01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
crc32(data, len)
>> 0x00FF: ACK
schedule(task, interval)
lock.acquire()
>> SYNC COMPLETE
release(ptr)
0x00 0x00 0x00 0x01
watchdog.reset()
>> LINK ESTABLISHED
fn poll(&mut self) -> Poll
waker.wake_by_ref()
cx.waker().clone()
01101001 01101110
fn init() -> Result<()>
for x in 0..buf.len()
load(addr, 0xFF)
sys.run(0x4A, flags)
if val > 0 { dispatch() }
>> 0x00: READY
loop { poll(); yield; }
stream.flush()
0xDEAD :: 0xBEEF
bind(sock, &addr, len)
pub fn connect(host: &str)
match state {
State::Init => boot(),
State::Run => tick(),
_ => halt(),
}
reg[0x3] = 0b11001010
clk.tick()
assert!(val != null)
>> SIGNAL RECEIVED
buf[i] ^= key[i % klen]
let n = read(fd, buf, 64)
while !done { step(); }
push(stack, frame)
0x7F :: OK
type Handler = fn(Ctx)
emit(Event::Data, payload)
select! { rx => handle(rx) }
spawn(async move { run() })
>> 0x01: PROCESSING
map.insert(k, v)
drain().collect::<Vec<_>>()
let _ = tx.send(msg)
timeout(Duration::ms(100))
>> CHECKSUM PASS
fn encode(src: &[u8]) -> Vec
pipe.write_all(&frame)
INDIGO-NX// DEV LOG
← JOURNAL
PUBLIC8 min read

478,000 Lines of Gcode — And What They Told Me

3d-printingklippermakerhardwareclaude-code
Creality CR20 Pro rebuilt with BTT Manta M8P and Klipper — BLTouch probe, TMC2209 drivers, rewired and ready

About a year ago I rebuilt a dead Creality CR20 Pro. New brain — a BigTreeTech Manta M8P running Klipper. New drivers — TMC2209s in StealthChop on the axes, SpreadCycle on the extruder. BLTouch for bed levelling. The whole thing rewired, reflashed, and ready to print. It's been running since, tuned and retuned multiple times.

Recently I let my AI co-engineer take a full pass at rewriting the printer.cfg from the ground up. First print after the new config: a Parkside-to-Makita battery adapter. Functional part, needs to hold together under load. Sliced it in OrcaSlicer and hit print.

Creality CR20 Pro spec plate — 220x220x250mm build volume, 270W, FDM, 1.75mm PLA

Then I looked at the gcode.

The Problem You Can Hear

The printer sounded wrong. Sharp jerky moves between layers. Moments where the head would crawl at a careful pace, then snap to something violent. Not the smooth hum of a tuned machine — more like a printer arguing with itself about how fast to go.

So I opened the gcode. All 478,833 lines of it.

What The Gcode Showed

I wrote a quick analysis to pull every feedrate command and map where speed changes happened. The results were ugly.

The worst offender: F600 to F9240 transitions. That's a 15.4x speed ratio, happening at overhang boundaries where the slicer drops to a crawl for overhangs then immediately snaps back to full speed for the next feature.

F600  → overhang at 75% (10 mm/s)
F9240 → inner wall right after (154 mm/s)

On a bed-slinger like the CR20 Pro, that's the Y axis slamming from a crawl to full tilt with a heated bed as the moving mass. The input shaper wasn't calibrated. The pressure advance was missing entirely from the config. The printer had no tools to handle those transitions gracefully.

There were 7,115 lines with F600 commands on extrusion moves — thousands of moments where the printer was creeping along at overhang speed and then being told to sprint.

The Arachne Problem

OrcaSlicer uses Arachne — a variable-width extrusion engine that adjusts wall thickness to fill gaps cleanly. It's clever. It also generated 4,482 micro-moves in this single print — tiny segments where the nozzle barely moves but changes direction.

With a resolution setting of 0.012mm (the default), Arachne was producing segments so small that the printer was spending more time processing commands than actually moving. On a 32-bit MCU that's already handling pressure advance and input shaper calculations, that's asking for trouble.

The Fix: OrcaSlicer

Four changes in the slicer profile:

Overhang speeds — raised from 10mm/s at 75% overhang to 20mm/s, and 30mm/s at 50% overhang to 40mm/s. Still cautious enough for clean overhangs, but the speed ratios between overhang and normal printing dropped from 15x to something manageable.

Resolution — 0.012mm to 0.02mm. Still well under visible quality thresholds, but enough to collapse those micro-moves from Arachne into segments the firmware can actually process smoothly.

Wall speeds — outer wall dropped to 80mm/s with 1000 mm/s² acceleration. Inner walls to 150mm/s at 1500 mm/s². A bed-slinger with an uncalibrated input shaper has no business running walls at 3000 mm/s² acceleration.

