box joint and jig question and advice sought

[roy labeau]

Hello all, first post...

I searched my question and found a "nearly" adequate answer from a thread here dated 2009. I would like to revisit the problem and ask for some more specific answers.

The problem I'm needing help with is related to making box joints on long pieces of material. It is somewhat of a two part dilemma, in that I would like to know how you would tackle this venture, and can you advise on what I'm thinking I will do. I will be box jointing 1x16"x72" pieces. I do not like the idea of doing them on the TS due to the size (not just length), not to mention the lack of headroom in the shop.

What do you think about using a dovetail/boxjoint jig and turning it 90 degrees and using a handheld router sideways? This would allow me to keep the boards flat on the bench. Leigh did not like this idea one bit and would not recommend it lol. Was looking at their R9 Plus jig.

Short of working off a step ladder (from the old post in 2009), how am I going to best box joint 6' sticks?

Any intel from dovetail folks or even just somebody familiar with how a jig could be oriented to do this job.

I will be settting this up for a pretty big production run, not a one-time event.

Probably not going the CNC route but we'll see. Thank you

[Morey St. Denis]

This problem has occurred to me before in the instance of producing compound angle box jointery for custom casket corners. It occurs that a jig and tool set-up might be fashioned from a used chop saw or compound miter saw. Choose an appropriate carbide toothed box jointing blade where your lengthy workpiece can be fixtured to orient flat or tipped slightly downward from the bed or a platform somewhat above, but largely parallel to saw blade arc while lever-clamped projecting at right angles to the normal fence and guide. Then carefully increment along the desired box jointed width with assistance from a kerf-matching interlocking gauge block strategically located. What say you to that idea; workable?..

[roy labeau]

Well i guess I would be in agreement that yes, it is far better to move the tool, as opposed to the large work piece. Thank you for replying- hope someone has used a dovetail jig in a position other than upright on a bench. Maybe I will be the first. "hold my beer- watch this"

[Bill Adamsen]

Roy ... I don't have a tried and tested method, but it occurs to me that with little modification (the same sort of indexing peg used on a tablesaw box joint jig) a horizontal router might work very effectively. I have a pneumatic Hoffmann Dovetailing machine that were one to replace the dovetail bit with a straight bit and add the indexing I could see it providing a solution. Might also be something that could be done with Jon TenEyck's horizontal router.

[Floyd Mah]

Do you have a second floor deck? How about a window that you can clamp a fixture and a router jig to? Dig a well and finish the job before the water comes in. Any way that you can use your router at a convenient height and have the rest of the work dangle below would work. This is a lot like the problem of the teacher giving his students the problem of measuring the height of the building (http://www.snopes.com/college/exam/barometer.asp) using a barometer.

[Larry Edgerton]

Buy a Matchmaker.

[Dave Zellers]

Seems like Matthias Wandel's pantorouter would work very well for that.

http://woodgears.ca/pantorouter/index.html

Videos- https://youtu.be/PDPrFJazD3Q?list=SP7A1D94FF4FF10854

[Pat Barry]

Why a box joint? On a pair of boards this wide a box joint will be more trouble than its worth. Do you have a router? If so, get a drawer lock bit and you will have a better fitting joint without working on a ladder. Seriously, don't work on a ladder

[Larry Copas]

I will be settting this up for a pretty big production run, not a one-time event.


With that premise you need a machine that will cut the joints in an efficient manner. Folks that make bee super's have such a machine. Here is a youtube example but do your research and you will find others. A good search term is "Beehive box-finger joint cutter".

https://youtu.be/PSLbZ22So1A

The machine is actually quite simple. A long arbor that mounts multiply saw blades. I'm not aware of any machines that are manufactured for the purpose, but any competent machinist can build the machine. As they are so simple I wouldn't think it would be too costly.

[roy labeau]

Ok thank you, it seems like a Leigh dovetail jig is the simplest way to go. I will make a station for it that will allow for 72" to hang below it. I may also make DT's as well as box joints because I need the aesthetics (box joint looked awesome on prototype).

Nobody has turned their jig sideways yet? I don't see why it wouldn't work.

[Doug Hepler]

Roy,

Yes, of course, you put the work flat on a workbench, but you don't turn the jig on its side. You remove the BJ template from the jig. I have a PC jig and here's how I do it. Lay out the joint on the end of the workpiece as if you were going to cut the joint by hand. (The whole width, both pieces of the joint. Shocking, I know, for a power tool person.<grin>)

If you like, you can make a layout and test template using the BJ jig normally.

Obviously a BJ this long has to be perfect, so try it on scrap first.

Remove the BJ template from the jig and align it with the layout lines on the workpiece (laying on its side on your bench). Clamp it or screw it in place. At this point you can attach positioning blocks to the template if you want. At least, you will want a positioning block at one end. (You may have to fiddle with how you fix the template to the workpiece to get clearance for the router base.) Cut the fingers.

Make a spacer block that perfectly fits one of the sockets you just cut. Make it so that you can put it between the positioning block and the workpiece. Cut the mating piece.
Alternatively, you can make a spacer that fits into a socket and spaces the template over the width of a finger plus clearance for the wall of your guide bushing. For my router, the guide bushing is 1/8" thick so I need to move the template the width of a finger plus 1/8".

