Episode #14: Porringer Tea Table – Part 3

Note: All of my old podcast videos have been moved to my YouTube channel.  You can now watch this video here:

https://www.youtube.com/watch?v=9PdwJTW8XdE&t=25s

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15 thoughts on “Episode #14: Porringer Tea Table – Part 3

  1. Wow, just when you think you’ve seen every way possible to do layout and cut a mortise you come along and make it easier and more logical. I knew to do layout off of reference faces but for some reason it never occurred to me that these should be the joinery faces as well. Also, when chopping mortises I’ve been starting at one end and working my way to the other in a layer by layer fashion. I like your way of starting in the middle and making a Vee and orinting the body to ensure plumb joinery. No wonder I was having problems with my aprons being twisted! Thanks Bob. Very helpful!

    • Thanks Jason! Glad you found it useful. I was going to discuss a little more why I typically use the joinery faces as my reference faces, but the video was already getting long, and when I get talking…..I decided instead to make it a separate topic for a Quick Tip video. There is a good reason that I use the joinery faces as the reference faces (when I can). It’s not just an arbitrary choice.

  2. Thanks for the great video Bob! As Jason said, thanks for taking your time and filling the video with great tips for every step.

    It wasn’t clear how the haunch is going to help with the apron twist? Are we going to cut the tenon a little tall, and use the haunch to squeeze it in? I could see how this could help strengthen the joint, but I don’t understand how it will help with the twist.

    • James, thanks for the feedback! The haunch allows the tenon to be wider, albeit more like a stub tenon at the haunch. The THEORY of the haunch is that by containing as much of the apron’s width within the mortise, the mortise acts to prevent the apron stock from cupping or twisting during seasonal changes. If the tenon were narrower, the top of the apron (above the top of the tenon) would be unrestricted and free to cup or twist. We see this most obviously in a breadboard end where there is a square haunch on each end of the tenon (as opposed to the angled one here. In reality, I think it’s unlikely that it makes any difference for relatively narrow aprons like these. But I figured it was another teaching/learning point for folks who haven’t done M&T before. It is useful for wide aprons like those of dressing tables and highboys.

  3. I just found your site. It is very informative and well done.

    In reference to the depth of mortise and having a barefaced tenon or tenon with only three shoulders. Most often the corners of tables and chairs fail at the corner where two tenons meet in the mortise as there is no wood left to strengthen the leg itself. If you push the tenon toward the outside face, therefore leaving a shoulder on the inside face you will gain two things.

    First you will be able to leave some material in the leg joint instead of removing all of it and replacing with an endgrain joint. Also you can add length to the tenon if necessary to gain glue surface and strength.

    The resulting inside shoulder need not be perfect so it really does not hamper the fitting or appearance of the overall joint, unless you flip the table or chair over.

    It has been my experience both from building and repairing period pieces that the ability to have separate mortises without an intersecting tenon, will increase the longevity and success of the joint.

    Of course you will need to take into account the amount of material between the outside face of the tenon and the outside face of the leg to make sure there is plenty of material to support the joint. However I would rather shorten the tenons slightly or push the tenon outward in order to make a stronger joint.

    • Floss,
      Thanks for the feedback and the suggestion. They are all valid points. These aprons are pushed about as far toward the front of the leg as they can get. The fronts of the aprons will end up flush with the fronts of the legs. For this reason, I decided on the three shouldered tenon to provide a thicker front mortise wall, which in my mind would be stronger, and to simplify construction & fitting. Of course this creates the void inside the leg which you speak of due to having the two mortises intersect. Moving the mortise closer to the front of the leg is certainly an option, and in combination with shortening the tenon, would certainly make for a stronger leg as you suggest. However, this would also make the front mortise wall thinner. This wouldn’t be a problem as there is plenty of thickness there, except that I’m going to be drawboring the joint. So if I make the front of the mortise wall too thin, I risk splitting the mortise side. Pushing the mortsie back slightly and only using a three shouldered tenon allows me to leave maximum mortise wall thickness for draw boring the joint. Of course, I could have just shortened the tenons by 1/2″ to make sure the mortises did not intersect, but this would have left me with tenons only 3/4″ long, which I didn’t think was enough for a table like this, especially one that would be draw bored. In the end, you are 100% correct that I most definitely made the leg weaker by using intersecting mortises vs. two completely separate mortises, however, I don’t expect that this table will see enough abuse in my house to test the strength of the joint. It may well be something that others building the table may want to consider though if they expect theirs to see more [ab]use. Thanks for the very informative post!

