Pinch dogs - Spring board edges or no?

[Tyler Bancroft]

Getting ready to use pinch dogs for the first time to help glue up a tabletop. I've seen some people recommend a slightly sprung edge joint (with a convexity in the middle, rather than the usual hollow in the middle for a sprung joint) to help get a tight joint. Anyone have an opinion on whether to spring/not spring edge joints when using pinch dogs? I do realize that a good glue joint is (at least) as sturdy as the wood itself, but I'm not wild about having the ends of the joint in permanent tension for something I'm hoping will last for decades.

[Will Blick]

Hi Tyler...
what thickness wood? What lengths?
How many boards in the panel glue up?
will use clamps also, or just pinch dogs?

Much of this depends on how straight your edges are.
If you make your edges on a well tuned jointer, or a good track saw / Table saw...
first dry fit the edges together, if the joints are seamless to your eye with no pressure
well, you don't mean much at all... just glue and rub together, lay on flat surface.
if you see gaps, now you need clamp pressure of some type.
I personally am not a fan of spring joints...

[Mel Fulks]

I've always used sprung joints ,on thousands of panels. Ends touching . Slight opening with hard woods . Little more
with soft woods . The joints that open are on glue ups, that start with open ends. Even perfectly straight jointing can
become slightly open over night before being glued. It's a old ,good practice that is just a little more work and provides
long term benefit.

[Mel Fulks]

One place I worked always had panel ends that opened on exterior panels....but just sometimes on interior panels.
Foreman said it couldn't be prevented . I stopped all of it.

[Tyler Bancroft]

Hi Will,
3/4 cherry. About 80" long, about 12" wide. My current thinking is a non-sprung joint (I'll edge-joint pairs of boards with a plane for a good match) with pinch dogs on the ends and some clamps throughout the middle segment for extra pressure, given the length. That being said, I'm curious whether people tend to use pinch dogs one way or another.
Cheers
Tyler

[Mel Fulks]

I certainly agree with Will that short pieces can be "rubbed" together and left to dry.

[Will Blick]

I should have mentioned, if your dry fit is seamless, don't let the boards sit over night before gluing up... as u know, wood can move quickly if conditions are right.
Mel, if your boards are jointed well and close to seamless on a dry fit, in which mild clamp pressure would overcome, why spring them? I am interesting in knowing what I might be missing.
I often wondered if the spring joint was used long ago before modern tools, whereas today its much easier to get a straight edge. If getting a straight edge was unpredictable, it was better to purposely spring the boards so all the ends would surely have no gaps.
I have not visited this topic in awhile, and it seems this thread somewhat confirms my suspicions...
https://sawmillcreek.org/showthread.php?184817-Who-uses-a-sprung-joint-and-why
Like others in this link, I never sprung a joint and never had a failure, so in my case, if it aint broke...

[Tyler Bancroft]

I should have mentioned, if your dry fit is seamless, don't let the boards sit over night before gluing up... as u know, wood can move quickly if conditions are right.
Mel, if your boards are jointed well and close to seamless on a dry fit, in which mild clamp pressure would overcome, why spring them? I am interesting in knowing what I might be missing.
I often wondered if the spring joint was used long ago before modern tools, whereas today its much easier to get a straight edge. If getting a straight edge was unpredictable, it was better to purposely spring the boards so all the ends would surely have no gaps.
I have not visited this topic in awhile, and it seems this thread somewhat confirms my suspicions...
https://sawmillcreek.org/showthread.php?184817-Who-uses-a-sprung-joint-and-why
Like others in this link, I never sprung a joint and never had a failure, so in my case, if it aint broke...

What I've read is that the sprung joint was previously used in part because of the of clamps, not because of edge jointing issues - as long as you can plane both edges at the same time, it's not too hard to get a good fit. But a sprung joint reduces the number of clamps you need for glueup.

[Mel Fulks]

The argument for sprung joints is the ends of the boards in a glue up are where moisture will be lost. If we went to a lot
of commercial shops and tested the fit of jointed parts ,we would find many more open ends than ,than good fits. Just a
tiny bit of wear to jointer knives will cause the "climbing" that makes sprung joints. For the unskilled trying to end up
with straight stock that is a problem. The standard default setting for jointers in commercial shops is a slightly too low
out feed table. That asures the unskilled will not have to deal with climbing when jointing a board with one sawn edge.
But there is no real substitute for knowing how to adjust a machine for the task.

