jack miter progress

[Gary Katz]

Moments in our life are marked by sense imagery--the things we've seen, smelled, touched, heard or tasted, stored on in cells. That was a good one of picking up your check.

I've visited Jeff's old thread, and woodweb and think the router--as usual--is definitely the way to go. I'll make a jig. I don't have time this week, but I think it will be just like a flush bolt jig, almost exactly, and using a template guide bushing with a 45 degree chamfer bit, with a bearing and ground so it cuts a flat bottom, just like the fellow on Woodweb suggested.

The template will start with two piece of 1x3 vertical, spaced apart the thickness of the casing (3/4 in.), though there can be plenty of slop. The top of the template will look just like a hardware or hinge template: two long runners, two shorter spacers ripped the size of the chamfer bit plus the distance to the template guide--plus some more because that dimension doesn't matter and ripping them wider will allow you to work on thicker stock, too.
The space between the spacers can be wide, too. An adjustable stop can be installed on the bottom of the template, positioning a stick of casing perfectly for the jackmiter, and that way the ends of the heads can be cut to exact size. For mull casings, remove the stop and position the jig twice.

I drew a rough sketch. I'll work on it later this week.
http://www.garymkatz.com/trimtechniq...k-miterjig.htm

Gary

[HenryP]

Gary:
As usual, great use of SketchUp.
Looking forward to reading more in the future.
Henry

[jim@miterclamp.com]

Gary,

Justin's post got me to thinking too. Be sure to keep us informed - especially if you get any fuzz up or tear out in the groove or bead on the left side of a head the mull fits into.

regards,

jim

[Al (Ca.)]

Gentlemen,
Excuse my ignorance, but I wonder if there is a more educated term to describe the type of miter you guys are talking about.
I want to understand your exchange and I feel helpless.
I run a search for “jack miters” and got nothing.
I have a beautiful book titled “The complete Illustrated guide to Joinery”, by Gary Rogowski, loaded with beautiful pictures and describing what I think is every imaginable joint possible and still nothing it is said about “jack miters”.
This thread sounds like rocket science to me.
Thanks to anyone willing to take the time to enlighten me.
A picture or drawing will greatly help.
Al

[HenryP]

Al:

Picture a stair tread and separate return nosing.
With casing, the legs are cut to meet the leading edge of the flat at the head and the head casing runs past on the left and right (but cut flush with the outside edge of the leg casing).

The most common casing will be a 2 piece...flat stock with a bead on one edge and a back band at the perimeter.

If there is a bead on the interior of the casing, the head and leg need to meet properly with a miter (or cope).

Typically the bead is removed from the head casing and the joint is a miter at the bead and a 90 degree "butt" at the flat portion.

The legs are cut at 90 (with a back cut) and then the bead is cut off at 45 (just the bead). Legs are easy.

The heads are the tricky part...the bead portion that will butt the top of the leg casing needs to be dressed off and a miter put on the end of the bead run which will join the bead miter at each leg.

Its the mulls and the head cuts for mulls that make this fun (especially with stain grade). And even more fun with arch heads. This discussion is primarily how to prepare the head casings and the best way to remove the section of bead that would be in the way of meeting the top of the leg casing.

Henry

[jim@miterclamp.com]

Al,

The bottom picture on this page is a cabinet rail jack mitered into a cabinet stile on a face frame. Looks like an applied bead to a butted casing, but is actually much faster and better this way. On cabs, intermediate stiles are solidly backed by the bottom shelf and are thus much stronger and cannot be kicked out except by people who are inside the cabinet.

My scanner don't work, and I probably couldnt find any other pics anyway.

But this should be clear enough taken with Henry's description.

http://www.miterclamp.com/radius/pages/Crown.htm

jim

[jim@miterclamp.com]

http://forums.jlconline.com/photos/t...s.php?album=15

Some more with one piece casing that Jeff B posted a while ago.

http://forums.jlconline.com/photos/t...s.php?album=15

[Al (Ca.)]

Jim & Henry,
Thanks for the explanation.
Now I understand what you guys are talking about.
Here is a site that shows something about the making of jack miters.
The final product can be seen at the bottom of the page.
It takes about a minute to download.
http://www.infinitytools.com/PDF/RailandStile.pdf

[Msloggatt]

Al -
That Photo is a style & rail - Not quite a 'jack' mitre -

I've pulled apart tons of 'jack' mitres in old remodels from the arly 1900's all were done by hand, So I never thought about doing them any other way....... Duh..... I run the straight on a table saw & cut the mitre by hand with a japanese pull saw.. Sometimes istart the 45 with a Lion Mitre trimmer & finish off with a chisel

Mike

[cratylus]

I've seen a local shop fit jack miters by milling up a separate bead for the head casing... then just trim to length with miters on both ends and slide it in... a little glue and a few brads and you'd never know.

Seems pretty quick to me.

Joel

[HenryP]

Joel:
This is done with face frames.

With casings, often the fastener has to travel through the bead into the jamb. I guess with very heavy (thick) jamb stock, it is possible to tack the bead on later but this would also make it more difficult to control the margins or reveal at the casing and jamb. It's best to have a single piece of casing stock span the jamb and frame. Best also to hand nail (oh oh) the bead as you have better control over nail placement.
Henry

[phillip]

Originally Posted by Msloggatt

I run the straight on a table saw & cut the mitre by hand with a japanese pull saw.. Sometimes istart the 45 with a Lion Mitre trimmer & finish off with a chisel Mike

Ditto on that
must be that long island training I had


the last one I did, I cheated
I butted the bead and quirk http://www.tools-for-woodworking.com...its/101493.gif

I will have to look for pictures of it but I looked nice on painted trim

[Gary Katz]

Phillip,
If you find those pics, will you send them to me? I won't tell anyone who did it. Promise.
Gary

[Gary Katz]

I finally found some time to play in my shop. Here's the jig I made, and the results.

http://www.garymkatz.com/TrimTechniq...k-MiterJig.htm

Jim, you were right, of course, there was some fuzzing on the outboard side of the cut. A sharp knife cut that off. Sandpaper might do it, too, but I was afraid of ruining/rounding the miter.

This was a pretty fast operation, really. A plunge router would have been a much much better way to go--less noise, less chatter, and probably a much smoother cut.

GAry

[Ohiobuilder]

Very nice Gary!