Easy Cure for Miter Joint "Gaposis"





Introduction: Easy Cure for Miter Joint "Gaposis"

This miter joint is close to fitting, but it has a slight gap on the inside of the corner. Few things diminish a good wood project like miters with visible gaps. It is a great feeling to make a picture frame or install molding and have tight, clean miters.

Step 1: A Quick and Easy Solution to Miter Joint Gaps

Firmly clamp the members of the joint at the angle needed, in this case a 90 degree corner. Gently run a fine tooth saw down the joint between the two pieces. A back saw or a dovetail saw works perfectly. When finished, slide the members of the joint together and fasten in place with glue or nails.

Step 2: The Final Fit

This is the same joint after running a dovetail saw through it by hand. The fit is tight. The look is perfect and very professional.

If your gap is large, bring the two members of the joint together and run the saw between them again. In most cases, you will not create a fit problem for the other joints by removing a tiny bit more material at this corner.

If you are working at installing molding in a house, be aware that the corners on many walls will often be a bit greater or lesser than a perfect 90 degrees. Take a couple of pieces of 1 x 2 two or three feet long that are very straight. Fasten them together at one of their ends with a bolt and wing nut. Use this as an angle finder to check the actual angles of your corners. Measure the opening in the angle finder with a protractor. Adjust your miter saw accordingly. If there are still inaccuracies in your cuts, you will have less material to remove with a dovetail saw in order to get rid of any gapping.

This idea originally came from a high school woodworking textbook published in 1910. I believe it was called "Woodworking for Secondary Schools."



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This is incredible, and what with the timing your advice has to be a God-Send. I have alot of... erm...wonky joints to correct.

I will soon be putting baseboard into a three bedroom house. I saw a Stanley Angle Divider someplace and recently did an Instructsble on how to make one. Still, some care needs to be exercised when transferring angles to a bevel finder and then to the saw. That Instructsble may be helpful to you, too.

thanks for the info , just used your suggestions and they made a world of difference

Thanks. I wish it had been my original idea. I am glad it helped you.

Great tip! I've often ran into problems installing base boards because of the irregular corners that were over filled with drywall mud, or the factory taper used to bed the tape. I would just cut the miter less than a 45 degree so that the outside edge of the cut is "tight" and the inside edge only needs a little caulk at the top corner.

Another problem is that the drywall board doesn't go all the way to the floor, and the base board sometimes "rocks" into the gap at the bottom, making your miter really hard to stay tight. If you find the bottom of the miter "opening" up, drive a drywall screw into the bottom plate, just under the drywall, to give your base board a backing in witch to rest.

I am sorry I missed your comment. You have good solutions to common problems. Unfortunately, not every corner in a house is exactly 90 degrees. I had a little adjustable miter box and our neighbor needed trim in a couple of rooms for a social occasion. I think not one of the room and doorway corners was exactly 90 degrees. I used a bevel finder with a locking nut to check the corners and adjust the miter box. It took a little extra effort, but the results were good.

will use this to beautify the gap on my porch railing. thanks

Thank you. I wish the idea had been original with me!

Holly mackerel !…

Why didn't I think of it ???…

The simplest ideas are always the more brilliant !…

I sure wish it were an original idea with me. I shamelessly stole it from a book. Since I have run into other people who learned it other places.