[Will Blick]

Whoa! Details matter a lot!
12" wide is considered WIDE! 6-8" is more commonplace.
AT this width and a hardwood, it becomes more difficult to overcome gaps, whether intentional or not.
80" is consider LONG, not super long, but long enough to be CAUTIOUS in a home shop.
How will u get your edges straight?

Your thought of hand planing mating pairs of boards is good for complimentary angles, but it is counterproductive for straightness . Lets assume u did NOT want a spring joint...and by hand planning your center of each board is lower than the ends. When you mate the boards, you have a center gap. IN the old days, that was the premise of the spring joint, i.e. done intentionally, to overcome the inability to get boards straight enough. So this allows for a flush joint with the ends always touching when done just right..in your case, a tiny spring.

I would have sufficient clamps, specially with 12" wide boards. Titebond suggests up to 250psi of pressure at the glue line. (remember, if your boards are near perfectly straight, less pressure is required) So in your case, every 4" of board length = 3 sq inches of glue surface area or 750 psi required, which is one GOOD parallel clamp (avg P clamps only deliver 500-600 psi). So considering these are 12" wide boards (harder for clamps to flex the wood), I would use clamps every 4", a LOT of clamps. If your edges are very straight, u can get away with less, u will have to judge that based on the dry fit...if dry fit looks good, prob half the clamps will be safe.

I would then be concerned with keeping the boards flush, unless your final thickness is much less than 3/4". There are ways to keep two boards flush... long bars and clamps can work if the glue up is not too wide, but 24" for two boards is pretty wide for bars, as metal bars flex too. Considering the length here, and if you are working solo, I would use dowels! Long dowels are the best IMO from preventing buckle and keeping the faces flush. Use a dowel jig that references the face of each board. Again, dowels are not required for strength, but they act as an extra set of invisible hands during the glue up to keep the boards flush.

Not to scare you, but there is a lot that can go wrong here, and u know Murphy is always watching us ! I personally would not attempt to spring 12" wide boards, tooo much stress to overcome. I would not use pinch dogs as they have such a minimal effect here, as you need a lot of pressure to assure your ends are together. Instead, rely on proper clamp pressure.

You did not mention how many boards are being glued up total. That matters too. Based on your experience, you might consider gluing them up in pairs, then joining each set of pairs, i.e. in stages. Therefore, less to control during that critical glue open time which is NOT very long.

If you ever see large factories make table tops, they get relatively straight edges, then immediately put them in a press, apply glue and pneumatic clamps apply pressure at BOTH the joint and perpendicular to the joints to keep the panel FLAT. Solo workers in a home shop, do NOT have the luxury of this level of automation, strength and force. So you must be smart about your approach.
Hope this helps

[Will Blick]

Tyler, what you read about spring joints though.... details matter.
if your boards are 12" wide, and hard cherry, this is a lot of force to overcome the gap the spring joint creates. I would suggest if you do want to spring, make it the smallest center gap possible! This will assure your ends touch and you will have enough clamp pressure to overcome the spring, while not making the joint become non flush.. more clamp pressure = more risk of non flush joint line!

Mel, your point is very valid, thx for contributing that. It will be helpful to many. In my case, my jointer is very accurate with looong beds. I can get dead straight boards (although I rarely use 80" long boards, the longer the boards, the less likely the jointer will keep them straight as the reference is the table length)...and then I check the jointed edge with 6' long Starrett straight edges to confirm straightness. Hence why I never needed to spring a joint. But for the reasons you mentioned, I can see why a slight spring can be a safer bet, overcoming errors that many will have in the edge jointing process.

This is a good example of why often, there is no SINGLE right answer for everyone, we are all working with different tools, wood types, wood size, techniques and experience levels.

[Will Blick]

One last tip...

> But a sprung joint reduces the number of clamps you need for glue-up.

BTW, nothing beats experimenting with your wood, your clamps, etc ;)
take your slightly sprung boards, no glue...pair them clamp them, see what it takes to make that joint seamless, do this BEFORE you apply glue to assure you can accomplish the seamless joint. Also, notice if that amount of pressure is making the boards non flush, cause when wet glue is applied, non flushness errors becomes 4x worse!

