Comment by robomartin | Hacker News Reader

Comment by robomartin | Hacker News Reader

Interesting project. I am sure it was a lot of work (and fun as well).

I was introduced to the general concept when the Shaper Origin came out a while back. Here's my problem with the idea:

What's the use case?

Any xyz gantry router will run circles around this approach, by far. They will be much faster, more accurate and, more importantly, hands off. There's a lot to say for clamping the material and mashing the "go" button. The pattern shown in the video on the YT channel literally takes three seconds to cut on a gantry router. And you can swap material and push go again, very quickly (or cut as many as possible out of one piece of material.

For around $1K you can have a much more capable machine. Unless the use case is cutting/engraving on items that cannot be cut on a traditional router, I am not sure what these would be used for. Then the question becomes: How many of those projects do DIY hobbyists have?

The other question is one of accuracy and repeatability. Having done loads of CNC metal machining, CNC and manual wood routing, I can tell you that nothing beats a rigid xyz machine.

So, if someone has just one or a few odd parts that cannot be cut on an xyz router, well, maybe that's a use case. Other than that, why would anyone guild one of these rather than a gantry?

The workflow on the shaper origin is extremely nice, --- apply tape, swing it around to capture the environment, load svg and position. If you need a regular spacing grid, you just press a few buttons and ram the tool into three non-colinear points on the edge of your object.

You can cut objects in place, including irregularly shaped stuff you'd need to disassemble to put on your gantry. That comes up frequently for engraving but it's not exclusive to it.

The whole device is basically the size of a sewing machine. Yet it can cut parts that won't fit on an gantry you're able to fit in your garage.

It's quite tedious for repeated work. So I think it's really more in the class of manual power tools than in the same class as a CNC setup.

As far as accuracy goes, the tracking tape eliminates some source of errors. Say your clamping is not 100% and the part shifts slightly while being worked-- tape the part moves with it and all is still happy. Of course, it introduces some of its own problems too.

So in summary:

1. Very small device, yet can work with arbitrarily large pieces. 2. Good workflow means very fast setup suitable for one offs. 3. Works in situ, especially useful for engraving things in place.

I imagine that if it weren't a bit pricey that many people who do CNC woodworking would also have a shaper origin like device-- much like you probably have a skillsaw in spite of owning a CNC router.

Plus the simplicity of setup and the size makes it attractive to anyone who only wants a tiny amount of CNC for precision engraving, hole positioning, or cutting an inset for a hinge... and would never own a CNC gantry.

> engraving things in place.

That's just-about the only real use case I can see.

And then, again, is the question: How much engraving in place does anyone really have to do?

What are you engraving? Doors? Signs? Trophies? Well, if it is a one-off occasional thing...is the cost justified? If it is done as a business, chances are you are not going on-site to someone's home to engrave stuff. If it a rare once-in a couple of years thing, there are services that will do that for you for very little money...etc.

Forget CNC, I am comparing this to a $50 router and some jigs, off-the-shelf and self made. Even as a robotics guy, I just don't see it. And I have a shop full of robots and CNC machines.

To me this falls under the category of "just because you can, it doesn't mean you should".

Hand router jigs:

https://www.rockler.com/power-tools/routers/router-jigs

Hand router sign-making templates:

https://www.rockler.com/power-tools/routers/router-accessori...

I'm happy to be wrong...I just don't see it except for corner cases (which could be all you need for a nice business).

FWIW, I use a Shaper and I think there are four areas where it is better than a gantry. If I was just blasting out flat parts, I'd go for a typical gantry setup. But I very rarely do that.

1.) Cuts that are not easy on a gantry. It would be very difficult to do a tenon on a gantry. You could do one side and then flip the piece. Or maybe you could have a special bed with a void for putting stock in that direction. Either way would be difficult to get just right. With the Shaper and their workstation this is a 60 second operation.

2.) Cuts in the real world. If your stock fits into a gantry, great. But if it doesn't then you're going to have to dismantle the thing to get it into your CNC. With the Shaper I've done inlays on-site, in hardwood floors, kitchen counters, on walls, and on a rough surface picnic table.

3.) Sneaking up on tolerances. Again, if you're batching out a ton of stuff you'll get your tolerances once and everything will be set. But when I use a gantry getting the tolerances just right takes a ton of time. On the Shaper you cut a pocket, test fit, bump the tolerance by a thou or two, recut, and re-fit. This is fast on the Shaper.

4.) Storage space. I don't have a ton of space. I have a small CNC (~15" x 15") for small stuff that I want to batch out, but I work out of my garage. I'd love to drop a 4' x 8' CNC in there, but it isn't going to happen. With the Shaper it all goes into a systainer box and sits on a shelf. When I want to do something big I lay some foam down on the driveway to use as a backer, drop the wood, lay out the tape, and go.

It's crazy pricey. But that's more because it's owned by Festool than any inherent reason. If you're the kind of prosumer who goes for Festool-grade tools then it's probably a decent fit.

Size I assume - this should be able to handle massive projects at the same price, while a gantry router would be much more expensive. Or so I would assume, I didn't dig into this to see how large it can go.

it's in the second sentence of the link:

> It automatically adjusts the cutting tool to stay on the programmed design path, enabling a significantly smaller device footprint while still handling large-scale cuts.

I don't know how many people it concerns but the use case is very clear

Not really. I have done tons of manual wood working. I have 8 or 9 manual routers and a couple of CNC machines (real industrial ones, metal and wood). I have done just-about every type of intricate joinery using manual tools and inexpensive jigs. If you have metal CNC it's great because you can really get creative with jigs.

My comment wasn't intended to denigrate the tool or the approach. I am trying to understand the use case at scale.

Why?

Because if you are going to use this type of a tool onece or twice a year for an odd job, you don't need it. A $50 router will do just-about anything if you take the time to make a jig or jigs for the job. Again, if it is an one-in-a-while job, the time taken to build jigs is not important.

If you are making dozens or hundreds of something, forget it. Not the right use case. A CNC router or, again, a set of jigs or fixtures is the ticket.

Oddly shaped material might be a use case, however, I cannot see this working on concave or convex material with any degree of precision. This, once again, depending on the nature of the work, falls under the realm of CNC (possibly 4 or 5 axis) or specialized jigs.

Having done so much work, I just can't see dropping that kind of money for something that isn't likely to give me any real advantages. It will get used a few times due to the cool factor and then just sit on a shelf while I get real work done using manual or gantry CNC tools.

I've probably built hundreds of custom workstations using 100% manual tools, jigs and fixtures. It works, you can get amazing precision and repeatability and there's no limit to what you can make. Best of all, if you need five people working on a project, making extra jibs and fixtures is easy and cheap.

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