Hip rafter birdsmouth

jlmran · 01-03-2011, 09:56 PM

At least one piece of literature on the market describes a process of cutting a v-notch into the heel cut of a hip rafter birdsmouth. This is performed as an alternative to 'clipping the top plate', in order to allow the hip rafter to rest fully on the corner of the top plate. The literature, however, only descibes the v-notch but doesn't actually detail how the cut is performed.

Can someone describe how you actually cut this v-notch into the heel cut?

I could ask this in a professional forum where the process is perhaps more widely known, but they seem to really harp on DIYers who make entries into that forum. Hopefully one of them will stumble across this. Thanks.

Joe Carola · 01-03-2011, 10:58 PM

Quote:

Originally Posted by jlmran

At least one piece of literature on the market describes a process of cutting a v-notch into the heel cut of a hip rafter birdsmouth. This is performed as an alternative to 'clipping the top plate', in order to allow the hip rafter to rest fully on the corner of the top plate. The literature, however, only descibes the v-notch but doesn't actually detail how the cut is performed.

Can someone describe how you actually cut this v-notch into the heel cut?

I could ask this in a professional forum where the process is perhaps more widely known, but they seem to really harp on DIYers who make entries into that forum. Hopefully one of them will stumble across this. Thanks.

Why do you want a V cut, is this going to be exposed? If not you don't need a V cut.

jlmran · 01-03-2011, 11:11 PM

Joe,

I'm not building anything. I just have this almost insatiable curiosity about various things, and framing is one of them. I came across this while reading the famous book by Holladay and I simply thought to myself, 'how is that cut made'?

Have you used this method?

By the way, there is a thread in the ContractorTalk forum which I think is titled "300 Lurkers?" You may feel compelled to indicate to the author that many of those lurkers are non-professionals who read the forum, but choose not to make entries for fear of harsh, public reprimand.

Thanks for asking...

Joe Carola · 01-03-2011, 11:23 PM

Quote:

Originally Posted by jlmran

Joe,

I'm not building anything. I just have this almost insatiable curiosity about various things, and framing is one of them. I came across this while reading the famous book by Holladay and I simply thought to myself, 'how is that cut made'?

Have you used this method?

I use the V method for exposed hips because it gives you a nice final finished cut. I make it with two saws, one left side blade and the other right side blade because it's easier setting the 45 degree.

The V method isn't needed to cut a non-exposed hip. I can show you a drawing on that if you want to see it.

jlmran · 01-03-2011, 11:29 PM

Joe - I always enjoy drawings, and I especially enjoy your posts. So, yes, I would appreciate a drawing. Thank you.

Joe Carola · 01-03-2011, 11:39 PM

Quote:

Originally Posted by jlmran

Joe - I always enjoy drawings, and I especially enjoy your posts. So, yes, I would appreciate a drawing. Thank you.

This post and drawing below was from a thread at CT few years ago. It's when using a 2x hip (1-1/2"). It shows how to mark the hip length to the outside corner and then adjusting the mark 1/2 the thickness of the hip at the HAP cut line(Height above Plate) so that the hip planes it with the top of the common rafters at the plate-line.

Quote:

Originally Posted by Joe Carola

The Hip runs at 45°. Your hip length goes from the ridge to the outside corner of the top plate. The hip is 1-1/2” wide so half of the hip will sit off the corner on each end of the top plate ¾” each side.

Now the ¾” will have a ¾” run to the top plate. That is the same ¾” run I was talking about coming in from the hip length measurement to mark you HAP cut.

That is because where the outside of the hip hits the plate its ¾” in running at 45°. The height from the top plate and up should be the same as the common rafter HAP cut because that’s where the Common Rafter HAP cut hits.

If you took your hip and spun it around perpendicular to the top plate like the common rafter is, the Hips HAP cut would be in the same spot.

The hip running at 45° creating that little ¾” run to the plate also has a little rise, that rise amount is the “Hip Drop “ amount.

I’ve added more to this picture and drew in a plan view looking down so that you can see the Hip how it sits on the outside corner and creates a small triangle showing you the ¾” run to the plate line.

I hope this helps.

jlmran · 01-03-2011, 11:54 PM

Thanks, Joe.

bluebird5 · 01-23-2011, 10:39 PM

you reading roof cutter secrets?

jlmran · 01-23-2011, 10:53 PM

Yeah, I have it.

bluebird5 · 01-23-2011, 11:14 PM

me too i have worked for a company setting a lot of trusses but have not put up many rafters but i got that book and really enjoyed it i don't think i will ever try his rafter rack cutting method with the chainsaw or beveling valleys when you can just raise the jacks but i like his book it helped me understand a lot

masterofall · 01-24-2011, 06:30 PM

Joe I finally met another builder (figuratively speaking) who uses left and right saws. Most people where I work have side winders and I get critised for having a "heavy" worm drive.
Obvviously if this was a hip that was ment to be seen one would have to stop the plum cut at the seat cut and finish things off with chisels. Care would have to be taken also setting the depth of the opposing angled plum cuts so that a saw kerf is not visable from below.
If anyone would like to see a nice sample of exposed rafter tails google Apchin design corp. In the portfolio look at private residence 2, second picture from the top centre row