I need a construction engineer

Discussion in 'Getting Started' started by KentBy, Feb 14, 2008.

  1. KentBy

    KentBy GN, NP, SP&S

    I was almost ready to start my bench work and was looking at starting on my flat wall (no doors and windows).
    I got out my stud finder and can find almost no nails. How did they build this wall?
    I am in a finished daylight basement. The wall is concrete and holds back the dirt that is also under the garage. I probed with a nail where I had found a nail in the Sheetrock and found that the Sheetrock is about 1/2 inch thick. Next I probed with a nail about three inches to the left and missed the board. The nail when in 1.5 inches before it hit the concrete wall.
    This is not what I was hoping for. My plan has been to build a system as depicted in "Model Railroad Benchwork" page 22 "mounting you layout to the wall".

    My guess at this point is that the wall of sheet rock is just glued on to make the room looked finished. The Sheetrock is probably glued to 1x2 that are glued to the concrete. The may have put in a concreate bolt at some points, but I can't many places that the stud finder will pick up on.

    Now the question becomes, can I mount to the walls some how or do I need to build the bench free standing. I was hoping to be able to slide a work desk under the bench when not in use. Also I want to do multilevel and didn't want supports on the front side of the lower bench supporting the upper bench.

    Any ideas?

  2. MasonJar

    MasonJar It's not rocket surgery

    The stud finder doesn't necessarily find just the nails or screws, it should find the denser wood stud itself.

    It is possible though that the drywall is fixed to simple strapping (maybe 1x2), but even so, you should be able to find those. They are likely on 16" centres, but may be on 20" or 24" since they are only holding drywall up, not the floor(s) above.

    In the end, if you cannot find any strapping or studs, you might be able to affix the benchwork to the concrete foundation directly with long lag bolts. This is probably not desirable since it will create a conduit from the foundation right into the basement.

    The other possibility that occurs to me is to create a freestanding framework in the shape of a "C" that would eliminate the front leg of the benchwork, but not entirely free up the space.

  3. Go Big1

    Go Big1 Member

    When you say that you probed with a nail about three inches to the left and missed the board, I assume that you mean that when you pulled the one nail in the sheetrock out, and probed, you hit a piece of wood. Then when you went 3 inches to the left, you went through the drywall, hit "air", and then the concrete wall.

    If the above is correct, then you have a pretty typical drywalled basement wall. What has been done is some type of wood (say a 1" x 1") has been fastened to the concrete wall. Typically this wood will run vertically from the floor to ceiling. These pieces of wood should be spaced approximately 16" apart. This is called installing the "frame" or "studs". Once this is completed, the drywall is then nailed into the studs.

    So, if this is all still making sounding plausible in your situation, what you need to do is determine where each stud is, then anchor your benchwork at those specific points.

    Good luck!
  4. ezdays

    ezdays Out AZ way


    I think your assumptions are correct. They may have used furring strips and used Liquid Nails or panel adhesive to join the sheetrock and strips to the wall. The reason being is that the sheetrock nails might be too long and would hit the concrete before they went in all the way.

    I would not rely on holding up the benchwork from either the sheetrock or the furring strips. Rather, I'd try to fasten it into the concrete wall behind it. There are several different kind of fasteners you can use including a nail gun that fires the nail into the concrete, or even what is referred to as a "red hat", where you drill first then hammer the fastener in. There are inserts that you can use, then screw a lag bolt in, but in all cases, the fastener goes into the concrete. Regardless of what you do, I would not rely totally on that to hold a cantilever shelf on the wall without some supports or legs going to the ground. Otherwise, anyone putting any weight on the edge of the layout will cause it to move and possibly break.
  5. tetters

    tetters Rail Spiking Fool!

    I was in a similar situation except I was looking at a brick and mortar foundation. In the end I opted for free standing benchwork. One reason was cost, I already had the lumber. The second was it ended up giving me some much needed shelf space. To store tools et al.

    An option I had considered before hand was to do as has been suggested, except I was going to drill holes into the mortar joints, using a syringe squirt some epoxy into the holes and then sink Concrete screws into the holes securing a shelf bracket to the wall. The shear strenght of each screw was 200 lbs. 3 screws in each bracket. Plenty strong enough to hold up my bench work. In your case I drill right through the drywall and strapping and secure the concrete screws into the concrete wall with 2 1/2 screws.
  6. Go Big1

    Go Big1 Member

    Don, good points on the using liquid nails to adher the sheetrock to the studs. However, I really don't know what type of glue/adhesive could be used to adher the studs to the concrete wall. I would presume that the studs are securely anchored into the concrete wall, and at least perform some sort or trial to determine so. Maybe anchoring a lengthy piece of 2x4 into a stud, and seeing how much weight can be put onto it?

