I watch a lot of videos and I've seen this matter discussed dozens of times, even a few visual representations. This was the best, and showed the proper way to correct it too.
Well done. Something that most of us "know", but you laid it out in a way that is difficult to ignore in the future. This approach eliminates the need for cauls 75% of the time. Thank you for illustrating this in a simple way!
Wow! I have certainly been guilty of "Cranking, and Cranking" the clamps until my arms hurt. You just blew my mind Jason. I feel like i just turned the corner on my woodworking skill set. Thank you for sharing this information.
One very important thing I would make sure people do with this method, is not just pay attention to the straightedge going flat, but also that you still have the seams together, and not opening the clamp so far that the seams are coming apart.
This is an excellent video to explain how to do this. This is exactly what I do and I have had the hardest time explaining this to people who have worked for me through the years. Well done! Thank you and keep it up.
Thanks Jason! I used this technique yesterday during a glue-up and was surprised how cupped my panel was when I initially put the straight edge down. Saved me lots of sanding! Thanks again.
This may be the best woodworking video I've seen in a long time. I've struggled with flat panel glue ups and it was likely caused by overtightening. Thank you for this masterfully explained process. You just gained a subscriber.
Love this process glad I saw this right before I'm about to glue up a table.. wood whisperer did a great analysis about parallel clamps and mentioned how they are not the best for glue ups on panels due to bar flexing causing a bow. That was a good visual representation! I'll use a mix of parallel and pipe clamps and use this technique for sure
Pipe clamps apply more pressure than a parallel clamp however they will also bow. Alternate top and bottom with whatever clamp you decide to use and check for flat with a straight edge like Jason says.
Thank you Sir, your comments and the cadence of your delivery are spot on. There was a time when we had to build a clamp rack for a glue up and close the joints flatten the work with the wedges in the rack system. You hit the method of operation right on. Love the wood grain!
A master class in an essential wood working skill- flat panel glue ups! Great video. As I watched your video I was remembering the evolution of this glue up process in our own shop. Currently, we do it exactly as shown - in every detail. But, we have had employees that swore by using cauls and cranking the clamps to the breaking point. In fact, one fella did successfully prove his strength by breaking a pipe clamp! We had to wonder if there was any glue left in the joint!
Super helpful, Jason. I am in the middle of building 2 desks for each of my sons and the first turned out not so flat. Will incorporate these tips on the next one! Thanks!
I’ve not watched your channel before. I thoroughly enjoyed this tutorial. Well spoken and well thought out. From my personal experience I like to tap the boards with a block and a no bounce mallet as they are drawing up and I feel that the gentle shock helps the biscuits get seated all the way. Nice job!
This is an excellent video in the sence that it reveals that pressure and anti-pressure may be used to correct a number of combined surfaces. Purely brilliant. Thank you for showing to us. I would be very interested to see the final product (if possible). Thanks again.
I like it. Back in the 70's and 80's [yes, yes, codger comments coming...] I made NACA section wooden daggerboards, keels, and rudders for racing sailboats from 1' x 3' x 1 to 12' x 4' x 4", as well as laminating other boat bits. They had to resist warping, cupping, or other changes in shape over time, so they had to be laminated. Here's how I did it: Choose the widest, straightest, minimal figured, minimal runout boards, quartersawn if available, but there are workarounds for flatsawn. Joint and Thickness plane to uniform size. Match the full planks for grain runout and position, and mark the ends with a code like this: starting at 3/4", every ~1 1/2" with a number and an arrow pointing up. Rip them down to 1 1/2" or thereabouts, depending on efficient use of plank width. Lay them out in numerical order with the arrows alternating up and down by rolling over every other piece 180 degrees That cancels out the internal forces. Cut spline slots with a router and flycutter bit that cuts a 1/2" deep slot, and cut the length of the piece, half deep climbing cut followed by a full cut the other way, cheaper and faster than biscuits or dominos. Make splines of similar wood, high runout a bonus, or endgrain if you have the time. Glue up as Bent does, he just taught me something. Of course I used epoxy, you use what you like. If it's a foil you're making, then markup and shape to section. Mine never warped
Truly amazing, who would have thought that would give you a perfect surface "Obviously with machined surfaces before hand" But a brilliant piece of advice. Thank you for sharing it with us.