Also, be sure your clamps sit on a flat surface, as that will influence final flatness of the glued boards.
Keep us posted, good luck!

[Tyler Bancroft]

12" (actually, one is more like 13") rough-cut cherry is definitely fun to prep by hand. There's a lot of planing to do, but it's like planing butter, and the scent is wonderful. (It's almost pure heartwood, too, so I am slightly anxious about screwing up, because boards like these don't come along every day. I've been sitting on them for a couple of years.). Three boards total, so I only have to get two sets of edge pairs matched.

The plan for straight edges is a jointer plane, a long straightedge, and patience. Straighten edges first, and then plane pairs of edges if necessary. Lacking access to an industrial-sized jointer (and lacking the money and space to buy one), I'm doing things the traditional way.

I'm hoping the pinch dogs help with keeping the boards flush, but I expect some remedial planing after glueup will be necessary. I have an 1890s-era Stanley no. 8 that was made for situations like this...

[Will Blick]

this should be fun...
let us know how it worked out and what went well, and what was challenging...
3 boards will make this a lot easier...
You will surely get a good physical workout doing all this neander! Kudos to you!
I love using hand planes, have a LOT of them. I would struggle to get 80" long boards x 12" FLAT and of equal thickness! That is quite the Neander task!
as u correctly point out, a LOT of patience is the most important ingredient!

[Mel Fulks]

Some good open mindedness in this thread! But fun anyway !! On jointers with a wheel out feed adjustment, instead of
a "stick shift ", you can measure how much a bit of turning elevates out feed. Then file some marks on the wheel and
add a sheet metal pointer to jointer . Then you can easily raise for sprung joints ,and easily reset. The shorter the stock
the higher the table. On short pieces you sometimes need to bang the lead corner of stock to clear the raised table, it's
better to use longer stock ,then cut after the jointing and gluing.
On the old beefy jointers ,marks
about 3/8ths apart will move table up couple thou.

[Tyler Bancroft]

this should be fun...
let us know how it worked out and what went well, and what was challenging...
3 boards will make this a lot easier...
You will surely get a good physical workout doing all this neander! Kudos to you!
I love using hand planes, have a LOT of them. I would struggle to get 80" long boards x 12" FLAT and of equal thickness! That is quite the Neander task!
as u correctly point out, a LOT of patience is the most important ingredient!

With COVID, I can't go out as much, so I have to get my exercise inside. And I have a LV scrub plane, which saves a lot of time on the early flattening, but it's definitely going to be a longish project. But we'll see just how flat I can get them...I haven't worked on anything quite this large before. (I've done ~12" wide maple, but shorter, and it definitely moves over time.) I do wonder a bit just how flat your average large wood tabletop stays over time. If it's assembled with wide boards, surely it's going to display a fair bit of seasonal movement? I've never had the opportunity to wander into an antique furniture store with a straightedge....

[Jim Koepke]

I'm hoping the pinch dogs help with keeping the boards flush, but I expect some remedial planing after glueup will be necessary. I have an 1890s-era Stanley no. 8 that was made for situations like this...

You will likely have better results with a few cauls to hold your boards flush.

If a pinch dog isn't perfectly aligned, it may be the cause of the boards becoming misaligned.

jtk

[Will Blick]

> Some good open mindedness in this thread!

Why is this always not ALWAYS the case? Forums have such potential, but as seen in a recent post I made on product review of a honing guide, sometimes the comments are so unjust, off topic, offensive, etc. Glad to get back to a normal thread where people helping each other! Thx for the tip Mel on the adjustments...


> But we'll see just how flat I can get them...I haven't worked on anything quite this large before.

Sounds like you have a good attitude towards the project, that helps, cause full Neander can be challenging on projects like this. Not sure your experience level, so maybe much of what I write, u already know, if so, hopefully it will help others. The other issue is, you can get both sides of the board FLAT, but not co-planar to each other. That makes for a funky glue up ;) Specially if you want cross boards on the bottom. There is all kinds of tricks to try to keep the board co planar which I am sure you aware of. Using a FLAT work surface is very critical here as well...

