how to miter moldings in an old house?

[PeterJeffrey]

Hi, I need some help!

How do you install skirting boards and trims in an old house where no angles are square or walls align with the jambs?
I've tried to cut them on my DeWalt 707 which is evidently starting to get loose, and moreover, it's hopelessly difficult to make miter joints align with each other without any gaps.
Do you have any solution to my problem? What can I do to avoid this issue?

 

[mycke_nu]

It's not easy, I'm struggling with the same issue. Both the house and the lumber are crooked.

Regarding the saw: Make sure the molding lies with the smooth side (backside) against the saw table, otherwise the angle will be off. Also ensure to hold/clamp the piece tightly during cutting, as they tend to shift a bit when cutting at an angle, which leads to a crooked cut.

I sometimes use a bevel gauge when there are large discrepancies, but mostly it's just about cutting, trying, adjusting the saw setting, and cutting again until it fits. Then it’s latex caulking in the gap if it doesn't work out, what can you do?

 

[Blindnit]

Adjust the angle of the saw with cutoff pieces.
Cut, test, cut, test.
And when it's right, make the cut on the real trim.

 

[mycke_nu]

Unfortunately, using scrap pieces doesn't always work when installing baseboards if the floors are wavy.

 

[bonnier]

An alternative to mitering is to use corner blocks, which I think can look quite nice, but maybe not everyone thinks it's a good option.

 

[Ola78]

And another elegant option for floor and ceiling moldings is to cope them. Read more here http://hvilaro.blogspot.se/2008/07/gering-taklist.html?m=1 and here http://callerobertsson.blogspot.se/2009/03/forkroppsligen.html?m=1 Around doors and windows, you can also install so-called plinth blocks, which was common in the past. Then Hultafors has a special tool that is a form of bevel but with a flag that halves the angle, which you then set the saw after.

 

[mycke_nu]

Good links, you need corner blocks, otherwise, I don't know how you would manage with the door frames.

The worst miter problem, I find (if I may continue to hijack the thread), is in outer corners, where you must get the miter right. If both walls slope a bit here and there while the floors are uneven, it becomes tricky.

 

[Ola78]

Good links, you must have base blocks, otherwise I don't know how one would manage with the door frames.

The worst miter problem I experience (if I may continue to hijack the thread) is in outer corners, where you have to get the miter right. If both walls are tilting a bit and the floors are uneven, it gets tricky.

There was a reason for having those base blocks in old houses before, they were rarely as straight and nice as today's new ones. Outer corners, just as you write, are always a hassle. Here is a link to the tool from Hultafors that I wrote about http://www.hultafors.com/sv/produkter/measuring/squares/geringsvinkel-gv/ I have one myself and think it's really great in certain situations.

 

[mycke_nu]

Is there any difference between the miter angle you link to and a regular bevel square? I feel a bit slow..

 

[Blindnit]

Unfortunately, it doesn't always work with leftover pieces when you're installing baseboards if the floors are wavy.

Maybe it's easier to focus on getting the corners perfect and splice the baseboard in the middle between the corners where it's easier to get it right? I'm probably bad at explaining, but the picture is clear in my head

 

[mycke_nu]

Yes, that's correct, it can facilitate, especially if the floors are relatively even.

 

[Stefan Bengtsson]

Is there any difference between the miter angle you link to and a regular bevel gauge? I'm feeling a bit slow..

The "flag" in the angle's joint automatically divides the angle into 2 equal parts, and thus shows how you should set the miter saw.

 

[mycke_nu]

OK, what I need is a three-dimensional angle finder that also takes into account that none of the bases are level and none of the walls are vertical and then translates this into saw settings..

Good thing there's sealant.

 

[Larsa]

The baseboards can be profile-cut instead, which makes it easy to adjust. If you cut the baseboard at 45 degrees, you will then see the profile to cut with a jigsaw. Check this out http://www.byggahus.se/forum/byggmaterial-byggteknik/40654-girning-av-lister.html

When it comes to casing, it's trickier. I usually set one side, then adjust the miter on the top piece. Then remove the side and do the same on the other side, but with a slightly longer top piece. Once the saw is perfectly adjusted for the angle, cut the top piece to the correct length.

The miters in the top piece can also be carved a little with a sharp knife, making it easier to close tightly.

 

[mycke_nu]

Excellent great links above! Thanks, Larsa!

I'll post them here so it's easier for those interested to navigate.

Ceiling moldings: http://hvilaro.blogspot.se/2008/07/gering-taklist.html
Baseboards: http://hvilaro.blogspot.se/2010/02/gering-av-golvsockel.html