Hi, I am Almost to your point in my cabinet. I did read on a thread that CitznFish had on his site. A guy used the #542 Carbide slot cutter Dremel bit for the t molding. He said it worked great but practiced first. I was going to use my dremel. I have not really used it since I got one for Christmas. I will be interested in what others have to say.
I went down this path and with patience, it can be done. Smooth groove that did not end up wavy as some might be lead to believe but you must work slowly both to ensure you keep path straight and do not burn up the dremel.
I used the carbide bit and did *not* use the router attachment. Rather, I set the depth with the standard offset attachment, turned the piece on its side and went to work.
If you have access to a router, it is certainly the tool of choice for such tasks assuming you acquire a slot cutting bit as well.
I've done all sorts of tasks with my dremel and its still going strong but if you are going to have to purchase one for this single task alone, you would be better off searching out a router option.
I use my dremel for lots of tasks including case mods, household chores, plexi signs, etc so it was something I already had including the carbide bit.
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