57 minutes ago, Smallpatch said:

Did I also mention it has a 5 or 6 hundred dollar factory cart under it. You could put a motor on it and drive it home.

Does it have a trailer hitch on it?   I've got 2" and 2 5/8" balls and will buy 1 7/8" if needed.

 

I have a friend with a Domino who loves it.   I'm convinced that a lot of people who shell out for Festool love them as rationalization for spending that much money.  They don't always come in top rated in independent reviews.

I priced the PM benchtop morticer at Amazon. $499.99. Just saying 

I picked up a couple of Fine Woodworking Magazines at the library last week.  Interesting, one had an article on tenon strength.

 

Results:

- Width of mortise is most important, going from 1.25" to 2.25" more than doubled breaking strength

- Depth is second importance,  every 1/4" increase in length added 130 - 180  lb of load bearing capacity

- Thickness of tenon less importance, going from 1/4 to 3/8 or 3/8 to 1/2 added 40%

 

Applying glue to both mortise and tenon increased strength by 103% over just tenon.

 

0.005" gap is best - should be able to insert almost all the way by hand, but not fall out with gravity.

 

 

Next issue was an article on router guide bearings and he showed  a jig for tenoning.   I'd forgotten I'd made a similar one about 10 years ago and only used a couple of times.   I made it to center a mortise on a 3/4" stock -- I figured that would be the 80% case.  Put on a fence for one of my routers and routed some 3/4" slots.   Lined them up with the base and attached.   Grooves on bottom for clamping on piece to be routed.  Hmmm.   Have to reconsider this.  One time I did an offset mortise, I simply added a shim to the fence..

way to go Keith...

That's the ticket, Keith. 

Great discussion.   Thanks, guys.

 

And another approach that came in my inbox this morning.

 

 

 

Here is another mortising method. Not necessarily better but interesting, nonetheless. He uses a router table. 

Caveat, the first half is about deep mortising. The rest is about hinge mortising.

 

43 minutes ago, Gene Howe said:

Here is another mortising method. Not necessarily better but interesting, nonetheless. He uses a router table. 

Caveat, the first half is about deep mortising. The rest is about hinge mortising.

 

 

I think I've concluded that "perfect centering" is overkill.  It's unlikely that your stock is exactly 0.750" thick.  I prefer to measure from a "reference surface," e.g., the show side.   Like this guy, I use my mortises to set my tenon offsets and likewise reference from one reference surface and not worry about perfect centering.  It's all pretty much moot if you have a tenon that's inset from the surface like on chair legs, table legs,  stretchers, etc.  Just the way I swing.

 

Not too fond of his free-hand plunge route -- a little to close with the hands for my comfort.

 

 

Love the Aussie accent.   For a while I had an Australian boss (as was his boss) , a kiwi on my team, and my team worked closely with a team in Sydney.  https://www.amazon.com/Blokes-Sheds-photography-Julie-Hopkins/dp/1869502787

 

Edited September 11, 20178 yr by kmealy

26 minutes ago, kmealy said:

Not too fond of his free-hand plunge route -- a little to close with the hands for my comfort.

Guess it depends on the width of the stock. I try to never have my fingers close to the cut. Vertically and horizontally.

Stick, I just now read all the post and answers in Keith's original post and you asked and yes I did buy this Powermatic from an auction. A school systems trade school. The equipment was here in Breckenridge where I live along with two or three other towns but all the equipment all went to Sweetwater, Tx  for inspection and pickup. I talked to the directors before going to look at the items and they said just look over the things and you  can tell most of the things were never used. We didn't have any students so we had to close down. Money was too tight to sit and wait until word of mouth and what little advertising they could afford could get enough people in to keep the doors open. I also bought a Dewalt 788 at the same time. It was also new. I really don't care to sell it but I did put a price on it.  Convience of having everything I need  is important to me and I don't have to some in the house and grip I don't have a certain tool to do a good job on this job. Something I could not do when working for a living...

  A trade school in small schools being run in the day time instead of night after peoples regular jobs just don't work....A job to pay the bills has to come first but they could not get enough teachers to do the night work.

YAM (yet another method) http://www.finewoodworking.com/2015/05/27/how-to-cut-mortises-with-a-plunge-router

Now, that is one slick jig. 

Thanks, Keith.

Another build for a winter's day! Thanks, Keith.

John

I built some dining room chairs out of WOOD magazine from a few years back. Tons of mortises they did them using a drill first then squared em off with chisels. I didn't like the prospect of repeating that over and over. I opted to cut them with a router and a template. I made one template for the back legs and another for the front legs. I cut the templates using a half inch bit then mounted a 1/2" guide bushing with a 1/4" bit to cut the slots. Just clamp the legs to the template make a few passes, flip the leg cut the slots on the other face and move on to the next leg.  I used a spiral upcut bit and was working with cherry, no real issues with burning, just take 1/4" deep passes and dont let it rest in one spot too long.

And we're not going to get into "angled mortises vs. angled tenons" are we???

1 hour ago, kmealy said:

And we're not going to get into "angled mortises vs. angled tenons" are we???

I've cut a number of those. Never on purpose, though.

https://paulsellers.com/2017/05/re-easy-angled-tenons-article-fine-woodworking/

 

 

As for my tenons I cut those on the TS then pared them round with a sharp chisel. You could cut angled mortises by shimming the jig base at an angle and using a long bit.

Well, I decided to get a solid carbide router bit for mortising.   10% off through today at MLCS

 

http://myemail.constantcontact.com/10--OFF-Solid-Carbide-Spiral-Bits-for-Smooth-Cuts--with-code-.html?soid=1101532755223&aid=VG_nlBW-b4Y

I never understood exactly why, but Pat Warner was never a fan of the spiral bits. I absolutely love them for all sorts of use, but they really shine on mortises.