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andrewmct
05-08-2013, 05:13 PM
Hi. I am going backwards in my project now, as I need to move out of the carport to the side of my house. I have been building a 10x20 bow roof shed and I'm about half way building 16 bows. I have noticed that there is quite a bit of variation in shape even though all of the bows are coming out of the same jig. I'm sure this has to do with how springy each board is. Does this matter? Should I make a raft of bows and choose the best ones? Is this normal? Are there any tricks to building them all the same? Thank you for the replies.

Andrew

BBSebens
05-08-2013, 10:25 PM
I assume the shed will have a ridge beam? If you use a fairly stout one, it ought to bring them close enough into line that it won't muck up the covering. Doubles as a handy pick point for lifting larger components. A bit of cross strapping might help too.

Again, assuming, you are using fairly cheap materials for the bows? its not that surprising that they are somewhat different. I wouldn't sweat it on a temporary (right?) building.

gilberj
05-08-2013, 11:57 PM
I two words...probably not......the builders-poly is pretty easy to adjust to fit. the only concern is having enough head room for the job being done...

Cogeniac
05-09-2013, 12:26 AM
I wouldn't sweat it on a temporary (right?) building.


Famous last words...:p

S

knottyBuoyz
05-09-2013, 05:22 AM
I don't think I had two that you could call a 'pair' Andrew. Like the other guy said, 'don't sweat it'.

If you look on the top of the pile you'll see how much some of mine differed.

http://i237.photobucket.com/albums/ff166/KnottyBuoyz/KBIII/IMG_1927.jpg

Diagonal bracing is very important to the structure.

Good Luck

Rick

PS. More pics here

http://s237.photobucket.com/user/KnottyBuoyz/library/KBIII?sort=3&page=17

moTthediesel
05-09-2013, 06:21 AM
Rick

PS. More pics here

http://s237.photobucket.com/user/KnottyBuoyz/library/KBIII?sort=3&page=17

That's a nice bow shed Rick -- but that blue, ouch! -- I've got a headache from just looking at the pictures..... Maybe it doesn't effect everyone the same way, but even when I shrink wrap boats with blue plastic, I can't stand going under the covers for more than a couple of minutes. I usually use the blue here beacause I think it warms up and sheds snow a little better, but if I was going to work under it, I'd make it white.

Tom

Figment
05-09-2013, 07:45 AM
Ditto some of the above; the longitudinals and diagonals will bring things well-enough into alignment.

andrewmct
05-09-2013, 05:42 PM
Thanks for the replies. Mine are similar to the ones in the photos, so I won't sweat it. I had given some thought to a 20' long portable garage ( a good one for about $1000) and decided to go with building this shed. I don't know if everyone else has experienced this but, man, is my shed turning out to be a lot of work! I think next time I might buy the shed and build the boat. Oh well, it will be nice when it's done.

RevWhop
05-09-2013, 06:08 PM
What is the spacing on your arches? I am assembling some bows for one also but not sure of the spacing. It will be taken down once hull is finished. Hopefully a month or so.

Figment
05-09-2013, 06:29 PM
I built one at 24" spacing and one at 30" spacing. For coastal CT snow loads, 24 was overkill and 30 was good. 36 will work, I think, but the cover material will need replacement sooner.

And yes, the shed is more work than you expect, but far better than the purchased-whole things I assure you.

gilberj
05-09-2013, 08:50 PM
We had a bow shed for a building job in a heavy snow load area. We recovered the plastic 3 times in almost 6 years... but the show and rain stayed outside.... it never failed.....I don't remember the spacing of the frames, guessing about 30 inches.

kc8pql
05-10-2013, 03:03 PM
I used 48" spacing on mine. 24' X 44' X 19' high inside. It lasted just fine for the 10 years I needed it. Snow just slides right off, and the building flexes to handle high winds.
If you plan to heat it in the winter, put plastic on the inside too.

http://xa.yimg.com/kq/groups/13765734/hr/1356146667/name/n_a

http://xa.yimg.com/kq/groups/13765734/sn/1432410890/name/n_a

http://i6.tinypic.com/1zbvs6v.jpg

Tangusso
05-10-2013, 03:26 PM
I used diagonal bracing attached to each bow to pull them into shape when I added the legs. It worked well to remove most of the variation in the curves. I used heavy weight greenhouse fil and the associated attaching hardware to assemble the plastic to the frame. This sheeting has a UV filter to minimize damage to brightwork, while transmitting 80 +% of the visible light.

http://forum.woodenboat.com/showthread.php?158657-Restoration-of-a-1935-Richardson-Cruisabout&highlight=rstoring+a+1935+richardson

scottmacc
05-11-2013, 12:45 PM
Mine is 20" x 40". Likewise, few of my bows we're exactly alike. Since I couldn't find 20" long 1"x3"s, I re-sawed and ripped 2" x 10"s to get what I needed. They were pretty wet also which made cutting hard but bending easy. Mine are spaced 36". For covering, I used white shrink-wrap, and since I could only find it in a roll too large, I covered it twice. It's very sturdy and has withstood several heavy snows up here in Maine. http://i410.photobucket.com/albums/pp185/scottmacc/100_3113.jpg