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View Full Version : How would you make this?



Mike Johnson - Chicago
12-10-2004, 4:57 PM
I've got some ideas, but don't want to lead the jury :)

The intent is for the dimension between the shoulders to be the only critical dimension...besides the dovetails fit of course.

The "problem" is the length/depth of the pins...and the need for a clean precise shoulder.

Take a look and tell me what you think!

Thanks in advance,
M.J.

P.S. I am going to make a total of 36 of these (72 'ends'). So keep that in mind :)

Chris Padilla
12-10-2004, 5:10 PM
Router table with appropriate dovetail bit. You'll need to do some careful paring and sawing to get clean flat shoulders at the base.

Doh, just caught your P.S. Well, it'll be fast and accurate for most of the cutting but the handwork at the end shouldn't be too bad with a good sharp saw and good sharp chisels.

Walt Pater
12-10-2004, 5:59 PM
Bandsaw w/ fence & some positve stops.

Mike Johnson - Chicago
12-11-2004, 1:32 AM
Both of these solutions require handwork to "clean up".

And that would be fine, if I didn't have a bunch fo them to do...

Any other ideas?

Thanks for the input so far,
M.J.

Dean Baumgartner
12-11-2004, 2:05 AM
Table saw joint. Look for a post by Bob Smalsser for something similar within the past week or so.

with a jig to set the angles both ways it should go pretty quick and a flat top tooth on the blade the shoulders should come out ok too.

Dean

Mark Singer
12-11-2004, 2:18 AM
I would not try to saw that by hand....it is difficult to keep the saw straight and in plane...bandsaw is what I would do or change to a simple tenon.

Dave Richards
12-11-2004, 7:31 AM
If I read the first part of your post correctly, the 15" dimension is the critical one. I guess my first inclination would be to create the 1/4" shoulder on each end first. I would do that on the tablesaw with a dado set. I would make the shoulder on one end and then use a piece of 3/16' thick something as a guide to establish the 15" to the other shoulder. Like this:
http://img.photobucket.com/albums/v506/weekender410/dovetailthing.jpg

After that I would cut the dovetails to the shoulder. Tablesaw would work for this with the miter gauge turned to the appropriate angle and a high fence added to it. If you could get the height from it, I'd use a dado set to hog out the stock. Most would be cut out on the first pass.

A bandsaw would be safer but would require a bit of hand work.

A router would also be workable but you still have some hand work unless you could tolerate curved ends at the bottom of the spaces between the pins.

Why don't you show us what you end up doing?

Dave

Mike Johnson - Chicago
12-11-2004, 3:08 PM
Good stuff guys!

The thing that is particularly intersting to me is that prior to starting the post, I was "arguing with myself" about table saw or band saw. And pretty much that's the way the "camps" are split in the responses.

I'm begining to think that it will be a combination of the 2.

As Dave notes in his post, the shoulders are important and I will probably do those first, on the table saw.

I should note that although Dave's renderings are fantastic (I hope your starting with a lot of that stuff already in a model library), I'd be nervous about setting up the second shoulder that way. 2 reasons:

1) The 3/16" guide fence traps the piece between the blade and the miter gage. It seems like it would be fairly easy for the piece to 'catch an edge' on the guide fence and cause either kick back or just a mested up shoulder.

2) Maybe the guide fence was being used to deal with the following...I will have to make sure the second shoulder is parallel. But it seems that when flipping the piece around it now references off a different edge, doubling the parallel error. And could cause the shoulders to be shaped slightly like \ /

(Pretty week image made even worse by following Dave's :)
Granted this may be minor, or non existent if your part was properly prepared with parallel sides...but I've found that I make less mistakes if I take that variable out of my setups.

In the past I have created a small cross cut jig with the fence dadoed into the middle of it, creating a surface infront and behind the fence. The only important step is making sure the runner is attached 90deg to the top fence. I'll place the part to be cut on the jig just like you normally would, cut the first shoulder. Then rotate the piece around to the back of the fence, keeping the same face touching the fence, and cut the second shoulder.

After the shoulders, I'm now leaning towards using the bandsaw with an angled table with a multi-position fence to make each cut.

