Urgent help needed.

[Asennad]

Hi I am building a dollhouse for my 3 yr old niece for Christmas. I am using plans I found on the internet a couple of years ago. The roof has small two gables but the instructions do not give compound cut angles and relies on trim to cover the butt joints. As I am not using trim just paint I need to make water tight joints where the gables meet. In the future I will add trim.

The center roof angle is 90 degrees and the two smaller gables are 67 degrees. Where the center roof meets the small gables the plans specify a 51 degree flat cut without any bevel. I need to know what bevel angle I need. Thanks.

[Scottydont]

Oh...LORING!

[Tom Miller]

Maybe I'm missing something, but why does there need to be a bevel there? I would think a flat cut on the gable roof would be butting up to the flat surface of the main roof, no? I guess I don't see why this joint would be mitered.

Regards,
Tom

[cgallery]

+1 what Tom says. No bevel necessary.

[JR]

The compound cut must be at 78.48*.

Proof:
If the gable roof were horizontal (0*), the compound cut would be at 45*.
If the gable roof were vertical (90*), the compund cut would be at 90*.
The answer is therefore between 45* to 90*, or a total of 45*, when the gable angle is between 0* and 90*.
67*, the angle of the gable roof, is 74.4% of 90*,
therefore the compound angle must (74.4% of 45*)+45, or 78.48*.

I guess you actually set the angle at 90-78.48=11.52*

Or maybe it's a different answer, using logic which I don't understand, which frequently happens. Whatever.

JR

[backpacker85]

If you're talking about where the "sheathing" will meet in the valley, as long as the roof ridges are perpendicular, there should be no bevel required.

[LCHIEN]

I, too, don't understand why a bevel is needed or wanted. Won't be obvious either way.

[backpacker85]

.....maybe back cut a few degrees just to make sure the exposed edge butts tight, but other than that.......thicker paint

[Asennad]

The joint absolutely needed a bevel cut.

As I had already joined the two pieces that formed each gable I taped some sandpaper to a work bench and hand sanded the bevel into the piece. Worked out well.

[backpacker85]

Sorry....the more I thought about it, you and JR were absolutely correct.

Guess I never had to bevel my plywood in a valley like that, but I sure have had to bevel a few rafters that hit the main roof in the same fashion.