{"id":344,"date":"2026-09-29T10:19:05","date_gmt":"2026-09-29T09:19:05","guid":{"rendered":"https:\/\/askthenozzle.com\/blog\/how-to-fix-first-layer-adhesion-in-prusaslicer-the-settings-that-actually-matter\/"},"modified":"2026-10-05T09:08:35","modified_gmt":"2026-10-05T08:08:35","slug":"how-to-fix-first-layer-adhesion-in-prusaslicer-the-settings-that-actually-matter","status":"publish","type":"post","link":"https:\/\/askthenozzle.com\/blog\/how-to-fix-first-layer-adhesion-in-prusaslicer-the-settings-that-actually-matter\/","title":{"rendered":"How to Fix First Layer Adhesion in PrusaSlicer: The Settings That Actually Matter"},"content":{"rendered":"<p>Nine times out of ten, a bad first layer is a nozzle-to-bed distance problem, not a slicer flow problem. So before you start pulling levers all over PrusaSlicer, get your Z-offset right \u2014 then use the settings below to make a good first layer more forgiving, not to paper over a bad one. This is the practical order of operations for <strong>how to fix first layer adhesion PrusaSlicer settings<\/strong> control, with the exact values, the locations in the interface, and the mechanisms behind each one.<\/p>\n<p>A correctly dialled first layer looks slightly squished with no gaps between the extrusion lines. Too high and the plastic never presses into the surface to grip it; too low and the nozzle drags through the plastic, causing scratches, jams and an over-wide, ridged base. Everything else here assumes you&#8217;ve hit that baseline first.<\/p>\n<h2>Start with Z-offset \u2014 the real root cause<\/h2>\n<p>PrusaSlicer assumes the tip of the nozzle sits at Z=0 on the bed. The <em>actual<\/em> gap between nozzle and bed is set on the printer (Live Adjust Z on Prusa machines, or your printer&#8217;s Z-offset in Klipper\/firmware), not in the slicer. If that gap is wrong, no slicer setting will save you.<\/p>\n<p>Dial it in with a single-layer test \u2014 a large, thin patch or the built-in first-layer calibration on Prusa hardware. Adjust in small steps until adjacent lines just merge into a solid sheet with no gaps and no visible ridging. Only once that&#8217;s correct should you touch flow, and only if your extrusion multiplier is genuinely miscalibrated. If you want a structured walk-through of <a href=\"https:\/\/askthenozzle.com\/blog\/3d-print-failure-diagnosis-tool-how-to-read-the-symptom-and-fix-the-right-cause\/\">reading the symptom back to the cause<\/a>, our <a href=\"https:\/\/askthenozzle.com\/blog\/prusaslicer-settings-to-fix-first-layer-problems-exact-values\/\">PrusaSlicer settings to fix first layer problems<\/a> guide lists the exact values to test.<\/p>\n<h2>First layer height: 0.20\u20130.25 mm, and why<\/h2>\n<p>Set <strong>First layer height<\/strong> under <em>Print Settings \u2192 Layers and perimeters<\/em>. Original Prusa print profiles always use 0.20 mm for the first layer, and that&#8217;s a sound default for a 0.4 mm nozzle. A thicker first layer is more forgiving of a slightly imperfect bed and lays down more plastic to grip the surface.<\/p>\n<p>The key habit: even if you&#8217;re printing fine detail at 0.10 mm layers, keep the first layer at 0.20 mm to boost adhesion. There&#8217;s no rule that the first layer must match the rest of the print.<\/p>\n<ul>\n<li><strong>Hard floor:<\/strong> on MK3-class machines the minimum first layer height is around 0.15 mm, owing to the software endstops.<\/li>\n<li><strong>Hard ceiling:<\/strong> keep layer height below 80% of nozzle diameter \u2014 about 0.32 mm on a 0.4 mm nozzle. PrusaSlicer won&#8217;t let you exceed the nozzle diameter at all.