Stringing cutter for router plane *LINK*

Correction: cutter is 3/16" wide.

Derek Cohen (in Perth Australia)

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Re: Stringing cutter for router plane

Derek

>Looks good! Usually scrapers don't work as well with soft wood - glad yours does.

A question and a thought -

Have you tried it across the grain? Does it cut cleanly?

If you have trouble cross grain, I saw a similar cutter somewhere (kinda foggy in my brain as to where...) which had a curved bottom cutting edge - worked kinda like having nickers on the edge of the blade.

Re: Stringing cutter for router plane

Derek Cohen (in Perth Australia)

>Hi Derek (No folks, I'm not talkin' to myself!)

As you note, softwood is a real challenge for scrapers. I have had variable results. It's a little unpredictable at present, but it does perform better with a sharp cutter. The first picture below is cutting Pine with the grain.

Cross grain also tends to vary. On Karri or Blackbutt, both extremely hard Aussie woods, with short fibres, there is little tearout. On the Rock Maple sample (from earlier) there is considerable tearout. If one then knifes the line, the subsequent cut across the grain is easy and clean. Second picture demonstrates this.

I would love to see a picture of the rounded cutter you mention.

Keep in mind that this is a work in progress. All help greatfully accepted.

Regards from Perth

Derek (the other one!)

Re: Stringing cutter for router plane

Marc in Luxembourg

>Very clever! I could imagine a small profile, like a side bead for example, 'cause the Veritas router has a fence (as the Stanley too). You wouldn't need a beading tool. Great idea Derek!

Marc

Re: Stringing cutter for router plane

Derek

>Derek,

Thanks for the response. I think you have made a clever and unconventional router plane cutter.

The cutter I saw (from memory) would not give a perfecly flat bottomed grove - but that may be OK or you could use two - the first one to cut the initial grove and a second to level the bottom.

(From memory) it looked like it was formed using a small round file, round diamond hone, Dremel tool or a piece of drill rod with abrasive on it. Think of using the small round file to "refine" the bevel on your cutter. If you did that, the ouside corners would be lower than the center. The outside cutting edges would act like spurs - kind of like an upside down gouge used as a scraper. In fact, a vee shaped cut from a triangular file would do teh same thing but the buttom of the groove would be less flat.

It might or might not be worth the trouble. It might help a lot with curved or shaped grooves where it would be hard to knife the cuts (inside and outside) exactly where the router plane edges cut using the router fence.

It occurs to me that if you had 2 cutters (one flat and one shaped), the flat one would need to be exactly the same width as the curved one or a bit smaller would be OK - in fact probably safer. If larger, the edge of the cut might be ruined by the flat one but if smaller it would flatten the center of the groove after the initial cut with the shaped cutter.

Anyway - just an idea for you. I like your cutter idea.

Quirk router blades...

Scott Burr in rainy Ben Lomond,CA

>Are you thinking of these?

Re: Quirk router blades... another

William Duffield, on the Cohansey

>This photo of my Preston quirk router cutters (sold by Tony Murland) should give a better idea of their cutting geometry. The nickers cut first, followed by the router tooth blade.

The Preston has a side blade adjuster, thus the shape of the adjuster slot and the depth of the cutter. For cutting curved quirks or inlay stringing grooves, a shorter cutter would follow curves better, and be more adaptable to the typical router blade holding mechanism.

This is an old photo. The nickers on the widest cutter were not yet properly honed and were flat on the bottom. Use a small rattail file or a V profile slip to shape the nickers. The nickers are deeper than the cutter.

I don't see any serious problems with drilling, shaping and sharpening such a cutter from a cutter blank for a router with a #71 type mechanism. The hole between the nickers and the cutter would have to be smaller diameter, so chip clearance would have to be done a bit more often.