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David Zaret
02-10-2021, 5:10 PM
i make almost exclusively face frame inset cabinets, and have for years - i've made a lot of face frames.... traditionally, i domino my face frames together (with 4mm dominos), and that yields great results, but it's slow and tedious, and clamping takes time. recently, i thought i would speed up my process by switching to pocket screws. i have a good flat-surface clamping setup (with the Kreg tracks and heavy clamps), and a good pocket hole machine.

yet, no matter how accurate my setup, and how much i work, in hardwoods, i get terrible results. things wander, parts split.... undoubtedly the results are better in softer woods, but still nowhere near the quality i get when i domino and clamp.

can somebody please convince me that my process and techniques are the issues, and not the fundamentals of pocket hole joinery in hardwood? how do others do this? i love the idea of it, but despite my setup and quality tooling, i still can't reliably get great joints via pocket screws.

thanks for any guidance.

--- dz

Marc Fenneuff
02-10-2021, 5:49 PM
You’ve found out that pocket screws aren’t all that quick. In fact the clamping required to make sure they don’t stray on you for the showy stuff really slows the process down. I’m usually successful but I clamp the heck out of my face frames. If I had a domino I’d probably stick with that.

Jared Sankovich
02-10-2021, 6:36 PM
Not sure what the issue is, I get very minimal shift (only if I over drive a screw with a impact) and I can't recall a split. I did get slightly more shifting occurrences before I switched to a castle machine, again usually from over torqued screws.

I've domino'd face frames before and pocket screws are easily 10x faster.

Dan Chouinard
02-10-2021, 7:26 PM
I have pocket screwed face frames together without issue for ten years in fir, pine and poplar. I have always imagined it would be a different experience with something hard like maple. I would also like to know from those with experience the best way to pocket hole hardwood.

Lee Schierer
02-10-2021, 7:29 PM
A few clarification questions:
Are you using Kreg screws? Are they hardwood screws or soft wood screws.
What hard wood is giving you issues?
How close to the ends of boards are you driving the screws?

John TenEyck
02-10-2021, 7:29 PM
How much glue are you using? Too much glue allows the parts to shift more easily. Try putting a couple of joints together with no glue. If the parts don't shift then you were using too much glue. If they do then you don't have enough down force on the parts or you are driving the screws too far. Also, make sure to use fine threaded pocket screws for hardwoods. Split parts suggests you are using the wrong type of screw or driving them too hard.

John

David Zaret
02-10-2021, 7:46 PM
guys, thanks for this, i appreciate the help and feedback. to be clear, i'm not new to pocket holes, but i am "new" to them (as a primary approach) for hardwood face frames. i am using a Kreg pneumatic machine to bore the holes. i am using 1 1/4" pocket hole screws, purchased from richelieu, fine thread. i fully understand and appreciate the importance of using the right screws.

john, your thoughts on the glue are interesting and i'll try that. the issues i'm having are in hard maple - in cherry, walnut, poplar... no issues. mixed results in oak. lee, yes, i'm doing rails to stiles, and yes, the holes are very close to the edge. i'm compressing the heck out of the joint with my clamps, so my thought was that the compression would keep the wood from splitting, given that the screws are self-drilling.

yet, i struggle.

here's my assembly/clamping table, an MFT i dedicated to this purpose and for one of the vacsys units. note the flip-up outriggers to support large face frames - that works quite well.

451844451843

Michael W. Clark
02-10-2021, 8:15 PM
What are you using to drive the screws? I use a drill and set the torque low. I had splitting issues with hard maple. I spin the screw freely with the drill without much pressure so it predrills more instead of the screw grabbing and feeding.

David Zaret
02-10-2021, 8:18 PM
milwaukee impact driver, set on low speed. maybe i need to drink less coffee?




What are you using to drive the screws? I use a drill and set the torque low. I had splitting issues with hard maple. I spin the screw freely with the drill without much pressure so it predrills more instead of the screw grabbing and feeding.

George Bokros
02-10-2021, 8:21 PM
Try putting wax on the screw threads. The screws drive with less torque. I use wax on all screws not just pocket hole screws. Helps keep screws from breaking and tearing up the screw head.

Impact driver applys more torque than is necessary. I use my 3/8 cordless drill set about mid point.

Jim Becker
02-10-2021, 8:24 PM
Pretty much every face frame I've made since the first ones for my kitchen renovation in 2003 has been done using pocket screws. Clamping is critical and as someone mentioned, not overdriving the fastener is also important. If I were going to be doing this a lot, I'd also opt for a pocket hole machine that reduces the angle of the screws as that angle is what sometimes pulls things out of whack if the clamping doesn't hold.