<\/li>\n<li><strong>Behaviour to know:<\/strong> PrusaSlicer does what you tell it. Unlike Simplify3D, it does not quietly re-tweak flow behind the scenes \u2014 if you specify 0.20 mm, it calculates flow and movement for exactly 0.20 mm.<\/li>\n<\/ul>\n<h2>First layer extrusion width: more contact, more grip<\/h2>\n<p>The more material touching the bed, the better the part adheres. You widen that contact with <strong>First layer extrusion width<\/strong>, which PrusaSlicer keeps in <em>Print Settings \u2192 Advanced<\/em>. Any spaces between extrusions are adjusted accordingly, so a wider first line means a denser, better-bonded base.<\/p>\n<p>You&#8217;ll see two schools of advice, and the difference matters:<\/p>\n<ul>\n<li><strong>The conservative value:<\/strong> 0.45\u20130.50 mm (roughly 120% for a 0.4 mm nozzle). Reliable across layer heights.<\/li>\n<li><strong>The classic 200% advice \u2014 with a caveat:<\/strong> the percentage is calculated from <em>layer height<\/em>, not nozzle diameter. Set 200% on a 0.10 mm first layer and you get a 0.20 mm line \u2014 narrower than the nozzle, causing poor flow and a failed print. 200% only makes sense combined with a tall first layer (0.20 mm+).<\/li>\n<li><strong>Set it to 0<\/strong> to let the slicer auto-calculate \u2014 fine, but slightly conservative.<\/li>\n<\/ul>\n<h2>First layer speed: 20\u201325 mm\/s<\/h2>\n<p>PrusaSlicer organises speed by feature, and the first-layer speed overrides every other speed category. Set it to <strong>20\u201325 mm\/s<\/strong> and move on. Slow gives the extruded plastic maximum time to bond to the bed before the head moves on. This is one of the highest-value, lowest-effort changes you can make.<\/p>\n<h2>Temperatures: run the first layer hotter<\/h2>\n<p>Run the first layer 5\u201310 \u00b0C hotter than the rest of the print so the plastic flows into the bed texture better. Nozzle first-layer temperature is a filament setting; bed temperature matters just as much and is often the real lever when corners lift.<\/p>\n<table>\n<thead>\n<tr>\n<th>Material<\/th>\n<th>First-layer nozzle<\/th>\n<th>Other layers<\/th>\n<th>Bed<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>PLA<\/td>\n<td>215 \u00b0C<\/td>\n<td>205\u2013210 \u00b0C<\/td>\n<td>55\u201360 \u00b0C<\/td>\n<\/tr>\n<tr>\n<td>PETG<\/td>\n<td>240 \u00b0C<\/td>\n<td>235 \u00b0C<\/td>\n<td>80\u201385 \u00b0C<\/td>\n<\/tr>\n<tr>\n<td>ABS \/ ASA<\/td>\n<td>250 \u00b0C<\/td>\n<td>245 \u00b0C<\/td>\n<td>100\u2013110 \u00b0C<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><strong>PLA bed-temp caution:<\/strong> hotter is not better here. PLA&#8217;s glass transition is around 60 \u00b0C. Above 65 \u00b0C the bottom layers stay soft throughout the print, deform under the weight above them, cause <a href=\"https:\/\/askthenozzle.com\/blog\/first-layer-adhesion-problems-the-real-causes-and-the-exact-fixes\/\">elephant&#8217;s foot<\/a> and make removal difficult. 55\u201360 \u00b0C is the sweet spot. If corners lift on PETG or ABS, raise the <em>bed<\/em> temperature, not the nozzle. For material-specific PLA troubleshooting, see <a href=\"https:\/\/askthenozzle.com\/blog\/first-layer-adhesion-issues-with-pla-the-real-causes-and-the-exact-fixes\/\">first layer adhesion issues with PLA<\/a>.<\/p>\n<h2>Cooling: keep the fan off early<\/h2>\n<p>The part-cooling fan is a <strong>filament<\/strong> setting in PrusaSlicer, adjustable per material under <em>Filament Settings \u2192 Cooling<\/em>. Cooling too soon makes the plastic contract and pull away from the bed \u2014 especially with PETG and ABS, which love to warp.