Trying to decide best way to cut round gun ports into ship planking. Is it best to enlarge a drilled hole using files or to drill directly using something like a forstner bit. Worried about break-out on inside surface. Any suggestions on methodology, jigs, etc. Would be appreciated.
I would drill smaller hole and enlarged with the round file. Besides after making a first smaller hole I would apply diluted PVA everywhere in and around the hole and let it fully dry. This will prevent splits when doing a final filing.
A forstner bit would be dangerous to use for sure. I would start with a small bit drill and work out to enrage the hole using the next drill bit. To finish the hole for the required size, use sandpaper around the wooden dowel with a close diameter or round files.
- Joined
- May 27, 2021
- Messages
- 222
- Points
- 88
I've seen one guy where he would run the drill bit in reverse to avoid chipping. Start small and work up.
I would grind the hole out with a diamond bit on a Dremel tool, which removes wood quickly in a controlled manner, then file the finished edges with a rat tail file.
i have had success with a step bit it is a conical drill bit that increases in size . go through one side till you get to the size of hole you want then the other side to even the hole out. can be used on a drill or by hand locked in a vise grips. ( drill on low speed works better) cuts very clean with no tear-out. just start with a small pilot hole as a guide.