Would like advice on how to cut this piece

[andrew whicker]

Hi all,

I have a joint that I'm trying to bolster with some steel. I am laminating 3 pieces of wood that are ~5" wide and ~7/8" or 3/4" thick into pieces that are 2.25" to 2.5" thick. The boards are currently closer to 7/8". Besides the point really.

I'm trying to put a piece of steel on the inside of the curve of the joint. I'd like to have a piece of steel water jet cut and then slip into a pre-cut slot. I can make the slots in the straight pieces before glue up easy enough. I was hoping that I could cut the slot in the elbow after glue up of the elbow, but I can't think of how. Router doesn't seem possible, table saw doesn't seem possible. I can laminate a piece in the middle with the curve. Otherwise, I can't think of anything.

Curious if you guys and gals have any ideas.

idea in autocad. Dotted line is hidden line, this shows the piece of steel that I want to install.
elbow with slot_autocad.jpg

Elbow. The black portion needs to be cut out.
elbow with slot dimensions.jpg

Elbow without dimensions:
elbow with slot.jpg

the elbow by itself (vertical leg and horizontal leg are not installed / glued up). This one is a bit different, I've made some changes. More or less the idea though. I'm going to make the elbow bridle joints 'female' though. Haven't re-drawn it yet.
elbow with male.jpg

You can see some pieces here (at the bottom of the photo) that are glued up. Also included a photo of the glue up. Hope this helps give you a clear idea. Let me know if you have questions.
IMG_20180317_231829_279.jpg

IMG_20180318_170835.jpg


Cheers and thanks.

[Ken Fitzgerald]

I'd use a router with a slot cutting bit.

[Simon Jones]

Have you considered making the curve in pieces of laminate before the glue up? If the slot is narrower than the center piece, make a layer the height of the slot and route the curve into that, then build up layers on either side to fit. You would want to leave the glue line clear but shouldn’t be too much of a problem.

[andrew whicker]

sorry, I guess I didn't dimension the height of the slot = 2". A bit big for a slot cutter on the router (as far as I know).

I'm guessing that my only option is to do a lamination trick. Curious if there are cutting options. I was going to raise the table saw blade up to it, but the blade doesn't raise high enough.

(Edit: I haven't glued the elbows up yet.)

[andrew whicker]

I guess the other option is to have a proper wood shop use their shaper (?). I'm pretty open to sub'ing things out, but I'd like to have control of this one. I want it right on center.

[andy bessette]

When designing a joint you must consider, first, how it would be produced. It is folly to get carried away with Autocad, sketching something that cannot be built. Only experience actually building things will enable you to come up with a practical design.

To solicit help in this you must be willing and able to share much more than you have. What purpose is the steel part? How can you expect to fasten it to the surrounding wood? Etc...

[andrew whicker]

I want the steel to act as a structural element. Plan on using t-nuts or sleeve nuts in probably 4 places along the length and epoxy to capture it.

That's why I'm here, to see how you would do it. I know I can laminate it, I'm wondering if I can cut it out. I have other design ideas too. I haven't committed to anything I can't build yet....

[Wayne Lomman]

It really needs to be done out of 2 pieces rather than three. This would allow you to rebate half the groove in each piece before gluing. Since you already have the 7/8 stock, you may have to go to 4 thinner layers to make it work. I would want to be able to glue the steel spine in place at the same time as the main glue up. I think this is the most feasible way to do it if I understand your machinery availability. I would be quite confident that it won't fall apart down the track. Use epoxy glue.

Alternatively, it could be done on a shaper using a slotting cutter provided a reasonable jig was made to ease the cutter into and out of the piece. Cheers

[Rich Engelhardt]

Wrox and Dremel & a couple/few others make a small diameter plunge saw ~ 4". Just make a jig that hold it captive and have at it.

https://www.worx.com/power-tools/saw...aw-wx429l.html


I used the Rockwell version & it's really a slick little saw.

First good battery one I see is going home with me. They are small, but, they cut big!

[andrew whicker]

Yeah, I think you're right.


Getting some water jet cutting quotes now.