It truly is amazing how fast and accurate a powered jointer and thickness planer is. It is one of those tasks after I complete them for longer stock, I sometimes marvel how did ww do this 100+ years ago by hand! All day long, thats all they did. They prob had additional tricks n tips that got lost through time. I am Neander more on smaller projects, where I feel the tools fit the wood size better. A jointer hand plane works great on a 20" long board ;) Although maybe some time in the future, I will challenge myself to see if I can get a rough board your size, flat and co planar.

Yes, the wood will move... not sure how thick the boards are you are starting with...but as you know, as you remove thickness, it moves the most as the outermost areas are removed. So doing the project over many days, paying attention to the movement is advised.

As for movement over time, the cut of wood is critical here. Safest bet, use Rift Sawn for long boards, they are remarkably more stable than quartersawn and surely plain sawn. Of course, a finish that is equally applied to the entire surfaces also can greatly reduce movement. I have walked into a lot of antique stores, and no straight edge was required, excessive movements on some table tops. OTOH, I have seen some 400 yr old pieces done right, and movement was minimal. It really takes a LOT of planning at every step to achieve the end goal in ww. The larger the project, the more obvious movement becomes as errors double with doubling size.

Why doesn't everyone use Rift sawn? 1) not always easy to find, and when u do... 2) in many species, extremely expensive vs. plain sawn, sometimes 3-6x the price per BF, as the waste is so great and labor much higher!

[Tyler Bancroft]

You will likely have better results with a few cauls to hold your boards flush.

If a pinch dog isn't perfectly aligned, it may be the cause of the boards becoming misaligned.

jtk

I was actually considering nailing battens to the very end of the boards to use as cauls - since I will have to trim the last inch or two off anyway to deal with the holes left from the pinch dogs. It seems an inelegant solution, though, and I may well use cauls. Honestly, never having done a glueup of this size, I am tempted to use every solution combined.

[Jim Koepke]

I was actually considering nailing battens to the very end of the boards to use as cauls - since I will have to trim the last inch or two off anyway to deal with the holes left from the pinch dogs. It seems an inelegant solution, though, and I may well use cauls. Honestly, never having done a glueup of this size, I am tempted to use every solution combined.

Place packing tape over the narrow edge of a 2X3s or 2X4s long enough to be clamped across your glue up. Before clamping up the pieces being joined lightly clamp the cauls in two or three place to hold the work flat. Tighten up the clamps across until glue just begins to squeeze out. Tighten the cauls a little more, then across the glue up. It shouldn't be too difficult.

jtk

[Tyler Bancroft]

> Some good open mindedness in this thread!

Why is this always not ALWAYS the case? Forums have such potential, but as seen in a recent post I made on product review of a honing guide, sometimes the comments are so unjust, off topic, offensive, etc. Glad to get back to a normal thread where people helping each other! Thx for the tip Mel on the adjustments...

I find SMC to be one of the most supportive and informative forums I've ever found. Learned a ton here (which reminds me, I'm overdue to renew my contribution).


Sounds like you have a good attitude towards the project, that helps, cause full Neander can be challenging on projects like this. Not sure your experience level, so maybe much of what I write, u already know, if so, hopefully it will help others. The other issue is, you can get both sides of the board FLAT, but not co-planar to each other. That makes for a funky glue up ;) Specially if you want cross boards on the bottom. There is all kinds of tricks to try to keep the board co planar which I am sure you aware of. Using a FLAT work surface is very critical here as well...

It truly is amazing how fast and accurate a powered jointer and thickness planer is. It is one of those tasks after I complete them for longer stock, I sometimes marvel how did ww do this 100+ years ago by hand! All day long, thats all they did. They prob had additional tricks n tips that got lost through time. I am Neander more on smaller projects, where I feel the tools fit the wood size better. A jointer hand plane works great on a 20" long board ;) Although maybe some time in the future, I will challenge myself to see if I can get a rough board your size, flat and co planar.

Yes, the wood will move... not sure how thick the boards are you are starting with...but as you know, as you remove thickness, it moves the most as the outermost areas are removed. So doing the project over many days, paying attention to the movement is advised.

