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Drawboring #31092 10/01/13 01:55 PM
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astc Offline OP
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Hi. I am hoping someone can comment on drawboring. I am designing and building my first post and beam structure, a 14x10 woodshed. Should I plan on drawboring every mortise and tenon joint? Is there and order which you should do it? For instance can you drawbore the braces as well as the plates and crossbeams or would you do one and not the other? Also, what pegs should be used when drawboring? Tapered, chamfered, octagonal? And what pegs should you use when not drawboring. Thank you for your help.

Re: Drawboring [Re: astc] #31095 10/01/13 02:30 PM
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Jay White Cloud Offline
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Hi Astc,

Some of this is specific to the type of timber framing you are doing. I would also note, within the realm of the craft, there is much diversity. You very well may get a number of variable answers to this question.

Quote:
Should I plan on drawboring every mortise and tenon joint?


Short tenons, like on braces do not require draw boring and in general, braces only work in compression and don't even need to be pegged if the frame is cut well. Braces do respond to wedging in some styles.



Quote:
Is there and order which you should do it?

This could depend on style and system of raising so is hard to give a definitive answer.

Quote:
For instance can you drawbore the braces as well as the plates and crossbeams or would you do one and not the other?


You do not draw bore braces, there is not enough relish in the tenon.

Quote:
Also, what pegs should be used when drawboring?

Dry hard wood is typical (and probably the best) but there is plenty of heart pine, and other conifer as well found in vintage frames and other styles.

Tapered, chamfered, octagonal?

Tapered is about the only "yes" to this answer but the rest is subjective.

Quote:
And what pegs should you use when not drawboring.
I don't think I am understanding this question? The pegs down change whether you draw bore or not.

Hope this helped.

Re: Drawboring [Re: Jay White Cloud] #31098 10/01/13 05:05 PM
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TIMBEAL Offline
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I must point out that Jay often comments as if his answers are the end and final result. Go right ahead and draw bore you brace stock or not. Sure it can be assembled without pegging but I like pegged bracing, if for nothing else it aids in assembling. I also have mostly switched over to assembling the frame work and pricking the tenons, pulling the joinery apart and drawboring from there. Wonderful not to have fouled up peg holes.

Re: Drawboring [Re: TIMBEAL] #31100 10/01/13 06:09 PM
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Roger Nair Offline
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There are three basic methods of drawboring that I am aware of:

1. Layout on the horses and bore as part of joint cutting process. Pros are efficiency of effort. Cons are the absolute lack of fault tolerance.

2. Tim's method of assemble on the deck, prick offset center, disassemble, drill and reassemble and drive pegs. Pros are easy control of frame dimensions with fault tolerance. Cons are related to efficiency ideals.

3. Point to the joint drilling. The mortised member is predrilled, The frame is assembled and strapped tight, the bore is drilled with slope. Wild card method, not consistent for me to endorse.

Re: Drawboring [Re: Roger Nair] #31101 10/01/13 06:34 PM
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Jay White Cloud Offline
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Roger, great concise break down, I have to work on that for speed.

Tim, I am sorry if I offended you in someway, I though my entry was rather neutral in general. My answers are not the end and final result of anything, just the reflection of 35 years of studying, restoring and cutting frames. Considering what I do for a living though, for the duration I have done it, and the amount of failed pegged braces I have seen, my entry was germane, appropriate and true. It was not subjective at all.

I actually though of you last month and some of our conversation we have had around pegs. One of the Amish crews I work with are seeing a number of frames in certain areas of Ohio that use a smaller peg for braces, with keen understanding (circa date after 1830) that peg bracing came about as a facilitation method for raising, nothing more. On rare occasion, we have found barns (one house so far) that used a large metal nail (spike) to serve this purpose. Minnesota, Michigan and Wisconsin vintage barns thus fare studied and taken down, do not have pegged braces and some are, what appears to be wedges added later.

Regards,

jay

Re: Drawboring [Re: Jay White Cloud] #31103 10/01/13 09:43 PM
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TIMBEAL Offline
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Not offended at all Jay. I actually chuckled a little as I sent that one off. It could just be me and the way I read post.

