JoshuaCarlsen

Joining 45 degree miter cuts

Recommended Posts

I thought I had a jig for doweling a 45 degree joint. I don't. Now I need to finish my tool box and can't join the edges. I was looking to start my festool system but I don't want to spend $900 bucks for the domino. I was thinking about buying a biscuit joiner. Does anyone have an idea on a decent one to buy?

Share this post


Link to post
Share on other sites

This is an alternative but, if I only had one project for it I would shop-make one.  Do you have a drill press? Splines that show can be done with a handsaw.  What is the material of the carcass?

 

Share this post


Link to post
Share on other sites

Here's and option:  Gl;ue the box together by applying glue to both surfaces of each piece. Let it dry for about 30 minutes and then apply glue a usual and glue it together.  Blue several pices of blue tape can be used to hold the corners together.  Then drill holes into each corner from each side (any pattern you want just make sure they are staggered) and insert glue and dowels cut from longer dowel stock.  If your sides are 3/4" thick, I would drill 1 1/2" deep.  The dowels will be exposed in the finished piece.  Gives a nice look.

Share this post


Link to post
Share on other sites
52 minutes ago, JoshuaCarlsen said:

I was looking at this exact product but I don't see how it works for a 45 degree joint.

Find your center point along the length of your miter. Using a square against the 45* edge, mark a line Down the board at your center point. Depending on the width of your board and the length of your dowel, you may have to adjust you line to accommodate the length of the dowel or shorten the dowel. The jig has a line marked down the length of the plastic clamp plate. Align both lines and clamp the jig to the board and drill away. 

Share this post


Link to post
Share on other sites
48 minutes ago, JoshuaCarlsen said:

I have never done splines. I have only scene it done in videos. Also I don't have a table saw. 

Splines are pretty easy and can be done with hand tools. Just takes some careful marking and sawing with a handsaw. Easier with a table saw or router table,  it it can be done and they’re pretty darned strong :) 

Share this post


Link to post
Share on other sites

Here ya go. I offset the lines to make them more visible.

613847CB-3BBD-4167-8044-BCEC6150E713.thumb.jpeg.196c901ad3ae099e7caefa6f0f8f2bfa.jpeg

  • Like 1

Share this post


Link to post
Share on other sites

Coop, did you have to tweak that jig to make it square? I received one last Christmas, and the marks are a hair off center of the holes, so nothing lines up.

Share this post


Link to post
Share on other sites

I only used it a couple of times prior to buying the Domino but don’t recall any problems. I do see that is is some slop or room for adjustment that can be made with a good square. 

  • Like 2

Share this post


Link to post
Share on other sites

There are a few ways to attach butted mitred corners. 

1. Glue with “sizing”. End grain is a bunch of straws, and this tends to suck up glue, with the result that the joint become glue-starved. Glue can hold a butt joint very well. - see how well panels last with just glue - however there must be glue to do so. 

Sizing is using glue to seal the straws before glueing. Water down some of the glue you plan to use, and wipe it into the glue area. Let it get 90% dry. - a touch tacky - and then add the regular glue, and join the pieces together.

2. Reinforce the mitre. Create a spline using a table saw or router table. Generally, 3mm (1/8”) thick will be fine. My saw blades are 3.2mm wide. The orientation of the grain for the spline is important. You want end grain facing out. 

3. Use biscuits, dominos or dowels. A spline is the strongest method because it can run the full length of the joint (or near-full length if the mortice is stopped). This is where biscuits can score over dominos - the biscuit is shallow but long, while a domino (and way back in third place, the dowel) is deep but narrow. This limits where you can position a domino or dowel. 

4. Dovetail splines at the top and the bottom of the mitre. Chisel these out.

5. Splines through the outer corner edges of the joint. May be done using a sled on a table saw or router table. Or use a biscuit machine. If you like the look, of course.

Regards from Perth

Derek

  • Like 2

Share this post


Link to post
Share on other sites

This is the perfect application for domino or dowel. A dowel jig can  easily be shop made from scrap in 5 mins. Just do a quick google search for it.

If the underside is not visible, you could also add a gusset pretty easily.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.