Bandsawing with templates

[Jim Murphy]

As the astute reader will remember, I am about to embark upon an Adirondack building extravaganza. In anticipation thereof, I have carefully manufactured hardboard patterns for the curvy parts. As serendipity has a way of dropping in at opportune moments, the new issue of Popular Woodworking has a bandsaw article with a paragraph on using a template and guide for duplicating using a pattern.


PW Article here

Google produced this result from a Woodcraft article.

Okay, no inside cuts allowed, so says Woodcraft. Ideally suited for rockers. Okay, does that mean you can cut one side of the rocker but not the other? I can't wrap my mind around this.

FWIW, I intend to use the router and a nice new Freud industrial pattern bit to clean up the the rough edges.

Question: has any NCWWer attempted this? If yes, please share your thoughts on whether this is amenable to adirondack shapes. Thanks.

 

[woodworker2000]

Rockler sells a duplicating pin for the bandsaw (see: http://www.rockler.com/product.cfm?page=18055). I don't own one nor have I ever used one so I'm not sure how well it works.

 

[DaveO]

I don't see much value in going through that effort if you plan to flush trim to the pattern later. What I have always done is affix my pattern to the blank and use it as a visual guide to keep me within a 1/8" of it while bandsawing the blank out, then you are ready to flush trim it with a router.
I don't see why you couldn't use that method for all the components of an Adirondack chair, there really shouldn't be any tight inside curves that would be problematic.
Dave

 

[Travis Porter]

I 110 percent agree with what DaveO said. As for inside, they are talking about inside like you would have to use a scroll saw for, not concave or convex.

 

[cpowell]

I haven't used it before (I saw close to the line and use a router to clean up) but I am keen on trying it out someday. I would think that monotonous gradual curve cutting would be a perfect application. I don't know if it would be worthwhile for a single chair but if you're making a bunch I think it might be a time saver.

The toughest part is notching the guide, right? Of course the guide end curve radius needs to be smaller than your smallest curve radius.

BTW the Robinson Cadet BS in the first article looks like an awesome beast, and he's got it set up pretty sweet with the lignum vitae blocks.

If you give it a go let us know how it works for you.


Chuck

 

[McRabbet]

Jim,

Steve DeWeese (SteveD, an older member who has not been on the site much lately, but who is an accomplished woodworker) used 1/4" plexiglass templates that had foam wweather stripping around one side near the edges and a vacuum connection on the top side. After rough cutting the parts for his Adirondack chairs on his bandsaw, he used these quick adhering (and no mar) templates with a pattern bit on his router table to flush trim them to exact size. He said it was fast and easy to change to the next board or template. Unfortunately, he doesn't have any pictures of the templates in his Gallery, but he showed them to me in his shop. Oh yes, one detail I left out -- he made 75 chairs out of cypress at once for his company President to give as employee gifts (on commission, of course). If you want I can give him a call for more details.

 

[Wildwood]

The Band Saw Handbook has illistrations for using a single point fence and templates for making chairs which makes it look simple to do.

I have an old edition, not sure if included in new one.

 

[CarvedTones]

A counterpoint...

I made some Adirondack furniture that is still on my front porch. I got full sized plans and traced one of each different shape on stock, cut those out freehand and traced them onto other stock that I cut out freehand. I then stacked stock that was supposed to be identical and looked for any major deviations, with the intent of planing down corners that stuck out or maybe replacing anything that was too far out. Nothing was. Are they perfect? No, of course not. They are very close and that is actually (IMO) more authentic to this style than the cookie cutter factory CNC look. One disclaimer though - I am lousy at most furniture projects where things have to be dead flat and meet up perfectly, but give me a sharp pencil and a skinny blade that is appropriate for the stock and I can follow a line pretty well.

 

[Jim Murphy]

Thanks for the replies so far.

Christopher, the duplicating pin looks like it would do very much the same thing.

DaveO, when eyes get older, the lines are harder to see. Other pitfalls appear with age, some more egregious than bad eyes, but for six chairs, this seemed to show promise.

Travis... I mean, that's a "duh" moment if in fact the dude meant that I couldn't cut inside curves with the bandsaw. It just never occurred to me that the writer thought anybody was so stupid as to think that a bandsaw that couldn't cut inside curves without a follower guide could somehow do it with a guide, well, it just didn't dawn upon me that way.

