First time modifying a cylinder

[STOVE]

I am getting ready to start a 290-390 conversion.

The Dukes cylinder that showed up has a few things that need to be addressed. However for the price i am very satisfied. Below are a few of the items that i was hoping to massage.

There is a slight lip all the way around the intake port. Can I use files and gradual grit sandpapers to clean this up?

The exhaust port needs a polish and edges cleaned up. Will polish this with a dremel. I don’t know if the shape is optimal however I will take off any lip or rough edge with some file and sandpaper work

The transfers have very sharp and somewhat uneven edges on one side. Will likely use small finger length files to round off these sharp edges.

Am I being too ambitious here in thinking I can use metal files? I am worried with it being my first time I will take away too much material attempting to use the dremel. Any help would be appreciated. I do have a Poulan 40cc jug I planned on practicing on with the files first.

 

[STOVE]

Photos of cylinder

 

[redneckhillbilly]

I'm glad you asked about the finger nail files, I had a thought about using those as well but didnt know where/when to ask. I am curious about what the pros have to say. THANKS

 

[hacskaroly]

I would think it would be too easy to take too big of a bit with a file than it would be to use a Dremel or other spinny tool. Might be able to use really fine grit sand paper (1200 or 1600) and lightly work around the edges to smooth them. That's just my though though. I have only used sand paper, green scotchbrite and brake hones in cylinders (only cleanup, no modifications).

 

[EFSM]

That lip is likely the cylinder plating intruding into the port. Some people have had trouble with the plating peeling off after modifying the ports. I have no experience with aftermarket cylinders, which I am fine with.
To your question: use a Dremel with a diamond cylindrical shaped bit (there are assortments available for cheap on Amazon or eBay) to take the burr off and then a ball or egg shaped to put the bevel/chamfer back on. I always finish with 600 or 1000 grit sandpaper though. https://www.amazon.com/Grinding-Dia...-2-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1