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Debunking Pocket Screws

are you questioning if your pocket screws are strong enough should you skip the pockets and just screw is your pocket screw joinery more cracked than Windows Vista in 2007 we stick around because I have some answers to these burning pocket screw questions and more that are backed up by Cold Hard facts besides the fact that pocket screws can be hidden easily in some cases pocket screws are also supposedly stronger than simply using some construction screws from the outside the reasoning behind this is quite simple and to demonstrate I have some hilariously large screws and some illegal Canadian plastic straws the straws represent the grain or the fibers within the wood and the screws well they represent screws the fibers run along the length of the board and each fiber is relatively strong from severing in half however the bond between the fibers isn't as strong as the fibers themselves when you use a pocket screw you're supposed to drive it into the face or the the edge of a board but not the end of a board as the threads enter the grain this way the fibers wrap around the threads of the screw without severing and it creates a mechanical lock that prevents the screw from pulling out as easily when simply screwing one board to another from the outside and into the end grain of another the fibers are either being pushed apart or actually severing between each thread of the screw resulting in a much weaker connection between the screw and the wood anyways this is all in theory and I'm not the business of hypotheticals because I learn better by seeing and doing so let's give this a test shall we now like all of my joint testing this is fairly rough science and definitely not thorough enough but it does give us a decent idea since I'm taking the average of five joints per test there are other orientations that I can stress the joint in and this also doesn't account for longevity yada yada yada it's not perfect the pocket screw turns out to be over 20% stronger on average in comparison to the construction screw put in from the outside and into the end grain of the other and to compare apples to apples both screws are inch in a quarter number eight screws so it seems like yes this Theory holds true that pocket screws are in fact stronger but when screwing from the outside in you have the opportunity to use a much longer screw and typically with 3/4 in material like I'm using here I would at minimum use an inch and a half screw so how about we exagger at it more and see if there's anything to be gained from using a 2-in screw by the way I'm not using any glue on these tests because each joint would have the exact same amount of glue on it so I'm eliminating a variable by not including it but don't worry I have some burning questions about the effectiveness of pocket screws and glue that I want to answer later anyways back to the 2-in screw which scored a staggering two times stronger than the pocket screw and that is a considerable difference so what does all this mean in cases where where the outside of the joint does matter then pocket screws still make sense because they truly do excel in the scenario where you don't want to see any Fastener from the outside there are options to hide regular screws like making or buying hardwood plugs but this option is obviously not invisible the main point that I'm trying to get across is that I see a lot of people on social media use pocket screws in situations where construction screws from the outside won't actually be seen in the end it's clear that longer Construction screws are stronger than pocket screws and are quite obviously faster too so stop making life harder and simply screw it together when the situation is right this is all fine and dandy when it comes to solid wood but when it comes to plywood does this still hold true you see plywood is made up of layers of thin wood veneers and the grain Direction alternates 90° on each layer to create a more stable product from the pocket screws perspective the grain of the mating piece hasn't really changed much since it's all still face screen again but when using a regular construction screw driving it into the edge of plywood it's no longer just end grain like in solidwood but now it's kind of half end grain and half face grain does this mean that the regular screw of the same size might actually be stronger than a pocket screw just like the solidwood samples the core of the plywood I used was pop and they were all the exact same size with the exact same screw spacing immediately the first thing I noticed was how much more consistent the results were in comparison to the solid wood samples which definitely had a higher deviation since plywood is a man-made product it's no surprise that the results are much more uniform the engine of quarter pocket screw took almost exactly the same amount of force on average to break in the plywood as it did in the solidwood which is to be expected the inine quarter construction screw on the other hand was over 30% stronger in the plywood as it was in the solidwood and over 5% stronger in the same size pocket screw the 2-in construction screw on the other hand scored very similarly in plywood as it did in solid wood and I think it's because it was the head of the screw that failed rather than the threads in The Mating piece so even more so than solid wood in plywood it makes more sense to use longer construction screws from the outside rather than pocket screws when you don't need a hidden Fastener it's also quite common to use pocket screws to construct boxes which can be for drawers or cabinets or maybe cases but when making a drawer box you would typically place the pocket screws on the outside where they'll eventually be hidden by a drawer front good job this is the correct orientation for a pocket screw when screwing two boards together like this however sometimes you might find yourself in a pickle or placing the pocket screws on the outside of a case or a cabinet might be very unsightly in the end so you consider the ramifications of putting the pocket holes on the inside of the corner where you should shouldn't will it explode unsurprisingly the correct way is indeed a lot stronger 65% stronger in fact so this is definitely a no no if you can help it if having pocket screws or construction screws on the outside isn't going to work aesthetically then you'll have to look into other joinery options luckily for you I have a whole video on testing these types of joints and you can go watch it after you watch this one to the very and I'll know if you don't hey it's now winter time and our shops are getting kind of cold so if you want to focus on doing your best Woodwork and not your numb fingertips then perhaps it's time to upgrade your heater to the dro wall hung smart electric space heater now I already have a Minit heat pump in my shop but they're at least 15 times the cost of the drio electric space heater mini splits are complicated to 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