Raised on the Erie Lackawanna Mainline- Supt. of the Black River Transfer & Terminal R.R.
Capt. Grimek wrote:I started with T nuts and one and a half inch bolts and am trying to decide how much to let them protrude on carpet and padding.I don't anticipate much house settling, etc. Would an 1/8"-1/4" of thread(s) adjustment be plenty on average?I figure we don't want much more than the head of the bolt and maybe 2-3 theads protruding below the wood 2X4s. Otherwise they look like stilts! (like my 1and 1/2" bolts do so far...)
I'm an NTRAK'er on nights and weekends. You'll need more than 1/8 -1/4 adjustment for settling into carpet and pad. Readjustment will also be needed as the settling will take awhile.
Daytime, I'm in the carpet business.
Funny this topic came up today. I just came up from my cellar after installing 3/8" X 2.5" T Nuts and carridge bolts into 6 4"x4" legs for a new work bench. Using 3/4" MDF and 3/16 tempered hardboard for the top. I just used a square with a 45 degree angle on it to center a hole in a jig out of a scrap piece of 4x4 2" thick. Drilled a 3/8" hole and clamped it temp. to the bottom of the leg. Drilled with a drill press so it's nice and plumb with leg. All I did was use the 3/8 bit to widen the hole a little for the barrel of the T Nut with my hand drill, battery powered of course. The carridge bolt turn freely with fingers after installed. Concrete floors are notorious for having dips and high spots, never saw a level one. Even the one finished with a whirly bird, they do come out like glass with the machine tho.
Asked the guy at HD if they had T Nuts, he said he been in the hardware bisiness for 45 years "Never heard of em", I took one out of my pocket, "Never saw one of those", he said???
WWW.boltdepot.com if you live in the NorthEast. They got em to me overnite UPS ground from Brockton MA.
Jules
www.mcmaster.com
Goto catalog page 3103 or just type "elevator bolts" in the search form on the left side of the page.
Capt. Grimek wrote:What is the average length of your layout benchwork's height adjusting leg bolts?I started with T nuts and one and a half inch bolts and am trying to decide how much to let them protrude on carpet and padding.I don't anticipate much house settling, etc. Would an 1/8"-1/4" of thread(s) adjustment be plenty on average?I figure we don't want much more than the head of the bolt and maybe 2-3 theads protruding below the wood 2X4s. Otherwise they look like stilts! (like my 1and 1/2" bolts do so far...)What have you used/allowed to protrude below your wooden legs? The Wescott bench building book doesn't have any specific guidance about this. (For all you pirates out there, the previous sentence doesn't mean what it sounds like:-)Thanks
For my peninsula I used shims instead of bolts. I didn't want all that weight concentrated in just a few places...
my peninsula construction page
If the floor settles or rises I can pull the shim out and replace it with another.
Regards,
Charlie Comstock
I started out in a modular club and we used 4" eye bolts with T-nuts. I wanted a flatter footprint and the elevating bolts would have worked great, but I could never find any long enough. I also had problems with the T-nuts coming out of the legs. This is what I do now:
I get a long (3 or 4 foot) piece of all thread, nuts, some fender washers, and some coupling nuts (1" long nuts used for coupling pieces of all thread). I place nuts on either side of the washer to hold it in place while I weld the nut to the washer and then this assembly to the all thread. I back off the nut from the bottom of the washer and cut the all thread flush with the washer. I also weld a washer to a coupling nut and this gets installed in the base of a 2x4 with a deep hole drilled in it. The washer allows the leg to support a lot of weight without the coupling nut moving farther inside the leg.
I have seen a lot of variation in interior flooring and would recommend allowing at least and inch or to adjustability up or down from its center position.
bnsf76
Just wanted to add a suggestion - if you're using height adjusting bolts on carpet, I recommend placing a brick or paver stone or something similar under each leg. You can get individual blocks or paver stones at HD pretty cheap. The extra weight will help smush down the carpet in that area and will give your leg a solid, stable surface to sit on. It will also keep from leaving permanent bolt indentations in your carpet.
Also, if you've adjusted all the way out on the bolt and still need more height, you can always stick a small piece of plywood or something under the bolt to raise the layout up a little more.
Dan Stokes
My other car is a tunnel motor
I have never heard of tapered T nuts and wonder if the problem is that the hole drilled into the bottom of the leg (I use 2x2s for legs) is a bit off center and is stopping the bolt from being turned further in.
Let me clarify a bit. I use Hillman T nuts, 5/15-18 . I drill one size hole for the T nut, rather shallow, and then a much deeper hole of a slightly smaller size for the 5/16 x 2 1/2 inch carriage bolts (Crown Bolt brand).
A very small crescent wrench enables me to turn the carriage bolt when the benchwork is sitting on the floor. Frankly I obsess more about matching the height of domino to domino rather than whether the top of the domino is perfectly level.