This technique was very old when I trained 55 years ago. It is a good method but hardly qualifies as genius though many handymen on utube seem consider themselves so. Thank you.
I am surprised people don't already do that. This is also a common mistake with shaker doors. When clamping the edge it can cause the edges of a door to bow up or down if over tighten. Great demonstration.
Great lesson. I knew that just joining the edges is enough, but I thought the way to ensure flatness was to use cauls. That may sometimes matter, but to know that you can achieve that just through careful side clamp pressure makes this much simpler. Thanks, Jason!
Perfect video - thank you... I can't wait to try all of this out on my next panel glue up, particularly the genius trick! And how have only 2% of views liked this video?? How could you watch this and not like it??!
Probably one of the most useful trick I have ever heard. I happened to glue up a panel a couple weeks ago and guess what, it's not perfectly flat. Yet I saw it during the glueing process and I thought I could get rid of those defaults by tapping down with my hammer. But no. The panel is still not flat. If only I'd known this trick before. Anyway I will have some more panels to make pretty soon and I'm sure I will think of you. Thank you for sharing this wonderful trick.
You are awesome. I made that overclamp mistake and saw it cup and freaked out. I used 1/2 dowels on 2x4 table top about 70 dowels over 2 weeks a few at a time. It was exhausting. Thanks so much for your clear explanation.
very nice methodical work all the way through, and excellent the way you crank up the pressure and then back it off just so, and achieve flatness caul-free by adjusting the relative tension of top and bottom clamps. it's all based on a clear understanding of the materials and forces involved. i have one observation. i dont know how long those boards have been in your shop or when/where they were jointed and planed, but for boards like this i am not going to rely on the rough end dressing from the yard. since i'm probably going to keep boards like this in my shop for at least a couple weeks to give them time to adjust to temp-humidity, first thing i'm gonna do is trim the ends 90 degrees with a finishing cross-cut blade, and then i'm gonna seal those glass-smooth ends. i use my own boiled linseed oil/beeswax mix, but of course you can use anything that seals including spray paint and maybe even masking tape. point is to minimize surface area and block moisture transfer through the ends of the boards, forcing the boards to release (or absorb) moisture much more slowly, resulting in better stability while it's in the shop
Well said. And absolutely the edge prep is key to a successful panel/tabletop glue-up. But like you said, that's a different video. For me, I like to incorporate a spring joint. Especially in a panel or top where using Dominos, biscuits or dowels is not possible or practical. Find that it helps with flushing up the edges.
Wow!!! Finally! Thank you so much. I am definitely guilty of over-tightening the clamps on my panel glue-ups. Now I understand why I have had so much trouble getting flat panels. Definitely learned something here. Hopefully my next dining room table will be easier to get to flat after glue-up. :)
A great practical and actionable video. Thanks. IIRC you once mentioned you joint boards with a track saw. It would be great if you could show us how you go about that.
Good job. It’s not a secret between quality woodworkers but it’s important to talk techniques. I also like the alternating above below clamping. BTW I have watched your videos before purchasing some tools and found your reviews a valuable resource.
Very nicely explained and straightforward - thank you. I have 10' long x 2" thick walnut planks in my basement, that has air dried for the last 5 years. This will be first dining room table - if all goes well.
EPIC! What an awesome video! Thank you for these tips...just blew my mind! Hey I just wanted to say thank for your service to our country! I am Air Force veteran and would like to say hello from Crossville, TN! If you are ever down my way look me up I'll take ya out for supper! God bless you and your family!
