Mortising Machine Options

Woodworkers discuss the pros and cons of various types of mortising equipment. November 28, 2006

We are using a World War II era chisel mortiser, which takes forever. Any recommendations on what to replace this with to speed up our production? We mortise doors for fishplates, mostly.

Forum Responses
(WOODnetWORK Forum)
From contributor L:
An oscillating mortise cutter such as what MAKA makes would be just the thing for you, if you can afford 15K new. What is a fishplate?

From contributor D:
Ditto on the fishplate? And ditto on the Maka. They are no longer being made, so used is all you will find - check on Ex-Factory. Larick and Larick make a new type oscillating chisel mortiser - very nice, but expensive. Depending upon the mysterious fishplate, a horizontal slot mortiser may be adequate if you are mortising for Euro style hardware. Slot mortisers run from Grizzly to Felder and Panhans, with quality and durability reflected in the pricing.

From contributor S:
As you've already invested in square chisel tooling, look for a secondhand Wadkin DM/V chisel mortiser. This is like a much bigger, heavier (all cast iron) floor-standing version of the familiar Multico/Delta pattern chisel mortiser, but it has a vibrating head (really!) and cuts through oak like butter.

From the original questioner:
Sorry maybe "fishplate" is not the correct term. In the Caribbean, that is what we call a loose tenon! Thanks for the info.

I was told that a chain mortiser is the ideal machine for speeding up my production. The theory makes sense, but these types of mortisers seem to be becoming obsolete. Any alternatives?

From contributor D:
Thanks for the fish plate explanation - I was having a hard time filling in that blank. I was picturing some poor fish stuffed into a mortise or similar illogical use.

As for loose tenons and chain mortisers, I know a bit about both. The problem with loose tenons is that half your cutting is dead into end grain, and is difficult at best. Chain mortisers can be ground a bit differently, but they are designed to cut long grain mortises in stiles, not end grain. The other problem is that the loose tenon is a third piece in what has traditionally been a two piece joint. Twice as much (difficult) cutting, and twice as much wood to wood to glue. The available equipment, as evolved historically, is designed to make the two piece mortise and tenon joint, albeit with two different machines.

If you are committed to that fishy tenon, then a spiral cutter in a horizontal slot mortising machine will make things better and easier than a chain mortiser. Or oscillating chisel mortisers will crank it up a couple of notches, but have a hard time on end grain (teak in particular).

Chain mortisers tend to be seen only as antiques, with the imported machines (Mafell, etc.) brought in for sale to timber framers that take them from mortise to mortise, and all in long grain.

From contributor R:
Never heard the term "fishplate" before. Horizontal slot mortiser is one way to go. We just turned down a three head Maka for doing full size doors. Makas are still being made, but can't recall by who at the moment. Invicta, Paolini, Griggio and many others make slot mortisers. Can't say enough good things about slot mortisers. Been using one for 20 years and have used all the other types, such as chisel and chain mortisers.