The twisted rook

[Mjolinor]

I printed it again at 230 and the print has signs of burning. I can print with dayglo green and it comes out better than both blue or transparent, blue is better than transparent and doesn't really seem to mind what temperature you use.

Whatever I do the castellations on the top look like rabbit poop. Perhaps they are too small for ABS, is that likely?

At the moment I am trying to set up Skeinforge, making small changes to the settings and reading about each one, not that there is a lot of info available. I have improved bridging immensely by slowing the head down over the bridge, this seems contrary to the info available on the net where most people say you should speed up over bridges.

On the one posted above I wiped the head every three layers and it seems not to be a good idea, the model has cooled too much during the wipe. That is what is causing the apparent layer separation that was mentioned. This is why I need to find a way to "leave Z" during the wipe sequence but I am going to have to do that in the source somewhere that I can't find yet.

First born stole the last rook before I could take pictures so I will try to find it and take pics.

[Dargonfly]

Couldn't agree more, although I am yet to mess with S3D properly, looking at your prints, it is pretty clear you went to extraordinary lengths to calibrate your machine, and it paid off - you could print in most software and it would give you a comparable result, alot of that comes down the model really, and of course the work put in to make sure everything is A1. You actually probably have some of the best print quality I've seen come out of a flashforge, well beyond what I just sufficed with (I got it to a point where it was good, not as good as yours but it was good enough to get the projects flowing) if Flashforge had half a brain they would ask you for some advice but as I've said a few times now, FF have very little interest in user input, it's the one area they have always failed in. Sadly we have probably helped more of their customers here than they have.

The only thing I can still notice in your prints are the vertical ridges, I get those too.. not sure quite how to fix that one. Like in your big rook, on the bricks, they have some lines running vertically down them.. I get that too on roundish objects, even if the mesh is smooth.. but on my kossel, it doesn't.

Thanks for the nice words

Yeah the vertical ridges on cilinder shapes are a riddle to me too... I have a last few ideas that I will test over the coming week, but if that doesn't solve it then it's just the limit of the machine's design.. but then again, the Ultimaker can do it and the only real difference there is that it uses a bowden system.. can imagine that perhaps the vibrations of the extruders do something. As soon as I've figured it out I'll let you all know!

[curious aardvark]

Actually a lot of the improvement IS because of the way s3d slices.

I printed some plugs for a black and decker workmate this week. Has a quite a overhangig slope on it.
With makerware the edges kept curling and the final underside was horrible - even after I'd sanded it on my disc sander.
The very same modekl printed with same settings and filament on s3d. Was completely different. It does this reinforced edge infill thing that prevents the ovehang from curling and the finished print was smoother than the sanded ones.

I'll do the rook with s3d, and I'm certain it wil be a lot better.

That said dargonfly has really put the work in on his printers. I just keep copying what he's done :-)

[Dargonfly]

..It does this reinforced edge infill thing that prevents the ovehang from curling and the finished print was smoother than the sanded ones.

True, this is something that S3D does - I'm not completely sure, but I believe that it's doing that because it recognizes that part as 'bottom' surface (as it should) and thus it gives it a solid infill depending on your 'bottom layers' setting.

Now this can be good, like your example, where it reinforces the edge.

But it can be a bad thing too and result in even more curling.. which is my experience - I'll try to explain this (but I should actually make an image to really explain it)
- imagine a pointy overhang
- it prints the shells, all good (these pointy parts normally curl upwards a bit, but with the amount of cooling I have this is not an issue)
- then it prints the 'bottom' layers (reinforcing) - in result it moves the head towards that pointy part which puts heat into that pointy area again! Thus curling up the corner more than it should!

Hope that makes sense. Still, this is only my theory based on my examinations. But I'm 99% certain that the additional heat being transfered in the workpiece does more bad than that additional blob of plastic (reinforcement) does good.

I think the right way to print this piece is by using 3 processes:
1 process for the base, normal settings
1 process for the slope-part, no infill, no bottom layers, no top layers - also lower down the speed (travel speed too!) a bit just for the double helix
1 process for the top, normal settings again

Like many other things, I will do exactly this as soon as I have time~! (Man I wish I could just 3D print all day long!)
Currently busy with getting rid of the vertical ridges/vibrations.. making some good progess, but still need to do a few tests. Also will give you guys an update of the advantages/disadvantages of upgrading my firmware as soon as I've done all the tests

[curious aardvark]

Like many other things, I will do exactly this as soon as I have time~! (Man I wish I could just 3D print all day long!)

Ain't that the truth :-)

[curious aardvark]

well printed the rook again from s3d.
Wow - some difference. Did one at 75% and one at 50% - don't have the 75% one anymore lol
gave it to someone this afternoon.
But it was pretty impressive.

When I get the battery back in my camera I'll take a couple pics of the 50% one.
Massive improvement over the one I did with makerware.
The side spirals are all smooth none of the crap I got with makerware. The dna spiral is clean, no touching areas, the stairs are sharp and the crenellations are definitely not rabbit poop ;-)

I did try a 25% one at 0.12 - but need to either recalibrate the printer or try and print the first couple layers at 0.2 and then the rest at 0.1 or whatever. Kinda like using a raft but without wasting any plastic.
I should be able to do that with two processes, right ?

[Dargonfly]

well printed the rook again from s3d.
Wow - some difference. Did one at 75% and one at 50% - don't have the 75% one anymore lol
gave it to someone this afternoon.
But it was pretty impressive.

When I get the battery back in my camera I'll take a couple pics of the 50% one.
Massive improvement over the one I did with makerware.
The side spirals are all smooth none of the crap I got with makerware. The dna spiral is clean, no touching areas, the stairs are sharp and the crenellations are definitely not rabbit poop ;-)

I did try a 25% one at 0.12 - but need to either recalibrate the printer or try and print the first couple layers at 0.2 and then the rest at 0.1 or whatever. Kinda like using a raft but without wasting any plastic.
I should be able to do that with two processes, right ?

Sound good! Looking forward to the images!

Yes, you can use two processes and set one up with 0.2 for first 1mm, then take over with over on 0.1mm for 1mm and beyond (it's under Advanced tab of Advanced (so... super Advanced?!))
If it is adhesion or general 'ugly layers' then you could also try starting with a higher temp, and gradually lowering it over the first few layers (helps me a lot with my crappy bend builplate.) That can be done in one process by adding several temperature setpoints.
Good luck!

[curious aardvark]

nah it's just calibrating the bed tight enough for 0.1 to work.
If I do that then use 0.2 the bastard sticks too much :-)

Plus I like the idea of mixing resolutions in a single print. That i can see being useful in the future.

At the moment I'm printing this pla at 195 with no issues of any kind.
It's seriously good stuff. It's reprapper tech ltd brand. Costs a wee bit more (£5 per kg) than the cheapest on ebay - but given how easy it is to use, zero shrinkage or warping and just plain damn nice to print with. I figure it's worth the extra money.

here's the small rook.

holdingrook_800x600.jpg

topdown_620x600.jpg

onits side_800x600.jpg

nice shot of the spiral

spiralshot_455x600.jpg