I have never had someone explain this in such detail and so easy to understand. Thank you so much. I believe I have been tightening all my clamps wayyy too much after seeing this
I have a tip, instead of using a straight edge just use your clamp bars as a straight edge so once your clamp is sitting perfectly flat on your glue up you have a perfect flat glue up! Just make sure your clamps are perfectly straight, anyway good channel and new subscription for me! 😉
Awesome! I have learned that overtightening clamps is not helpful but you just solidified that theory! I have used cauls in some cases which helps the ends but still at times have issues with the center areas but I think I know why now and how to address it. Will it work as well without biscuits? Thanks for all your straightforward videos!
I love your videos man and I've watched a bunch of them. They are informative and to the point. I appreciate the seriousness in which you proffer your craft and experience. Those pretty boy, sophomoric comedy, hair music woodworking videos some of the other guys make are okay, you just have to weed through the BS. So, thanks! Great job!
About keeping glue off the parallel clamp: I tear strips of wax paper and wrap them around the bar at approximately the location where joints (and glue) will be. I use button magnets to hold the wax paper in place, which are easier to adjust than tape, and hold better.
Thank you for making the effort to be so thorough in teaching great woodworking techniques. This video is so helpful, as I've experienced all the hurdles that you have shown us how to avoid. Best to you, my friend!
Nice and useful demonstration ! Thanks a lot, because I'm one of those "overtighting" guy, thinking that dead cranked clamps was the best method… I'll sure test your tip for my next project ! Best regards from France, one more follower here !
Thank U! I use same technic when make wide table tops, 20inch+20inch. It really helps, when U need to glue up 2 table tops which arw already finish planned
Thanks for this great information and this is a good professional presentation! Keep this wonderful videos coming and thanks for sharing a professional wealth of knowledge! God bless you and your family!
Great demonstration. I have to warn for the statement at the beginning of the video. Although it is not directly related to what you show here. "The edges have to be perfectly square or at least alternating. So if one is 89 degrees the next one should be 91 degrees". While this is mathematically correct, in my experience even the slightest deviation from square causes the boards to slip when glue is applied and the clamps are tightened. When making a test assembly and the joints are still dry it is not a problem, when glue applied it is not a problem, but when the clamps are tight and it is too late it IS a problem. Even when a spline or dowels are used for alignment. The clamping force and the slipperyness of the glue causes boards to misalign. Edges have to be square. Perfect squareness is impossible of course, but should nevertheless be aimed for with more accuracy then a degree.
This is a great tip, Jason~! I'm definitely guilty of using a gorilla grip when clamping panels up. Sad part is that I have a "pricy red" straight-edge hanging on my tool wall that collects dust more than it should. Well, no more...or at least no more when there's a panel glue-up to be done. Thanks for sharing this~!
Thank you so much for this! Your explanation was superb, and your demonstration brought it home. Its incredibly simple too. I am curious, is there anything about the drying of the glue, that might re-introduce any bowing after the fact? Or does the glue dry in such a way that it won't affect that?
There are two reasons why excessive tightening of the clamps causes the distortion you show. One reason is that a greater pressure at the joints brings more into play any lack of parallelism of the two joining surfaces, the other more important reason is the non-uniformity of the wood elasticity modulus. If your jointed surfaces are exactly coplanar, the only reason for the deformation away from the plane as you tighten the clamps is the non-uniformity of the elastic properties of the wood (different grain orientation across the joining surface, etc.) These distortions, however, should largely disappear when the glue sets and the clamps are taken out. Hope this sheds some light.
I watch a lot of videos and I've seen this matter discussed dozens of times, even a few visual representations. This was the best, and showed the proper way to correct it too.
Glad you found it helpful
This is, by far, the best video on panel glue ups on youtube. Thank you.
Well done. Something that most of us "know", but you laid it out in a way that is difficult to ignore in the future. This approach eliminates the need for cauls 75% of the time. Thank you for illustrating this in a simple way!
Wow! I have certainly been guilty of "Cranking, and Cranking" the clamps until my arms hurt. You just blew my mind Jason. I feel like i just turned the corner on my woodworking skill set. Thank you for sharing this information.
Glad to help
me too
Man this would have saved me so much sanding time in the past. Thank you for this, Jason!
You’re welcome
One very important thing I would make sure people do with this method, is not just pay attention to the straightedge going flat, but also that you still have the seams together, and not opening the clamp so far that the seams are coming apart.
