here is the issue from the JEI tracker, with the report: here

here is the crash report as well

stacktrace:

-- Item being rendered --
Details:
Item Type: mob_grinding_utils.ModBlocks$2@30a923bc
Item Aux: 0
Item NBT: null
Item Foil: false
Stacktrace:
at net.minecraft.client.renderer.RenderItem.renderItemAndEffectIntoGUI(RenderItem.java:342)

-- Item being rendered --
Details:
Item Type: mob_grinding_utils.ModBlocks$2@30a923bc
Item Aux: 0
Item NBT: null
Item Foil: false
Stacktrace:
at codechicken.lib.render.item.CCRenderItem.renderItemAndEffectIntoGUI(CCRenderItem.java:217)
at mezz.jei.plugins.vanilla.ingredients.ItemStackRenderer.render(ItemStackRenderer.java:28)

-- Ingredient being rendered --
Details:
Ingredient Mod: mob_grinding_utils
Ingredient Info: 1xtile.mob_grinding_utils.saw@0 mob_grinding_utils:saw
Stacktrace:
at mezz.jei.render.IngredientRenderer.createRenderIngredientException(IngredientRenderer.java:220)
at mezz.jei.render.IngredientRenderer.renderSlow(IngredientRenderer.java:74)
at mezz.jei.render.IngredientListBatchRenderer.render(IngredientListBatchRenderer.java:188)
at mezz.jei.gui.overlay.IngredientGrid.draw(IngredientGrid.java:90)
at mezz.jei.gui.overlay.IngredientListOverlay.drawScreen(IngredientListOverlay.java:209)
at mezz.jei.gui.GuiEventHandler.onDrawBackgroundEventPost(GuiEventHandler.java:74)
at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_3519_GuiEventHandler_onDrawBackgroundEventPost_BackgroundDrawnEvent.invoke(.dynamic)
at net.minecraftforge.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:90)
at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:182)
at net.minecraft.client.gui.GuiScreen.drawDefaultBackground(GuiScreen.java:575)
at

closing due to it not being this mod's issue by the looks of things.