Thread: Metric hollow mortiser bits

I checked my usual European retail outlets and found nothing so looked a little deeper.

Fisch make both metric and "customary unit" hollow chisel morticing bits 0382 Mortise Chisel Sets 2 pieces / Mortise Bits/Mortise Chisels / Drills & Countersinks / Products / Home - Fisch-Tools
Technical details http://www.fisch-tools.com/en/conten...talog+2016.pdf
Contact details are on the first link -- you may need to be sitting down when you get the price.


If Fisch doesn't sell direct to the public -- refunding 20% VAT can be a pain -- if you ask nicely Euro suppliers will normally recommend a retailer who will export outside the EU.


Colt also do metric Hollow Chisel mortising bits http://colt-tools.com/projects/32/images/cata_old.pdf page 39
again expensive and finding a retailer might be a linguistic challenge.


Before going overboard and ordering a complete set, a couple of points.
In my experience 1/2" is the practical maximum for a bench top morticer.
5/16" is so close to 8MM as to make no difference.
"Normal practice" would be to standardise on a limited number of mortise sizes.

The only time you really need the mortice to be a particular size is in frame and panel work where the groove for the panel should be the same size as the mortice used to attach the rails to the styles. The rest of the time, a "customary unit" mortice (1/4", 3/8" 1/2") will happily do the job.


and, with hollow chisel mortices, cheap chisels in Aust hardwood is a recipe for tears.
I've not used the Japanese pattern hollow chisels, but note that according to the blurb they are optimised for softer wood.

You're looking at it all wrong. There are plenty of metric sets for sale. They contain 6.35mm, 9.525mm, 12.7mm and 19.05mm bits. Cut your mortises and pare the tennons to fit.
Rather than spending a small fortune on metric bits, lash out and buy a nice mortise gauge. Takes the guess work out of the lay out.

Originally Posted by ian

The only time you really need the mortice to be a particular size is in frame and panel work where the groove for the panel should be the same size as the mortice used to attach the rails to the styles. The rest of the time, a "customary unit" mortice (1/4", 3/8" 1/2") will happily do the job.

This.

These three (3) sizes will cover most of what you need and even then for larger sizes, you can always go over the mortise to align with the size you want.

I have done this successfully, and it works particularly well in Eucalyptus.

Thank you to everyone for this information

Seems I was overthinking it a bit - and, in fact, then most people are using imperial bits.

Good to know, and many thanks for sharing the wisdom!

Nakahashi is the the maker of Star M brand and they do make a British pattern set in mm

Nakahashi Seisakusho Co.,Ltd

the Star M brand is the one that both Smchmidt's and bobby at woodworker tools works and lee valley sale as high grade Japanese pattern bits. It is the same company and these bits have been made for some 50 odd years by them. as to there web site " the star M are described as "Standard line up" with this build


Manufactured from the finest and select Japanese carbon steel best suited for these tools.
The original Japanese Pattern Disign. Chisels have finely polished cutting blades with sharp pointed and releaved inside corners for stress free clean cutting. The bits have a brad point, one cutting lip and one spur for straight cutting and superb chip ejection.
Conbination of material, design and craftmanship ensures superior performance in soft and hard woods.
Complete specifications to fit most chisel morticers in the world market.
Complete size coverage (3mm to 36mm) to ensure that entire user needs are met.
These best performing tools have been imitated thoughout the world, but never been duplicated in performance.


yes you read that right 3mm!!!! I have one