0
This is an excellent video to explain how to do this. This is exactly what I do and I have had the hardest time explaining this to people who have worked for me through the years. Well done! Thank you and keep it up.
I have done woodwork for about 55 years and this is one of the best advice videos and lessons I have learned, thank you.
Wow, thanks!
I second that. Superb presentation and a great technique!
I feel like I attended a master class with all your presentations. Thank you.
Thanks Jason! I used this technique yesterday during a glue-up and was surprised how cupped my panel was when I initially put the straight edge down. Saved me lots of sanding! Thanks again.
This may be the best woodworking video I've seen in a long time. I've struggled with flat panel glue ups and it was likely caused by overtightening. Thank you for this masterfully explained process. You just gained a subscriber.
Fantastic video! I tend to always over tighten, and have to spend way too long trying to sand it flat! Thank you very much
Love this process glad I saw this right before I'm about to glue up a table.. wood whisperer did a great analysis about parallel clamps and mentioned how they are not the best for glue ups on panels due to bar flexing causing a bow. That was a good visual representation! I'll use a mix of parallel and pipe clamps and use this technique for sure
Pipe clamps apply more pressure than a parallel clamp however they will also bow. Alternate top and bottom with whatever clamp you decide to use and check for flat with a straight edge like Jason says.
Thank you Sir, your comments and the cadence of your delivery are spot on. There was a time when we had to build a clamp rack for a glue up and close the joints flatten the work with the wedges in the rack system. You hit the method of operation right on. Love the wood grain!
A master class in an essential wood working skill- flat panel glue ups! Great video. As I watched your video I was remembering the evolution of this glue up process in our own shop. Currently, we do it exactly as shown - in every detail. But, we have had employees that swore by using cauls and cranking the clamps to the breaking point. In fact, one fella did successfully prove his strength by breaking a pipe clamp! We had to wonder if there was any glue left in the joint!
Super helpful, Jason. I am in the middle of building 2 desks for each of my sons and the first turned out not so flat. Will incorporate these tips on the next one! Thanks!
I’ve not watched your channel before. I thoroughly enjoyed this tutorial. Well spoken and well thought out. From my personal experience I like to tap the boards with a block and a no bounce mallet as they are drawing up and I feel that the gentle shock helps the biscuits get seated all the way. Nice job!
Thank you so much!
Perfect technique minus the Lamelos.
Another very useful and straightforward video. Thanks.
Glad it was helpful!
This is an excellent video in the sence that it reveals that pressure and anti-pressure may be used to correct a number of combined surfaces. Purely brilliant. Thank you for showing to us. I would be very interested to see the final product (if possible). Thanks again.
There will be a video on the tables
I like it.
Back in the 70's and 80's [yes, yes, codger comments coming...] I made NACA section wooden daggerboards, keels, and rudders for racing sailboats from 1' x 3' x 1 to 12' x 4' x 4", as well as laminating other boat bits. They had to resist warping, cupping, or other changes in shape over time, so they had to be laminated. Here's how I did it: Choose the widest, straightest, minimal figured, minimal runout boards, quartersawn if available, but there are workarounds for flatsawn. Joint and Thickness plane to uniform size. Match the full planks for grain runout and position, and mark the ends with a code like this: starting at 3/4", every ~1 1/2" with a number and an arrow pointing up. Rip them down to 1 1/2" or thereabouts, depending on efficient use of plank width. Lay them out in numerical order with the arrows alternating up and down by rolling over every other piece 180 degrees That cancels out the internal forces. Cut spline slots with a router and flycutter bit that cuts a 1/2" deep slot, and cut the length of the piece, half deep climbing cut followed by a full cut the other way, cheaper and faster than biscuits or dominos. Make splines of similar wood, high runout a bonus, or endgrain if you have the time.
Glue up as Bent does, he just taught me something. Of course I used epoxy, you use what you like. If it's a foil you're making, then markup and shape to section. Mine never warped
Thank you for a really clear demonstration of how clamping pressure helps determine perfect flatness in a glue-up.
