YAST (Yet Another Support Thread)

[jdg56]

I've been poking around the entire forum, and it may be that my search-fu is not strong, but I'm not finding what I'm looking for. I'm really starting to get really buggy about supports / rafts.

I'm having weather-related issues with printing lately. During the warm summer, I was nailing my ABS prints, and my PLA was just about as good. Once the weather cooled down for Autumn, all of a sudden, PLA is curling up like a potato chip, and I'm being forced to use rafts for just about everything.

I just cracked open a new spool of Sainsmart white PLA, and am printing my usual new filament test objects; the 20mm cube and a garden gnome. The gnome has an overhang at butt level that is problematic with PLA, and actually requires support or it turns into a yarnball of filament

replicatorg, unfortunately, a) won't print support without rafts, and b) looks rather like the scaffolding they put around the statue of liberty by the time it's done building things, and actually runs support up to the nose of the damn gnome in the front. Way too much support, if you ask me.

Putting aside the welded on rafts, I'd like to try to tweak the supports in the gcode profile. I tried to tweak it a little bit, but I can't really puzzle out the features that well, and, of course, there's no documentation to explain what any of the bits actually do.

Has anyone done a profile edit with better (lighter) supports? If so, can you post a screenshot of the relavent changes?

Thanks in advance if anyone has fought with this and won.

Cheers,

John

[jdg56]

It's amazing how just asking a question causes one to find at least some sort of answer.

http://fabmetheus.crsndoo.com/wiki/i...keinforge_Raft

Is documentation for using rafts/supports.

Apparently, you can edit your gcode profile to set the base layers and interface layers to '0' in the rafts base and interface sections, and you'll print supports with no raft. That alone is a very find bit of information.

Yeah, there's some good information in that page. Thanks for bearing with the question, and hopefully there's some even better answers out there.

Cheers,

John

p.s.: This is known as 'garage mechanic syndrome'. It's like that noise that bothers the heck out of you and won't go away until you turn into the driveway of the local garage...

[Mjolinor]

p.s.: This is known as 'garage mechanic syndrome'. It's like that noise that bothers the heck out of you and won't go away until you turn into the driveway of the local garage...

It's the same law that dictates that items off ebay from China will not arrive until a few hours after you have sent an email to the seller saying you haven't got your bits.

[curious aardvark]

I'd suggest trying makerware - I thought rep-g was one of the worst pieces of software I've ever used.
Makerware isn't too bad and much better for raft and support control.

But the good version has disappeared from the makerbot site.

I'#ve got a copy of the decent one - maybe we could get it stickied on the forum ?
Geoff ???

[jdg56]

I use both. Since I'm a linux user, I don't have the same reserverations some have here about printing over the USB connection. My Makerare instance has a devil of a time actually connecting with the printer, so for my quick tests and general use, I just run replicatorg.

I've just started trying to tweak the raft/support settings. I tried to adjust the 'thickness' of the raft, and wound up slowing down the raft generation to the point where I had to cancel because I was convinced it was actually not even running correctly.

If I get a better raft out of skeinforge, I'll post the raft/support page setting I use. I'm actually not holding my breath, though.

Cheers,

John

[jdg56]

Hi all,

I realize that this forum has become a simplify3d shop ( I'm likely to acquire it soon myself), but for those who wish to retain some level of exposure to replicatorg, I thought I would share the results of some recent research.

As we all know, rafts and supports in replicatorg suck most heinously, and are the bane of using that tool for any task other than printing either cylinders or tapered pyramids. Unfortunately, due to a recent upgrade in my computing platform of choice, I can no longer directly use makerware (I hope they update it soon to work with my shiny new Ubuntu 14.10 installation), so I'm stuck with using replicatorg for my direct printing).

I realize also that printing from the SD card is many folk's preferred way to work. I happen to like usb printing, and have not had any issues with doing so, so I'll likely continue.

So, in cruising through the documentation for skeinforge, I found a few tidbits, like how to turn off rafts whilst still being able to generate supports. That solved the welded-on raft problem I'm sure we all know so well. As long as the project sticks to the build plate, all is well.

In the gcode menu of replicatorg, you can create and edit slicing profiles to accomodate your own workflow. Simply duplicate an existing profile, and then edit it. The edit window is a wicked maze of buttons that switch between dozens of pages of parameter settings windows. The buttons are in alphabetical order, so if you follow along until you find the 'raft' button (3rd from the left, 3rd down in my skeinforge 50 setup), click on it, and you'll see the applicable page to modify for rafts and support.

There are five (5) major sections of the settings page: 'Base', 'Interface', 'Name of Alteration Files', 'Raft Size', and 'Support'.

