securing building form to a concrete floor

[P-man]

i'm getting ready to restart my long delayed project (14' v-bottom) and am trying to decide how to attach the building form to the concrete floor of my shop. before i moved, i had used a power driver to nail 2x4s to the floor, but i would prefer to not tear up the floor. any suggestions? thanks.

[Rich VanValkenburg]

When building my Nutshells, I first built a couple of sawhorses that had zero movement, and exact in their leg sizes. Then glued those to the floor with a few squirts of liquid nails-type adhesive after setting them up level with planet, and waited a few days for the stuff to set good and solid before I started the boat.

Not saying that's the correct way, but I had the same concerns as you do.

[Bruce Hooke]

Rich's solution, or some variation on that idea sounds to me like a good way to go. However, if you want a stronger connection to the floor than glue can provide then I think I would go for Tapcons over nails since Tapcons at least leave a fairly clean hole that should be easier to patch than a nail hole. I think there is more likely to be surface damage around the nail hole as a result of chips blowing out than with drilled holes and Tapcon screws.

[Breakaway]

Not boat building, but... While building a partition wall in my garage I used tapcons and mis-drilled the first hole for the walls bottom plate. My "fix" was to countersink the hole, drive in a tapcon and a dollop of paint to match the surrounding garage floor. No one's the wiser and no real harm done. Perhaps you could consider the same "fix" after your boat build is complete. The holes would be fillled and cosmetically, its like 98-percent.

Just a thought.

Kevin

[P-man]

thanks guys. i was thinking i might use some sort of adhesive. i was not familiar with the Tapcon name, Bruce. i'll check them out. yeah, the nail holes were pretty ragged when i pulled the nails out of the concrete and the new shop has such a nice floor i don't want to booger it up.

[P-man]

thanks, Kevin. that's a good idea.

[Thorne]

If the floor is moist at all, PL Premium might be a good choice -- but you'll have to grind the last bits off afterwards unless you've got a honkin' big scraper...

[LongIslandBoy]

Can you use sand bags or cinder blocks, etc. to immobilize the building frame?

[P-man]

Floor is dry. i don't think i'd trust sandbags or cinder blocks to keep it from moving.

thanks

[CundysHarbor]

For my last two builds, I have used 2x6's with flakeboard covering as a base for the boats. It is heavy enough to not shift. I installed wedges to level the structure, nailing the wedges to the 2x6's. Good luck.
Dave

[Reynard38]

I used construction adhesive. Worked great.

[Bruce Hooke]

i was not familiar with the Tapcon name, Bruce. i'll check them out.

At least in the areas where I have lived, Tapcons are readily available at most hardware stores and lumber yards. They are normally blue and come in a few different diameters and various lengths and head types. It is important to use the right size masonry drill bit for the size of Tapcon. This size info is right on the boxes of screws and the drill bits that go with. It is nice to have a hammer drill to drill the holes but it is not essential.

[P-man]

thanks everybody. i think i'll go with an adhesive and avoid holes in the concrete.

[Candyfloss]

Good choice.

[jackster]

P-man,
My 1 1/2 cents (sorry, a little short in these economic times) worth.
Build a deck/platform.......16' X4'.....2"x3" framing.......3/4" underlayment........ fasten to that....move around for space saving!
Waddya think?

[P-man]

jackster that's a fine idea, but space is not a concern for me. thanks.

[the_gr8t_waldo]

drill holes about 3inches deep and insert all thread,nuts and large washers- this, along with gravity's help will be enought to secure the strong back and be able to level the whole works up. when the boats floating on some lake, simply pull the rod out and seal the holes up with latex cement calking. 4 or 6 -3/8ths holes will be much easyer to deal with than some glue spread out over many sq inch patches.

[JimConlin]

For small boats, I set the molds up squarely on a box beam that can be moved around the shop or adjusted in height or even tilt if wanted. Parts of the boat are not aligned to level or plumb, but square to the box beam.

[Y Bar Ranch]

I had to level my floor, so did the 2x6s to build a 6' x 20' frame with shims to bring it to level and flakeboard on top. Haven't fastened it down, but it hasn't budged over the last 5 years.