The Grid Jig

[damienhazo]

Ever since I extended the kitchen on my old man's sailing yacht, I've been interested in wooden grids. I tried making them back then and soon learned that accuracy is key. I've tried a few things since and had a system that was working but it still wasn't up to scratch. I gave it some thought and came up with this:

Damo's GRID JIG: (c) copyright / patents pending :rolleyes:
This is a 600 x 500 x 10 mm stainless steel plate that I had cut with an abrasive water cutter. I knocked up the specs in Corel and 3 days later the postie delivered it.
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The channels are exactly 22 mm wide and 10 mm apart. When using a 22 mm bush and a 12 mm straight flute bit, you get a grid with 20 mm holes. The equation is:
centre of channel = 22/2 = 11
outside edge of cut with a 12 mm bit = 12/2 = 6
11 - 6 = 5
+ steel 10 + 5 (next cut) = 20 mm
You can of course change bushes and flute bits to obtain varying sizes and strengths. The slots also allow for variation.


Depth = thickness of board/2 + thickness of template
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Centre punch ensures holes are accurate
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Away we go!
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An example of evenly-spaced channels
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Thread continues due to image constrictions.../

[damienhazo]

Moving the template is no problem. 2 existing holes and a new one on the end.
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Some variations for display purposes.
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The different channel sizes separated ready for sawing
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Sawing. Thickness = width of channel
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Some examples...
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The grid can be as big as you like. Additionally, turning the jig 45° enables diamond shaped grids.
The jig wasn't cheap. I think all up I paid around AUD500 with material, cutting and shipping. I intend to get a lifetime of use out of it so it was well worth it in my book. It doesn't have to be as big as the one I made so duplicating it would be cheaper. Would not recommend going under 600 mm in length though.

Damien
PS. Any darksiders who write that this is like dovetailing and should be done by hand should get a life. And an electric router - they're great mate!

[Bob Willson]

That is a great jig Damien.
I imagine that it would also be a relatively easy matter to make a similar one from square stock and weld it together then grind it all flat again.

Even making it in chipboard is an option; though of course, it would then not have the strength and it would not retain the exactness of yours

[damienhazo]

I imagine that it would also be a relatively easy matter to make a similar one from square stock and weld it together then grind it all flat again.

Thanks Bob. I considered welding one up but decided against it for 2 reasons:
1) Accuracy. The water cutting is 3/100mm accurate.
2) Heat warp. Abrasive water cutting is cold and doesn't warp the metal.

I'd be interested to hear from anyone who knocks one up another way...

Damien

[Chris Parks]

It could be done on a CNC controlled punch press but they are not exactly thick on the ground. The accuracy would be the same or very close to it, though the thickness is restricted.

[Bob Willson]

If you were going to CNC, then why would you go to a punch instead of a CNC router?

[Chris Parks]

If you were going to CNC, then why would you go to a punch instead of a CNC router?

To do the job in metal. You could do it with a CNC router with no template but not everyone has one of those either. Damo you need a CNC router.

[Bob38S]

Great looking jig - as usual Damien.

Seeing you like this sort of construction - have you discovered the company called "Trip Trap" - I think they are from Denmark - they make all sorts of [expensive] stuff using the grid idea. I managesd to get a cheaper version of a laundry basket using the same idea.
Regards,
Bob