Underwater drilling tool

[muddiver]

Buna vixtor,

If there is access on top of the mole, rent a large construction compressor and pneumatic (that is air operated) hammer drill from a construction rental company and drop the air lines down to the work site from above.

Otherwise, use a standard pneumatic hammer drill Eagle Industries 7107 General Duty Pneumatic Drill - Non Reversible - 2600 RPM | ToolBarn.com , or if the solor assembly is light weight, use powder acuated fasteners ITW RAMSET RED HEAD 721 22 caliber Single Shot Powder Actuated Tool Kit (single shot loads) - Toolup.com

The biggets problem you are going to have is applying pressure to the drill to get it to dig into the concrete. If you are swimming and not standing on something you will not be able to apply any pressure. So think about that before you get started.

 

[Teamcasa]

Reminder of the OP's situation:

but there's no way to bring electrical power over there...

use powder acuated fasteners

That may work if he can get stainless steel fasteners.

 

[Thalassamania]

We've taken two approaches to this problem: a simple pneumatic impact wrench with an in-line oiler (use olive oil so that it's biodegradable) or a Broco torch.

 

[Teamcasa]

We've taken two approaches to this problem: a simple pneumatic impact wrench with an in-line oiler (use olive oil so that it's biodegradable) or a Broco torch.

Hmm, since a (mechanics) impact wrench does not provide reciprocal hammering in the direction needed (up and down) it may not work. However, I have a few at home and I'll chuck up a drill and and try it out -

If he could bring enough electrical power to fire up a Broco, he just drill it with a large hammer drill, right?

 

[DCBC]

When in doubt you can always go with a Stanley HD45 Hammer Drill. It's designed for underwater drilling in concrete and uses 736 Skil hex bits. The unit can also be used for drilling gas/water utility holes and setting anchor bolts. Drill sizes are from 3/4 to 2 inches and up to 30 inches deep (you can also use it for core drilling up to 4 inches in diameter).

The Skil 736 carbide requires no fluid to clear holes during operation. It's equipped with a feathering valve with ABRS (forward and reverse) making it easy to start and control. Perhaps this is a little heavy for the application, but it's best to keep your options open.

 

[muddiver]

Hmm, since a (mechanics) impact wrench does not provide reciprocal hammering in the direction needed (up and down) it may not work. However, I have a few at home and I'll chuck up a drill and and try it out -

If he could bring enough electrical power to fire up a Broco, he just drill it with a large hammer drill, right?

Ultathermatic cutting rods require only enought power to ignite the strands inside it, that can be done with a car battery. The problem is the whole thing still needs a hose from a cylinder of oxygen to work.

Then there is having to fill the hole you make using the Broco rod. They are not very accurate. Sort of like driving a nail into balsa wood with a 20 lb sledge hammer.

 

[vixtor]

The place is not accessible from land, and I don't have the means to rent or put an industrial compressor and tools there. I think I will try my luck with something like:

Welcome to Gatx Industry Corporation

and hope the cement is not too tough

if it doesn't work, I'll abandon the idea probably - all those highly sophisticated tools are much more than what I was hoping to need when the idea came first to me.

 

[muddiver]

You might also consider drilling one hole, or finding a hole or natural depression in the mole (I am going to assume it was constructed of large rocks) and epoxy one steel member or reinfocing steel rod, and build a new base of concrete around that with your anchors for your instrument embedded in the new concrete. Kind of like making an anchor weight to mount the instrument on. Post photo of installation site if you want more ideas.

 

[vixtor]

The idea with epoxy sounds interesting.

 

[JKPAO]

Have you thought about a two part epoxy or cement? Many brands and strenghts are available that could hold a bolt or a stud longer than you or I would be around. Yes a Broco would for sure make a very fast job of it, as long as you don't need it to be accurate! I assume the photo cell is out of the water. So you may consider a different method to hold the cell to the MOLE.
Hose clamp, epoxy, I am sure there are ways to make it a little easier than making holes in the Mole.
See you topside! John