Alright gang. Is there such a thing as a steel hardened lag screw.
I’ve been a mcfeelys, grk convert for years.
Just installing a plasma mount into 2×4 doug fir studs.
1/4 X 31/2″ LAG SCREWS.
I picked up some steel ones at the local borg and they were only every so slightly harder than the aluminum jammies I had at home. 2 are in but one just snapped on me…..Holes are predrilled in all.
Just short of lube ;-), does a better 1/4 lag screw exist ?
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Replies
you bought POS lags from China....fasteners are my business. Generic commercial grade fasteners from china are junk. junk steel, junk processes.
one suggestion is to wax or soap the threads. this will reduce the driving torq without effecting the holding capacity. the other is to increase pilot hole size.
Agree with MCF. I bought some ugly looking 1/4" lags from a national chain and they snapped off easily. I threw them out and bought some cleaner, brighter ones at the lumber yard... no problems. The really ragged looking ones with the sloppy, dull galvanizing are not the ones you want. You could probably order some NASA-grade stuff from McMaster-Carr.
Just reading the title I had to open this up. At first I was going to say you're on the wrong board but maybe not.
Flying from the seat of my pants here....what about using Timber-Loks for lags? They drive like the catz azz and hold many a deck together - they should hold your plasma bracket to the wall.
-Norm
"Alright gang. Is there such a thing as a steel hardened lag screw. "
Yes, and they are not as easy to find as they used to be. Specs may call for these specialty fasteners by a number 3, 4 or 5 depending and they have to be special ordered. They're used mostly in steel construction. It's a different strength of steel is all and you won't find these at your local hardware or box stores. Time was when a well stocked hardware would carry these, but I haven't seen them in a while. I used some on a job about 5 years ago but that was the last time.
Second VTNorm here- Timberloks are a good choice for that size. They've got them in 1/4 x 4", not sure about 3 1/2". They do have 3/8" x 3 5/8" though. GRK's RSS screws are also good in that size range.
I like the thicker coating that Timberloks have, and the hex head it has. A fair number of the longer timberloks aren't straight though. I don't know if that affects their strength, but I've thrown a couple away because they wouldn't drive right.
zak
"When we build, let us think that we build forever. Let it not be for present delight nor for present use alone." --John Ruskin
"so it goes"
The hardened lag screws are Grade 5 and not common "over the counter" stock. Standard lags (Grade 2) may have 307 or 307A stamped on the head. The Timberlok screws are advertised to be harder steel than your common Grade 2/307. The coating on the Timberloks add a bit of lubrication. I would agree with a previous post that the Timberlok screws might be your best bet.
Simpson Strongtie makes 1/4" structural screws in 1-1/2", 3", 4", and 6" (maybe more sizes). They are ok, but when 3/16" pilot holes are drilled in doug fir, about 1 in 25 break where the threads meet the full diameter shank before seating into the wood.
Timberlocks don't break. At least I've never had one break in the 6 years I've used 'em. The steel and heat treating are better than the Simpson screws.
Beer was created so carpenters wouldn't rule the world.