I am remodeling a small bedroom at the back of my house. I decided to install two french pocket doors between this bedroom and another. I wish to extend an newer hardwood floor from the middle bedroom through the french door opening and into the smaller bedroom. The American Hickory floor boards run perpendicular to the wall, so new boards must be feathered in. As the door opening is 64" and the planks are 5", I have approximately 6 boards to cut (leaving h-joints) or more without h-joints.

I would like to use my Porter Cable variable speed plunge router to make clean cuts of the existing boards, which are quite long at appropriate intervals, but I am concerned about getting the cuts square and straight. In doing some research, I see that a slide or fence (not sure what to call it) can be used for this. I've attached an image grabbed from a BobVila.com video.

I have searched high and low for this tool, but can't seem to find anything. Does anyone know what to call this and where it might be purchased? Thanks in advance.
https://www.movesinstitute.org/~weekley/images/PlungeRouterFrameGuide.jpg

I know Dan Braucht (occasional contributor) uses some kind of jig with a router. Too bad I didn't get a chance to see it in action. It's really about cutting back each individual board that gets removed close to the side and end joints, then sliding and/or prying them out. The remaining pieces generally just pop out except for ones that still may have the fasteners in them. I've been able to just cut with a circular saw, close enough where the nails get cut at the same time...but older cut nails may pose a problem, something I've never encountered working in the south and mostly homes no older than 40 years.

getting a little too involved to just cut out a pattern..but that said you are merely cutting 5" on a few boards.

it would be cheaper to buy a roto zip or dremel..

but simplifying it for you..just tack a strait edge down..a 1X will do the trick..

just move it and retack it as you go.

Using a skill saw (set to woods thickness) make two cuts up the length of your boards, about 1/4-3/8" off the crack. Stop the saw just as the blade approaches the butt joint. This will create 3 sections in the board- groove, center, tongue.. You can make new (non tongue and groove) ends to avoid H joints1 with a framing square, oscillating plunge cut saw (fein), and a steady hand. Make all of those cuts before removing the wood. The centers should all come easy by being lifted from the free end, a chisel may be necessary to split the wood where the saw does not cut through the boards at the ends. Then the grooves will all come easy. If you got lucky you will have run your saw through the nails right where they penetrate the subfloor, but with some patience you will get it out.

Set all nails, clean up and start installing. Remember wood glue is a great lubricant if you work quickly to slide your boards in... if you are too slow it is a horrible lubricant.

This same method can be used to replace a board in the body of the floor with the addition of a cut connecting your current two skill saw cuts.

my impression is he is trying to form his own pattern and cutting his own butt joint pattern..not remove the actual pattern.( which would be the best but sometimes the lengths do allow it..)

or did I miss something?

for me circular all day would do this and complete the cut with a Fein.