Tank bracket problem

[Craig Winnerman]

I just ordered 2 aluminum rails, 8 tank brackets, and 2 spear gun holders from MaxHolding Systems. I think they are identical to the roll control product. My dilemma is how to mount the rails to the side of the boat. Color me stupid..lol I assumed just use some stainless steel pan heads, but this will prevent the tank brackets and other accessories from being able to slide in and out. In order to adjust the tank brackets for different size tanks, the need to be removed from the rail. I have tanks from 63's to steel 112 's. Another option considered is liquid nails or 5200, but not my 1st or even 3rd choice. The other option would be to counter sink the screws, but not much thickness in the aluminum tracks and a lot of work.

Why does roll control and maxholding systems rails not come with pre drilled counter sunk holes spaced every couple of inches.

Any other suggestions???????????

 

[matt_unique]

My roll control system came with holes drilled out such that you can countersink the screws. I setup my system to carry two sets of doubles and 4 AL 80 tanks. So far I have not had to adjust them.

I would not want to risk the weight and possible damage from falling tanks with any kind of glue on this system. You should use ss bolts and bolt the tracks to the gunwale.

 

[Craig Winnerman]

my rails are not predrilled. I think I have decided to bite the bullet and drill and conter sink holes in the rail and mount using very expensive Toggler Snaptoggles.

 

[Nemrod]

My rails were not predrilled either. I countersunk mine at three locations for stainless screws. Since I am in aviation countersinking is nothing new to me and was not a problem. I used three screws per rail BTW. I think countersinking is yiour best option. I also ran a bead of 5200 behind the rails and let it ooze out and then cleaned it to help prevent the rails from wobbling or working. My aluminum rails from Roll Control were thick enough to countersink. I believe I used 1/4 inch hardware or perhaps 5/16ths. If it is important I will go check for you. N

 

[Nemrod]

BTW, aviation type countersinks that have a pilot to guide will produce a superior hole without wobbling and gouging. The shoulder angle probably wil not match common hardware but it does not matter. In any case you want a piloted counteresink if at all possible.

A secret to good countersinks, use a phenolic board or MPF plank behind the workpiece. Drill a hole at your locations in the workpiece (rail). Drill a matching hole or a hole in the MDF that is the same size or slightly smaller than the pilot of your countersink. Set the workpiece over the hole in the MDF so they align and then clamp and do your countersink. Unless you have a depth setting cage you will be doing it by eyeball either with a hand drill or preferrably a drill press. Stop and check frequently so that the result is the screw head is exactly flush. It will look ugly if it sits low and it will interfere with the accesories if it is proud.

N

 

[Jon Nellis]

The best countersink bits for aluminum are the type with a hole drilled/cast into it, using one edge of the hole as the cutting edge (hard to explain, you'll know it when you see it) the second best option are single flute countersink tools. Multiflute countersinks make a mess in aluminum, even in a mill. Use high speed steel bits and WD40 for cutting fluid. Carbide tools don't work as good for Aluminum as they tend to gall a little easier.

 

[Chuck Tribolet]

My Roll Control rail is bolted on with 1/4-20 bolts.

Good info about countersinks -- I've always had trouble with a multiflute countersink
chattering in aluminium, even in the drill press.

 

[Nemrod]

It is true that a single flute type as described by one poster will do a better job but for our non professional purpose countersinking of a dive tank rail a double flute will do especially in a press. Use a little parrafin on the cutter. A perfect countersink is not needed. N

 

[Chuck Tribolet]

British paraffin (US kerosene) or US paraffin (candle wax)?

 

[Nemrod]

Candle wax, it is a lubricant. BoeLube is a better parraffin type lube if you want to purchase a "product." N