<\/p>\n<p>Standard practice: <strong>disable the fan for the first two or three layers<\/strong> so you&#8217;re sure the print is securely attached before any cooling starts. For most materials the fan then maintains at least a minimum speed; ABS, ASA, PC and some flexibles typically run with it off entirely.<\/p>\n<p><strong>The gotcha to watch:<\/strong> dynamic\/overhang fan speeds can override &#8220;disable fan for first N layers.&#8221; If there&#8217;s an overhang on an early layer, the fan applies the dynamic speed anyway \u2014 which is bad for bed adhesion. If you&#8217;re fighting early lift on a part with low overhangs, check that dynamic overhang cooling isn&#8217;t quietly spinning the fan up.<\/p>\n<h2>Brim: contact area for warp-prone parts<\/h2>\n<p>Set brim width under <em>Print Settings \u2192 Skirt and brim \u2192 Brim<\/em>. A brim is the horizontal band printed around each object on the first layer \u2014 it massively increases contact area at the base and fights corner lift.<\/p>\n<ul>\n<li><strong>Minimum useful width:<\/strong> at least 3 mm to meaningfully help. Everyday prints commonly use 5\u201310 mm; around 8 mm for a strong hold on a lift-prone part.<\/li>\n<li><strong>Warp-prone parts:<\/strong> 3\u20135 mm brim with a <strong>Brim separation gap of 0.1 mm<\/strong> so it snaps off cleanly.<\/li>\n<li><strong>Brim type:<\/strong> outer, inner, or both. Inner brims fill enclosed holes in the footprint \u2014 useful for tall parts with internal cavities.<\/li>\n<li><strong>When it&#8217;s warranted:<\/strong> large flat prints (over 100 mm in any dimension), warp-prone filaments (ABS, ASA, nylon), or parts with small contact areas.<\/li>\n<\/ul>\n<p>A brim adds contact area and resists corner lift, but it won&#8217;t rescue a dirty bed or a wrong Z-offset \u2014 fix those first.<\/p>\n<h2>Elephant foot compensation: last step, not first<\/h2>\n<p>When the first layer is squished against the heated bed it comes out slightly wider than intended. <strong>Elephant foot compensation<\/strong> (<em>Print Settings \u2192 Advanced<\/em>, Advanced or Expert mode) scales the first layer inwards to correct that. Values around 0.2 mm usually work well for a 0.4 mm nozzle, and the setting takes a positive number for the amount to shrink. Official Prusa profiles ship with it on by default, and PrusaSlicer 2.2+ automatically detects thin first-layer lines so it doesn&#8217;t over-shrink them.<\/p>\n<p>Two things to know:<\/p>\n<ul>\n<li><strong>Brim interaction:<\/strong> the brim connects more weakly to the model when compensation is on. If your brim detaches mid-print, elephant foot compensation is a likely cause.<\/li>\n<li><strong>It hides a symptom, it doesn&#8217;t remove it.<\/strong> Compensation is the last step: level the bed, set Z-offset, set temperatures so the base firms up early \u2014 then add a touch of compensation only for parts that need a tight dimensional fit at the base.<\/li>\n<\/ul>\n<h2>Skirt: a diagnostic, not an adhesion fix<\/h2>\n<p>A 2\u20133 loop skirt at 1\u20132 mm distance primes the nozzle and lets you watch the first extrusion before the real part starts. It won&#8217;t fix adhesion on its own, but it tells you instantly whether flow is consistent \u2014 a quick sanity check before committing to a long print. Pair it with our <a href=\"https:\/\/askthenozzle.com\/preflight\">G-code pre-flight checklist<\/a> to catch problems before the printer even starts.<\/p>\n<h2>Put it in order<\/h2>\n<ol>\n<li>Level the bed and set Z-offset until adjacent lines merge with no gaps.<\/li>\n<li>First layer height 0.20 mm; extrusion width 0.45\u20130.50 mm (or 120%).