Chuck, I'm gonna give it a go.

Rob, it's that tortuous rough sawing that I'm trying to improve on.

Wildwood, my BandSaw Book has gone into hiding, and I haven't yet had the LOML issue a search warrant. I'm having trouble visualizing how the single point fence thing would work. My SPF (single point fence, not SprucePineFir) attaches to the regular fence and seems like it would block adequate movement of the raw stock to follow the curves.

Andy, the idea of having the bandsaw follow the pattern was not about perfection, or exact duplication, but an idea to make it easier to saw out the stock for six chairs. Yeah, I can follow a line with the saw and make pretty decent smooth curves, but it 'shore' is a lot easier and lots faster to saw following a guide.

I'm going to experiment with this technique. Currently, I think that I might try using small nylon washers as rollers. I don't know if I can position them such that, allowing for adequate blade clearance (1/2" blade), the contact points are close enough to track correctly. If I can't work out the roller concept, next idea is to still use the washers, but not axle mounted as rollers-- merely as slick fixed guides.

I'll set up a jerry-rigged follower arm with notch and washers and try cutting out something simple in trash stock. Of course, I'll keep you'se guys apprised of my failures.

 

[gator]

Wildwood, my BandSaw Book has gone into hiding, and I haven't yet had the LOML issue a search warrant. I'm having trouble visualizing how the single point fence thing would work. My SPF (single point fence, not SprucePineFir) attaches to the regular fence and seems like it would block adequate movement of the raw stock to follow the curves.

I tried to find a picture but failed. A true single-point fence is 1X material (or 3/4 or something close) turned on edge and the end rounded off. Notch the other end and nail/screw/glue a cross piece on. Cross piece is used to clamp the board (on edge) to the table. All you have near the blade is the perpendicular rounded 1X, lots of room to move the workpiece around the edge to cut a fairly deep concave.

George

 

[gator]

Found a picture of one similar to what I was talking about

http://www.woodcentral.com/shots/shot363.shtml

Looking as the back side, if you leave off the front 'V' and just use the vertical block of wood on the base, its about what I meant.

George

 

[gator]

Oops, found another

http://books.google.com/books?id=gC...wdULt8s&sig=nOOGCntnSdlXHb4wh1kDTeN_LV8&hl=en

George

 

[Jim Murphy]

Of course, I'll keep you'se guys apprised of my failures.

Well, well, well. Check this out:

That's a piece of HDPE from Agri-Supply with a serious rabbet whacked out of the lower half bottom. Some 50 grit Klingspor bargain bin abrasive rounded the points.

It's attached to a scrap of Jeff... gum with 3 countersunk #8 X 5/8 FH screws. The countersink was a DeWalt 2538 chucked up into a Harbor Freight $15/18volt reversible drill. I used a new Kobalt #2 Phillips screwdriver obtained from Lowes to attach the HDPE to the gum (Okay, I'm joking here, trying to sound like one of those magazine articles). It's clamped tightly to the table top, and there's a wobble bracket clamped to prevent rearward movement. On the next version I think I'll make a triangular carrier to be able to clamp at each end of the table and eliminate the risk of twist.

Here's a closeup:

And here's the result:

The final result (while still DS taped to the pattern) was ready to hit the router table for final cleanup.

The next interation will have almost zero blade clearance. I didn't need nearly that much opening, and had to be careful when starting the cut to engage the rear contact point. Once both points were in contact it was Wheee! let's cut. The guide did the work of guiding, I just fed the material. Real smooth and fast.

Now, it was necessary to very crudely rough out the blank (actually I just ripped and crosscut it to a big rectangle on the TS), as the gum arm can interfere with the cut on the "inside" cut. Next version I'll provide more clearance between the blade and the gum arm.

My opinion is that this is a very worthwhile jig/rig for making multiple copies of the same thing. It took about ten minutes to throw the prototype together, ten minutes to muck with setup, and then it's ready to go.

 

[woodArtz]

Now that is cool! I just got another commission for more Adirondacks, so I might borrow your design. Thanks for sharing :eusa_clap.

 

[garymuto]

That's a great idea. I like the way you thought it through, put it together and are already thinking about the next generation jig.