template routing for small pieces

[linear]

Hi gang,

I am working on a bandsaw box of sorts, but it offers me the opportunity to template route some of the pieces--it's not laminated, the pieces will stack together into a fial assembly. I guess it's only a bandsaw box in the sense that used a BS to cut some of the curves.

The pieces are small, no longer than 4", and are all curves. I've made a template in MDF, and I've rough cut my blanks out of the stock (bloodwood, very hard) on the bandsaw so that I've got very little to waste away with the router.

I tried this with my router handheld last night, and it went pretty badly. I was using a Whiteside spiral flush trim bit, and I had the template on the bottom. I didn't really have adequate support for the router on such a small workpiece. It bit some good chunks out and scared me into stopping and reconsidering.

With some time to think it over, it seems like using the table would be a better plan, since I'd be free of the need to maintain a perpendicular relationship between bit and work--so that problem is solved. But I don't like the idea of getting my hands in there.

So I figured the way to go is build a sort of sled that I can toggle clamp the work and template on. I want my hands more than a foot away from that bit (and more so after seeing the bloodwood get chomped up badly--I prefer no actual blood in my bloodwood boxes).

I'm a little hazy on the safety of this approach (specifically the lack of a fence to register against). I know about a pivot pin, but I'm not certain if that's a necessity with this technique. It seems like it would add some safety to the setup to just clamp a piece of scrap to the table top, put the sled with work on it in contact with that point first, then pivot into the spinning bit. It's the moment between the work contacting the bit and the bearing contacting the template that seems to hold the potential for unpleasant results, I think this would improve my results, but can I do better?

Some guy named Rogowski () is demoing this technique more or less here:
http://www.taunton.com/finewoodworki....aspx?id=26755
He doesn't seem to have a pivot point, but it's hard to tell. He does have his jig set so you can contact the bearing to the template without removing any stock, and I can't pull that off since I have no straight edge on my template, which are almost entirely convex curves.

I've also read some things that lead me to believe a larger cutter diameter would help. I have the ability to use a 3/4 template bit (straight flutes) or a 1/2" flush trim bit (ditto) instead. I figured spiral flutes would be best to get a clean edge on the bloodwood. In any case I'll run some scrap before I commit the good stuff, but I'm curious what's your bit of choice for template work?

Thanks in advance,
Rob

[jackellis]

The Rogowski illiustration does, in fact, shows the best way to do this. You don't use an external contact or pivot point. Instead, you use a flush trim or pattern bit. The guide bearing rides against the template, which is set on the cut line so that the bit removes any excess stock. A jig with handles that attaches to the pattern with double-sided table keeps your hands away from the stock.

[LCHIEN]

Table is highly recommended for pattern routing small items.

If the item is really small and you hands are dangerously close to the bit,
consider making a extenison to the pattern and routing half of it at a time, moving the extension to the other side for the second half.

I feel that a larger dia. bit is easier to control - the angle of the bit hitting the wood aren't so large, I think.

[crokett]

Linear, I use a flush trim bit for template routing with a table router. I have built a couple rocking horses this way. I do what loring suggested which is build an extension, rout half, switch then rout the other half. I do use a pivot point to start the cutting - it seems a bit safer to me than feeding the work directly into a spinning bit.

[linear]

I can see a couple new solutions based on this. If I select the pattern bit, I can align things so I put the sled supporting work+pattern on contact with the bearing before work contacts the cutter, alleviating my concern above. But I already cut my patterns, so I'll probably do this crokett-style, and consider alternative pattern techniques next time I make one.

Thanks gents.

[JR]

You might also consider using a screw clamp to hold the assembly while your running it through the router. That'd keep your hands away from the bit.

JR

[LarryG]

A couple other possibilities:

1. Hold the template/workpiece down with a jointer push block or similar that has a non-slip pad on the bottom.

2. Before attaching the template to the workpiece, screw it onto a short piece of dowel that will serve as a handle. Don't make the dowel too long or you'll have a hard time holding it vertical, which depending on the type of bit could either be harmless or could ruin the cut.