Rather than getting the spacer block exactly right I prefer to lay out the joint and adjust the template with a spacer. I just use a piece of wood that is 1/8" thick and use it to measure from the layout line to the template. Have a look at this: www.portercable.com/jigs/dovetail/SupplementalManual.pdf (http://www.portercable.com/jigs/dovetail/SupplementalManual.pdf)

Doug

[roy labeau]

I have now found a commercially available jig that can make half blind DT's in a single pass.

Perhaps I can use the 6 footer on the horizontal and since the other board is only 24", i will put that one in the traditional (hanging) position.

Route them both at once, and hope to be satisfied with a half blind...

[Edwin Santos]

I think you can do this quite easily using the Keller Jig which will allow you to do box joints or through dovetails. I would do it using a router table, with the workpiece clamped to the jig. If your ceiling height is an issue,you could move your router table outside. Should be quite comfortable and applicable for a production situation. My router table is about 30" high so your workpiece size would easily clear my 11' ceiling. I suppose you could fashion a router table top quickly and clamp it to a low sawhorse if you like. Of course if the machine gets too low it will be uncomfortable to perform the operation.

In theory I think you could perform the operation horizontally with a the router handheld sideways like you mentioned, where the workpiece/jig is stationary but I've never done it, and gravity would not be totally on your side, but like I say, it should be doable. If I did this I would orient the jig so I am cutting downwards not upwards and just take care to be sure the router is pushed up against the jig. I think you would be able to gang rout 2 or 3 workpieces at a time which will speed things along.

If you research this idea further, give David Keller a call and he will surely offer you some advice and guidance.

[roy labeau]

Thanks for the good idea Doug, I like it and was typing my reply not to you directly- we were both typing at the same time!

Edwin yes just also looked at the large Keller. Just seems kind of sketchy with a 24"x72" piece up on end. I surely would not want to do it over the TS. Thanks for your support on the laying it horizontal option.

This horse ain't dead yet.

[Edwin Santos]

Thanks for the good idea Doug, I like it and was typing my reply not to you directly- we were both typing at the same time!

Edwin yes just also looked at the large Keller. Just seems kind of sketchy with a 24"x72" piece up on end. I surely would not want to do it over the TS. Thanks for your support on the laying it horizontal option.

This horse ain't dead yet.

In case this helps here's a photo of a largish pinboard workpiece on end using the Keller jig. I recall the drawer being 38" and 13 or 14" high. Granted yours would be nearly double in length, but if clamped down as I show, I see no reason why you couldn't do it. I prefer using this jig on the router table because of better dust capture.

This is not to talk you out of the horizontal application where you are using the router sideways because I think that would work too although I would do a practice run or two on some scrap to get the technique down.

I've been thinking about what I suggested about orienting the cut on the downward side (jig fingers up). The only problem with it is the chips will be thrown back at your face due to the bit rotation. This is why when they demonstrate the Keller, the fingers are facing away from the operator and he is pulling the router toward the fingers and throwing the chips forward.

The Keller jig is the only router DT/BJ jig I have ever used so I don't fully understand what Doug suggested but it might be the winning idea.
355909

[Ray Newman]

Edwin Santos: I have the older Keller jigs (1600 and 2400) and they work as advertised.

Hopefully I will build a new tool cabinet this year -- about 16" deep, 42" high, 27" wide, dovetailing the carcass. Thought about utilizing the Keller in the router table, but have a question. To reduced friction as the jig moves across the router table, did you apply any UHMW "tape" to the jig -- cutting out around the jig fingers?? Or, maybe a good application of Johnson's paste wax to the jig and router table??

For those Not-In-The-Know:

UHMW -- https://www.woodcraft.com/products/slick-strips-3-4-width-1-32-thick
Keller -- http://www.kellerdovetail.com/
Keller video -- https://www.youtube.com/watch?v=6GEYM7HNcPw

[Edwin Santos]

Thought about utilizing the Keller in the router table, but have a question. To reduced friction as the jig moves across the router table, did you apply any UHMW "tape" to the jig -- cutting out around the jig fingers?? Or, maybe a good application of Johnson's paste wax to the jig and router table??



Ray,
Yes, I used a few strategically placed strips of thin UHMW tape on the jig. It was less about friction and more because I didn't want to risk scratching up the anodized router table insert plate. It's important to make sure the pan head screws on the pin jig are tightened down really well or they may be ever so slightly proud of the jig surface and cause scratching. Paste wax is a good idea also. Good question.

I ended up buying the 2401 to go with the 1600 because there are times I like the wider pin spacing from an aesthetic viewpoint. These jigs have worked very reliably for me. Ed

[John C Bush]

Good article in Fine WWing Dec 2014, issue 243 on Greene and Greene blanket chest with box joints on larger stock. Instructions with pics for a custom jig look fairly simple and would work well for larger production runs. I can send copy if interested.

[Ray Newman]

Ed Santos: thanks!

[roy labeau]

Good article in Fine WWing Dec 2014, issue 243 on Greene and Greene blanket chest with box joints on larger stock. Instructions with pics for a custom jig look fairly simple and would work well for larger production runs. I can send copy if interested.

Yes john can you send link, an article that addresses "box joints on large stock' would be helpful.

thanks.