Yet since I'd really like to avoid the handwork (paring the rest of the shoulder with a chisel), I will probably try out a veritcal tenoning jig type cut to see if it would actually eliminate the hand work...it will be interesting to see if it results in a "clean" shoulder.

There I go again starting my internal table saw vs. band saw argument again!

Sadly, I'm probably not going to get to this until after the holidays. I've got a few X-mas projects to complete AND a Reznor heater to plumb!

Thanks for the feedback all and I'll circle back with the reuslts as they occur.

Regards,
M.J.

Jamie Buxton
12-11-2004, 4:24 PM
How 'bout something akin to loose tenons? Make a rectangular piece 15" long. The ends are the eventual shoulders. Make dovetail-shaped "loose tenons". Use the technique of your choice to connect them to the ends of the 15" piece.

Or here's another outside-the-box approach. Make two dovetail-shaped pieces which are 19 1/2" long. Make three fill pieces which are 15" long. Glue all five together to form the part you've drawn. You'd probably need a gluing jig to ensure that the shoulders are all in a line. The nice thing about this approach is that all the machining is straight-line stuff. You can do it on a table saw, and even clean up all the faces with a jointer.

There's no hand cleanup in either approach.

Dave Richards
12-11-2004, 4:33 PM
Mike, for what it's worth, kick back wouldn't be an issue since you aren't cutting through the piece. Since this is a cross cutting action, you would be using the miter gauge behind the piece.

I would suggest that if you can't get the two opposite sides parallel, you will have further problems cutting the rest of the piece.

Good luck. What's it for anyway?

Mike Johnson - Chicago
12-11-2004, 5:46 PM
Interesting approach Jamie....in particular the laminate. The challenge would be avoiding resurfacing the finsihed assembly because of minor alignment drift, made more challenging by the angles of the pieces...but definately a cool idea.

Dave, your probably right on both accounts. As far as 'what's it for?', take a look over on the design forum at my post regarding the project.

http://www.sawmillcreek.org/showthread.php?t=14479

On a side note, having only just heard about SketchUp, I'm curious if the company has a public depository for "standard" items that folks can use/offer to the public. For instance your table saw and miter gage....I'd think they'd come in handy on a regular basis!

Regards,
M.J.

Dave Richards
12-11-2004, 7:58 PM
Mike,

I forgot to answer your question about SketchUp and components. The tablesaw was indeed a component. It was drawn by Mr Yurko who is member here. I made a couple of minor changes and eliminated most of it for the drawing since those parts don't show.

There are couple of places where people can deposit componetns so that others don't have to draw them over and over. I have the tablesaw stored on my hard drive so I don't have to log on to get it when I want it.

Alan Turner
12-12-2004, 6:29 AM
Mike,
I am late to this party, so your work is probably done, but here are a couple of thoughts. Cut the shoulders on a sled, with the rebate against a stop. Establish the bottom of the DT with a HCM, leaving only minimal cleanup by hand. Cut the cheeks on a BS using the techinique shown in one of the 2 David Charlesworth Furn. Techiniques. I made one of these jigs, and use it only for very large DT's, but it is quite accurate, and the cheeks are clean enough. That would leave only the corners to "chop" and with the line established by the HCM cut and the BS, not a lot of work.

I am reading all of the back issues of FWW (slowly), and just reread the article on a Barnsley dining room table. You might take a look at FWW No. 48. Neat stretcher design.
Alan
Alan

Mike Johnson - Chicago
12-12-2004, 2:36 PM
Alan,

I'm far from through...probably won't start until January.

Thanks for the ideas. I'm 90% sure that I am going to start with a crosscut sled on the table saw to set the shoulders. But thus far I havn't seen a method that looks clearly better than the others, for the rest of it. So, I'm going to try both the band saw and the table saw...and maybe even a router...to see which way will be most efficient (for me) at making 72 of them.

The router is the only the seems like it could do it all in one cut. But the 2-3/4" long cutter seems suspect/risky...if you could even find one.

Anywhose, on the FWW, I'm dissapointed to see my collection starts in the 30's, but for some reason I don't have 48! I actually didn't start buying them until ~issue 128, but I picked up from 36-128 from a garage sale.

Regards,
M.J.