Finger Joint Jig

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Phazor
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Finger Joint Jig

Post by Phazor »

I'm building a cabinet for a 63 vibroverb. I talked to my brother about doing it out of pine with finger joints. He is very good with tools and researched the internet and came up with this jig for a table saw using 3/8 x 1/16 all thread.

It's so cool you clamp the boards in it and run thru the 1/4" dato blade and then turn the all thread handle 8 click/rotations and you cut 1/2" down the edge till you have completed the 1/4" finger joints. I'm so lucky to have him for a brother. He's also a drummer. We jam on sundays.

Ed Stiles is where the design of the Jig came from if anyone is interested. https://www.youtube.com/watch?v=JYxDXHGRRrk
Attachments
You see a cam on the all thread that clatters 8 times to move boards horizontal down 1/16" per click
You see a cam on the all thread that clatters 8 times to move boards horizontal down 1/16" per click
The boards are placed not glued to check for size and square.  top and bottom need trimmed before gluing
The boards are placed not glued to check for size and square. top and bottom need trimmed before gluing
these are sides clamped in place on the jig
these are sides clamped in place on the jig
Last edited by Phazor on Wed Jan 21, 2015 3:57 pm, edited 1 time in total.
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cbass
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Re: Finger Joint Jig

Post by cbass »

Nice jig! Adjustable Lots fancier than mine.
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Phil_S
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Re: Finger Joint Jig

Post by Phil_S »

This is really very cool and I like it. I'd like it even better if I had a table saw and a place to put a table saw. You can do all sorts of things with a nice table saw like that. I know that DIY success feeling just can't be beat.

Not meaning to be critical here, but just wondering is why you'd choose to do that with the table saw. That's a seemingly huge jig for a relatively small piece. Sure, there is always more than one way to do things. My first instinct is to cut a box joint with a router. You can buy a really nice jig for about $80, maybe less. Maybe that's because I don't have a saw, and I can take my router outside to do this. And maybe you don't have a router? I'm thinking anyone with a saw like that should also have a router!

In any case, nice work and congratulations on a job well done!
Phazor
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Re: Finger Joint Jig

Post by Phazor »

Jerome is a machinist. There is a router table behind another saw in the back. On this jig, you can clamp 4 boards in place and do all sides at once if you offset 2 sides. The size of it forces it to lock into both channels of the table saw and keeps it true. If you have the gear why not. He has metal lathes milling machines, drill presses, grinders planers and is a great welder. Anyway its his thing. He was just helping me out. He loves building things.

Also he needs a tool intervention. I need an audio intervention. :D

I have 2 old fender amps chassis I found in pieces. I put into head cab years ago and use with external speakers. We just decided to build pine combo cabinet for them finally. They are both vibroverbs. 1 black 1 brown.
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Structo
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Re: Finger Joint Jig

Post by Structo »

Nice sled!

One day when I grow up I want to make cabs.
Tom

Don't let that smoke out!
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Cantplay
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Re: Finger Joint Jig

Post by Cantplay »

The great thing about this design is that there us no cumulative leapfrog error that can mess you up on a long joint.

On pine you have to go a little sloppy because it swells so much when you apply glue.

John
Do not limit yourself to what others think is reasonable or possible.

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Phil_S
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Re: Finger Joint Jig

Post by Phil_S »

I hadn't realized you could do all 4 board in one pass. That makes it almost magic. I see the light!

Even the good half blind dovetail jigs only do 2 boards at a time.
R.G.
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Re: Finger Joint Jig

Post by R.G. »

Looks like a variant of "Lynn's Jig".

That's the first place I saw a threaded rod used for indexing boards to cut finger joints in all-in-one.

This one has had some cleanup and refinement from the original Lynn's version.
Phazor
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Re: Finger Joint Jig

Post by Phazor »

PostPosted: Sun Jan 11, 2015 12:31 am Post subject:
On pine you have to go a little sloppy because it swells so much when you apply glue.
I remember reading about the joints swelling from the glue and getting tight on the TAG forum somewhere. My Brother and I each brushed the glue on an opposing edge and popped it together to keep the joints from swelling on us. It went together pretty fast and we did not have that to tight problem.
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Finger Joint glue.jpg
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cbass
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Re: Finger Joint Jig

Post by cbass »

Much fancier than mine I just use and index .pin. Lifting all the sides together about 50 times for the 2x12 cab i built made from ¾ ply gets a perty good forearm workout.
You are lucky my brother just drinks all my booz steals my drugs and makes lewd comments at inappropriate times or is that me ? I get mixed up sometimes
boots
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Re: Finger Joint Jig

Post by boots »

That's a slick looking jig. I just got the finger joint template for my router and it works great - makes perfect joints every time (after the learning curve). I've done it with the index pin on the table saw, and I think the router is much easier and you don't get the cumulative error if you mess one up.

As someone mentioned, gluing up is the hardest part. I have tried applying glue with an old toothbrush, foam paint brush, my finger, etc., and still not happy with how time consuming it is to apply glue. It's always a race against the clock.
Don't you boys know any NICE songs?
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cbass
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Re: Finger Joint Jig

Post by cbass »

Naw table saw is way easier and faster once you get the jig setup . you gots to have a decent dado blade . once your jig is made the only setup is putting on a dado and adjusting the height.
That said I'll never build a cab with finger joints again anyway glue lock bits are the way to go. Dont have to worry about tearout and strong as fuck.Hell glue and pocket screws makes a really strong joint with minimal tools
Phazor
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Re: Finger Joint Jig

Post by Phazor »

I used a spline across 45 joints with a dato baffle in other spk cabs I have. I used these cabs for 30 years and never had one come apart. I just had these 2 old fenders and my mission was to build period correct pine cabs for these 2 amps. The Jig makes it very easy to make these joints. If my brother was not involved with his tools and skills, I'm not sure I would try buiding the box joints.
Attachments
edges sanded.  next cut the angle for the chassis
edges sanded. next cut the angle for the chassis
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Phil_S
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Re: Finger Joint Jig

Post by Phil_S »

Really, you should sell knock down pine cabs on eBay. You can ship in a flat box just about anywhere. You can make some decent spare change on this, but don't quit your day job. I feel certain there's a market. I'll bet 1x12, 1x10, 2x12, and 2x10 will fly off the shelves. 4x12 and 4x10 will be large and cost more to ship, which will depress the market for those.
Phazor
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Re: Finger Joint Jig

Post by Phazor »

Hey Phil I was thinking about the flat pack cabs. Not sure if I would want to run a business but I'm still think'.
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