How can I make the CFrame Angles not.. glitchy?

Hi, I've tried to make a "Surface Blast Doors", but my script everytimes make the doors open BUT not open. I use CFrame Lerp and it makes that like the doors are open and not moving, but for roblox it moves, it moves only like a 0.001 stud and I don't know how to fix it. Please help. There is my script.

local db = false
local open = false

script.Parent.ClickDetector.MouseClick:Connect(function()
    warn("Checking if SBD's are open..")
    if open == false then
        warn("SBD's closed, checking if in move!")
        if db == false then
            warn("SBD's not moving. Opening SBD's!")
            db = true
            local finish = script.Parent.Parent.PrimaryPart.CFrame*CFrame.Angles(0,math.rad(90),0)
            for i = 0,1,.00001 do
                local cfm = script.Parent.Parent.PrimaryPart.CFrame:Lerp(finish,i)
                script.Parent.Parent:SetPrimaryPartCFrame(cfm)
                wait()
            end
            open = true
            warn("\nSBD's SUCCESSFULLY OPENED!")
            wait(1)
            db = false
            warn("\nPrepared to close!")
        end
    elseif open == true then
        warn("SBD's opened, checking if in move!")
        if db == false then
            warn("SBD's not moving. Closing SBD's!")
            db = true
            local finish = script.Parent.Parent.PrimaryPart.CFrame*CFrame.Angles(0,-math.rad(90),0)
            for i = 0,1,.00001 do
                local cfm = script.Parent.Parent.PrimaryPart.CFrame:Lerp(finish,i)
                script.Parent.Parent:SetPrimaryPartCFrame(cfm)
                wait()
            end
            open = false
            warn("\nSBD's SUCCESSFULLY CLOSED!")
            wait(1)
            db = false
            warn("\nPrepared to open!")
        end
    end
end)

(The doors itself are the ClickDetector, I made that just for testing.)