Friday, October 28, 2011

How I Wood Do It "The 1/2 Lap Joint"

This is the first of a monthly feature we are calling "How I Wood Do It" each month a few of us bloggers will be posting how we would do a different technique in our shops. Hopefully this will give you, our readers a different point of reference on a simple techniques. Well lets get to it shall we. 


The Half Lap Joint



The half lap? Really how often is the wood joint really used in every day woodworking?  It is a strong basic joint, that is fairly fast and easy to make, and is one of the first most people learn in classes.

It is used in everyday woodworking! Well, I worked in a shop in the 80s that build pine face framed cabinet and the owner swore by half lap joint to assemble the face frames, so I learn to cut them quickly and accurate, we had many heated debates in the shop over this joint compared to using the mortise and tenon as well as some other joints for the same application. We really wasn't set up to to cut mortises in the shop and didn't want to invest in any more tooling and we could do the half lap quickly with the tools we had. Since then I have used this Half Lap Joint for a lot of projects since it is a strong easy joint.

This is how I cut the Half Lap Joint.

If I have to cut a lot half laps, I like to do it on a table saw either using a single, or a dado blade. I like the table saw better, because if you screw up and the wood happens to lift up off the table top the blade cuts into the waste material and can't cut into the material that is the joint and you won't ruin the cut by cutting into it. If you did this on a sliding miter saw or radial arm saw and the wood lifted up it would cut though the waste and into the joint itself. 

If I just have a single joint or two to cut, I use a making gauge and a hand saw to cut out the waste and clean and fit the joint with a shoulder plane. Some times if I have more than a couple or if I am in a hurry I will use my band saw to replace the hand saw part of the operation, but the rest is the same.
  • I first make sure the sides and face are planed flat and square and put a X on my reference face and edge.
  • Then I  find center with my marking gauge.
Setting the marking gage for center
  •  I do this by marking a dot from each side then by trusting my eye to judge center I readjusting my gauge to the center then checking it from each side again and repeating again if needed, the more you practice this the better you will get at doing it in just a couple of try's. 
Checking the right side


Checking from the left side
  • I then mark three lines on both boards, one on each side and the end the board, and then square a line the width of my boards from the end. marking from my references face which I always layout from I also mark the waste on my reference side.
The waste marked with an X

Both sides laid out
  • I saw down the waste side of the line, and then crosscut across following my squared lines until the piece falls out
Starting the rip


Following the line down to the crosscut

Following the line

Defining the line

Finishing the cut
  • I then use a shoulder plane to clean up and adjust the lap joint till it fits.
Adjusting with a plane

Easier to plane when they are clamped side by side
  • My power tools solution since is to use my band saw. again I make sure the sides are planed straight and all the layout is the same as using a handsaw
Crosscutting on the bandsaw

Ripping on the bandsaw

Ripping the the 2nd lap on the bandsaw
  •  I carefully cut the crosscut till I get down to my layout line then I rip it on the waste side till the scrape falls out then I clean and fit it with a shoulder plane. if I had more than a few to do I would set up a fence for this part with the waste side toward the fence.
Checking the fit

Clamped together @ 90 degrees


Another view
Next Month we will be doing "Mortises

Below are some of the other Blogger and Podcaster that will be joining in this monthly feature next month will be the official start and not ever person on this list will be able to participate each month, but hopefully enough will that we will get a wide variety of experience and insights that we will all learn something. As other bloggers join in I will add links to their sites so you can just post though to them right and each bloggers will do the same making it easy to find all the postings. If you are a blogger or a podcaster and you would like to participate let me and I will give you the details.




Oldwolf Workshop Studio
Sandal-woodsblog
Tomsworkbench
Sawdustislife
Thewoodninja
Penultimatewoodshop
Scottmorton
Flairwoodworks
Ravinheart
Americancraftsmanworkshop

2 comments:

Timberwerks Studio - Dale J. Osowski - Furniture Maker said...

I'm interested in being part of Hoe I do it Friday. I can only offer photos though, no video. It would be via my http://djofurnituremaker.wordpress.com/ blog but a link will be provided via http://timberwerksstudio.blogspot.com/ as well

Trevor Walsh said...

I'd like to opt-in as well. How do I do that? My blog is www.twdesignshop.blogspot.com