If you change the value for 'Base Layers' in the Base section to '0', and for 'Interface Layers' in the Interface section to '0', that will turn of raft generation.

This is helpful, but the supports are still massive and welded tightly to the object, so some further modifications are required.

To generate much more moderate supports, you need to modify three values.

In the Interface section, the 'Interface Infill Density (ratio)' default is '0.4'. I lowered this value to '0.3' and the supports are lighter and less robust.

In the Support section, the 'Support Flow Rate over Operating Flow Rate (ratio) also seems to affect how thick the supports are. The stock value is '0.7'. I dialed this down to '0.6'.

Lastly, the 'Support Gap over Perimeter Extrusion Width (ratio)' value has a default of '0.05'. I can only assume that this is a typo, as the net effect of this parameter is to define how far away from the edge of your printed object the supports should be placed. The default value of '0.05' basically says, overlap the support with the outside edge of the object, clinging to it like an obsessive ex-SO. I changed this value to '0.5', and my supports are a very fine, but discrete distance from the outside edge of the object. Absolutely close enough to give support to any vertical bit printed above it, but not touching the vertical bits of the object.

I've tested this with 3 or 4 recent prints, and the results are a major improvement over the stock settings.

I hope this is useful to someone out there.

Cheers,

John

[DrUsual]

Thanks JDG!

[FrankV]

Useful "finds" John, thank you for sharing.

Regarding this parameter:

Lastly, the 'Support Gap over Perimeter Extrusion Width (ratio)' value has a default of '0.05'. I can only assume that this is a typo, as the net effect of this parameter is to define how far away from the edge of your printed object the supports should be placed. The default value of '0.05' basically says, overlap the support with the outside edge of the object, clinging to it like an obsessive ex-SO. I changed this value to '0.5', and my supports are a very fine, but discrete distance from the outside edge of the object. Absolutely close enough to give support to any vertical bit printed above it, but not touching the vertical bits of the object.

In my setup and your posted screenshot, the default value is 0.005 (not 0.05), so did you change yours to 0.05 or 0.5 to get the desired result?

Frank

[jdg56]

Useful "finds" John, thank you for sharing.

Regarding this parameter:


In my setup and your posted screenshot, the default value is 0.005 (not 0.05), so did you change yours to 0.05 or 0.5 to get the desired result?

Frank

You are correct, and I used to type with a reasonable degree of accuracy. The value I use is 0.5, not 0.05. I just ran my last Thanksgiving pumpkin centerpiece last night, and even at 0.5, there's still a tiny bit of welding on a few bits of it. I may try to raise that value to 0.4 or 0.3 as a further test.

However, at 0.5, it's still a lot better than the default.

Cheers,

John

[jdg56]

Hi all,

It's been a while, but I thought I would toss out another tidbit for those of us who can't justify the cost of S3D.

I'm using replicatorg for most of my printing. I do sometimes tinker with makerware, but mostly use replicatorg (sailfish, for my creator pro), which slices with skeinforge.

I've been having first-layer issues lately, and went through a rather annoying stretch where I was trying to print some heart-shaped boxes as give-aways for a wedding I was attending. The casualties in my battle with flat tops and bottoms were staggering.

Way too late, I started to do some research on using brims/skirts, which do exist in skeinforge, but which are exactly one perimeter wide. Not much brim, if you ask me.

With some judicious googling, I found this link:

http://forums.reprap.org/read.php?1,136147,163334

Wherein a new version of the 'skirt.py' plugin for skeinforge adds a parameter to define how wide a brim you want to use.

The replacement 'skirt.py' works well in my setup. There's a different version about 70% of the way down the page, 'skirt_with_brim.py', that draws the brim from the outer edge to the inner, which seems to be more efficient.

To use brims, go to the directory in your replicatorg directory tree that is:

.../replicatorg-0040r28-Sailfish/skein_engines/skeinforge-50/skeinforge_application/skeinforge_plugins

All the definitions for various slicer functions are in a directory called 'craft_plugins'.

I made a backup directory, and copied the file 'craft_plugins/skirt.py' into that backup directory, just in case.

Copy the new brim-enabled skirt.py into craft_plugins. If you use the 'skirt_with_brim.py' plugin, rename it to 'skirt.py'.

Fire up replicatorg, open the gcode->edit slicing profiles menu, and duplicate an existing profile. In that new profile, select the 'skirt' button.



The 'Gap over perimeter' defines how close the brim will be to the work piece. I set it to 0.1, and it just kisses the edge of the object.

The 'Brim Width' defines how wide you want your brim to be.

I hope you find this useful.

Cheers,

John