    If the studs can support the weight, I think that would be the easiest alternative for affixing the benchwork.
  7. rogerw

    rogerw Active Member

    Liquid nails will secure the furring strips to the wall by it self. We put many sheets of plywood up at work when we are building our telecom. rooms on campus. Put liquid nails on the back of plywood and then use tapcons to hold in place until liquid nail dries. afterwards we have taken the screws out and the liquid nails to cement bond is unbreakable.
  8. ezdays

    ezdays Out AZ way

    I have seen people glue furring strips to concrete, even Liquid Nails would work. I would think he should detect nails or bolts with the stud finder. But, assuming that they are fixed to the wall using cement nails, I don't think that there's enough thickness to the wood to secure a ledger board to it. It probably would suffice if he didn't depend on it to support the whole weight of the bench. I'm still recommending legs in front, then he could use the strips to secure the other side.

    I have part of my layout secured to the wall studs using wallboard screws, but I also have legs in front to keep it from moving and to support the weight.
  9. KentBy

    KentBy GN, NP, SP&S

    I talked to the local Ace hardware guy...

    He sold me a concrete bit and two piece inserts that go into the hole in the concrete about 1 inch. Then a lag bolt will go through a washer and then my 2x2 stud placed on the outside of the sheetrock. I plan on running the 2x2 floor to celling, and then support the bench from these.hamr

    The lower level will probably be at 36 inches off the floor and extend about 36 inches out from the wall. I will place a diagonal brace from the outside of the bench back to the 2x2 stud. This should run about 10 feet before joining with bench work on the other sides of the room.

    The top level will be about 72 inches high and extend out about two feet. I want to brace this with a diagonal from the top (87 inches from the floor) at about is midway point. The diagonal braces would be hidden behind senery and leave with 12 inches for track in front.

    Each 2x2 stud would be place at 4 ft spacing to allow me to put my desk under it between the bracing. If I use the L grider system, I think that this would be strong enough.:excited1:

    I am still open to suggestion if someone thinks that this is a bad plan.

  10. tetters

    tetters Rail Spiking Fool!

    So how many holes do you figure you'll have to drill?
  11. KentBy

    KentBy GN, NP, SP&S

    4 studs (2x2), Three holes each.

    Of course that doesn't count the hold that go in the other wall which are normal 2x4 stud walls (I hope).wall1

  12. tetters

    tetters Rail Spiking Fool!

    Sooo...how many holes? The only reason I ask is that unless you have a Drill Doctor to sharpen your masonry bits, after a dozen holes or so, that little sucker is going to get duller then a game of lawn bowling in two ft of snow...(no offense to lawn bowlers). So you might want to pick up one or two spares...you might also snap one.

    Oh...and you are using a hammer drill with the masonry bit for the concrete wall right? Because, if you use a regular drill, the bit will dull in no time.
  13. KentBy

    KentBy GN, NP, SP&S

    Thanks for the heads up tetters.

    My Ace drill bit is 1/2x6 masonry with a carbide tip. Hope it stands up because I don't have a drill Dr.:cry:
    It says that for use with hammer or rotary drills, but I only have a rotary.
    I will first drill through the 2x2 and sheet rock with a regular bit and then remove the 2x2 and finish up in the concrete with the new bit.

    How it lasts. Anyone around the Portland Oregon area have a drill Dr that I could borrow?:wave:

    Or I could just buy another one at $6.49.

  14. tetters

    tetters Rail Spiking Fool!

    With a regular rotary drill try and pick at the concrete with the bit. Don't get crazy, but take your time and apply pressure, then release...do this often while driling your holes. Constant regular pressure will cause the bit to dull in a hurry. It's not only the material that will dull the bit but the heat from the friction being caused.

    You should by a least a couple more of the bits if you have a lot of holes to drill into. Alternatively, you can get a home-use hammer/rotary drill for about 40-50 bucks...and they work great for light hammer drilling around the house. I have a regular hammer drill with a 1/2" chuck for the heavier stuff which I occasionally find myself doing. But I also have one like this which is great for double duty when working quickly. It cost me 50 bucks, however next to my keyless rotary chuck drill it gets a ton of use when I'm working on a project. Plus it saved me a ton on bits which can get expensive after you've bought a few of them.

    Just my two cents.
  15. Triplex

    Triplex Active Member

    A little deep, but since it's so low, maybe not so bad. And you will be able to lean over it, because the upper deck is so high.
    I gather you'll have some sort of step up to view the upper deck?
  16. KentBy

    KentBy GN, NP, SP&S

    Maybe I will need to adjust the sizes a little.

    I planned that I would have a 1 ft movable platform that I could step up onto. 72 inches maybe a little high. if I brought that down to 66 inches I would be able to see most everything without the step, but would still need it to work on anything that is back from the edge.

    As a general rule with multi level layout construction what would be the best stragegy?

    1. Build the upper level first, then the lower level.
    2. Build the upper level first, but down low, then move it up to the correct height.
    3. Build the lower level first, then the upper level.
    4. Build it all at once.
    5. ????


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