BotHacker recently documented his adventures in cooling fans and Skeinforge options – to amazing effect. 1 You should read the entire post, because there’s a lot of good info in there. However, to summarize:
- Numerous permutations of cooling fan sizes and speeds offered some improvement.
- Using no cooling fans and putting the Skeinforge Cool setting at a minimum layer time of 10 seconds offered a dramatic improvement.
BotHacker’s post is what Skeinforge documentation should look like.
Update: Per BotHacker’s comment below, “Skeinforge must be told to ‘Slow Down’ for this to work. The other option is ‘Orbit’, and may lead to poorer results.”

Thanks for the kudos!
Don’t worry about the ‘all rights reserved’, we are very happy to see people using what we put out there. We’re fans of the Creative Commons Share Alike attributions.
The only thing I might add to your summary is that Skeinforge must be told to ‘Slow Down’ for this to work. The other option is ‘Orbit’, and may lead to poorer results.
Cheers!
[...] post about his adventures with Skeinforge. As with BotHacker’s excellent post about the Skeinforge Cool setting and analysis about the benefits of cooling fans, Gian’s post takes us through each of his Skeinforge changes as well as documenting [...]
I think “Slow Down” drops both the feed rate and flow rate to slow things down. I tried this on a small Thing over the weekend and on the really tiny layers, it just stopped extruding – I suspect because the flow rate had been turned down to a PWM where the extruder motor just stopped working.
For a non-stepper extruder like the current makerbots, “Slow Down” probably isn’t what you want to do.
The “Orbit” option works better but if you don’t have your oozebane/FW-reversal params set correclty, things are going to get a bit stringy.
[...] and sliding of layers. One effective method of reducing this problem is through the use of Skeinforge’s “Cool” setting. The Cool setting allows you to specify a minimum time the printer will spend working on a given [...]
[...] information and ideas on fighting the gooey layer problem, check out Bothacker’s work with Skeinforge’s Cool function and Tesla893′s idea of printing multiple copies of parts at once. Photo courtesy of [...]