Finn M39 "Finger" splice anatomy

[WarPig1976]

I did this stock for a fellow a few months back and wanted to share photos because you just don't see pics of these things taken apart, but I forgot. I always forget to take before photos too....
As you can see there's nothing complex going on inside. Just straight cuts with a very large router bit.
As I found out from Internet experts on another forum people have fantasies about these splices being complex internally and nearly impossible to take apart without damaging the stock. I of course already knew otherwise and had it apart in about 10 minutes without any additional damage.
The present owner attempted to repair the failing joint himself. Failing in the attempt he tried in vain to separate the stock which caused further damage to the edges of the fingers. I should note I did no finish work at all, only oiling after the fact. All in all it came out nice me thinks.
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[Vincent]

Another nice job.

[CINDERS]

Outstanding

[HOOKED ON HISTORY]

I have never used a router. How are the uniform tapers accomplished? Perhaps I could try this on my 1891 stock restoration project.

[WarPig1976]

How are the uniform tapers accomplished?

Picture a large disk with finger like cutters. You feed the piece in from a jig that holds everything square until you reach your depth of cut.
Router probably isn't the right description. A dedicated milling machine is more like it. It's a very complex operation if you consider the two joined pieces have to come out to an exact measurement.
Without a large expensive custom made cutter. A dedicated machine to spin it and jigs that have been well thought out it's just impractical to try and replicate today.


Here's a video of a finger joint cutter on a small scale
.

[HOOKED ON HISTORY]

So more like a tapered cutting disk fed the work to a depth & angle controlled by a jig.
I would love to see a photo of the device if you stumble across one. I have always wondered at those joints.
Great post.

[WarPig1976]

I did see a picture once of what I believe was a Finn Armorer doing one online but I can't find it for the life of me.

[HOOKED ON HISTORY]

That video is essentially the picture I had in my head.
I wish I had chosen wood working as a carrier. The ingenuity & artistry involved is completely amazing to me.

[CINDERS]

How good were the artisans in the 17th & 18 century making stuff by hand you see stuff like Chippendale and say violins by Stradivarius and marvel at how beautifully hand built they were just amazing.

[WarPig1976]

It's the antique engraved and inlayed firearms and clocks that fascinate me. The perfect melding of wood and metal.