Double wall pipe installation - Self-tapping screws questions

[Mikeyvon]

I am installing the stove pipe for my new house. The stove is a Hearthstone Phoenix. I am using double wall pipe with slip joints. It came with 1/2" self-tapping screws, but I have not been able to get them to go in. The self-tapping part does not seem to work very well. I am trying to install these using hand tools.

Do I use my impact screw gun?

Drill pilot holes? If I drill pilot holes, do I need to be careful not to puncture the inner wall of the pipe?

Silly questions I know, but I have heard that the pipe is easy to strip out (that is why I have been trying hand tools). I just want to do it right.

michael

 

[Highbeam]

The men that installed my simpson double wall used the standard battery powered drill/nut driver deal with the standard little chuck clutch set to prevent stripping. I would use the power tool to start the screw and then finish tightening it with a hand tool. This will prevent overtightening but also minimize the chance of the power tool scratching the paint on the pipe.

They were able to depend on the chuck clutch to prevent stripping since they do it all the time.

 

[gpcollen1]

yup - use a drill. The head is the mini drill bit. Hand tighten - do not tighten with drill.

 

[Mikeyvon]

CTwoodburner - Just so I get this right, are saying use a drill and a small drill bit to make a pilot hole or use a screwgun/drill to let the self-tapping screws start the whole then hand tighten?

 

[bayshorecs]

+1 to pilot hole

 

[gpcollen1]

Sorry - the self tapping screws are the drill bit. i meant use the drill to screw or drive the screws (not sure what type of heads they have0 into the metal. You'd be surprised what those things can drill through.

 

[bayshorecs]

Careful with too much pressure and damaging the pipe trying to get the self tapper to bite. Unless I can really put some weight behind them, I make a small pilot hole first.

 

[fossil]

Some screws are just "self-tapping"...virtually any sheet metal screw. They generally need a small pilot hole. Some screws are made to be "self-drilling"...they have a couple extra ground "teeth" in a sharp point, the intent of which is to eliminate the need for the pilot hole. I invariably take the time to drill a small pilot hole, because I want that screw to go right where I want it the first time every time without skittering all over the curved surface of the pipe. To prevent drilling deeper than I want, I use a short piece of a broken bit in the drill chuck. If I don't have one, and it's important to me, I'll just break a little drill bit in a vise. Small bits are cheap. Rick

 

[Mikeyvon]

I think I will drill pilot holes.

Do I have to be careful about piercing the inner wall of the double wall?

On the adjustable length part, I secure those joints with screws also correct? (I searched that last night and some people on some threads said not to to allow for expansion).

 

[DAKSY]

Do I have to be careful about piercing the inner wall of the double wall?

Yep. You only want to penetrate the outer shell

On the adjustable length part, I secure those joints with screws also correct? (I searched that last night and some people on some threads said not to to allow for expansion

Expansion? NOT. Screw them together...the ABSOLUTE last thing you want is the slip section to come apart in the middle of a burn...

 

[pinewoodburner]

My instructions for the double wall stove pipe suggested drilling a small pilot hole, but not to go into the inner pipe. It is pretty simple to drill and you will know when the hole is made and you can back the drill out.

 

[jtp10181]

Sharp tipped zip screws work good... All the Simpson pipe comes with it. They go right in with a power drill. A good sharp screw will go through think sheet metal faster than a self tapper.