Driving screws in metal ducts

I watch YouTube videos where HVAC technicians effortless drive screws into metal ducts when there is nothing hard behind the metal to support it. I find doing this difficult. Is there a secret technique?

In my attempts, the screws "dance" around on the metal for a long time instead of penetrating. I suppose the technicians might be using thicker gauge metal than the ducts sold in home improvement stores. I think I have the same equipment that those guys use - drill/driver with hex socket, hex head "zip" screws or self-drilling screws. Maybe the YouTubers have stronger hands.

It's probably the screws. I'm still using ones made in the USA that came from an HVAC supplier decades ago and they work great.

I just use regular sheet metals screws and full-speed RPM on my drill. The screws seem to be quite sharp at the point (as my finger feedback tells me) and I do find using a previously used screw that probably isn't as sharp is more of a challenge.

Yup they have very sharp pointed ends, not prone to skidding off. 3 in every fitting and Hard cast sealant or aluminum foil tape on most all fittings.

You can get screws that are self tapping also. I find that it's really not worth the effort to reuse them as mentioned. Most screws I'll reuse but the self tapping wears out quite a bit after the first drive.

I've used screws with drill bit ends without the dancing. When using them on things other than heating ducts a drop of oil seems to help a lot.

Another trick is to not press hard when starting the screw. Let it make a little divot before giving it a shove.

jtk

I agree- probably the screws.

These work well:

https://www.amazon.com/Malco-HW8X11-...zcF9hdGY&psc=1


These, not so much:

https://www.amazon.com/dp/B01N6HTI76...hlbWF0aWM&th=1

My brushless DeWalt impact driver spins at a very high rpm and drives those hex head self drilling sheet metal screws right in with no skidding. I use a magnetic socket driver so they stay in the bit.

I have an automatic center punch that helps alot with the screws slipping.

Quote:

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Originally Posted by Cameron Wood

I agree- probably the screws.

These work well:

https://www.amazon.com/Malco-HW8X11-...zcF9hdGY&psc=1

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+1 for Malco, Made In The USA! There's no substitute for the OG zip screw. They are very sharp and hardened.

https://www.malcotools.com/

If you are using them for dust collection ducts, you are better off using 1/8"x 1/8" pop rivets, less for the shavings to catch on. Screws to hold in place till you get it right, then remove them and drill for rivets, then foil tape.

Another tip for D.C. where you can reach inside the pipe and elbows is to put as many of the rivets, tiny bolts, or screws in from the inside out. When I connect a down spout to a rain gutter I use
#6-32 stainless steel bolts and put the nuts on the outside.