Lap joint size - Router Forums
  • 1 Post By ranman
  • 1 Post By Cherryville Chuck
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 09-04-2018, 11:10 AM Thread Starter
Registered User
Join Date: Oct 2017
Country: United States
First Name: Randy
Posts: 310
Default Lap joint size

Are there some sort of standard dimensions for lap joints based on material thickness?.......... such as 1/2 the thickness?
sreilly likes this.
ranman is offline  
Sponsored Links
post #2 of 4 (permalink) Old 09-04-2018, 11:47 AM
Registered User
DaninVan's Avatar
Join Date: Dec 2011
Country: Canada
First Name: Dan
Posts: 15,080

Half the thickness makes a lot of sense for the simplest reason that it means the machine setup is the same for all pieces. The 'KISS' principle in all its glory!
If you want to complicate your life you could go with this...
Woodwork - Bridle Joint information and Pictures
DaninVan is offline  
post #3 of 4 (permalink) Old 09-04-2018, 02:32 PM
Forum Contributor
DesertRatTom's Avatar
Join Date: Jul 2012
Country: United States
First Name: Tom
Posts: 18,427

That's the secret. The closer you get to the middle, the better the joint will look, otherwise you'll have to sand, sand, sand, sand, sand to even it up. Get Terrie Noll's "Joint Book" for the last word on all kinds of joints. I'll be using lap joints to make stage scenery flats, and hitting the half way point precisely is important when you have from 6 to 8 joints per flat. You don't want to do much hand work. Glue on a lap joint will make it almost impossible to break.

A video I saw a couple of years ago had the builder cutting to the half way mark with a Japanese pull saw, and using that line to guide the router. Flats are made of soft pine so he just plows through, but with hard woods, you'd want to take off layers.

I saw a recent post that showed a very large mortising bit that was just for this kind of flattening, but I can't find it just now.

The more I do, the less I accomplish.
DesertRatTom is offline  
Sponsored Links
post #4 of 4 (permalink) Old 09-05-2018, 01:05 AM
Moderation Team
Cherryville Chuck's Avatar
Join Date: Sep 2010
Country: Canada
First Name: Charles
Posts: 16,063

Like Dan said, once you fine tune your setup to take off half the thickness you can make good time and you also don't have to worry about matching A to B. All pieces are the same.
Herb Stoops likes this.

Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.
Cherryville Chuck is online now  

Quick Reply

Register Now

In order to be able to post messages on the Router Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Thread Thread Starter Forum Replies Last Post
The difference between a box joint and a finger joint bit Mike Router Bits - Types and Usage 6 09-08-2014 01:21 PM
Groove and Tennon Joint Construction neville9999 General Routing 3 11-19-2013 10:15 AM
Router bits for a rule joint davidaoh35 New Member Introductions 2 10-05-2013 05:04 AM
Lap Joint Jig Technogramps New Member Introductions 5 07-16-2012 02:47 AM
need half lap joint jig DJeansonne Jigs and Fixtures 11 08-17-2009 09:27 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome