Split Wood on Face Frames

[Eddie Kirk]

I am having a issue with spliting face frames when using Kreg screws.  I am using 1x2 oak and a 1 1/4 inch fine thread screw like the chart says.  Any ideas what I am doing wrong?  I am considering going to a 1 inch screw or changing the depth.

[Jay Boutwell]

Hi Wayne. I'm sorry you are having all the troubles with your project. From what I saw in the examples that you supplied is leading me to think that your trouble is with the lumber and not your method. I did see what you are talking about. The sample I photographed and posted are made the same way yours are. The screws are entering the material and running across the grain like yours. The only difference in mine and yours that I can see is that mine might be a little bit lower on the location of the screw entrance. In my sample the screws enter dead center with the stile piece which might give you just a bit more wood above the screw but not that much. I know that maple can be a bear at times depending on it's grain structure. Fortunately I have never had the trouble.

There is one trick I can share with you that might aid in getting the screws into the joint. I have done this before when I was driving screws into what I knew was dry and very brittle wood. (old reclaimed straight grain fir) I took a piece of hard wood like oak that was maybe 4 inches long and a little wider that your joint materials.  Take two regular "C" clamps and clamp the hardwood block onto the side that is receiving the screws and tightened it up, one on each end of the block.   place the block as pictured so you can aline your pieces.  I put some wood glue on the screw tip and drove the screws home. The glue acts like a lubricant and will glue any small cracks the might develop. The clamping might give you some extra strength since they are cracking out at the screw thread area and not at the pocket hole. You can then open up the Kreg supplied clamp and clamp it across the joint. (on top of the block) This brings up another point that I have seen often on home shows and by others where they are using the Kreg clamp. They turn it over in wrong direction. The large pad goes on the joint so that the large pad is on the face which is also the same location of the direction you are running the screws. This alone is important not only in alinement of the joint faces but also helps put pressure where the screws are entering. This is the idea of the block clamped to the joint as it is giving you more pressure on the screw receiving grains. I hope this might help you with the problem. 

I thought about it all day and my conclusion is that as long as you have the jig set up correctly for thickness of wood and drill debth then it has to be a condition in the wood.

Wayne Albers said:

Thanks, Jay for your help.  I read your post twice and I am not sure if I am misreading what you posted or if my photo is not showing what you need.  The ends of the stiles were cut off and you are looking at the end with the screws having entered from the rail on the right.  The screws entered the top one on a downward angle from the point of view of the photo.  The bottom on had the screws entering at an upward angle.  I cut both of these ends off and reused the shorter stiles on different face frames where the shorter stiles split.  I am beginning to wonder about the wood also.  I do not have a moisture tester, but am beginning to wonder if I shouldn't get one.  The wood is not quarter sawn although I have some oak that is quarter sawn for two cabinets and the island.  I will try again, but since the cabinets with the exception of the oak will be painted (my wife's choice not mine), I am considering getting some poplar to use for the stiles and conceding defeat.  That is not in my nature, but I can't delay this much longer.  Winter is just around the corner and the unheated garage is my shop.

[Wayne Albers]

I am feeling much better this evening as I have two face frames together with no split stiles.  I am cheating on the location of the pocket holes and keeping them to the inside of the face frame.  It only moves them in about 1/8 inch but it seems to make the difference.  I should also mention again that this I am using the Micro jig so the pocket holes are about the same size as the head on the pan head screws.  I hope this photo helps.

Before anyone sucks in that huge gasp, one frame is for a tall thin cabinet and the other is a short wide cabinet.  We are using a 2 inch rail at the top of the uppers so we have more room for crown moulding.  I am still so gun shy that I am running the final turn or less with one of those manual screw drivers.  I hope to get a few more done after work tomorrow night and will keep all of you up on progress.  I am still trying to decide what to use for lubricating the screws and have tried carnauba wax, commercial screw lube, and liquid soap.  The jury is still out.  I like the ease of the liquid soap, but it "stinks."  The carnauba is easy, but it also is tougher to get a little on and not too much.  The commercial stuff is hard.  I don't think I will try the toilet wax ring, but I am sure the price is right.  I have not tried, but may take a stab at the glue, but would have to figure out how to keep it from getting hard at my slow pace.

Thanks to all for the suggestions and for taking to time to help out.  It is an amazing feeling to have gotten past at least to this point the difficulties.

