Plastic drain pipe screwed access plug removal

[brian_mk]

My house (built in the 1980s) has number of solvent welded screwed access plugs to clean the drain pipes in the bathroom, kitchen etc.
They are similar to the polypipe one shown below but have a lower profile cross shaped grip which makes them difficult to remove and refit.
Is there a special tool available to remove them without damage?
They are usually too tight to unscrew by hand. Adjustable grips tend to chew up the plug.
I thought about making something from a 40mm wooden dowel with a couple of saw cuts in the end in the shape of a cross.

 

[WC1]

There isn't a special tool as far as I'm aware. Have you thought of putting a little silicone grease on the lower part when you do them up (but obvs keep it off the part you grip.) Would keep them from binding. Large (300 mm+) pump pliers on the rim to loosen.

 

[ShaunCorbs]

Any reason why your removing the caps ?

 

[Ric2013]

I suspect they are similar to the head of the brass trap access plugs. A case of changing the material but not yet the design?

With four little nibs like on these traps?

 

[Ric2013]

I thought about making something from a 40mm wooden dowel with a couple of saw cuts in the end in the shape of a cross.

With a Jubilee clip around the dowel to stop it splitting, that might be the winning idea.