Drilling into slide floor

[thejonr]

Hey all, I am building a new U shaped dinette for our dinette slide in our 2008 Melbourne 26A. I've come to realize that there is a thick piece of metal in the subfloor. Assuming it was steel, I have been attempting to slow drill it using a carbon hard metal bit with no luck. After 2 hours and a lot of pressure, I had 1 hole.

Any suggestions for what I might be doing wrong? I'm lubing the hole regularly, drilling at a variable slower (1500-2500 rpm) and putting even pressure (maybe sometimes too much pressure?) What the heck is this floor made from??

[Jagiven]

How big of a hole are you drilling? My recommendation, start with a small drill bit and keep stepping up. Smaller the drill bit higher the speed.

Make sure to have sharp drill bits. Cheap drill bits often do not have a good edge, nor hole an edge.

[thejonr]

Originally Posted by Jagiven

How big of a hole are you drilling? My recommendation, start with a small drill bit and keep stepping up. Smaller the drill bit higher the speed.

Make sure to have sharp drill bits. Cheap drill bits often do not have a good edge, nor hole an edge.

The hole is only 5/32in, so pretty small. With that size I should be upping the speed more? Here's a photo of the same bit, obviously bigger. But purchased brand new

[gprapim]

Originally Posted by thejonr

Hey all, I am building a new U shaped dinette for our dinette slide in our 2008 Melbourne 26A. I've come to realize that there is a thick piece of metal in the subfloor. Assuming it was steel, I have been attempting to slow drill it using a carbon hard metal bit with no luck. After 2 hours and a lot of pressure, I had 1 hole.

Any suggestions for what I might be doing wrong? I'm lubing the hole regularly, drilling at a variable slower (1500-2500 rpm) and putting even pressure (maybe sometimes too much pressure?) What the heck is this floor made from??

I ran into the same situation in my GreyHawk, not for what you are doing, but for another reason. I have no answer for you. I think it’s armour plated (lol).

[thejonr]

Originally Posted by gprapim

I ran into the same situation in my GreyHawk, not for what you are doing, but for another reason. I have no answer for you. I think it’s armour plated (lol).

Haha right?! I mean what the hell is this thing made of. The only thing that could possibly help is the lube that I'm using. The local Ace didn't have drill lube so I'm using a turbine lube? I've also tried WD40 with worse luck (bit started smoking pretty quick). I'm really stumped.

So far I've got everything screwed into the 1/2 ply above the metal but if I can find a solution, I'd really like to get this thing locked in better.

[ALJO]

High tensile steel might be hard to drill, have your grinder at hand and sharpen regular. Be sure the bit will cut instead of riding on it cutting edge.