From 1d3847d5e5fc0a00dde18a713ca5161590443d3a Mon Sep 17 00:00:00 2001
From: Zxaber <37497534+zxaber@users.noreply.github.com>
Date: Sun, 17 Nov 2019 20:04:29 -0800
Subject: [PATCH 1/3] Fixed

---
 code/game/objects/items/stacks/stack.dm | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/code/game/objects/items/stacks/stack.dm b/code/game/objects/items/stacks/stack.dm
index 285647aaec7..b71b1a22073 100644
--- a/code/game/objects/items/stacks/stack.dm
+++ b/code/game/objects/items/stacks/stack.dm
@@ -413,6 +413,8 @@
 	if(!use(amount, TRUE, FALSE))
 		return FALSE
 	var/obj/item/stack/F = new type(user? user : drop_location(), amount, FALSE)
+	for(var/i in F.custom_materials)
+		custom_materials[i] -= F.custom_materials[i]
 	. = F
 	F.copy_evidences(src)
 	if(user)

From d0d5a2adfbc57531fc00c8adaa67aa2b67a88d50 Mon Sep 17 00:00:00 2001
From: Zxaber <37497534+zxaber@users.noreply.github.com>
Date: Sun, 17 Nov 2019 22:29:23 -0800
Subject: [PATCH 2/3] more fix

---
 code/game/objects/items/stacks/stack.dm | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/code/game/objects/items/stacks/stack.dm b/code/game/objects/items/stacks/stack.dm
index b71b1a22073..c7b05840f9f 100644
--- a/code/game/objects/items/stacks/stack.dm
+++ b/code/game/objects/items/stacks/stack.dm
@@ -225,6 +225,8 @@
 		if(O)
 			O.setDir(usr.dir)
 		use(R.req_amount * multiplier)
+		for(var/i in custom_materials)
+			custom_materials[i] = amount * mats_per_stack
 	
 		if(R.applies_mats && custom_materials && custom_materials.len)
 			var/list/used_materials = list()

From 58f9a8202003cb7e5ece80a2202d4fb118936fdc Mon Sep 17 00:00:00 2001
From: Zxaber <37497534+zxaber@users.noreply.github.com>
Date: Sun, 17 Nov 2019 22:35:06 -0800
Subject: [PATCH 3/3] Wait, this is better in the use proc

---
 code/game/objects/items/stacks/stack.dm | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/code/game/objects/items/stacks/stack.dm b/code/game/objects/items/stacks/stack.dm
index c7b05840f9f..f29f8fdeb67 100644
--- a/code/game/objects/items/stacks/stack.dm
+++ b/code/game/objects/items/stacks/stack.dm
@@ -225,8 +225,6 @@
 		if(O)
 			O.setDir(usr.dir)
 		use(R.req_amount * multiplier)
-		for(var/i in custom_materials)
-			custom_materials[i] = amount * mats_per_stack
 	
 		if(R.applies_mats && custom_materials && custom_materials.len)
 			var/list/used_materials = list()
@@ -317,6 +315,8 @@
 	amount -= used
 	if(check)
 		zero_amount()
+	for(var/i in custom_materials)
+		custom_materials[i] = amount * mats_per_stack
 	update_icon()
 	update_weight()
 	return TRUE