Thread: Joinery 'systems' get together (JSGT)

Back from family duties, a weekend away with the whole family, great time!
Returned today to the shed and the lock mitre joint jig. As soon as it got to 'usable' stage rather than 'finished', I cut a prototype joint and got a good joint..... first go!

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Looking at the geometry, if it is cut correctly, it should automatically result in a 90 degree joint so, when I glued this one, I left the joint to find its own angle .....

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.... and was very pleased to see this.
Now that I know the principle works, I'll finish the jig off but I need to include the provision to allow multiple cuts as, on workpieces thicker than about 12 mm, a single cut is removing too much timber for my liking?
fletty

EDIT, many apologies AGAIN, but the pictures have rotated during posting and I just can't stop it from happening. When you click on them, some rotate back, but change format!

Nicely done Alan....
Looking forward to seeing the finished jig over the prototype..
Cheers, Peter

Good job flettmeister! Looks like a nice clean joint too.

Immmm !!!!
Just following along but a big thanks guys for a prod.
Maybe I should re visit my lock mitre bits.
Assume like many I got frustrated early on
So it become a dust collector bit.

Cheers Matt

Looks like Timbecon will be getting some of my readies Probably get Kit #1

The jig is finished, trialled AND IT WORKS!
This is the fixed part of the jig...

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..... the front edge of this is the datum for all routing and the fence must be parallel to the front edge

The carriage to hold the horizontally machined workpieces.....

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..... consists of a base that slides along the front edge of the fixed base, a fixed cross bar which is square to the carriage and a toggle clamp to hold the workpiece like this....

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.... where the end of the workpiece is against the fence.
The carriage to hold the workpieces that are machined vertically...

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.... consists of a front face which must be square to its base and an adjustable slider.

To to set it up, I use the Infinity lock mitre gauge to adjust the height of the router bit and the location of the fence on the fixed base relative to the router bit. To machine the 'horizontal' workpieces, mount them to the carriage with the end against the fence on the fixed base making sure that the carriage is hard against the datum edge. As the workpiece goes past the cutter, the carriage ensures that the knife edge does not get crushed against the fence. The vertically machined workpiece is clamped onto the front face of the 'vertical' carriage making sure that its end is hard against the base of the fixed base and that it is square. Push the vertical carriage against the fence of the fixed base until the workpiece is hard against the fence and then lock the slider against the front edge (datum) of the fixed base. Once again, as the workpiece has passed the cutter, the carriage stops the knife edge from being crushed. The role of the slider is to allow the vertical carriage to be mounted (say) 6mm away from the fence on the first cut to reduce the amount of timber being removed per cut and to minimise tear out. A similar adjustment can be made on the horizontally cut workpiece by clamping it so that the end is (say) 6mm away from the fence on the first cut.
It is easier to do than my clumsy words above would suggest but the result is a joint like this on the first go....

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... and the ability to machine the joints on all 4 sides of a box in about 3 minutes!

fletty

Sold to the guy driving home for $2

Looks great

DaveTTC
The Turning Cowboy
Turning Wood Into Art

That's pretty nifty.

As a relative newcomer to these sorts of things, I think the take home message for me is about being creative and realizing that the reference surfaces/datums (data?) don't need to be close to the business end of the board - just as long as they are suitably parallel/square/whatever.

Iain

I was disappointed not to be able to make this gtg but I was overseas at the time.

Sent from my SM-G935F using Tapatalk

Excellent write up and description. Was only able to take a quick look at the pics earlier.

You'd think they would suggest a set up along these lines with the bits (bracing myself for a hit over the head with a link where soneone says 'they do')

DaveTTC
The Turning Cowboy
Turning Wood Into Art

Thanks for the write up and photos. SWMBO asked me what I was reading so I showed her. She rolled her eyes and said/asked/declared "another Jig?!"

I found that both the horizontal and vertical jigs were resulting in too much tear out where the router bit left the workpiece and so I decided to find a way to include a sacrificial backing piece to protect the workpiece. Also, being sensitive to the effect of spinning router bits on fingers, I decided to better protect my fingers as well. I've found a temporary fix for the vertical jig but got a bit 'sophisticated' with the horizontal.
This was the starting point...

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..... and, after an hours fiddling, this is the final result...

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.... with a sacrificial backing piece that can be slid forward and recut for a different setup/thickness and 2 hand grips to keep my fingers away from the cutter.

With both the workpiece and backing board extended to the fence...

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.... after passing the router bit, the workpiece now has little or no break out and the backing board of course is shaped to support all subsequent pieces...

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I also now have much better control of the jig via the 2 handles than I did by just grabbing it where I could..... and shutting my eyes!
fletty

It was a luverly rainy day here and that means SHED TIME!
I used the lock mitre jig in anger for the first time and made 2 very basic boxes with lock mitre corners and rebated floating lids and bases.

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Basically, even though set up time is greatly reduced, it looks like I can make a single such box in 40 minutes or 25 minutes each in a batch of 4? I know this isn't in the spirit of fine box making and that each box should be a single creative exercise BUT every now and then ...... quantity replaces quality?

EDIT; I really am getting frustrated with my pictures rotating during posting but, as I don't hear of anyone else having the problem at the moment, then I presume it is something that I am doing? I take the pictures on my mobile (no rotation occurs), I email to myself to reduce file size (no rotation), I 'receive' the email on my iPad (no rotation), I compose the post using the picture icon at the top of the draft (no rotation), I post (ROTATION!). I note in the new instructions for posting pics in MARKETPLACE that the MANAGE PICTURES method is recommended and there is a reference to possible issues with mobile devices? Next time one of my shed regulars drop in, could you please show me how YOU do it?

fletty

The picture problem is not just you Alan, it was thought the problem was caused due to posting from an Iphone but don't take my word for that as I have had the same issue posting from a desk top PC.