Sometimes finding the exact trim to replace missing or damaged trim is not possible. Especially for older styles or specialty trims. Fortunately, there is an EASY way to create an EXACT copy of this trim to replace it!


How to duplicate trim that is missing or damaged
When we first moved into our new house, we had a section of trim in the living room that was missing. What was left of the trim was jagged and damaged. We searched and searched for the same trim EVERYWHERE. But had no luck since this trim is very unique. My husband suggested we remove all the trim around the door since this trim is just decretive, but I loved the old charm it gave our house.
Fortunately, the idea for replacing the missing trim finally came to me! I can create a mold of the trim that isn’t damaged, and use that to create an exact section of the same trim. I have done this technique on furniture, so why not use it on our homes interior?!
Supplies
- Easy Silicone Molding Putty kit
- All purpose bondo
- putty knife
- variety of sandpaper
1. Make silicone mold of undamaged trim
The first step in this process is to create a silicone mold of the undamaged trim. Later, this mold can be used to create the exact same trim that it was molded to. I like using this Easy Silicone Molding Putty kit because this product is great at molding even the smallest details plus it is reusable if you ever need to create it again in the future.
To create the mold, simply mix together a small portion of the dark purple putty with the same amount of the white putty. You only need a small amount to create a mold, I usually start out with a section alittle smaller than a golf ball. Mix the purple and white putty together until you see no more white veining in the putty. By mixing these two colors, you are activating the product and it will begin to harden slowly as you work. Smush the putty onto a section of undamaged trim. Push the product all around the section of trim to make sure you mold all the details. Remember to work quickly because the product will start to harden after 5 minutes!
After you have molded the undamaged trim, let the silicone putty sit for 25 minutes to fully harden. Don’t worry it is made of silicone so it will remove from the wall very easily! After waiting ~25 minutes, you can peal the mold off the trim and you will see it created an exact copy of it! Pretty cool- huh?!

2. Fill mold with Bondo
Once you have create a mold of the undamaged trim, you can use this mold to create a section of trim to replace what is missing. Simply fill the mold in with all purpose Bondo. I like to use all purpose bondo on anything I want to make sure it very durable. One of the things I love about Bondo is it dries VERY hard. This is the perfect product for this application because Bondo is as durable as wood (if not stronger!).
To use bondo, simply scoop out a portion of the product from the large can. Take out about as much as you think you will need to fill in the mold. Then add a small pea-sized amount of the creamer harden to it and mix. This is a very similar process as with the silicone putty. With Bondo, you have about a 5 minute working time (less if you added more cream hardener) so again work quickly. I used a putty knife to scoop the Bondo from a paper plate or scrap section of cardboard and placed it in the mold. I tried my best to make sure I didn’t over load the Bondo all around the side and kept it flush with the mold so there would be less sanding I’d have to do later.

3. Place mold on missing trim
After you have filled your silicone mold with Bondo, simply place it on the surface that you are missing trim. I used tape to hold my mold up since it was on a vertical surface.

Then simply let the mold harden before removing the mold. The product label states that it will harden in 15 minutes and be completely sand-able. But when you are using a lot of Bondo, I have found its better to wait 45 minutes to 1 hour before removing the mold to ensure its mostly set up. Its ok if its not 100% harden when the mold is removed, but you do want it to be hard enough to attach to the surface on its one at this point. Make sure it is fully before moving onto the next step.
4. Sand out imperfections
The last and final step of this process is to sand out the inevitable imperfects to make a seamless transition between the undamaged and damaged/missing trim. Since I was creating a section of trim that was longer than my mold, I needed to repeat steps 1-3 over and over until I reached the floor. Therefore, most of my sanding and detail work went it to smoothing out the multiple sections of Bondo. If you are just fixing a small area, you will have a lot less sanding to do.
To make sure I got the best, smoothest look possible- I kept switching between a variety of sand paper grits. For example, when I had a large section to smooth out, I used a 80 grit sand paper to remove a lot of material quickly. But when I was just smoothing out lumps and bumps, I found 120 grit was best. Then finally, I went in with a 220 (or higher) just to further smooth everything out. Take your time here, this is what makes it nearly impossible to notice the difference between the original and repaired trim. After I was finished sanding, I just vacuumed up the Bondo mess left behind and gave the trim a quick coat or two of paint! Now it looks so much better, and I am so glad I thought to do this instead of removing this original one of a kind trim!


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