As for movement over time, the cut of wood is critical here. Safest bet, use Rift Sawn for long boards, they are remarkably more stable than quartersawn and surely plain sawn. Of course, a finish that is equally applied to the entire surfaces also can greatly reduce movement. I have walked into a lot of antique stores, and no straight edge was required, excessive movements on some table tops. OTOH, I have seen some 400 yr old pieces done right, and movement was minimal. It really takes a LOT of planning at every step to achieve the end goal in ww. The larger the project, the more obvious movement becomes as errors double with doubling size.

Why doesn't everyone use Rift sawn? 1) not always easy to find, and when u do... 2) in many species, extremely expensive vs. plain sawn, sometimes 3-6x the price per BF, as the waste is so great and labor much higher!

I'd love to have a machine setup that could deal with 6'+, 12" wide hardwood, but I don't have the space or money for that (nor will I in the foreseeable future). And, ultimately, like you said, people throughout most of history have made glorious things from wood using only hand tools, so it's something I enjoy aspiring to (but without much hope, because I don't do it for 60 hours/week like traditional furniture makers used to).

The wood is 4/4 roughsawn, more like 9/8 in spots. I'm expecting a final 3/4, but hoping very hard I can keep an extra 1/16th or so. This tabletop is going on a trestle base, so I'd like the extra rigidity.

I'd love to have somewhere to get 12" riftsawn cherry heartwood. ;) But you work with what you have - and at the end of the day, anything's better than Ikea.

[Tyler Bancroft]

Place packing tape over the narrow edge of a 2X3s or 2X4s long enough to be clamped across your glue up.

Have you seen what a 2x4 costs these days?!

[Will Blick]

OF course, I was not suggesting you find rift sawn cherry...
I was only trying to translate, if you have plain sawn cherry, movement risk is much higher vs. if you are working with Riftsawn, as you asked about movement. What do you have?

If you can get the boards down to 3/4 and flat, depends on how much bow and twist the board has now....
I have power jointed some 6/4 Maple, and could not get to 3/4 as the twist and bow was greater than I thought....of course, if I was hand planing it, I would have measured it all out, marked it up and determined it was not possible...before wearing every muscle out in my body only to find out 6 hrs later ;)
hand tools give you more time to think.
Sometimes when using power tools, I stop thinking, and just do... usually thats when fk ups happen! ;(

[Tyler Bancroft]

It's all flatsawn, but very well-behaved. Very little twist, virtually no bow. I appreciate that you think that my decrepit muscles could do six hours of work...

[Warren Mickley]

In historic times, workers planed an edge flat with no gaps. They used match planing for very thin stuff where it was difficult to balance a plane, but not for thicker stuff.

The spring joint arose around 1880 for machine jointer edges. I don't have enough experience with jointer machines to understand what problem they were trying to solve. The term "sprung joint" is a relatively recent variation. It relies on heavy clamping, which was not really a part of historic repertoire.

[Will Blick]

Well, if its old, and well behaved, that is a good sign!
hey, I didn't know how spry your muscles are ! ;)
Some days I hand plane so much, my entire upper body aches the next day!
I raise the grain with my sweat, saves a step!
I get carried away, like its an iron-man competition!
thats why now, I have reduced Neander work down to smaller projects...

BTW, i find it interesting that so many edges come apart in panel glue ups, hence the spring joint... I never used a spring joint, never had an edge open up. Never seen one either from fellow ww's. Sometimes, I think these issues are older, and just linger... maybe today's glues are soo damn strong this is a non issue today? This assumes you closed the joint during glue up. I marvel how strong glue is today, when I try smashing apart a joint or cut off, etc, never once did the glue line break. But I keep trying! I know modern glues are 3-4k psi strength, my guess is, glues in the 1800's were prob. 1/10th this? Does anyone know? Interest factoid... and would maybe explain a lot of issues ww had then, that get erased today.

I have had entire panels twist on me, but not enough to ruin the top. The reason is, I usually don't wait long enough after jointing / planning to allow for re acclimation. It should be done in stages. Sometimes I feel the boards are stable, and just take my chances if my material removal was minimal... I need to get it done.

[Tyler Bancroft]

Spry has never been applied to me. I mostly have issues with my elbow and shoulder after too much planing, and I expect eventually I'll have to switch to machine prep of rough stock, but for now, you work with what you've got, right? I do plan to build some wooden planes this fall, as I like the lighter weight for some work and it's certainly easier on the joints.