[Jay Boutwell]

Wayne, Your frames look fine.  I have to give you credit for sticking to the task at hand.  That tells me that you have the makings of a fine cabinet maker. 

Wayne Albers said:

I am feeling much better this evening as I have two face frames together with no split stiles.  I am cheating on the location of the pocket holes and keeping them to the inside of the face frame.  It only moves them in about 1/8 inch but it seems to make the difference.  I should also mention again that this I am using the Micro jig so the pocket holes are about the same size as the head on the pan head screws.  I hope this photo helps.

Before anyone sucks in that huge gasp, one frame is for a tall thin cabinet and the other is a short wide cabinet.  We are using a 2 inch rail at the top of the uppers so we have more room for crown moulding.  I am still so gun shy that I am running the final turn or less with one of those manual screw drivers.  I hope to get a few more done after work tomorrow night and will keep all of you up on progress.  I am still trying to decide what to use for lubricating the screws and have tried carnauba wax, commercial screw lube, and liquid soap.  The jury is still out.  I like the ease of the liquid soap, but it "stinks."  The carnauba is easy, but it also is tougher to get a little on and not too much.  The commercial stuff is hard.  I don't think I will try the toilet wax ring, but I am sure the price is right.  I have not tried, but may take a stab at the glue, but would have to figure out how to keep it from getting hard at my slow pace.

Thanks to all for the suggestions and for taking to time to help out.  It is an amazing feeling to have gotten past at least to this point the difficulties.

[don carmen]

there are a few situation where splitting is likely to occur. when you think it is likely,use an

extra long drill bit and pre drill through the pocket hole and into the stile being careful to

not go too deep.

Don.

[Ken Darga]

It's difficult, for most DYI'rs to obtain ''extra long'' drill bits, in the small sizes, 

that are needed for the pilot holes, for the small diameter screws.

[Rod Lowell]

Very nice trick.

[Brían Scott Du Bois]

One could use drill rod the same diameter as the kreg pocket drill.  Bore a hole in the end of the drill rod to accept a small twist drill the diameter of the screw tread shaft (material supporting the threads).  The small twist drill should be adjustable for depth.  A set screw would be needed to hold the twist drill and set the proper exposed length of the drill. One would place the collar on the drill rod to select the same depth that was drilled by the pocket drill (maybe a few thousands less to keep the end of the drill rod from burning the bottom of the pocket hole).  This design would be self centering and would prevent the user from drilling the pilot hole too deep.  This would also provide sufficient wood for the threads to grip and also limit binding of the screw shank as it is screwed into the wood.

I need to find an old south bend engine lathe, restore it, and I then I would be ready to make a prototype. Maybe you know someone who could build something similar to what I have outlined above.

I believe this will correct the one major problem I have experienced while using the kreg system.  The problem is not with the system.  The issue is the different grain structure of the wood (as others have mentioned).

don carmen said:

there are a few situation where splitting is likely to occur. when you think it is likely,use an

extra long drill bit and pre drill through the pocket hole and into the stile being careful to

not go too deep.

Don.

[Scott]

Wow! 10 pages of discussion and ways to address splitting ;)

Here's my input and strategies:

• Don't be running the screw in too fast - be patient and let the self-tapping / type 17 screw tip do it's job: clear the way for the threads
• Try stopping part way in and back the screw out - this clears the cuttings out of the 'auger' section of the screw, reducing the outward pressure as the screw finishes pre-drilling the rest of the hole
• Use double-auger fine thread screws - after my 3rd split on a maple project (I suspect a particularly brittle batch of wood), I ordered some of these that feature the extra space for the cuttings. These are the only screws I use on face frame corners. Custom Service Hardware.com has them.

Scott

[Colin Farrier]

I have obtained some very long 3 mm drill bits and I use these to pilot the hole in the remote piece of wood. It is important to use a depth stop in order to prevent through drilling. I prefer to pilot the hole in order to prevent stress in the remote piece of wood.

regards

Colin farrier

[Ed Rarick]

I solved my splitting by using #6 fine thread screws. I had tried everything else with no success (during winter months in Wisconsin).  Once I switched to #6 screws I have not had a single split.

[John]

Thank you Jay--very smart idea!

[don carmen]

I mentioned using a longer drill bit for predrilling some time ago to help with split prevention. I should also have mentioned keeping the stiles 1/2" longer or more (depending on the material) and trimming to size later.

I use the Kreg system fairly often for various projects with all kinds of wood and splitting has not been a particular issue.