<\/li>\n<li>First layer speed 20\u201325 mm\/s.<\/li>\n<li>First layer 5\u201310 \u00b0C hotter; correct bed temperature for the material.<\/li>\n<li>Fan off for the first 2\u20133 layers; check dynamic overhang cooling isn&#8217;t overriding it.<\/li>\n<li>Brim 3\u20135 mm for tall, narrow or warp-prone parts, 0.1 mm separation gap.<\/li>\n<li>Elephant foot compensation ~0.2 mm last, only if the base needs it.<\/li>\n<\/ol>\n<p>Work top to bottom and stop as soon as the first layer is clean. If you&#8217;re still guessing, upload a photo to our <a href=\"https:\/\/askthenozzle.com\/diagnose\">Diagnose tool<\/a> \u2014 it reads the defect and hands back concrete slicer changes, so you&#8217;re not burning filament testing one variable at a time. The same pre-flight and diagnostic engine is built into ATN Slicer if you&#8217;d rather it watched your back inside your normal workflow.<\/p>\n<h2>FAQ<\/h2>\n<h3>What is the best first layer height in PrusaSlicer for adhesion?<\/h3>\n<p>0.20 mm for a 0.4 mm nozzle \u2014 it&#8217;s the Prusa default and it lays down enough plastic to grip an imperfect bed. Keep it at 0.20 mm even when the rest of the print is finer, like 0.10 mm. On MK3-class machines you can&#8217;t go below about 0.15 mm.<\/p>\n<h3>Should I turn the fan off for the first layer in PrusaSlicer?<\/h3>\n<p>Yes. In Filament Settings \u2192 Cooling, disable the fan for the first 2\u20133 layers so the plastic bonds before any cooling starts. Watch out for dynamic overhang cooling, which can override this on early-layer overhangs.<\/p>\n<h3>Does a brim fix first layer adhesion?<\/h3>\n<p>It helps by adding contact area and resisting corner lift \u2014 use 3\u20135 mm with a 0.1 mm separation gap on warp-prone parts. But it won&#8217;t compensate for a dirty bed or a wrong Z-offset. Fix those first.<\/p>\n<h3>What does elephant foot compensation do, and should I use it?<\/h3>\n<p>It shrinks the first layer inwards (around 0.2 mm for a 0.4 mm nozzle) to correct the widening caused by squish against a hot bed. Use it last, only when the base dimensions matter \u2014 and note it weakens the brim-to-part bond.<\/p>\n<p><strong>Related:<\/strong> <a href=\"https:\/\/askthenozzle.com\/blog\/first-layer-adhesion-settings-in-prusaslicer-the-exact-values-that-make-prints-stick\/\">First Layer Adhesion Settings in PrusaSlicer: The Exact Values That Make Prints Stick<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Nine times out of ten, a bad first layer is a nozzle-to-bed distance problem, not a slicer flow problem. So before you start pulling levers all over PrusaSlicer, get your Z-offset right \u2014 then use the settings below \u2026<\/p>\n","protected":false},"author":1,"featured_media":343,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-344","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorised"],"_links":{"self":[{"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/posts\/344","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/comments?post=344"}],"version-history":[{"count":1,"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/posts\/344\/revisions"}],"predecessor-version":[{"id":365,"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/posts\/344\/revisions\/365"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/media\/343"}],"wp:attachment":[{"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/media?parent=344"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/categories?post=344"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/askthenozzle.com\/blog\/wp-json\/wp\/v2\/tags?post=344"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}