I seem to remember that Popular Woodworking did some glue tests and found that long-grain glueups tended to fail in the wood around the joint, rather than the joint itself. PVA glues are pretty reliable, IMHO. And I know that hide glue is substantially weaker. Interestingly, Chris Schwarz has written about how many examples of older (>100 years older) furniture had joints reinforced by the occasional subtle nail. It makes sense, given that glue joints are likely to weaken with movement over time.

[Christopher Charles]

Hi Tyler,

Fun project. I've done a couple of desktops that were ~60" long full-neander. A couple suggestions:
-Get one face flat on each board (but not necessarily glass smooth-just need a good reference surface for the next step).
-Edge a joint to 90 deg using a square to carefully reference the angle and use a straight-edge to get the length close.
-Repeat with a second board
-Identify gaps by referencing the board off each other. When you get close, you'll experience 'sticktion' when its right and will be able to pivot the boards on the high spots when not. 80" will be a bit of a challenge-may want to practice on shorter boards, but totally doable.
-Repeat for the second joint
-Glue up using cauls to keep the reference faces as flat as possible. I would not trust dogs in this situation.
-Flatten the top and then dress the bottom to final thickness. Note, you'll just need a flat surface for mating to the trestle so may be able to maintain thickness in the middle or taper the sides/edges for aesthetics.

This sequence should keep as much thickness as possible. Will you be using breadboards on the ends?

Best,
Chris
440174

[Will Blick]

Very nice table Chris, impressive all Neander!
I have power jointed so long on bigger projects, I never thought of Chris's excellent suggestion!
just get one side flat, then glue up, then work the bottom for maximizing board thickness...
the bottom does not need to be perfectly flat! Great contribution!

Tyler, yes, we work with what we have, or what we feel like...
sometimes I feel like a Neander, sometimes I don't.
there was times I did not have access to my power tools for a year or two...
when they were in storage during long moves...
and worked 100% Neander only, as that is all the space I had to work in at the time.
I like it all...
A heavy hand planning session is like a weight lifting session!
I loaded my Veritas Jointer plane up with an extra 6lbs of steel weight to give it more inertia...
Great when pushing, hard when picking up a tad on the return strokes!

[Mel Fulks]

Interesting stuff ,Warren. It doesn't always rely on heavy clamping though. Ive been told that bowed instruments had
hollow joints. I used to help a violin maker friend with his plates ,using a plane ,and he asked me to hollow joint. Said he
had seen both old and modern instruments with center joints that had popped open. He never trusted his gluing of plates
even though his violins were "good" and used by some pro musicians.He even mentioned at least 2
makers of at least "good " old instruments being known today as makers whose plates had to be reglued. And
they were not pieces that showed water damage. But I guess most of us have seen some open joints in the paneling of
old museum houses. But I don't blame their methods, I don't really know why there are so many needing regluing.
I do know that in gluing panels for interior or exterior use I have never had a failure. Bad panels had been a big problem for one
place. I told them if they let me do all the facing,planing, jointing for all panels I would give $25 dollars to anyone who
showed me one failure. In 3 and 1/2 years of doing panel work often used for exterior, I never had a claim. The jobs
varied in size but needing 100 panels or more was common.

[Tyler Bancroft]

That jointer's heavy enough without the extra weight! I find a scribble of paraffin wax on the sole makes life a lot easier, though.

I have no compunctions about leaving the underside largely unrefined. As long as I can mate it to the trestles, it's fine by me. I'm past the point in my life where I spend a lot of time laying on the floor under the table anyway...

[Will Blick]

Tyler, I love inertia in a plane. I have a smoother that is 11lbs, as is, not altered, cuts like hot knife through butter, of course, sharp blades still required. But yes, maybe in a few years, my hands and arms will surrender the weight... I cant stop tinkering with things, horrible habit...

Mel..
> In 3 and 1/2 years of doing panel work often used for exterior, I never had a claim. The jobs
varied in size but needing 100 panels or more was common.

What type of exterior panels are these? Siding? how are they joined? What type of glue, TB3? What type of weather exposure? Pix?
Very interesting... exterior is the ultimate test for wood (and finish), specially when sun hits part of the panel, but not another part, so now you have varying expansion and contraction.
not trying to hijack Tylers thread, hopefully relevant enough...

