how do you minimap a model?

well i've been trying to make a more detailed gun on roblox studio via. minimapping but i can't find out whats wrong with this script

scale = 1 / 11

local representation = Instance.new("Model")
representation.Parent = script.Parent
representation.archivable = false
representation.glock = "Model"

function makeRepresentation(obj, cf, glock)
    if not obj.archivable then
        return 
    end
    if ((obj.className == "Part") or (obj.className == "Seat") or (obj.className == "SpawnLocation")) then
        local rep = Instance.new("Part")
        rep.formFactor = "Symmetric"
        rep.Size = obj.Size * scale
        rep.Transparency = obj.Transparency
        rep.Reflectance = obj.Reflectance
        rep.BrickColor = obj.brickColor
        rep.Anchored = true
        rep.Locked = true
        rep.TopSurface = Enum.SurfaceType.Smooth
        rep.BottomSurface = Enum.SurfaceType.Smooth
        rep.Shape = obj.Shape
        rep.glock = obj.glock
        mesh = Instance.new("SpecialMesh")
        mesh.Scale = obj.Size * scale / rep.Size
        local list = obj:GetChildren()
        local objMesh = nil
        for x = 1, #list do
            if (list[x].className == "Decal") then
                local copy = list[x]:Clone()
                copy.Parent = rep
            elseif (list[x].className == "SpecialMesh") or (list[x].className == "CylinderMesh") or (list[x].className == "BlockMesh") then
                objMesh = list[x]
            end
        end
        if objMesh ~= nil then
            mesh:Remove()
            mesh = objMesh:Clone()
            if (objMesh.className == "SpecialMesh") and (objMesh.MeshType == Enum.MeshType.FileMesh) then
                mesh.Scale = objMesh.Scale * scale
                mesh.Offset = objMesh.Offset * scale
            else
                mesh.Scale = objMesh.Scale * obj.Size * scale / rep.Size
                mesh.Offset = objMesh.Offset * scale
            end
        elseif obj.Shape == Enum.PartType.Ball then
            mesh.MeshType = Enum.MeshType.Sphere
        elseif obj.Shape == Enum.PartType.Block then
            mesh:Remove()
            mesh = Instance.new("BlockMesh")
            mesh.Scale = obj.Size * scale / rep.Size
            --mesh.MeshType = Enum.MeshType.Brick
        else
            mesh.MeshType = Enum.MeshType.Cylinder
            rep.Shape = Enum.PartType.Ball
        end
        mesh.Parent = rep
        rep.CFrame = cf:toWorldSpace(obj.CFrame + obj.Position * (scale - 1))
        rep.Parent = representation
    else
        if (obj == workspace) or (((obj.className == "Model") or (obj.className == "Tool") or (obj.className == "Hat")) and (obj ~= representation)) then
            local list = obj:GetChildren()
            for x = 1, #list do
                wait()
                makeRepresentation(list[x], cf, name .. "->" .. list[x].Name)
            end
        end
    end
end

local _, t = wait()
print("Reducing...")
makeRepresentation(workspace, CFrame.new(0, 1.2, 0), "Workspace")
local _2, t2 = wait()
print("Done! Time taken: " .. t2 - t .. " seconds.")

it's appreciated if i can get some help with this because i dont really understand scripting :/