Screw selection?

[David Winton]

Building a bench using 1.5" reclaimed heart pine, a wood that is actually harder than oak.  

Using the Kreg HD jig.  The 2.5" coarse thread HD screws are pretty finicky about going in to this hard wood.  Torque setting seems not to matter.  Some go in like butter, some get halfway in and then the drill clicks away refusing to go any further.  So I have to back out and scratch my head.

So I would like to try a fine thread. But Kreg appears not to sell a 2.5" fine thread with the washer head.  Then when I looked elsewhere online, it seems that a 2.5" washer head fine wood screw is something of a unicorn.  

Not sure if I'm looking for the wrong screw or just looking in the wrong place.

Thanks for responses. 

[KregRep]

David,

Most screw manufacturers do not make a screw that long since they have a smaller diameter and the percentage of breakage increases exponentially once you get past 1 1/2" long. The best thing you can do is to drive the screw part way in and then back it out. This will clear the material out, making it easier to drive. Another option would be to coat the threads of the screw with either a beeswax or soap to lubricate the threads. This will allow them to enter the wood easier. A final option is to pre-drill the hole with a 1/8" drill bit. This is fairly difficult to do, however, as you have to follow the angle of the pocket hole. 

If you have further questions, please do not hesitate to contact Technical Support at 800-447-8638 or [e-mail] for assistance. They will be more than happy to help.

KregRep

[Ken Darga]

"Screw-lube" works for me.

Apply it to the screw threads---

drive screw in until you feel resistance---

back out---

redrive to seat screw.

Higher torque is needed to drive the screws into harder woods.

I don't use soap---soak retains moisture.

[David Winton]

Thanks so much KregRep.  Though I'm pretty sure that's not your real name.  

Isn't there a slightly wider (diameter) screw with the same X x 2.5 version in a fine thread version?  Not really sure why this would not exist.  What if I were joining 4x4's hardwoods? 

Anyhow, assuming not, I should continue to use the 2.5" coarse, following your instructions? 

[David Winton]

Thank you Ken.  Your response preceded my other response. Will try that lube process.  

Ken Darga said:

"Screw-lube" works for me.

Apply it to the screw threads---

drive screw in until you feel resistance---

back out---

redrive to seat screw.

Higher torque is needed to drive the screws into harder woods.

I don't use soap---soak retains moisture.

[phillip Dare]

When I have to use screws in any kind of wood I always use a bar of soap. Wet it down and rub screw along it. The soap makes the screw slip easily and when the screw is home the soap has dried it bonds well.

[David Winton]

Thanks all.  

[Lance Kentner]

David, I'm pretty new here but I have a couple of thoughts for you... One, you can try drilling a slightly deeper pilot hole, or even go up to the next larger drill bit size... And two, have you tried using a little thread was on the screws before you drive them in??