[Tyler Bancroft]

I didn't realize they made planes out of platinum...

(And I'm curious, so hijack away.)

[Tyler Bancroft]

Hi Tyler,

Fun project. I've done a couple of desktops that were ~60" long full-neander. A couple suggestions:
-Get one face flat on each board (but not necessarily glass smooth-just need a good reference surface for the next step).
-Edge a joint to 90 deg using a square to carefully reference the angle and use a straight-edge to get the length close.
-Repeat with a second board
-Identify gaps by referencing the board off each other. When you get close, you'll experience 'sticktion' when its right and will be able to pivot the boards on the high spots when not. 80" will be a bit of a challenge-may want to practice on shorter boards, but totally doable.
-Repeat for the second joint
-Glue up using cauls to keep the reference faces as flat as possible. I would not trust dogs in this situation.
-Flatten the top and then dress the bottom to final thickness. Note, you'll just need a flat surface for mating to the trestle so may be able to maintain thickness in the middle or taper the sides/edges for aesthetics.

This sequence should keep as much thickness as possible. Will you be using breadboards on the ends?

Best,
Chris
440174

That's a nice desk. The grain on these boards is quite beautiful, and I feel like breadboards on the end may detract from the appearance. That being said, given the width of the tabletop, I expect I'll need the breadboards for stability. I want to finish cleaning up the (very) rough-cut finish before I make any final decisions. Your strategy is roughly what I was thinking. I'm not too concerned with the appearance of the underside, as long as it's flat enough for a good fit with the trestles. As well, I'm hoping the little bit of extra thickness I'd save from not getting the underside perfectly flat will help with stability and rigidity. Given the structure of a trestle table, I'll take all the rigidity I can get.

[Will Blick]

Not platinum! (did I write that by accident?)
Brass and steel...
Correction, the smoother is 9lbs... my bad...

[Will Blick]

Chris, what finish on the table?
Is that poly ? nice sheen...

[Alan Schwabacher]

The spring joint arose around 1880 for machine jointer edges. I don't have enough experience with jointer machines to understand what problem they were trying to solve.

Could it have been use of incompletely dried stock that would subsequently dry faster from the ends?

[Tyler Bancroft]

Could it have been use of incompletely dried stock that would subsequently dry faster from the ends?

I thought it was to reduce the tendency of glueups to separate from the ends due to greater seasonal movement near endgrain than in the middle of boards.

[Mel Fulks]

I thought it was to reduce the tendency of glueups to separate from the ends due to greater seasonal movement near endgrain than in the middle of boards.

Agree with this and Alan . The ends do dry out faster ,since they exposed to air. And most agree that air dried wood
will move more than kiln dried in the same room. Some find kiln dried wood harder to plane. Kiln drying is baking. And
some prefer the unbaked dough.

[Will Blick]

Interesting...
So Mel, do you spring now because you always have... i.e. habit / style..
or do you feel if you joint straight, you will have problems?

[Mel Fulks]

Will, I'm retired now and don't own or need a jointer for my constant work on house stuff. But if someone asked me to
work in their shop for a few days I would work same methods. And if asked to deviate from my habits ,I would just go
home.

[Tyler Bancroft]

Not platinum! (did I write that by accident?)

Nah, just trying to figure out how to make a smoother weigh 11 lbs...I think my Veritas #4 weighs about 4.5.

[Will Blick]

I just sold this one... it weighs 9.5 lbs
it is a miter, or move the knob and its a smoother

http://www.marcouplanes.com/Marcou_Planes_21_Handplanes.php

[Will Blick]

my smoother now, actually 8.5lbs (I had corrected it above)

http://www.marcouplanes.com/Marcou_Planes_25_Handplanes.php

[Jim Koepke]

Have you seen what a 2x4 costs these days?!

My travels have been limited of late. Looking online it looks like they have jumped quite a bit in price. Not sure if it is due to less milling of lumber, fires or storms.

440189

2X3 lumber will work and a bit less expensive.

jtk

[Tyler Bancroft]

Will, those are gorgeous. When I win the lottery, I'm buying one of each.

