily printing in black and white 1.75mm PrimaValue since I got the printer, although white always gave a better result somehow…
I’ll mess around with the temps too, see if that changes things, thanks.
4202Js
19
try tip at 185 bed at 65 for pla
I agree. This definitely looks like a warped print bed. My gigabot has a badly warped bed. It’s hard to find a spot level and flat enough to get a good first layer.
