# acme box joint jig



## SpotTheCat (Jan 29, 2012)

Here is a screw advanced box joint jig I made. I didn't want to take too much time or money making this, so I tried to minimize both, with time being more important. Here are the things I did to make this cheaper/easier to make.

1. I used 5/16×1" hex bolts throughout. The only thing glued on is the front face of the bearing assembly. Everything else is bolted/screwed in so I can adjust it if needed. I didn't have to re-make anything, despite the precision required in the final assembly.
2. I used the linear bearing setups from a couple of DIY CNC machines so I wouldn't have to worry about trying to get good sliding surfaces made out of wood. I'm also considering building a CNC machine, so I wanted some practice on this as well.
3. I didn't want a fully-box design, like the one at woodgears.ca, because I wanted to be able to process longer length stock.
4. Nearly all of it is made out of cheap MDF. I didn't want to waste BB plywood on something with questionable working-ness. I wanted to see how this material wears as a fixture material, too.

It works great! I use a spring to register each turn. It runs a 5/8-8 acme precision grade screw, so I can make fingers in increments of 1/16". It ended up costing $150 in materials. It could be made cheaper with better/local sourcing, but I bought most everything from mcmaster-carr for convenience.

Let me know if you guys have any questions!


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## 559dustdesigns (Sep 23, 2009)

Wow, this is a very impressive jig or machine. 
I can't wait to see what else you plan to share on Lumberjocks.
Keep up the great posts.


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