Truly amazing, who would have thought that would give you a perfect surface "Obviously with machined surfaces before hand"
But a brilliant piece of advice. Thank you for sharing it with us.
This technique was very old when I trained 55 years ago. It is a good method but hardly qualifies as genius though many handymen on utube seem consider themselves so. Thank you.
I am surprised people don't already do that. This is also a common mistake with shaker doors. When clamping the edge it can cause the edges of a door to bow up or down if over tighten. Great demonstration.
Great tip!
Great lesson. I knew that just joining the edges is enough, but I thought the way to ensure flatness was to use cauls. That may sometimes matter, but to know that you can achieve that just through careful side clamp pressure makes this much simpler. Thanks, Jason!
@@mm9773 Good points.
So, how much does that biscuit drill cost? It seems dowels would work well and possibly save the additional cost of that biscuit tool.
$100 USD for a corded Ryobi to about $240 for a good cordless Dewalt, so not very expensive@@DaleLSeth
That was the best example of why you should not over tighten clamps that I have seen thus far. Thank you!
Glad it was helpful!
I knew I would never need the skills learned in wood shop in Junior High. I learn more in an hour on RUclips, than a semester of woodshop.
Thx. You just spared me the job in the future of additional clamping vertically!
Perfect video - thank you... I can't wait to try all of this out on my next panel glue up, particularly the genius trick! And how have only 2% of views liked this video?? How could you watch this and not like it??!
Probably one of the most useful trick I have ever heard. I happened to glue up a panel a couple weeks ago and guess what, it's not perfectly flat. Yet I saw it during the glueing process and I thought I could get rid of those defaults by tapping down with my hammer. But no. The panel is still not flat. If only I'd known this trick before. Anyway I will have some more panels to make pretty soon and I'm sure I will think of you. Thank you for sharing this wonderful trick.
You are awesome. I made that overclamp mistake and saw it cup and freaked out. I used 1/2 dowels on 2x4 table top about 70 dowels over 2 weeks a few at a time. It was exhausting. Thanks so much for your clear explanation.
Excellent tip! Thank you. So true, the instinctual reaction is to try and "tighten" your way out of this problem.
This video gives me a ton of confidence for my next large glue-up. Thank you!
very nice methodical work all the way through, and excellent the way you crank up the pressure and then back it off just so, and achieve flatness caul-free by adjusting the relative tension of top and bottom clamps. it's all based on a clear understanding of the materials and forces involved. i have one observation. i dont know how long those boards have been in your shop or when/where they were jointed and planed, but for boards like this i am not going to rely on the rough end dressing from the yard. since i'm probably going to keep boards like this in my shop for at least a couple weeks to give them time to adjust to temp-humidity, first thing i'm gonna do is trim the ends 90 degrees with a finishing cross-cut blade, and then i'm gonna seal those glass-smooth ends. i use my own boiled linseed oil/beeswax mix, but of course you can use anything that seals including spray paint and maybe even masking tape. point is to minimize surface area and block moisture transfer through the ends of the boards, forcing the boards to release (or absorb) moisture much more slowly, resulting in better stability while it's in the shop
Well said. And absolutely the edge prep is key to a successful panel/tabletop glue-up. But like you said, that's a different video. For me, I like to incorporate a spring joint. Especially in a panel or top where using Dominos, biscuits or dowels is not possible or practical. Find that it helps with flushing up the edges.
Well said!
Dude, super helpful and so simple. Thank you. This will make me better.
Glad it helped!
Wow!!! Finally! Thank you so much. I am definitely guilty of over-tightening the clamps on my panel glue-ups. Now I understand why I have had so much trouble getting flat panels. Definitely learned something here. Hopefully my next dining room table will be easier to get to flat after glue-up. :)
Thanks for the great video Jason! I struggle with flat panels so much!
Happy to help!
This video is valuable on the don’t overtighten clamps lesson alone. Thanks, Jason!
A great practical and actionable video. Thanks. IIRC you once mentioned you joint boards with a track saw. It would be great if you could show us how you go about that.