  4. Hi Bob, just watched the latest episode and have to say that I really like your method of chopping mortises. Most of the methods I have seen are similar to what Jason has described in his comments above. Your podcasts are immensely informative-keep up the great work!!

    • Steve, Thanks for the feedback! I’ve tried several different methods of mortising and this one was the easiest and fastest for me to use so I stuck with it.

  5. Bob, have you considered getting in touch with publishers to make videos/DVDs? These videos are extremely informative, and I think by the time you are finished with this series, you could even cut your podcasts into a few DVDs with the footage that you have already shot! Thanks so much for putting the time into these.

    • Kenneth,
      Thanks for the suggestion! I’m not sure the video I’ve shot and produced to date is DVD quality. I’ve gotten a similar question/request a few times and I am extremely flattered and honored that folks think the material in my podcast is worthy of sale.

      However, I’m really not in this to make money. I started the podcast because there was nothing else like it out there at the time and I really wanted to just share what little I have learned and my experiences as I learned new stuff. Most of what I write and demonstrate isn’t new information (much of it is from 17th, 18th and 19th century texts) and a lot is stuff I’ve learned from other folks a lot more knowledgable about this than me (Adam Cherubini, Mike Dunbar and Don McConnell just to name a few). I’m no where near the caliber of craftsman that these guys are. They’ve done most of the work, I’m just presenting the information in a form that didn’t previously exist and trying to put it to work on real life projects. I’m just happy and honored that there are folks out there that are interested in watching it.

      • Bob, I understand and very much respect that. 🙂

        I do video work (among other things) and you’d be surprised at the quality of the source that I get sometimes. With some editing and some flair here and there you can really make something sing.

        It’s just a thought, but you could even pull a Schwarz and donate profits to a charity. I just think that you’re offering something very practical and interesting.

        I’ll just do my part and spread the news! Thanks again for all your work.

  6. Hey Bob, great video series, and I think I will try your method of chopping mortises. I generally use a different method, where I chop about 1/4″ from the far end mark straight down, then chop a series of cuts all the way down the mortise, using the bevel of the chisel to ‘ramp’ away the material, till about 1/4″. Then flip the chisel and do another square cut on the near end. Repeat to depth. But your method makes the depth apparent immediately, and this ramping cut can still be used. I often get a little hump right in the middle of the mortise using my normal method. Personally, I’d skip the haunch if I was following along (too many other projects right now, but maybe over the summer), but thanks for including it for teaching reasons. There are other times where the haunch is needed and it is nice to see how you pare it out.

    • Joe,
      Thanks for the comment! I agree, the haunch isn’t really adding much here in terms of strength and therefore could be omitted. It is much more important in pieces with wide tenons, like a dressing table, or a breadboard end. Regarding the mortising method, I’m not really sure where I picked it up (probably just through experimenting) but it works really well for me so I stick with it. It allows me to chop mortises really fast, and I like that.

  7. Hi Bob,

    As I’ve mentioned in the previous podcasts – THANKS. I marked out my mortises and chopped out the first leg using my Lee Valley bench chisels. Then I did what I have wanted to do for quite some time and went ahead and ordered myself a Ray Iles mortising chisel. Wow! does that thing have some heft to it.

    Although the instructions say you should be able to use it as is I did touch it up a bit on my stones. Still could use a bit more, but I have my mortises done and am ready to move onto the next video.

    Very fun project!

    • Jeff,
      Good to hear you are making good progress! Congratulations! As you have found, using a bench chisel really isn’t appropriate for chopping mortises. In fact, it’s a good way to snap the chisel in half. They just aren’t meant to withstand the forces of mortising. If you need to chop a mortise and only have a bench chisel, the safest way is to bore out the majority of the waste with a brace and bit and clean up the joint with the bench chisel. However, as you have found out, a proper mortise chisel makes a world of difference and really is a must have tool for anyone wanting to make this joint by hand more than once. Keep up the good work and be sure to send me some pictures of your table when you’re done.

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