?? on butt boards

jklingel · 01-28-2013, 11:14 PM

i made some butt boards as per mae-ling's diagram and have a ?? on them. as i install them, it seems it would be best to have a row of screws along the outer edges of the butt boards (ie, the high ridges) as well as at their centers (the edge of the 'rock). what i think i am seeing (no screws on the bb ridges yet) is that the bb is not as effective with only screws at the edge of the 'rock; there is not a pronounced bending of the 'rock. it seems the second row at the bb ridges would pull the bb flatter to the 'rock at the bb ridges and thus have more bending of the rock. question: is a second row of screws at the bb ridges necessary/useful, or am i just imagining things? also, just an fyi for anyone who has not used them yet but will. i am having to screw a scrap piece of 'rock to the backside of the bb where it passes over wires. despite the wires being centered in a 2x6 wall, elect wires are not steel rods and some jut out near the bb. as i'm using 1 5/8" screws, the tips could hit a wire if no scrap of 'rock were in there. it is not a big deal, just something to be aware of.

joecaption · 01-28-2013, 11:35 PM

Using to long a screw to one thing should be 1-1/4.
The longer ones would be fine for something like 5/8 rock in the ceilings.

jklingel · 01-29-2013, 02:20 AM

joe: i am using 5/8 'rock on the walls and ceiling. i got a bunch of 12 footers for $12/sht instead of $28 in town. military installation surplus. with 1/2" 'rock, i could see using 1 1/4" screws on walls, but even then you are going to have screws sticking through unless you use thick bb's. any idea if two rows of screws per side are needed/suggested for the butt boards?

ToolSeeker · 01-29-2013, 07:19 AM

Your not going to get much flex out of 5/8" just on the end. To be honest have never tried using them with the 5/8 may not not work.

Beepster · 01-29-2013, 09:29 AM

I recently built my own butt boards and used for the first time. I built the board per some post on here and used strips of drywall spacers(?). They are cardboard like strips about 1" wide and 36" long. I used 2 on each side.

What I would recommend when screwing in place is to get your screws close to the end of the drywall on each side so one piece of tape will cover both. Bring them all up snug before you countersink any. One screw will not bend an end but many will. I maybe put them 5-6" apart.

There is no need to put them at the other end of the butt board.

B

jklingel · 01-31-2013, 01:05 AM

beep: your butt boards sound similar to what i've made. i have two, 1" wide strips of #30 felt on each side, and will try some boards w/ 3 layers on each side to compare. i've been checking the gaps as i go, and i am seeing a fairly regular 1/16th inch belly at each butt joint. if that is not enough, it is sure a good start. it still looks like a tad more belly could be achieved with two rows of screws, but from what i am seeing it don't think the second row gets you much, so, pardon the pun, screw it.

12penny · 01-31-2013, 11:55 AM

I just buy them. Open the box and I'm ready to go.

jklingel · 01-31-2013, 12:32 PM

easier, sure, but you can also just hire sheetrockers and make it even easier.

ToolSeeker · 01-31-2013, 08:38 PM

Not only easier but the company where I get mine (Trim-Tex) has done research on how thick they should be to get the max from them without cracking the board, same goes for the width and I thought someone said they use cardboard for the shims. When you tighten anything like that down it is going to collapse enough to be almost ineffective. Just my opinion.

Fix'n it · 01-31-2013, 09:52 PM

Quote:

Originally Posted by ToolSeeker

Not only easier but the company where I get mine (Trim-Tex) has done research on how thick they should be to get the max from them without cracking the board,

same goes for the width and I thought someone said they use cardboard for the shims.

When you tighten anything like that down it is going to collapse enough to be almost ineffective. Just my opinion.

the rock will bend a whole lot more than you think. and WAY more than is needed. been there, done that. but not on purpose

that was me.

you are so incorrect. the cardboard i used could be run over by a truck and not loose its thickness.
in fact, it has worked out perfectly.

jklingel · 01-31-2013, 11:11 PM

i have no experience long-term w/ these yet, but the 5/8 'rock is sure bending, and i suspect (suspect only) that when it gets a bit of moisture from the mud it will stress-relieve and stay put. i have seen guys on youtube wetting 'rock and bending it pretty acutely, and my bro' says he has bent it quite impressively with a similar technique; wet it and wait. i dunno yet, but so far it looks like the home-made boards will work, and i was installing them as cold as -38 F (it was a matter of necessity, not choice). the 'rock did not seem any different than when it is at room temp. when i build the house next summer, i think i'll make boards even wider than the 9 1/4" shown here, just so i can throw in a few more screws and have a slightly less angle to the dip. i know it will be hard to run a 12" knife down them in one pass, but i am not making a living by my speed, so it matters little if it takes longer. we shall have to see how it goes....