Tuesday, January 1, 2019

American Trestle Table - Part IV - Notes for the Pause

I was able to get a surprising amount of shop time in over the holiday. Sadly it wasn't enough to finish this table before I go back to Spain. I'll have to finish it up next time I'm here - probably this spring.

Lucky thing my client won't need the table until at least after September. Maybe later.

I did some real thinking about what to do since I made mortises in the upper supports rather than cut joinery for bridle joints. I decided to go with what I have. The tenons will be plenty strong (probably stronger than bridle joints), but to make them look less weird, I sawed about 1/2" of depth from each of the supports. This will give a little bit of  distance between the top of the trestle's mortise and the horizontal edge of the support.

I think if I hadn't done that, the bottom of the support would touch the top of the trestle's mortise and look weird.

Let's get to it:
Layout lines for the lower tenon on the leg
Layout is critical for this. I'm not used to committing like this. Whatever I mark now is the final height of the table, period. I decided to make the table a standard 30" height. To get that, the end of the bottom tenon must be 30" from the end of the upper tenon - less the 40mm thickness of my table top.

Considering that I already had a mortise in this beam, The end of the upper tenon had to be exactly six inches above the bottom of the trestle's mortise. This is because the trestle is six inches thick, and the bottom of the trestle rests on the bottom of the mortise.
Exactly six inches above the bottom of the mortise.
So the pictures are in the wrong order. I marked the end of the upper tenon, then marked the length of the entire leg (the end of the lower tenon). After that, I marked the shoulder line for the lower tenon and cut the tenon.
I missed my honking BadAxe tenon saw. It's perfect for this kind of joinery.
After some tuning of the tenon with my router plane, the tenon fit perfectly.
Three more to go.
While doing all this, I had been suffering with an Ohio O7 jointer plane that wasn't quite working right. I never had the time to rehab it, so I was just using it with a Hock replacement blade.

The problem was I was getting some chatter. But not chatter like I had ever seen before. The wave of this chatter was really slow. You couldn't really see the bumps, but you could sure feel them.

It turns out there was a nasty hump on the face of the frog. Likely this plane never worked well for anyone, even when it was brand new.
A few swipes on my stone shows a nasty hump.
I got the frog 90% sorted, and it made a world of difference with the jointer. It's still not perfect, but it got me through sizing the beams.

Next I sawed the upper braces so they were a bit thinner, as I described above.
A well tuned ripsaw is a wonder.
After this workout, I did it again on the second one.
Two of these rips is a lot like work.
After cleaning the rough surfaces and planing to exact thickness, I cut tenons on the uppers the same as I did on the lowers.
Look! Some sticks!

Now that all of the mortise and tenons are cut, it's time to fettle them. It's been a long time since I used a shoulder plane for this job. I learned how to do it with a chisel for the sake of having that skill. It's a great skill to have, but I decided to pull this shoulder plane out one last time before I sold it.

Holy Moly! I forgot how easy this made tuning tenon shoulders. I was done with four perfectly tuned tenons in about twenty minutes. I'm sure I could have done it with a chisel, but it would have taken hours to get them to the level of perfection they are at with this tool.
I suppose my LN large shoulder plane has earned it's place back in my tool chest.
After that's all ready, I marked out the taper of one of the upper supports. First I marked the centerline on the middle of the the mortise, then I was able to mark out an equal length to each side from there. The end of these braces will only be one inch thick, so I am now able to mark the taper to give an even taper all the way to the leg beam. It's just a matter of cutting it out.
Another job for the rip saw.
I was only able to get the one support roughed out before my shop time ended.
When I get back to this project in a couple months, I'm sure I'll forget what I was doing, so this post is mostly a reminder for my future self.

Future self: the next thing that needs to be done is to plane the taper on this brace down to the line and smooth it out and cut the ends to length at the angle I marked. Then once the other is done, the taper on the feet can be done. But not so aggressive of a taper!

Once everything is shaped and smoothed, the beams can be planed to thickness so the surfaces all meet. Next is a chamfer.

I suggest to my future self to make the trestle and fit it before drawboring and wedging everything. You know how you are!

As far as the slab top goes, it needs just a little bit of work: a big chamfer on the underside to thin out the look of it, and some epoxy for the little cracks in the center.

Hopefully I won't forget I wrote this here until after I've done something irreversible.

6 comments:

  1. I've done trestle legs a few time and because a) they've been drawbored and/or wedged in softwood b) never really as accurate as I thought they were, ... the final legs have never come out to be perfectly aligned with each other. Now I save my final shaping until after they've had a chance to rest.

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    1. Hey Paul, thanks for the comment. These two are surprisingly square to each other so far. But you have a good point. I'll take a close look and make final adjustments just as you say.

      Cheers!

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    2. You have made an incredible progress in this build.
      You can't have spent much time procrastinating in this build :-)

      Brgds
      Jonas

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    3. Thanks, Jonas!

      I felt like I was really in the groove. Hopefully I'll get the momentum going again when next I'm in Munich.

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  2. Looking good Brian! Its a pleasure reading along as your project progress

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    1. Thanks, Ty!, It's too bad you'll have to wait so long before I get back around to it.

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