Extrusion rate smoothing — enabled at 10 mm³/s² across all features. This is the big one. Instead of allowing instant volumetric flow changes (which a bowden extruder can't physically deliver), the slicer now ramps flow rate gradually. The pressure advance in Klipper handles the rest.

The Fix: Klipper

The printer.cfg was missing critical sections. Not broken — just incomplete. The kind of config you get when you flash firmware and immediately start printing.

Pressure advance — added at 0.5 as a starting point. On a bowden tube, the filament compresses in the tube like a spring. Without PA, you get blobs at the start of moves and gaps at the end. Typical bowden range is 0.4–0.8; this needs a proper tuning tower to dial in.

Input shaper — added with placeholder values (35Hz MZV on both axes). The real fix here is an ADXL345 accelerometer mounted to the toolhead, running SHAPER_CALIBRATE to find the actual resonant frequencies. The accelerometer is bought, just not wired yet.

Bed PID — the bed heater was running in bang-bang mode (watermark control). Full power until target, off until it drops, repeat. PID holds temperature with fine adjustments instead of slamming between on and off. Needs a PID_CALIBRATE HEATER=heater_bed TARGET=55 run.

Bed mesh — upgraded from 3x3 to 5x5 probe points. Nine points isn't enough to map a bed that's been through thermal cycles.

Acceleration — max_accel raised from 1500 to 3000. Sounds aggressive for a bed-slinger, but with input shaper properly calibrated (once the ADXL is wired), this is well within what the frame can handle. The shaper absorbs the ringing that high accel would otherwise cause.

The Filament Profile

The OrcaSlicer filament profile was set to a generic "Aliz" vendor — not matched to the actual filament on the spool. Elegoo black PLA runs best at 200–210°C; the profile had 220°C set for both first layer and subsequent layers. Hot enough to work, but hot enough to cause stringing and make pressure advance harder to tune because the filament is more fluid than it should be.

The max volumetric speed was set to 12 mm³/s — reasonable for a stock hotend with a 0.4mm nozzle. That's actually the real speed limiter on this machine. Set your walls to 200mm/s if you want — the slicer will throttle back to stay under 12 mm³/s regardless.

Pressure advance in the filament profile was disabled (checkbox unchecked), which is correct — Klipper handles PA at the firmware level. Running PA in both the slicer and the firmware would double-compensate and make things worse.

The Result

Resliced with the updated profile. The gcode went from 478,833 lines to 701,791 — longer file, but that's because extrusion rate smoothing adds intermediate speed commands to ramp gradually instead of jumping.

The number that matters: F600 on extrusion moves dropped from 7,115 to 70. A 99% reduction in the speed transitions that were causing those sharp jerky moves.

The print time went from 3h8m to 3h43m. Thirty-five minutes longer. That's the cost of smooth motion — and it's worth it for a part that needs to survive mechanical load.

What I Learned

  1. Your slicer profile is half the firmware. A perfectly tuned Klipper config can't save you from a slicer that's commanding 15x speed jumps between adjacent features. Tune them together or don't bother.

  2. Overhang speeds are the biggest source of speed discontinuities. The defaults are set for printers that can handle instant transitions. A bed-slinger with a heavy heated bed on the Y axis cannot. Raise the floor, don't just lower the ceiling.

  3. Arachne's micro-moves are invisible until you count them. 4,482 tiny segments in a single print, each one a direction change the MCU has to process. Raising resolution from 0.012 to 0.02mm collapses them without visible quality loss.

  4. Bowden pressure advance isn't optional. Without it, every speed transition produces a blob or a gap. The tube compresses. Physics doesn't care about your firmware version.

  5. Max volumetric speed is the real speed limit. Wall speed settings are aspirational. The hotend's melt rate decides what actually happens. Know your number.

What's Next

The config is written but not deployed. The calibration sequence is:

  1. Back up the current config on the Pi, deploy the new one
  2. PID calibrate the bed heater
  3. Wire the ADXL345 accelerometer and run input shaper calibration
  4. Print a pressure advance tuning tower
  5. Flow rate calibration
  6. Retraction test

Once the input shaper has real resonance data instead of placeholder values, the acceleration limits open up. That's when the bed-slinger starts to feel like a different machine.

Parkside-to-Makita battery adapter mid-print on the CR20 Pro — supports visible, functional part taking shape

The adapter is printing now. If the fit is off, the parametric model in Fusion 360 is ready to adjust. That's the loop — slice, analyse, tune, print, measure, adjust. The printer is the tool. The gcode is the truth.

Tuned and analysed with Claude Code. Built at the bench.

// FEEDBACK

COMMENTS

Anonymous comments need approval before they appear. Log in for instant posting.
← BACK TO JOURNAL