Blind finger joints flat on table... Box drawings...

[jeff_albro]

I have came up with a way of doing blind finger joints with the parts flat on the table. It will look like a stepped rabbet joint on the outside, but give you lots of gluing area and vertical registration. It will show 1/2 circles on the inside of the corners.

I'd test this myself, but I don't have a CNC machine.

I've made up drawings that will make parts for a the sides of a simple box. You'll just need to use a table saw to run dadoes and cut plywood to size for the top and bottom.

The drawings are for 3/4" solid wood with a 1/4" bit. The finger cuts are 1/2" deep, as the layer name suggests. I have not added any extra clearance between the fingers for assembly. I figure that a .250 bit probably cuts a .252 or so path, enough clearance for assembly. If not, please let me know and I will adjust the drawings.

You can get those drawings at:

http://velvet.antistatic.com/~jeff/shopbot/finger-joint-box.dwg

and

http://velvet.antistatic.com/~jeff/shopbot/finger-joint-box.dxf

Has anyone seen or made this type of joint before?

If not, would someone be willing to try it out for me?

If it is a new joint, then I may do further research and look into filing a patent. (Which, by publishing this idea now, means I will have one year to file.)

If it is an old idea, then I hope someone finds the box plans useful!

Thanks!

-Jeff

jeff@antistatic.com (mailto:jeff@antistatic.com)

[robtown]

I kind of glanced it over, I'll take some time with it later, but the inherent problem with trying to cut 90 degree joints out of flat stock like that is that the fingers have square edges while the router bit leaves a radius in the corners of inside cuts.

[bill.young]

Hey Jeff,

That's the way that the corner joint works in the boxmaker module for the Project Wizard, though we don't run the fingers and slots all the way across the width of the joint. We also cut the fingers and slots back a little bit so that the slots don't show on the inside.

You can see a rendering of the joint at the bottom of http://www.shopbottools.com/projectwizard.htm and download a beta of the Project Wizard to look at the output files (or cut a box for those who have a ShopBot).

Bill

[jeff_albro]

Rob - Yeah, that's why I need to push the end of the finger cut into the inside of the box, so that the perpendicular piece doesn't interfere when assembled.

Bill - I can't see how you deal with the radius issue in the rendering. Do you hide it in one of the steps? I'll download the software tonight and take a look at the file.

PS - I love the part wizard idea! I'd love to hear more about how to design for it.

Thanks!

-Jeff

[kivimagi]

Bill,

The link for project wizard seems to be down. Are you able to restore, or should Nancy be notified?

Regards,

[bill.young]

Hey Jeff,

There's a picture ( I hope! ) with more detail. I cut 1/8" off of the top of the fingers (the radius of the bit) and make the slots just long enough that they don't show on the inside...that leaves a little half-round hollow section at the end of the slot for glue squeeze-out.


2498



I know that some of y'all have heard this for a while now, but we'll have a new Project Wizard beta out soon and are working on a developers kit to make the process of creating projects easier. We'll post something and send off emails to folks that have shown interest as soon as it's ready.

Bill

[jeff_albro]

Bill - I understand now. Thanks!

So, I guess it was an old idea : )

Still, if anyone wants to make boxes based on my drawings, go for it.

-Jeff

[bill.young]

Hey Ryan,

I just tried it and it seems to be working OK now so give it another shot. If you can't get it to work let me know and I'll see what I can do.

[gerald_d]

Anybody else dislike these upside-down parts of the Forum where the latest post is on top?

[don_ask]

Yes, I don't like this new method either. Maybe, I just don't like change. I will give it some time and then comment some more!

[gerald_d]

Most of the Forum is still the conventional top_down_to_bottom, but this "Project Ideas" section (at minimum) is the other way around.

It is very easy to find the bottom of a thread - just use the "End" button. The "Home" button takes you to the top.

[slendon]

Much prefer the latest post at the bottom..seems logical like all other written matter.

Steve

[daveiannone]

well....If you just want to read the posts then the new way has you there as soon as you click the link.....BUT if you want to post then you have to go to the bottom anyway.....Makes no difference to me...but I WOULD like to see them ALL the same...
Dave

[beacon14]

I second the vote for ALL the same.

[Brady Watson]

Yes...Please put it back the way it was. I was sitting here wondering what was going on and how my post wound up above previous posts...

No other board I have seen on the web does it this way. It's natural to start at the top and work your way down a conversation.

-Brady

[cnc_works]

Please...leave the newest post at the bottom.

My vote.

Donn

[bleeth]

New posts at bottom are pretty universal in groups-if it ain't broke don't fix it.

[gerald_d]

Project Ideas has some very long, slow loading, threads. (As do some other topics as well). This upside-down format allows you to read the latest post while the rest of the thread is still loading.

However, IMHO the better way of dealing with long threads is to switch on the "Auto-Archive" feature so that (for example) the first 20 posts are filed away whenever the thread is 30 posts long. (Here (http://support.discusware.com/forum/messages/7/17027.html?1061382302) is an example - you can see the archived pages right at the top)

Generally, if the board must be upside-down, than ALL sections must be upside down, and the "add new message box" must be at the top.