Height Adjustment Leg Bolts

[Capt. Grimek]

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

[Don Z]

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.

Don Z.

[Capt. Grimek]

Hi Don. Thanks for the snappy reply!
I realize that the proof is in the leveling, but I'm a tad disturbed that all of the bench's weight would be
pushing down on and "balancing" on a spindly looking bolt (even if it is 3/8") rather than on the bottom of the legs themselves sunk into the carpet (untii and if I end up needing the bolts at all.) I was going for the approach you used, but the T nuts (threaded inserts) don't allow me to get the head of the bolt anywere near the wooden leg bottom.
I was concerned about stability when someone bumps up against the bench work during operations later.
Figured the head bolt and leg bottom, sunk into the carpet until and if needed would be the best approach?

I think these T nuts might work better with 1/2" or 3/4"bolts and allow 3-4 thread's adjustment.
I'll experiment. I'm going to the Home Depot, next town over tomorrow to buy bench work starting lumber.
(At last!) Figured I'd ask around. With just lag bolts, I'd have started with the heads flush against the bottom of the 2x4s but the T nuts made that impossible with 1 1/2"ers.

I guess, my REAL question is, short of insanely unlevel basement floors and earthquake damaged houses, what's a realistic adjustment span on average for when you find out your carpenter didn't get the floor spot on level, or normal house settling over the years on the lst floor level. I'm thinking if you have to adjust more than say a quarter of an inch you have bigger troubles? As is, the bolts still protrude at least an entire 1 " from the T nut.

[Don Z]

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.

Don Z.

[Capt. Grimek]

Hi Don.
I thought I could simply thread the bolt up into the wooden leg past the T nut as you've said, 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.

So, in that event, would you recommend that I find
shorter bolts that'll start out by resting up against the T nut and leg bottom? I just want to be sure how many threads and adjustment distance to allow. After 3-4 threads are backed out, the bolt already gets a tad wobbly in the T nut barrel. The t nuts only allow about 1/2" of bolt "take up". Think 3/4" bolts would be the way to go in this instance?
Thanks very much.

[cowman]

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,

[Capt. Grimek]

Hi cowman,
The problem I'm having with these T nuts, is that the bolt won't go all of the way in (to it's head) as a starting point. The T nuts appear to be slightly tapered. I'm using standard hex bolts and don't think they're tapered-are they? I'll try a different kind of bolt tomorrow at the store, but I think it's these T nuts.

I really wanted to go with threaded inserts rather than just a lag bolt into the wood but these aren't cooperating at all so far. They go in a max. of maybe a 1/2" and stop. So it's spindly legs or nuthin'.
I may have to return them as I really want a flush to mostly flush (wooden leg/bolt head only, against the carpet) as my starting point and adjust from there.

[maxman]

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

[Capt. Grimek]

Thanks Maxman. I like the pipe cap idea. I've tried persuasion and these tanged T nuts certainly appear to be tapered at least to the point where the bolt end will thread in only as far as the bottom of the T nut barrel. I wonder if the T nuts with the tack nail holes in the outer ring allow "us" to thread through past the T nut's barrel end and further up into the wood... I'll try them out tomorrow.
There just seems to be a very minimal allowance for any adjustment here. I think I'll try some different
T nuts and bolts out tomorrow. The stores only had a couple of the other type of T nuts but I'll see if a bolt
will go all the way through them or not.
This didn't turn out to be as simple and handy as I'd expected.

Thanks for the help everyone. I truly appreciate it.

[tomikawaTT]

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)

[Don Z]

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.

[Capt. Grimek]

I found the solution. Sorry it turns out to be something so dumb but here goes.
After struggling with the pair from one sealed plastic bag, I finally decided to open another (out of 20 bags
I'd brought home) and try them. They fit and work perfectly! The bolts indeed extend all the way through to the head. My caliper is on loan, but all I can think is that the original two from the lst bag were mislabeled
and are not really 3/8" or are otherwise defective in some way.

Before I go back to Home Depot tomorrow, which is a 20 mile drive, I'll try all of the Tee nuts from the other bags to be sure.

Jeez, ya can't believe what you read on a label anymore!

Thanks SO much guys. I thought I knew how T nuts were supposed to work and that hex bolts are not tapered (normally) so I couldn't figure out what I was doing wrong here. Turns out, nothing.

Thanks for the additional hardware supply link. I'll check them out. The diagrams from their tee nut page
from the link gave me the light bulb idea to try another bag of tee nuts.

You guys are all awesome. Thanks Chuck for your tale of adjustment extremes you had to go through
in a garage! Guess I'll leave plenty of room for adjustment, now that I can get the head bolt all the way
in as a starting point.

Have a GREAT weekend everyone.

[cowman]

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,

[R. T. POTEET]

Go to a hardware store - HARDWARE STORE - and look at an elevator bolt; once you gaze upon one of these things you will slap yourself on the forehead - please remove the bolt from your hand prior to doing so - and realize that standard carriage bolts just don't quite feed the bulldog. They are just a little more expensive than carriage bolts but they have an absolutely flat bottom surface that is about an inch and a half in diameter and is designed for - are you ready for this? - elevating which goes far towards explaining why they call them elevator bolts.

[johncolley]

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

[dknelson]

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

[stokesda]

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.

[Capt. Grimek]

Thanks for the additional info. and advice guys.
Thanks for the education regarding elevator bolts Mr. Poteet. I'd seen them before, didn't know what they were called and had checked around online a bit. As I cruised the aisles in the fastener dept. I looked for them and/or something similar but didn't see any on the box fronts/shelves. Guess I'll go back to the
HARDWARE STORE :-) where real and experienced people work.

dkNeslson, I hadn't installed or drilled into wood yet. The problem as I discovered after several posts was that the wrong sized tee nuts were inserted into the sealed bag at the manufacturer or else smashed just enough to capture the bolt ala tapered stop. After seeing the link depicting tee nuts and hex bolts kindly given to me by Don Z, I thought to try another package and voila! I'm going through each and every package before going back to the store.
Once I find and switch to elevator bolts I should be golden now.

Hi John, I can see now, even though I'm not in the modular/portable world that we need to be prepared for some fairly extreme elevation differences. I live (as do you) in earthquake territory so even if the house doesn't fall over or look much different, I could indeed end up with a fair amount of leveling elbow room someday.
I'm still planning on making it over for a visit once I get the room prepped and the lumber set up.
Dan, I've been thinking about "toothed" casters at least. Want some non sliding bite, but my wife the gardener has enough paving stones and fragments around that I can try 'em out.

I'm constantly amazed and gratified how giving everyone is here even for the relatively dumb questions
that (at least should) have somewhat obvious answers!

G.

[bnsf76]

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

[BCSJ]

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 

[ericboone]

www.mcmaster.com

Goto catalog page 3103 or just type "elevator bolts" in the search form on the left side of the page. 

[JulesB]

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

 

[mfm37]

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.   

[Capt. Grimek]

Well, my store knew what Tee nuts were and had some but never heard of elevator bolts. I'm off to the sites you guys have recommended to me if my local hardware stores don't satisfy.
I sure do miss the Mom and Pop stores of my youth where people who worked in the trades owned and operated them.
It's interesting to hear and see the different approaches people take for their heigth adjustments.
My next questions is: Is typical lumber store lumber as incredibly knotty as Home Depot/Lowes lumber is?