Sewing Table #3: Using the Mortising Machine (for the first time)

oh, wow that answers some questions, you are going to town with this sewing table. I hope my wife is not seeing this, I need to finish the house before she gets her quilting furniture.

-- http://www.twinoaksgrowers.com

Here is a tip for you Blake.

The mortise chisels straight from the box are sharp, but they could be sharper. I polish/hone the 4 outside edges of the of the chisel on my tormek. There is a huge difference in the ease of cutting. I also noticed discolouring of the cutting edge due to heat, but after honing it remains perfect mirror finish and runs cooler.
(My chisel dropped from the chuck whilst in the installation process – gravity over 6”, my finger underneath and a neat square cut into my left index finger down to the bone – the chisel was sharp at least)

Watch the spacing between the auger and the chisel – this makes a big difference in the performance, I find about 2 to 2.5 mm spacing works for me.

The mortise chisel is well known for clogging inside the chisel – try taking lighter cuts, especially during the first full plunge. Ensure that the waste material can escape.

Hope this helps you a little

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

Thanks Tony!

I’m open to as much mortising machine advice as you folks can give me. Keep it coming!

-- Check out my new website! http://www.theeasellife.com

cool Blake, this is coming along great. my favorite part of any project is the glue up because you see everything come together and i can’t wait to see this one come together!

Blake their are diamond hones for the inside of the chisles. They are available from Rockler i believe. Around $20.00. I mount the cones in a drill press to none the inside of the chisles.

When you chuck the drill and chisel into the mortise machine leave about a gap of a nickle above the shoulder of the Chisel. Lock in the drill tight against the chisle and then loosen the chisle and move it up tight to the machine. That will give the required clearance.

Here is Mark DeCou’s blog on Mortise machines.

-- Karson Southern Delaware karson_morrison@bigfoot.com

Bake – I think you need to swing your bit around so that the opening is to the side. That will cut down on the clogging. If the opening is toward the front or back of your cut the chips have no where to go but into the body of the bit, where it will clog and eventually stop the bit altogether. Turn it sideways, towards the open portion of the mortise and it won’t clog so much.

-- Betsy - GO BUCKS!

Very nice work.

-- CJIII Future cabinetmaker

Blake,

You are doing great!!!

I wrote this short post on Tuning a Hollow Mortise Chisel (Episode 7a.) on my blog some time ago. As others have pointed out, it helps to have really sharp chisels! One of the most useful items I have found to do the tuning is the conical sharpening kit, which does a terrific job of sharpening the inside surfaces of the chisels.

-- Al Navas, St Joseph, MO, http://sandal-woodsblog.com

Thanks for the tips!

-- Check out my new website! http://www.theeasellife.com

The only advice I can give you is to not be shy about having a lot of drill bit sticking out. When I first got mine I tried to set it perfectly and over heated the bit. Looks ugly now. :-)

-- Gary, East TX -- The longest journey begins with a single step.

All above suggestions are great…

I’ll reiterate the importance of sharp chisels! Honing the four outside faces and honing the inside with a cone is a must. Also, sharpening the actual bit should be done with an auger bit file. You’ll get really good results if all aspects are well tuned.

I second or third the notion of leaving a ton of room between the bit and the chisel. More is more. Less stinks, or would that be sticks…

One other thing about the mortiser. You’ll want to be sure that you take out as much slop as possible from the ways. This is adjustable. You should have little to no play in the dovetailed ways.

Keep it up!

Here’s a link to a Roland Joihnson FWW video on the topic, if you have access to it…

-- Dorje (pronounced "door-jay"), Seattle, WA

My tips.

1. square the chisel to the fence by bringing the chisel down to the actual work piece/ fence/ or square scrap) while loose, then tighten
2. At class we set the spacing with a dime (between the auger and the chisel)
3. On your first cut go slow, on move the cut 1/2 a chisel step over. This way you cut half into wood and half into air. This helps to minimize the chisel from twisting and giving you diamond shaped cuts as you showed above.

Good luck.

-- -John "Do I have to keep typing a smiley? Just assume it's a joke." www.flickr.com/photos/gizmodyne