sobon shed post question

[Alexis]

hello,

i am currently doing the layout for a post of a sobon shed. I am marking the tie beam mortise into the post. My post seems to differ quite a bit from the one illustrated in the picture and the drawing of the book. From the top of the tie beam mortise to the top shoulder of my post, there is only 5 inch. every measure is good, the mortise top is 8 ft from the bottom of the sill, so 7ft 4 inch from the bottom shoulder of my post ( because the sill is 8 inch deep)

In the photo and drawing, it seems like he has a good feet on top of the mortise before the shoulder

thanks

Alexis

[Raphael]

the mortise top is 8 ft from the bottom of the sill

Did you mean to say, 8 ft from the top of the sill?
I haven't got the book here (I'm at work) but if your question hasn't been answered by tomorrow afternoon I'll look for it.

[Alexis]

nope, on page 100, the drawing show that it's 8ft from the bottom of the sill to the top of the mortise so to calculate the mortise hight, I removed 8inch so it's 7ft 4inch from the bottom shoulder to the top of the mortise

Alexis

[moonhill]

Alexis, how long is your post stock?  10 feet is what Sobon is using.   

Tim

[Alexis]

I bough 10ft, like in the book. I don't have the book at work with me, but from what i remember, the post is 8ft 9 inch shoulder to shoulder, 2 inch tenon on the bottom and 5 inch on the top.

[Jim_Rogers]

First of all if you're doing the shed in the book, and not creating one larger than that, you can change the housings depth from 1" to 1/2". There is no need for 1" deep housing, this will save you lots of work.

Also, as mentioned the posts rough stock is 10' (120") long. If you subtract the 8" for the sill then the post is now 9'4"(112"). If you then subtract 7 1/2" for the plate the length is 8'7 1/2"(104 1/2") or for the post the shoulder to shoulder measurement.

The tie beam is 8' (96") above the bottom of the sill, subtract 8" for the sill and it's 7'4" (88") from the top of the sill to the top of the tie, subtract the 8" for the tie and the top of sill to bottom of tie is 6'8"(80").

The distance from the top of the tie to the bottom of the plate is 16", and to the top of the plate is 24" with the difference being the plate thickness of 8".

Hope that helps...

Jim Rogers

[Alexis]

!"/$%?&*(!!!!
I found my mistake, I burnt a foot for the shoulder to shoulder lenght but forgot to add it to my measure! So it was 7ft 9inch shoulder to shoulder instead of 8ft 9 inch!

thanks for your help

Alexis

[Jim_Rogers]

When we measure and mark our drawings we usually measure and mark them using inches only as it's easier to add and subtract in our heads.

For example, if you have a post that's 120" long and you're going to layout a 32" brace layout it's easier to just subtract 32" from 120" then trying to do it all using feet and inches.

When we layout we usually burn 10" as it's easier to do the math.

So when we have someone hold the tape end we have them hold it at 10" and then we add 10" to the end. (if you're working alone, have a clamp handy and use the clamp to hold the tape for you. But then check as mentioned below).

To insure we have done it correctly, once the mark has been made we then put the actual end of the tape on the beginning point and then check the new mark to see if it is truly at the correct spot. This is where we are "measuring twice" and then only cutting once......

Also, if you're laying out a lot of timbers and you make a mistake on one, the 10" mistake shows up a lot quicker then say a 1" mistake.....

Jim Rogers

[moonhill]

I believe this is the second admitted cutting mistake in a few months, both from the same method.  I have just about given up the "burning a foot" or "10 inches" method.  I will find a common number relating to the job at hand or create one at 24".   In Alexis's example I would hold 8" on the bottom shoulder of the post, zero would be the bottom of the sill, 4'& 5' the top of the girts, 8' the top of the tie beam, 10' the top of the plate then back 7"(or 7-1/2") for the shoulder.   Base the brace measurement from the tie beam mortice and the top shoulder for the top plate brace, using the full 36".  Jack did a nice job with the numbers on this frame.

The next step is the fix?

Tim 

[Raphael]

The error I've managed to perfect recently is the 1/2" error from setting the blade of my square at zero and adding 2" to the inside scale instead of 1.5".   :

[Jim_Rogers]

I've seen Jack check timbers using the layout method you have described.

I sometime do that as well....

Jim Rogers