How to fasten slats to a metal garage door frame?

[nonsibicunctis]

Help!
I bought a couple of garage door frames from Bunnings some time ago.  I had erected them and clad them with 7mm marine ply.  Unfortunately, it wasn't effective and after a while it started to buckle and eventually became so bad I had to pull it off and replace it.

The door frames are steel, I believe and made of about 20mm square tubing.

I received advice that wooden slats was the best option and I obtained 19 x 100 pine slats and after a sand to smooth, undercoated and top coated them with exterior paint.

I was advised to use galvanised 8g -18 x 32mm wing screws for fixing and to put 2 of each into top, middle and bottom rails and that the were self tapping and I shouldn't need to drill pilot holes, that they would just screw right in and I wouldn't need to drill pilot holes first.

Today I went to start the job.

* I clamped the first slat to a frame

* Tried using a cordless drill and bit to drive the first screw - it went through the wood but made no impression on the metal.

* I tried using a corded power drill but again without success.

* I then drilled a pilot hole slightly smaller than the screw diameter.

* I tried driving a new screw by using the pilot hole but again it was unsuccessful.

Obviously, I am doing something wrong or have the wrong screws or ?

Both of my drills are in good order and working fine on other jobs, they are not old and worn.

I used a new, for metal, 4mm bit for the pilot hole.

So, I'm not sure what is the problem?

Do I need different screws?

A better quality bit of a particular type?

Some form of lubricating oil for the screwing into the metal?

  

Can anyone advise me what I might need to do, please?

[MitchellMc]

Hi @nonsibicunctis,

That sounds about right, and yes, @Nailbag is suggesting you pre-drill the steel aswell with a 3mm drill bit. I'd pre-drill the timber and then clamp it in position on the steel frame. Use the pre-drilled holes in the timber as guides and drill through them into the steel.

Mitchell

[Nailbag]

Hi @nonsibicunctis 

@MitchellMc has kindly answered those questions for me. Just bear in mind that installing the timbers on the frames while they are off the posts, is that they will be extremely heavy to refit. You will need a couple of helpers to support the weight, while you guide each one to the hinges.

Nailbag

[nonsibicunctis]

Thank you, Mitchell

[nonsibicunctis]

Nailbag,

Thank you once again.  Yes, the weight issue is something that has concerned my thinking.  I have neither family nor friends & cannot afford to pay a tradie to do this, so like it or not, have to sort it myself - something I've had to do for a very long time in a society, sadly not reflecting of the type of help that you and others have given me here.

So, I'm going to try drilling with the frames in place again.  My intended process:

1.

* Using one slat square and clamped to the frame at the level I need to leave clearance at top and bottom.

* With slat in appropriate position, mark inner inner levels of bottom of top and top of bottom of frame across slat.

* Add small piece of timber across slat at marked level

* Mark line centre line of frame across front of slat at top, centre, and bottom frame rails

* Drill 4mm holes through the slat at appropriate place at centre, middle and bottom rails of slat (i.e. at the centre line)

2.

* Check the slat fit at either ends and various points in between to ensure accuracy

* Assuming all is correct, use that slat as a template for all the others

* Drill 4mm holes through all slats

3.

* Position template slat on frame and clamp.  ( I intend to start at hinge-side and work towards centre)

* Using pre-drilled holes as guides to mark frame for drilling

* Use a spacing rod and clamp next slat to frame and mark frame holes 

Repeat as above for all slats

4.

* With all slats now pre-drilled and frame marked

* Drill 3mm pilot holes in steel frame at marked positions

* Attach slats with non-winged steel screws as you suggested

The thinking and hope behind this process being that all the pre drilling will give enough accuracy and assistance to allow me to affix the slats with the self drilling screws.