[Tyler Bancroft]

My travels have been limited of late. Looking online it looks like they have jumped quite a bit in price. Not sure if it is due to less milling of lumber, fires or storms.

440189

2X3 lumber will work and a bit less expensive.

jtk

I was mostly joking, but it is getting silly - around here, they've gone from <$3 to >$6 CAD. And I can drive ten minutes and be at a softwood mill...

I'm not sure where all the supply is going, with COVID. Is everyone building triple-decker decks or something?

[Will Blick]

Oh, and as per a previous post...
I too wax my soles, like every 10 strokes ;)
fully agreed, what a difference it makes...
greatly reduces friction.
If u never tried, rub some hard bees wax on, or even parafin...

[Tyler Bancroft]

Oh, and as per a previous post...
I too wax my soles, like every 10 strokes ;)
fully agreed, what a difference it makes...
greatly reduces friction.
If u never tried, rub some hard bees wax on, or even parafin...

I've never tried beeswax. I'd think it'd be a little too sticky. I bought a $10 box of canning paraffin wax a couple of years ago that should last me to retirement. It's handy on saw plates, too.

[Will Blick]

In warmer weather, the parafin is best for sure. Yes, one block will last your lifetime... hee hee... talk about amazing value!
In cool weather a few bees waxs I found, works great too, but its costly and you go through more... tried to find the link, but they must be out, or dont make it anymore...

I had a thought about flattening the boards, something I imagined once, but never tried.
If you have a long flat work surface...
put fine sandpaper down long enough to cover board... full length plus and extra sheet or two...tape it down..
put top of board face down....rub board up and back a few times... flip over...
the sand paper should identify the high spots, plane em down, rinse and repeat...
Of course, this assumes the board is reasonable shape to start with, it wont work with heavily twisted boards...

[Dennis Droege]

For what it's worth: I have, over time, gotten to a point where preparation time trumps awshit time, and if I approach a jointing job when I'm right to do it, I don't get much gap. And I don't like spring joints (my opinion only). I like two pieces of lumber that, regardless of length, make a suitable appearance when joined by hand pressure in a dry rehearsal. And yeah, do the glue as soon after the last plane stroke as I can; most wood will move, and that's what I love about it.

[Daniel Culotta]

I read an article recently that said tons of mills shut down at the beginning of COVID because everyone thought the housing market was going to implode. Now it’s humming along, but the lumber supply is way short. Something like $14k on average added to home prices due to increased lumber costs, and they expect supply to catch back up by the end of the year.

[Warren Mickley]

Wood splits most easily along the radial surface. For a plain sawn board that means the most vulnerable place on end grain is right in the middle of the board where the rings are flat and the radial surface is perpendicular to the board. Not so much near the joints. There is not a problem with joints that are well mated and not spring joints. If the worker cannot make a flat joint, however, a hollow joint is probably preferable to a convex joint.

Antique furniture was made with hide glue. Hide glue becomes brittle with age and can shatter with a sharp blow. That is a very good thing if you are trying to get a joint apart for repair work. An edge joint can shatter and have to be reglued.

[Christopher Charles]

Hi Will and Tyler,

Thanks for the kind words, I was pleased with the outcome.

Tyler, I'd definitely consider breadboards since you won't have aprons to hold the top flat.

Will, the finish was oil, shellac and then wax. Probably should have put a coat of poly on top as it was for my son....

Best,
Chris

[Mel Fulks]

My take on how the spring joint works : by slightly compressing a little wood there is "extra" wood at joint board ends. When end
grain gets wet it expands making compression. That makes the wood narrower as it drys. When wet again it can not
fully recover former width. Wood scientists call that "compression ring set". This explanation is my understanding from
a scientific piece read years ago. I'm sure it can be found on line.
I failed to answer a question last night about what kind of exterior panels I had mentioned. They were a bad
idea of a band of wood paneling going all the way around house ,just above foundation. Had I been the company
salesman I would have refused to take the job. I'm sure none are still around ,except the ones on front porches.

[Will Blick]

Interesting finish, never tried that.
Do u always oil before shellac? If so, why?

[Christopher Charles]

Usually I do a coat of oil before the shellac because it helps pop the grain. And I think nothing beats shellac for a finish that gives depth without looking and feeling like plastic.