Dave Nelson
Hi, Jim, it all depends on how uneven the floor is. Because the exhibit hall spaces we use for Free-mo setups are anything but even we start with 3" or 4" carriage bolts with rubber/plastic caps glued on, and usually have about half of the thread showing so we can have +/- 1" to 1 1/2" adjustment. On some of the floors we occasionally have to put one or more pieces of 1"x 4" shims. The idea is to cut all of your legs the same length and use the bolts for fine tuning the benchwork level. Along the walls you can also use a chalkline or laser level. Keep the shiny side up and the wheels turning! John Colley, Port Townsend, WA
From the far, far reaches of the wild, wild west I am: rtpoteet
Glad you found your problem. Won't ask where the packages were manufactured/packed.
Every once in awhile I've tried to put a metric bolt into a standard nut or visa versa. Even when they look to be the same size, it won't happen. Wonder if that is what happened.
Sounds like you are good to go for awhile anyhow.
Have fun,
Captain,
If Home Depot doesn't work.....Rockler is my 1st choice for cabinet hardware supplies.
http://www.rockler.com/product.cfm?page=1592&filter=t%2Dnut
Don Z.
Research; it's not just for geeks.
My leg adjusters are lag bolts, 3/8 thread x 3" long, threaded into 2x4 legs with pre-drilled 5/16" holes. The original design of my first 'blob' assumed a flat floor.
I'm gald I left plenty of length. Seems my floor slopes down toward the garage door, and from the sides to the center. The wood-to-floor distance varies from about 1/2" to about 1 1/4".
(When I erected the other 'blob' of benchwork, I stood the legs on the concrete floor and leveled the L girders and joists. There are no adjusting bolts under that section of benchwork.)
Chuck (modeling Central Japan in September, 1964)
Capt. Grimek wrote:Hi Don........ but apparently the only ones I've been able to find are tapered and stop the bolt once it's business end tip reaches the end of the T nut's barrel/tube. It won't go any further.
I have used the T-nuts in the past, and all the ones I've seen are threaded straight through. Since the bolt has a straight thread, the T-nut threads should also be straight thread. Therefore, I think that you should be able to thread the bolt into the nut until the bolt head hits the bottom of the nut barrel. Take a look at the nut and see if it is in fact threaded all the way. If it is, maybe all you need to do use a little persuasion.
Concerning your adjustment question, as you mentioned the big issue is the floor slope. Most basement floors are not level. They generally have some intentional slope in them so that any water will drain to one side or the other. Usually the concrete guy will slope the floor in the direction away from the sump pump. I think in your case you mentioned carpet and pad. This will be a little more floppy than concrete, and I think that the bolt head will tend to collapse the carpet/padding over time, just like the furniture cups you use under the living room sofa legs. If that happens, you will probably need a little more adjustment than if the bolt head is on concrete.
Concerning the bolt adjustment, if this were a construction job using that as a leveling device, the normal practice would be to have the bolt set at mid-adjustment (mid-travel). That way, assuming you have the top of the leg about where you think you want it, you have the lattitude to go equally from the desired position after you find out that the millwright didn't really know how to use the transit.
Lastly, if the bolt head on the floor strikes you as a little flimsy, there was an idea in an issue of MR where someone had the idea of using a 1-1/2 inch diameter plastic pipe cap. The blank end of the cap was drilled with a clearance hole to pass the bolt. The bolt was inserted up into and through the hole. A nut sized to fit the bolt was then screwed onto the bolt and tightened to hold the assembly together. You might want to use a little Loc-Tite to keep this nut from loosening later. Anyway, what you end up with is a large diameter surface to sit on the floor, and also a convenient place to grab the thing for vertical adjustment.
Hope this helps.
Regards
As long as your floor is fairly level 1 1/2" bolts should be long enough. 3/8" bolts can hold a lot of weight, I see no problem there even if you are using concrete, like I saw in a MR article from the early 50's. They hold some pretty heavy stuff in agricultural equipment that pounds on them a lot harder than anyone will ever pound on your layout (I hope). If you have a rug or carpeting on the floor I'd recommend using the little protective cups like you would put under any other piece of furniture to keep a narrow bottomed leg from sinking into the carpet.
Remember the bolts are for leveling, if they need to stick out to make the layout level, they need to stick out. Start with them in all the way and lengthen those necessary to get a level layout. If the looks bother you to much, put a curtain around the layout to hide them and all the other stuff you can hide under your layout.
Good luck,
The stability (or lack of) is dependent on the construction method used to attach the legs to the benchwork. A 2x2 leg 3' tall attached with no cross or diagonal bracing will transmit a lot of lateral or horizontal motion into the benchwork. So, without knowing how you made your legs or how they are attached, I cannot state that yours will be stable if setting on the bolts. A 3/8" bolt is pretty good sized, so I wouldn't worry that the bolt can't handle the job.
Edit: Regarding the t-nut keeping you from sinking the bolt all the way into the leg: You have to drill a hole for the barrel of the t-nut to go into the leg. Simply drill that hole as deep as the bolt is long and then you'll be able to sink the bolt until the head is against the bottom of the leg.
Captain, my Captain,
I screwed the adjustable feet all the way up into the leg and then started with a 6' level, checking in several directions across the top of my benchwork and adjusted the feet until the benchwork was flat. I didn't see any sense in trying to guess beforehand how much to extend the feet without knowing if the floor was close to level (which it wasn't). I also used 1 1/2" length for the leg bolts.