Great suggestion!
I have never watched a video about overtightening clamps before, and I did have the question in my mind how tight is to tight. Thank you.
Very welcome!
Thanks. Very helpful hint for the Clamp Pressure vs. Flattening. Good job.
Glad it was helpful!
Holy hell, I just made this exact mistake on a woodworking project! This is one of the most useful tips I've seen online!
Good job. It’s not a secret between quality woodworkers but it’s important to talk techniques. I also like the alternating above below clamping. BTW I have watched your videos before purchasing some tools and found your reviews a valuable resource.
I'm over so guilty of this. Thank you so much for this tutorial.
You are so welcome!
This is a good one, Jason. This is always a topic in woodworking groups that seems to be almost as misunderstood as dust collection.
Very nicely explained and straightforward - thank you. I have 10' long x 2" thick walnut planks in my basement, that has air dried for the last 5 years. This will be first dining room table - if all goes well.
Great video! I learned something else today. Never too old to learn ;) Thanks!
Glad to hear it!
Excellent information, loved the straight edge portion!!! Thanks for sharing.
EPIC! What an awesome video! Thank you for these tips...just blew my mind! Hey I just wanted to say thank for your service to our country! I am Air Force veteran and would like to say hello from Crossville, TN! If you are ever down my way look me up I'll take ya out for supper! God bless you and your family!
Thank you as well 👊🏼
I have never had someone explain this in such detail and so easy to understand. Thank you so much. I believe I have been tightening all my clamps wayyy too much after seeing this
That is the best tip I have gotten in years!!! Thanks
Great to hear!
Great way to ensure you're flat and clamped as you should be. This idea goes into my toolbox; thank you.
Glad to help
Excellent! I've been an aggressive amateur woodworker, but this problem has always haunted me. Thanks, and subscribed!
👍👍👍👍 Giving many more Thumbs Up Likes!!! So nice to see basic, but very misunderstood, techniques explained, and visually shown. Thanks Jason!!
Glad it was helpful!
I have a tip, instead of using a straight edge just use your clamp bars as a straight edge so once your clamp is sitting perfectly flat on your glue up you have a perfect flat glue up! Just make sure your clamps are perfectly straight, anyway good channel and new subscription for me! 😉
The least little crank of a screw will start any bar clamp bending, it is not avoidable. The stock will bend with it, if is in contact with the bar.
Awesome! I have learned that overtightening clamps is not helpful but you just solidified that theory! I have used cauls in some cases which helps the ends but still at times have issues with the center areas but I think I know why now and how to address it. Will it work as well without biscuits? Thanks for all your straightforward videos!
I love your videos man and I've watched a bunch of them. They are informative and to the point. I appreciate the seriousness in which you proffer your craft and experience. Those pretty boy, sophomoric comedy, hair music woodworking videos some of the other guys make are okay, you just have to weed through the BS. So, thanks! Great job!
Happy to hear that! Thank you
This is great info. I'm trying to get into woodworking and need to keep this in mind. Thank you.
About keeping glue off the parallel clamp:
I tear strips of wax paper and wrap them around the bar at approximately the location where joints (and glue) will be. I use button magnets to hold the wax paper in place, which are easier to adjust than tape, and hold better.
Thank you for making the effort to be so thorough in teaching great woodworking techniques. This video is so helpful, as I've experienced all the hurdles that you have shown us how to avoid. Best to you, my friend!
Nice and useful demonstration ! Thanks a lot, because I'm one of those "overtighting" guy, thinking that dead cranked clamps was the best method…
I'll sure test your tip for my next project ! Best regards from France, one more follower here !
The straight edge idea is awesome. Thanks for sharing!
Wow! I struggle every time I do these but no longer. Your videos are great thanks
Glad you like them!
Nicely done. Logical, clean and neat.
Great video. I`m just about to glue up an 8 foot table top and this video gave some great info that should help. Thanks
Thank U! I use same technic when make wide table tops, 20inch+20inch. It really helps, when U need to glue up 2 table tops which arw already finish planned
Wow, learning something new every time you post - thanks for sharing!
