Cnc routers for riser shaping

[BrushWolf]

Was wondering what Cnc setups would work and if anyone had experience with one? Mainly to rough out risers

[Crooked Stic]

They work. Widows Blacktail and Rose Oak. Programming prolly the big thing.

[BrushWolf]

It save a lot of wood rasping. Even looked at copy carving machines

[Kirkll]

 I believe the trick is in programing the cutters to climb cut certain areas where cross grain tear out occurs.  I have no experience doing it with a CNC, but have enough mill work experience using various cutters to know there is always issues with tear out to deal with. I'd advise practicing on inexpensive material before blowing out expensive hardwood.  .02 cents worth...

[dbeaver]

There are plenty of tools between rasps and CNC that work well, just sayin. 

[derekdiruz]

I use a CNC. I'm a 1 man shop, and the real benefit with a CNC is allowing me to do something else.
For instance, it's much quicker to just hold a limb edge against a belt sander to profile it. But the CNC takes 1 minute to set up, and while I'm able to prep another glue up, or do tips, or anything else, it's profiling the limbs.

Bed size, spindle/router size, bit size, stepper motor sizes, all play into the efficacy of the CNC.

You can get a tiny one that uses palm routers and do risers just fine. The bigger hold up is the design. Most of those will come with base level software and not have the ability to design in 3D. With that, you'll have a riser that's consistently cut with say, pad angles, but you will have 80% of the work left to do by hand with shaping.

If you plan to get into CNC, you'll likely want to go the route of 3HP spindles or bigger, so you can use 1/2" bits not just 1/4" bits. The bigger CNC will include higher end software (or you could spend a few thousand to get this software otherwise) to allow you to get deeper into design. The feed rates of better CNC may be in the 400 IPM range versus the 150 IPM max range, meaning you have much less time running the machine.

There's a massive learning curve to CNC. It's not just "buy one and go" unfortunately.
I've used mine for roughly 200 bows over the past 3 years, and I feel like I'm only about 60% of the usage I could be with it.

Good luck, if you have any specific questions I'd be happy to help.

[Kirkll]

I use a CNC. I'm a 1 man shop, and the real benefit with a CNC is allowing me to do something else.
For instance, it's much quicker to just hold a limb edge against a belt sander to profile it. But the CNC takes 1 minute to set up, and while I'm able to prep another glue up, or do tips, or anything else, it's profiling the limbs.

Bed size, spindle/router size, bit size, stepper motor sizes, all play into the efficacy of the CNC.

So how many risers have you had issues with grain tear out to deal

You can get a tiny one that uses palm routers and do risers just fine. The bigger hold up is the design. Most of those will come with base level software and not have the ability to design in 3D. With that, you'll have a riser that's consistently cut with say, pad angles, but you will have 80% of the work left to do by hand with shaping.

If you plan to get into CNC, you'll likely want to go the route of 3HP spindles or bigger, so you can use 1/2" bits not just 1/4" bits. The bigger CNC will include higher end software (or you could spend a few thousand to get this software otherwise) to allow you to get deeper into design. The feed rates of better CNC may be in the 400 IPM range versus the 150 IPM max range, meaning you have much less time running the machine.

There's a massive learning curve to CNC. It's not just "buy one and go" unfortunately.
I've used mine for roughly 200 bows over the past 3 years, and I feel like I'm only about 60% of the usage I could be with it.

Good luck, if you have any specific questions I'd be happy to help.

So how many of those 200 bows have you had issues with grain tear out? Does your programming take that into consideration?

I'm also curious about how you deal with limb alignment on a 3 pc TD if you are profiling limbs prior to mounting them?   

I use a vertical milling machine for drilling my location pins and limb bolts on both the limbs and risers and even then, I typically have limb alignment adjustments before profiling.

How do you deal with that?   Kirk

[BrushWolf]

I use a CNC. I'm a 1 man shop, and the real benefit with a CNC is allowing me to do something else.
For instance, it's much quicker to just hold a limb edge against a belt sander to profile it. But the CNC takes 1 minute to set up, and while I'm able to prep another glue up, or do tips, or anything else, it's profiling the limbs.

Bed size, spindle/router size, bit size, stepper motor sizes, all play into the efficacy of the CNC.

You can get a tiny one that uses palm routers and do risers just fine. The bigger hold up is the design. Most of those will come with base level software and not have the ability to design in 3D. With that, you'll have a riser that's consistently cut with say, pad angles, but you will have 80% of the work left to do by hand with shaping.

If you plan to get into CNC, you'll likely want to go the route of 3HP spindles or bigger, so you can use 1/2" bits not just 1/4" bits. The bigger CNC will include higher end software (or you could spend a few thousand to get this software otherwise) to allow you to get deeper into design. The feed rates of better CNC may be in the 400 IPM range versus the 150 IPM max range, meaning you have much less time running the machine.

There's a massive learning curve to CNC. It's not just "buy one and go" unfortunately.
I've used mine for roughly 200 bows over the past 3 years, and I feel like I'm only about 60% of the usage I could be with it.

Good luck, if you have any specific questions I'd be happy to help.

What Cnc machine would you recommend looking at for purchasing?

[Kirkll]

I'm the wrong guy to ask about CNC set ups. All my millwork experience is limited to high speed shapers, pin routers, bench mount table routers, and trim routers. I built boats and furniture for a number of years before getting the bowyer bug. I worked at Christensen Motor yacht for a couple years in a beautiful shop that had everything except CNC set ups... now it's pretty much all done that way.... I built a lot of spiral stair cases over the years that were fun too....The true craftsmen are a dying breed.  Kirk