Re:Pavilion Architecture Questions
- M'Lord,Why pressure treat? Especially for the cross member. Flying termites? It's way heavier but not way stronger.Why 4x4? A 4x4 is only twice as strong as a 2x4. A 2x8 weighs the same but is 4 times as strong in relation to downward pressure. The side to side stresses will presumably be balanced by the two opposing sides of the tent.If one wanted to be really clever, one could correct for the inevitable sag at the splice by a tensioned cable on the bottom of the beam. (Just cause you could.)
Craig RobertLord Craig Robert le Luthier de Pierrepont OVO CAR
Apprentice to Dame Alysea of Ashley
Posted by: "Thomas E Handwerker" ghandwerker@... ghandwerker
Fri Feb 2, 2007 6:29 am (PST)Greetins all,
I have a question reguarding the architectural strength of wood. I am attempting to span a 24ft length for a Saxon A frame pavilion. I am thinking of doing this by using 10ft preassure treated 4x4s for the uprights at each end of the tent. Then I am planning on using two preasure treated 12ft 4x4s as the cross beam by connecting them end to end with a 3ft 1/4inch thich steel cuff bolted in place. Do you guys think that the steal cuff will hold the 4X4s, or am I building a death trap?
Finding fabulous fares is fun.
Let Yahoo! FareChase search your favorite travel sites to find flight and hotel bargains.
- As an Architect used to dealing in spans and loads I may be able to give you a little help :-), I don't recommend using treaded 4 x 4's. They will twist on you like a pretzel. I'm yet to see one remain straight when used horizontal. Their strength comes from vertical support. 24' is a hell of a span even it we go as low as a 4 pound roof load (very low weight compare to a normal structure) If I had the actual size of the tent I can figure out a weight load on the ridge beam, which is what you are making. Instead I would use yellow pine nominal lumber and lap join the two pieces, use a steel sleeve like you planned and bolt it using 1/2" bolts. Even with that I would not sleep under it. I would put a center post. With the low weight of a tent roof I would not recommend anything less than 2 x 10's.Another important point: How are you attaching the end posts to the ridge beam? The structure is only as good as the joint of the supports. Email me with more information and I will be able to figure out the loads.For the rest of the group, if you guys need a plan drawn for one of you projects I would not mind drawing it in AutoCad for you. I have gotten some good information out of the group and it is a small way to help out.Pepin de Bourgogne(Joe)
Sent: Fri, 2 Feb 2007 9:29 AM
Subject: [MedievalSawdust] Pavilion Architecture Questions
Greetins all,I have a question reguarding the architectural strength of wood. I am attempting to span a 24ft length for a Saxon A frame pavilion. I am thinking of doing this by using 10ft preassure treated 4x4s for the uprights at each end of the tent. Then I am planning on using two preasure treated 12ft 4x4s as the cross beam by connecting them end to end with a 3ft 1/4inch thich steel cuff bolted in place. Do you guys think that the steal cuff will hold the 4X4s, or am I building a death trap?Thanks!VolkahardHouse Hedgehog
Everyone is raving about the all-new Yahoo! Mail beta.
- Are you talking lag screws or through bolts? I would not recomend any
screws in the joint section. They would wear out after 5-6 take downs.
Through bolts with fender washers on both sides are better though you have
to make sure the head and nut ends do not touch canvas.
< I'd use lag bolts >
- Greetings unto the group!
My name is Malaki Dracwin and I am new to this group. Please forgive
this rather lengthy first post.
I haven't yet gotten to read all of the past posts, but this pavilion
pole issue is one that I have dealt with before. Too often these
things are over-engeneered. In my experience, lighter is better. When
my wife and I were first married we purchased a double bell wedge
from Panther. It has only a 5' ridgepole, but the two poles that went
from the ends of the ridge, although only 1.25" in diameter, took up
a LOT of floor space. To remedy this I built a new ridgepole of
mahogany (light-weight and strong) and set it so that one of its
rounded corners (square cross section) fit into the top of the ridge.
I then drilled four holes for upright poles that matched the angle of
the sides of the tent, which I reinforced by gluing in steel tubing
within which the all thread of the poles would slide, preventing
undue wear and tear. The pole set-up resembled the frame for a swing
set. This works especially well in the high winds of Ansteorra.
A few years later we purchased a large pavilion from Tent Masters,
measuring about 10' x 20' at its base. With the ridge pole (2" x 2" x
8') set in on top of two 1.25" diameter poles, the pavilion stood
well enough but we once again found ourselves with the pole problem
in the most inconvenient of places.
While studying architecture I became fascinated with the concept of
the compression ring. Such a ring is used in Mongolian gers (yurts)
in the form of a very long, woven belt that girdles the top of the
lattice, keeping the center ring and rafter poles from pushing it
outwards. I noticed that our large pavilion already had a compression
ring of sorts in the guise of the drip flap, which was reinforced
with heavy, woven cord. This sparked an idea.
I made a ridgepole of laminated mahogany (2" x 2") with the two holes
for the all thread of the vertical poles. These were specifically for
pitching the tent. The ends of the ridgepole had a horizontal double
hole in each end. Into these double holes went a piece of 1/4" steel
wire bent into the shape of a Y, the base being doubled and therefore
would keep the Y from twisting in the hole. Once the pavilion was
pitched (with the Y's in place) a rafter pole would be put into
place. Each rafter pole had a 1/4" hole in the top end and a screw
eye in the bottom end. Because my parameter poles are all 1.25" dowel
rod (as straight of grain as possible) with 1/4" all-thread glued
into the top end for the rope, all one had to do was to stab the arm
of the Y into the hole of the rafter pole, remove the rope from that
corresponding corner pole, slip the screw eye onto the all thread and
replace the rope, making sure that the drip flap compression ring was
well seated over the pole (the edges of the poll ends should be
rounded off to prevent wear on the canvas). Do this to all four
corners and you have a pavilion with no center poles (a rather
magical feeling when one walks in).
I realize that this sounds pretty flimsy, but I never had a problem
with it coming down on my head, even during near-tornadic weather. We
have even had a slight snowfall on the tent without any form of
mishap. Admittedly it is a bit of fun to set up, but it works.
Good luck with yours!