I am moving to almost full scribe in my shop and as such I find pricking the joinery a simple step to make, it all comes together without any worries. What I am finding after years of square rule is scribing is not more time consuming if weighing the tidy results it yields, it has many benefits.

I may try snap line square rule some time.

Unpegged bracing is far and few between in my neck of the woods, I can recall only one barn and that was in western Maine near the border of New Hampshire. Most barns here are full 2" tenon 3 to 4 inches deep with a softwood 1" peg. I use 3/4" hardwood in most joints unless they are doing some major work.

Re: Drawboring [Re: TIMBEAL] #31104 10/01/13 11:08 PM
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Jay White Cloud Offline
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Hi Tim,

I feel much better now. Though we debate sometimes I really respect your views and opinions. I always learn something because you challenge concepts really well and ask great follow up questions to the information others share.

I had a feeling when you said you are "pricking" to layout your draw boars that you are using scribe rule. As such that is the way it is (was) done. I would go as fare to say, historically, "pricking" is "the" method for draw boring, and the latter method of doing it all by measured off set is about the same age as "edge rule" (~300 years at the most.)

I also agree, since the onset of the industrial age, when "edge rule," came into its heyday, that folks in our craft of Timberwrights forgot the pleasures and benefits of "scribe rule."
I also agree, after more study and examination that I do not believe it is that much slower when all things are considered. In general application it may be, but the flexibility of design, broader range of material use and choice and uniqueness of frames using this method out way the draw backs.

I know this could be seen as subjective, but draw boring, and line rule are the roots of this craft and I like practicing them. Edge rule is nice, but I really wish our younger Wrights would star to embrace the soul of this craft and let the influences of the "industrial age" go.

If you ever find a frame with un-pegged braces in Maine please let me know, as that would be rare for that part (as is most) of New England. Norther and Eastern European influence is my current theory about un-pegged braces that are found in this country.

Last edited by Jay White Cloud; 10/01/13 11:21 PM.
Re: Drawboring [Re: Jay White Cloud] #31106 10/02/13 12:30 AM
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Dave Shepard Offline
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I drawbore all joints. Pegs may not be required after raising, but it is nice to pull everything together before raising an assembly.

Tim, I've been working on two Dutch barns for the last 3 1/2 years, both scribe rule. When I use square rule now, it feels a little odd. I want to use scribe as much as possible going forward. I think working with natural forms, like crucks and curved stuff will help justify using scribe rule. I've heard some people say that scribe is about 1/3 more time to cut a frame than square rule. I suppose it is if you don't test fit the square rule frame, which I don't, but I often hear of people test fitting square rule assemblies. Might as well scribe them, unless you don't have the room.


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Re: Drawboring [Re: Dave Shepard] #31108 10/02/13 01:12 AM
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TIMBEAL Offline
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When I do edge square rule I bore peg holes with out fitting. On the scribe side I am enjoying not cutting all the reductions and housings. I only put such things in where loads should require more bearing surfaces, and then usually a haunch. I can get away with smaller dimensioned timber,too, that equals lighter sticks.

If I come across unpegged brace framiing I will let you know, Jay.

Re: Drawboring [Re: TIMBEAL] #31111 10/02/13 07:27 PM
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D L Bahler Offline
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We have had this discussion before,
It is true that in theory oblique bracing works only in compression. Rudimentary design principles tell the logical mind that this should always be the case, so in other words examining a frame on paper will lead us to believe that a brace can act possibly in one direction only.

However, I have observed exceptions to this rule.

Case in point, my area in Indiana could be called the wind capital of the world. We get terrible winds during summer squalls frequently in excess of 60 mph with heavy rains carried on these winds -barn busters.

We also get these funny lookin clouds that are called tornadoes.

Both of these can cause frames to act in ways that are, well, unexpected.

Here, pegged braces can be the difference between success and failure during an instant-loading scenario during a severe storm. Central Indiana barn builders of the 19th century went to great lengths to built with this in mind. It is not unusual to see reinforcement in our barns that would be unnecessary in many other places.

I'd love to survey our barns in this region, if someone would pay me for it!

Now as for the OP, when it comes to drawboring a lot is left to personal preference. I can't really answer that any better than has already been stated by others, except to say that there is no concrete rule stating you HAVE to do it one way or the other, or you HAVE to draw all pegs, etc.


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