diff --git a/machines/rotary_macerator.lua b/machines/rotary_macerator.lua
index feb86d0..db3e8b1 100644
--- a/machines/rotary_macerator.lua
+++ b/machines/rotary_macerator.lua
@@ -94,7 +94,7 @@ rotaryMacerator.onTimer=function(pos,elapsed,meta,inv)
 	shouldRerunTimer,shouldUpdateFormspec=industrialtest.internal.chargeFromPowerStorageItem(meta,inv)
 
 	if rpm>0 then
-		meta:set_int("rpm",math.max(rpm-1000,0))
+		meta:set_int("rpm",math.max(rpm-1000*elapsed,0))
 		shouldRerunTimer=shouldRerunTimer or rpm>0
 		shouldUpdateFormspec=true
 	end
@@ -200,7 +200,7 @@ rotaryMacerator.activeOnTimer=function(pos,elapsed,meta,inv)
 		meta:set_float("maxSrcTime",0)
 		srcSlot:set_count(srcSlot:get_count()-multiplier)
 		inv:set_stack("src",1,srcSlot)
-		meta:set_int("rpm",math.min(rpm+750,7500))
+		meta:set_int("rpm",math.min(rpm+750*elapsed,7500))
 		if modified then
 			local modifierMeta=modifierSlot:get_meta()
 			local uses=result.uses