Glad to hear it!
Great video. Just ordered my straight edge. Thanks
Glad you enjoyed it
Great video and so many great and useful tips thanks for sharing
Glad it was helpful!
Thanks for this great information and this is a good professional presentation! Keep this wonderful videos coming and thanks for sharing a professional wealth of knowledge! God bless you and your family!
Glad you enjoyed it!
I’ve learned SO much watching your videos. Thanks!
Happy to help!
Great video, simple and well explained, you've earned a subscription. Thank you
Good Stuff Brother... Youve a concise manner of instruction.. Comes with the territory given your former occupation.. Thank you for your service.
Thanks! I appreciate it
Great video! I'm making an elm table, and will use all of this advice. Thanks.
Glad it was helpful!
This is a great tip. Thank you. I use cauls in my glue-ups, but I will definitely try this.
Glad it was helpful!
I actually noticed this phenomenon this weekend on a glue-up I’m doing. I noticed that loosening the clamp caused it lay flat. 👍🏻
This is a great hack for flat panels. Thanks for sharing
You are so welcome!
Thank you for this! Excellent
Very good lesson and well presented.
Glad you liked it!
This was such an informative video. Thank you so much for doing these videos.
You are so welcome!
Very simple yet very helpful. Thanks!
Glad it was helpful!
Great video. Very helpful! Thank you for demonstrating this.
Glad it was helpful!
Great explanation and demonstration! Thank you so much!
You’re welcome
très bonnes infos , à retenir pour les prochains collages.
Great demonstration. I have to warn for the statement at the beginning of the video. Although it is not directly related to what you show here. "The edges have to be perfectly square or at least alternating. So if one is 89 degrees the next one should be 91 degrees". While this is mathematically correct, in my experience even the slightest deviation from square causes the boards to slip when glue is applied and the clamps are tightened. When making a test assembly and the joints are still dry it is not a problem, when glue applied it is not a problem, but when the clamps are tight and it is too late it IS a problem. Even when a spline or dowels are used for alignment. The clamping force and the slipperyness of the glue causes boards to misalign. Edges have to be square. Perfect squareness is impossible of course, but should nevertheless be aimed for with more accuracy then a degree.
This is a great tip, Jason~! I'm definitely guilty of using a gorilla grip when clamping panels up. Sad part is that I have a "pricy red" straight-edge hanging on my tool wall that collects dust more than it should. Well, no more...or at least no more when there's a panel glue-up to be done. Thanks for sharing this~!
Glad it was helpful!
great video....tape on clamps...wow...never thought of that!
Crazy good technique. Thank you.
Very welcome!
Thank you so much for this! Your explanation was superb, and your demonstration brought it home. Its incredibly simple too. I am curious, is there anything about the drying of the glue, that might re-introduce any bowing after the fact? Or does the glue dry in such a way that it won't affect that?
Absolutely brilliant video. great instruction.
Great video and tip!
Patiently waiting tor you to show the new table saw!
Next week!
So well explained!! I am definitely an overtightener! not anymore :)
Glad it was helpful!
Best panel glue up video ever, thanks a lot bro
good instruction for a fully equiped wood working shop!
Thank you for this. This happened to me on my first attempt at making a desk top.
You're welcome!
Wow! This is really helpful. Thank you so much!
I think my problems wll be sorted by this. Thank you for excellent tutorial
Glad it helped
Thanks for this lesson 👍
My pleasure!
There are two reasons why excessive tightening of the clamps causes the distortion you show. One reason is that a greater pressure at the joints brings more into play any lack of parallelism of the two joining surfaces, the other more important reason is the non-uniformity of the wood elasticity modulus. If your jointed surfaces are exactly coplanar, the only reason for the deformation away from the plane as you tighten the clamps is the non-uniformity of the elastic properties of the wood (different grain orientation across the joining surface, etc.) These distortions, however, should largely disappear when the glue sets and the clamps are taken out. Hope this sheds some light.
Thank you