Help with figuring out what kind of router bits are needed for old trim Re-creation

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by Frozone816 posted 02-13-2018 09:44 PM 2798 views 0 times favorited 10 replies Add to Favorites Watch
View Frozone816's profile


3 posts in 956 days

02-13-2018 09:44 PM

Topic tags/keywords: router trim 1890s

Hi everyone!
I’m sorry if this isn’t the right forum to post this type of question but I’m new around here so if you can direct me to the right location I would greatly appreciate it!

My wife and I moved into a house about 10 years ago that was built in the 1890s and although mostly intact the bedroom as well as a couple of random spots are missing the original trim work. I just recently got into woodworking and although I have some knowledge, I am unsure as to how to remake the design of trim that is in our home.

The trim measures roughly 4 and 5/8 wide and round overs on both edges but with the inner Edge having an additional chunk cut out that’s roughly an inch deep. I have taken a number of photos to better relay what the profile looks like, but I can’t seem to find any type of router bit that would cut that actual profile out.

Any kind of help is greatly appreciated, and I look forward to seeing your replies!

10 replies so far

View RDan's profile


159 posts in 3178 days

#1 posted 02-13-2018 11:28 PM

If I was trying to do this. I would do a rabbet for the narrow part, then a small round over either a 1/4” or 3/8” and sneak up to it. It also looks like a relief cut on the lower back side. Dan

View Ripper70's profile


1378 posts in 1763 days

#2 posted 02-13-2018 11:42 PM

How much of this do you need? If just a short run or two to match existing trim, I might consider making it with two pieces sandwiched together. Round over profiles on the top edges of the tall and short piece, glue together then round over the bottom edge.

-- "You know, I'm such a great driver, it's incomprehensible that they took my license away." --Vince Ricardo

View hickory44's profile


1 post in 2204 days

#3 posted 02-13-2018 11:45 PM

Given the fact that this profile was made on a moulder, with custom ground knives, you will not likely find any
router bits that will match it. I would grind a set of knives for my shapter, but that does not help you! RDan’s
method is probably the easiest. A flat-bottom roundover bit ( like MCLS #5444, or similar) would help you
round over the step after you make the rabbet. The top edge roundover is easier. The back relief is important
as well, to bridge any differences in the wall plaster and the bottom plate on the wall. It does not have to be
pretty, so several passes over a dado head or a wide mortising bit will work.

View Frozone816's profile


3 posts in 956 days

#4 posted 02-14-2018 12:09 AM

Thank you all for your replies! I think I may consider doing the rabbet cut as suggested, in reply to Ripper, I need roughly 64 ft of this moulding, the molding that was all inside of the bedroom was replaced with a more modern style, and completely mismatches the rest of the entire house! This has three doorways and a window that all need replacing. If I can’t figure it out on the router table, I may just try your idea of butting two pieces together. When I get this project going I will make sure to share my progress!
Thanks again everyone

View Loren's profile


10597 posts in 4502 days

#5 posted 02-14-2018 12:20 AM

I’m not sure you’re dealing with strict roundover
and flat profiles, which complicates it.

However, if you aren’t butting the new moldings
up against old ones probably nobody will be able
to tell if they don’t match exactly.

The roundovers at the edges can be done with
standard roundover bits with bearings. These are
among the most useful router bits and I would
recommend you just buy a 4 or 5 piece set.

The roundover of the “step” can’t be done with
a bearing guided bit. You may be able to get the
effect you want using a “plunge roundover” bit if
you can find one short enough. Or buy a bearing
guided bit in the right size and grind off the
bearing nub.

View LesB's profile


2607 posts in 4297 days

#6 posted 02-14-2018 02:53 AM

For this limited production and assuming you have a table saw I would suggest finding some molding head cutter sets. Craftsman use to make them and I just check and they are still available inexpensively on eBay. I have made good use of them for this type of a problem. They are high speed steel so if there isn’t one already made you can grind you own shape. You will need to make a custom insert for your saw table and set up some hold downs on the saw to keep the wood in the proper position as you run it through. Don’t try to take off too much wood at a time, make a couple of passes or more and wear ear protection; it can be noisy. Assuming you will use a soft wood like pine of popular this will work quite well.

My approach would be to make the step flat and inner round over first and it would help if the board were slightly wider so you have some support on the outside of the step which you can cut off later. For the other two round overs you can use a router with a round over bit. It would be best to use a router table with a fence to control the cut; particularly for the step side which is not tall enough for a bearing guide.
There are two different types of shaper heads. One takes only one blade which would make it easier to customize the shape you want from a flat ended cutter. The other takes three cutters so you would need to make all three the same shape or at least close to the same because which ever one stands proud of the others will determine you final cut.

Here is a UTube video on using the shaper.

Here is a sequence of cuts to make. The last relief cut can be made using a flat cutter in the molder heat.

-- Les B, Oregon

View Frozone816's profile


3 posts in 956 days

#7 posted 02-14-2018 04:50 AM

Thank you! That was a very concise post! I appreciate all you put together.

View jimintx's profile


934 posts in 2439 days

#8 posted 02-14-2018 05:32 AM

LesB, that is a fantastic display of what your process would be.
I have no idea t all how to create such pictures with that sort of CAD work.

-- Jim, Houston, TX

View LesB's profile


2607 posts in 4297 days

#9 posted 02-14-2018 07:29 PM

LesB, that is a fantastic display of what your process would be.
I have no idea t all how to create such pictures with that sort of CAD work.

- jimintx

I used the free version of Sketchup to draw the images and with the screen capture feature on my Mac computer I took a picture of each step. On a Mac computer pressing the Shift>Command>4 keys changes the cursor to a “target” type icon. Move it to the upper left corner of the area of the screen you want to create an image of, click and hold then drag diagonally down over the area to the bottom right corner and release the click. That creates a image of just that area of the screen. If you press the Shift>Command>3 keys it created an image of the entire screen without using the mouse.
It is a useful feature for extraction just part of the image on the screen. I use all the time to capture images on web pages.

-- Les B, Oregon

View LesB's profile


2607 posts in 4297 days

#10 posted 02-14-2018 07:36 PM

After looking at it again I think the same process could be accomplished on a router table. It would probably take successive passes with a straight bit to cut out the step to the proper width. Be sure to use hold downs with those long boards to insure control and even cutting.

-- Les B, Oregon

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics