# Wood screw thread choices



## APBlough (Oct 21, 2014)

Here is my plan. I am using my Kreg Jig to build a toy box with Pine and Oak. In most cases it will be connecting Oak to Oak or Pine to Pine but in one or two cases it will be Oak to Pine. 

I know you want coarse threads for soft wood like Pine but my question is; 
1) Can I use HiLo screws when screwing into Oak -or will that be too large of a risk of splitting the wood.

2)Coarse screws are for soft wood and fine screws are good for hardwood but what is the benefits of HiLo

(If you cant tell I ordered HiLo screws rather than fine thread and am just curious about it)


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## Steve Neul (Sep 2, 2011)

The only problem with the coarse thread screws in oak is the shank of the screw is smaller in diameter and is more prone to break. As long as you pre-drill the correct pilot hole for the screw you shouldn't have a problem.


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## harry nuckle (Feb 23, 2012)

HiLo screws are generally used for particleboard. Not sure if thats what you are asking but seems like you have the fine / course figured out... I personally have never tried HiLo on anything other than melamine but I feel like I wouldnt suggest it. That being said if you do try it please post the results!


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## APBlough (Oct 21, 2014)

Awesome thanks guys,
Harry yes that was what I was questioning; what HiLo were used for. I will need to return them for fine thread screws to I don't crack the oak. 
THANKS!


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## del schisler (Nov 5, 2009)

APBlough said:


> Here is my plan. I am using my Kreg Jig to build a toy box with Pine and Oak. In most cases it will be connecting Oak to Oak or Pine to Pine but in one or two cases it will be Oak to Pine.
> 
> I know you want coarse threads for soft wood like Pine but my question is;
> 1) Can I use HiLo screws when screwing into Oak -or will that be too large of a risk of splitting the wood.
> ...


use a tappered drill bit to match the screw size , will be no problum, i do this all the time , a tappered drill will let all the screw threds bite in the wood, not like just a drell bit , which only the few threds the size of the bit will bite . all my bits are from fuller company, watch their are some import's that are junk , don't match up


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## Wendel17 (Apr 20, 2009)

Just pre drill and you won't have a problem. I use coarse thread for everything. Like Steve said..drill the correct size pilot, and you'll be fine.


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## Al B Thayer (Dec 10, 2011)

del schisler said:


> use a tappered drill bit to match the screw size , will be no problum, i do this all the time , a tappered drill will let all the screw threds bite in the wood, not like just a drell bit , which only the few threds the size of the bit will bite . all my bits are from fuller company, watch their are some import's that are junk , don't match up


I second that. I have had my Fuller bits for over 30 years. 

But if your using a Kreg jig. Don't you have to use their screws? Also why not use glue and let the screws be your clamping force and use less screws?

Al


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## APBlough (Oct 21, 2014)

Yes I am using the Kreg jig and their screws. They make three thread types, and even though they are self tapping, I do not want to split the Oak by making a poor choice in thread type. I will be gluing all the joints as well to make everything stringer and not need as many screws (i.e 3 screws for the 2' section rather than 4 screws without glue) 

The main thing is they sent me HiLo 1 1/4" screws for my Oak pieces and I just wanted to make sure I had to go get the fine threads or if the HiLo would hold (and as it appears they are for particle board)


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## Road rider (Jan 29, 2012)

Al B Thayer said:


> I second that. I have had my Fuller bits for over 30 years. But if your using a Kreg jig. Don't you have to use their screws? Also why not use glue and let the screws be your clamping force and use less screws? Al


Lots of company's make pocket screws ... Do not have use kreg screws for kreg jig ...


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## bauerbach (Mar 25, 2012)

I am not sure how you would drill a pilot hole for a pocket screw... obviously the kreg drill handles 1 peice of wood, but getting into the 2nd peice of wood after that... you would need a rather long, and thin, drill bit to get the depth required, seems like it would be extremely fragile.


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## johnep (Apr 12, 2007)

The actual Kreg drill supplied with the kit is stepped to drill both main and pilot.
johnep


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## APBlough (Oct 21, 2014)

Actually, no. The Kreg jig is stepped but that is so it drilled the pilot hole in the first piece of wood along with the counter sink hole for the pocket. But it does not drill a pilot into the second piece of wood. Their explanation is that their screws are self tapping and do not need a longer pilot hole. That is the basis of my question. Since half the joint is done by the jig and the other half is dependent on the screw's self tap. So thread type would play a big role in not splitting the second hole.


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## bauerbach (Mar 25, 2012)

Ive not had any troubles with it as is. but I use it primarily with plywood which doesnt split. 

I can only think you could start the screw, just to mark the entry point in the 2nd peice of wood, and then separate and drill a 2nd pilot hole... I think the self tapping fine thread screws will be fine without though. maybe if you see the grain looks prime to splinter in that spot...


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## Al B Thayer (Dec 10, 2011)

wendell white said:


> Lots of company's make pocket screws ... Do not have use kreg screws for kreg jig ...


Well I'll be. I did not know that.

Al


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## Road rider (Jan 29, 2012)

We use between 1500 to 2000 a month thru shop 
I have used the course tread but prefer the fine tread .... Have used 1 1/4 dry wall screws when order for pocket screws was late ( ran out then ordered ) ... We use them on oak ... Maple ... Ash ... Hickory hardwoods ... And some plywood 
Have never had a problem with wood splitting ...

If your worried try a test with the oak ... Screw it together then remove the screws ... If it split it should show ...


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## Oneal-Woodworking (Apr 14, 2013)

APBlough said:


> Actually, no. The Kreg jig is stepped but that is so it drilled the pilot hole in the first piece of wood along with the counter sink hole for the pocket. But it does not drill a pilot into the second piece of wood. Their explanation is that their screws are self tapping and do not need a longer pilot hole. That is the basis of my question. Since half the joint is done by the jig and the other half is dependent on the screw's self tap. So thread type would play a big role in not splitting the second hole.


I use the same bit you describe and have no issues. :no:

For Oak to Oak you want the fine thread screws. Splitting the wood is going to be rare compared to how many screw heads break off (as mentioned above). 

This ain't so much a problem IF you clamped things down so they could not move or slide around before or during the screw breaking and IF you had more than one screw going into that particular joint. If I have an Oak face frame joint glued and clamped up tight and only one out of 3 screws break on me - I continue as if nothing happened.

The Kreg screws are not going very deep and not really holding much. The glue used and having it clamped together tightly during assembly is what makes it 'strong'. The screws are mostly there to hold the joint until the glue dries in MY opinion. 

If I go to work tomorrow and build a cabinet face frame out of oak and assemble it 'properly' - I can take the Kreg screws OUT after the glue has dried and it will still be solid and not easy to just bust apart.

You CAN also do nice joints using the fine thread Kreg screws in 'soft' woods. You just have to keep in mind that the screws are only holding things until the glue dries. :yes:

Example:









This cabinet is mostly soft as hell reclaimed barn wood. *All* face frames were assembled with the fine thread Kreg screws (different manufacturer of same type screw) and all held tight enough until the glue dried. 

Kreg screw face frames are cool in the respect that they can help you move through a lot of frames quickly AND allow you to remove the screws after the joint is done IF you need to. :smile:

The side of this cabinet has what 'looks' like a door set inside the face frame but that is NOT a true door as I would call it. It is a Kreg screwed face frame within a Kreg screwed face frame with some more barn wood run inside of all that. I was able to build this frame quickly and with very few clamps and also EASILY able to remove the screws after it was done drying so I could safely and easily mill the back surface until I got it to sit 'correctly' with all the other barn wood of the face frame...


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## APBlough (Oct 21, 2014)

*Update*

Thanks for all the input guys. I finished the toy box and using the kreg jig and the self taping fine threaded screws I had absolutely no issues. I just pre drilled everything and glues everything so that I could use half the number of screws. it all went well and I STRONGLY suggest everyone own a Kreg Jig it is an amazing tool!


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