David Zaret
02-10-2021, 8:24 PM
good idea george, i can definitely try that... thanks.

David Zaret
02-10-2021, 8:26 PM
Pretty much every face frame I've made since the first ones for my kitchen renovation in 2003 has been done using pocket screws. Clamping is critical and as someone mentioned, not overdriving the fastener is also important. If I were going to be doing this a lot, I'd also opt for a pocket hole machine that reduces the angle of the screws as that angle is what sometimes pulls things out of whack if the clamping doesn't hold.

maybe i have the wrong machine? it was expensive - like $4k or so - it's the kreg pneumatic, and seems to work really well....

Michael W. Clark
02-10-2021, 8:26 PM
I use a Bosch 10.8V drill, torque value of “10” which I think is about 2/3? Max torque setting.

Letting the screws predrill more before they start driving helped me quite a bit.

I have a Kreg K3 jig, and use the closest 2 holes on 1-1/4 face frames. Frames 1-1/2 are better.

Jim Becker
02-10-2021, 8:29 PM
I believe the Castle pocket cutters have a very low angle compared to drill based systems. But yes, the Kreg is a good system...you just have to have things clamped down really well. Perhaps your pneumatic clamps need adjusting?

David Zaret
02-10-2021, 8:42 PM
I believe the Castle pocket cutters have a very low angle compared to drill based systems. But yes, the Kreg is a good system...you just have to have things clamped down really well. Perhaps your pneumatic clamps need adjusting?

jim, funny you say that. i bought this machine at IWF a few years back, and when i was shopping for one, we went to the castle booth, knowing that the drilling angle is preferred. after 20 minutes of hanging out in the booth, right by the $6k machine i was thinking of buying, and getting blown off to a degree that's nearly shocking at IWF. so i left. Kreg seemed high quality, and they paid attention to me.

anyway -- maybe i need to check the drill depth on the machine, and my air pressures.

thanks again.

Bruce Wrenn
02-10-2021, 8:43 PM
Let the screws do the work Don't try to force them in. When screw exits first piece, it has to start a new hole in second, but it's advancing forward with every turn. A thinner shank screw may help as it will be looser on hole in first piece. Are you sure you have drill bit set to correct depth? Bit should just protrude through first piece.

Kevin Jenness
02-10-2021, 8:45 PM
I have found I get the best results by clamping endways as well as down across the joint.

Splitting in maple or harder woods can be eliminated by predrilling with a 1/8" aircraft drill.

I use a Castle type machine and the lower angle definitely helps with alignment, but I think you will find that clamping in both directions will work with the 10 degree Kreg angle. The key is to keep the parts from moving as the screws are driven. You might experiment with the drilling depth or with another brand of screw. I never really liked the Kreg setup which doesn't drill the pilot hole all the way through the rail, leaving it to the screw to complete that step. I think the screw may be pushing the pieces apart with that last bit of swarf.

David Zaret
02-10-2021, 8:45 PM
bruce i'll definitely check the drill depth. i'm using the #7 fine threads, i believe, not the #8. i'll check my technique to ensure i'm not pushing too hard...

John TenEyck
02-10-2021, 10:36 PM
Let the screws do the work Don't try to force them in. When screw exits first piece, it has to start a new hole in second, but it's advancing forward with every turn. A thinner shank screw may help as it will be looser on hole in first piece. Are you sure you have drill bit set to correct depth? Bit should just protrude through first piece.

Pocket holes with the Kreg jig do NOT break through the drilled piece (rail, in this case). If they do, it's not set up properly.

John

Thomas McCurnin
02-11-2021, 1:19 AM
+1 for Kreig, but I use a dedicated Kreig clamping jig and their screws. I pay close attention to the length of the screws and the stock and run 1-2 practice pieces to see if I get any blowout. Usually with properly sized stock and Kreig screws, and not going whole hog on the driver drill, I get good, quick results.

Rick Potter
02-11-2021, 2:28 AM
I have only built two kitchens with pocket screws, but seem to have good luck. All my cabinets have been red oak. I can suggest the following which works for me, and much has already been mentioned.

I have used an original Kreg jig for the first kitchen, and a Kreg electric foreman for the second. Only Kreg 1 1/4" fine thread, washer head screws.

1: Plane and sand all members to the same thickness.

2: Light glue, and clamp down to a table. I only do one joint at a time, and clamp it tight.

3: Be careful with drill depth (especially with the Foreman, as it's easy to set it too deep). The hole should not go through the end of the drilled members, and when you drive the screw through the end, it should end up pretty much in the middle.

4: Do not drive it too deep, an impact driver can easily drive it too deep, especially if you are using the regular head screws. I always use washer head for that reason. Of course you never use flat head screws which will guarantee splits. I drive mine in till it seats well, then finish it by hand with a t/handle screwdriver. This way I can feel when it is over tightened. Remember, the deeper you drill the further into the mating piece it goes, and the lower the entry point into the mating piece is.

I have been meaning to make a Kreg table, but so far I am using a sheet of melamine with two strips at a right angle screwed on to square things up. I just lay it on the workbench when needed.

Hope this helps.

Dan Chouinard
02-11-2021, 5:58 AM
I started pocket hole joinery with the manual kreg jig. I quickly learned that the vise grip type of clamp supplied by kreg is not helpful. I clamp to a table with a bessey kbody and twist the knob on the clamp as hard i can. Great results in softer wood but have yet to try in maple but we are considering using maple in future paint grade cabinet projects. The part that is counter intuitive for me is the bit about not drilling pilot hole all the way thru. I learned decades ago that if a pilot hole is actually thru the wood and is larger than the screw thread and let the screw head do the holding you get much better results.

Eric Schmid
02-11-2021, 10:36 AM
What Kevin is saying has been my experience. After some difficult Birch, I reworked my setup for certain woods.

For clamping, I use a Kreg right angle clamp. Push the two pieces firmly on the table and set the right angle clamp. Then for good measure I’ll clamp the faces of the two pieces down to the bench or table top. Once the first screw is in, one clamp across the face of both pieces should be sufficient. The standard double round pad Kreg clamps work well for this.

Before driving the screw try an aircraft bit as Kevin suggests. Take some care to find the angle initially. I think I cut a small angled block. You don’t need to drill the full depth of the screw in the mating piece. About half that distance should stop the splitting.

I guess I use pocket screws primarily as clamps, just ones that stay in place. The advantage may not be speed in assembly, but rather speed in moving the project along. I don’t need to wait for glue to cure and can move on to final assembly of the cabinet.

Jim Dwight
02-11-2021, 12:02 PM
I don't think you have room but in cabinets I find that a domino or biscuit in the same joint as the pocket screw works well to reduce or eliminate shifting. Even a dowel would make a big difference, I think, if there is room. Pocket screw could still clamp the joint.

Prashun Patel
02-11-2021, 12:15 PM
I have similar clamping issues in hard, hardwoods like maple and oak too. The issue I believe is the self drilling tip. That has to do a lot of work on harder woods. Hard woods really need to be pre-drilled for me to be consistently successful with screws; this makes pocket holes less appealing here.

So, my advice is use the pocket jig for the softer woods and dominos for the harder ones. For my money, it's not just about the speed, but the effort required to get that speed. Dominos, while requiring double the cuts of pocket screws, make the mating cuts a snap because they don't have to align perfectly if you use the sloppy switch.

Jared Sankovich
02-11-2021, 1:35 PM
Castle pocket, but those are a kitchens worth (82 panels) of soft maple face frames. The top pocket centers are about 1/2" from the edge.

No splits, kreg 1.5" screws (7/8 thread engagement) pockets are set for the pilot hole to break through at the exact centerline of the 1" stock.
451879

Worst shift is about .004 to .006, on some but I intentionally over drove to ensure a gap free bead miter.
451882

Clamp setup
451883

ChrisA Edwards
02-11-2021, 2:36 PM
Castle pocket,

Are these with the Castle 110 machine or one of the more expensive ones?

Jared Sankovich
02-11-2021, 2:49 PM
Tsm-10 (porter cable licensed version) generally the same as the current Tsm-12 model. Though I added a pneumatic clamp and foot switch.

David Zaret
02-11-2021, 5:56 PM
i think the domino+pocket screw for clamping is the answer. that's what i was doing prior to my theoretical change to gain speed and efficiency, but i think i'll go back to that with hardwoods.

i really like the profile and angle of the castle holes more than the kreg. wish they had cared enough at IWF to take my money.

thanks for all the help and feedback - i'll drop a wax stick in with the screws and use it, and i won't drive them as hard. good ideas.

--- dz

Tom Willoughby
02-12-2021, 10:29 AM
One of those specialty clamps that fits into the pocket hole (https://www.rockler.com/kreg-automaxx-right-angle-pocket-hole-clamp?country=US&sid=V91041&promo=shopping&utm_source=google&utm_medium=cpc&utm_term=&utm_content=&utm_campaign=PL&tid=pla&utm_source=bing&utm_medium=cpc&utm_campaign=(NX)_Shopping_-_A&msclkid=cda821b2c6281c81660c41945b2d2106) keeps the pieces from coming apart while driving the screw. Of course, you need at least two holes so that you can screw one while clamping with the other.