[harryn]

Stand alone is nice, but perhaps another path is to upgrade your larger machine to have the precision and rotary nature you desire. Two birds with one stone.

[CarveOne]

Stand alone is nice, but perhaps another path is to upgrade your larger machine to have the precision and rotary nature you desire. Two birds with one stone.

I considered that. The stand alone machine will give me a larger diameter capacity than the 6" table clearance my big machine has. It can be built stiffer also. So that the Z axis isn't so tall, I may consider mounting the router horizontally so that Z zero is much lower for an 8" or larger object, like carving the edges of a bowl, or a round or hex shaped box. There are no sketches or CAD drawing work going on yet. Will have to wait until after I get back from the Aspire Camp at McGrew's.

[CarveOne]

All of that was made with just 12 vector lines total.

Inside the ellipse is domed a little (Create Shape from Vectors tool) and the knot border, ellipse border and text are extruded shapes. The text bends with the shape of the ellipse. I don’t plan to cut it, but you never know.

I could scale it to fit the Paradise box I made to take to the Aspire Camp and swap out the top panel when I get back. The box would make a good router bit storage box.

[CarveOne]

Here's how the extruded weave Celtic cross is looking after the first coat of poly. Later today it will get a first coat on the back side.

[PaulRowntree]

I don't think it can get any better than this CarveOne ...

[CarveOne]

Thanks Paul.

It is my intent to upload a 20 Mb zip file of this one (contains the .crv3d and dxf files) on my website and link to it here and in the Vectric Forum's Aspire Gallery sometime this weekend. The dxf file isn't any good for Vcarve since I have redrawn it as a single vector knot for the extrude and weave tool. The older version was a shape from Vcarve vectors project.

Even the gcode file is 32.7 Mb - unzipped.

[CarveOne]

It's all finished and waiting to go to the Aspire Workshop at McGrew's Woodworking next week.

[TrickyCNC]

very good work C1

[r00t4rd3d]

Aspire Workshop at McGrew's Woodworking next week.

Wish I could goto something like that.

Did you ever post the cross files on your site? Looks......

[CarveOne]

Thanks Tricky,

I'm really enjoying the latest upgrade to Aspire. It seems like the Woodworking forums has become a ghost town since the new interface was implemented here. Hope it gets squared away soon.

[CarveOne]

Wish I could goto something like that.

Did you ever post the cross files on your site? Looks......

McGrew's is a 2-1/2 hour drive from here and it's all interstate.

Not the latest one for Aspire 4, just an STL model of the original version. I'll post a dxf file for the vectors here if you want that. It will work well with Vcarve Pro or other Vcarve software. Post #2419 has an attached file for Vcarve Pro. This is the link location:

http://www.cnczone.com/forums/attachments/cnc_wood_router_project_log/171661d1353888367-carveones_steel_channel_rebuild-celtic_christian_cross_-_large.zip

My bad... That is the dxf file in the zip file.

[r00t4rd3d]

I was able to figure it out with the stl, thanks.

[CarveOne]

Very good. Which software do you use?

The only difference I see is that I have been doing a pocket for the four inner holes. The only 1/8" cutter I have that has at least 3/4" cutting depth is a RotoZip cutter that has a chisel tip. That gives a small radius corner in the holes.

[Sally600]

I considered that.

[r00t4rd3d]

I converted the STL to DXF with Sketchup Pro then did the rest in Aspire.

I use these .125 Carbide Endmills with a 1/8 to 1/4 Adapter. For the 3D tool paths I use a 1/16 Ball Nose.

[harryn]

Thanks Tricky,

I'm really enjoying the latest upgrade to Aspire. It seems like the Woodworking forums has become a ghost town since the new interface was implemented here. Hope it gets squared away soon.

Yes, I am still figuring things out on it. I normally use IE in a fairly nailed down configuration, but decided to try firefox and let it sort of just do what it needed to for the forum. Interestingly, FF can view the pictures, but it is constantly locking up, not just here on cnczone, but youtube, and a number of other web sites. It's enough to swear off the internet and forums - well not quite, but certainly annoying.

[CarveOne]

FF v20.0 is working fine on two of my computers. No lock up problem or photo loading problems.

CarveOne

[harryn]

Hi C1, I have a perhaps challenging question to ask about your cut times and what contributes to them being long. The distances involved in any given cut are small, so it doesn't seem like cut velocity would be that big of a contributor. (but would be annoying to watch move the router across the table if slow)

I am just guessing but it seems like Z acel is the limiting time factor in cuting ? Is your software able to determine things like "if I changed my machine to double the Z acel time, would that save any cut time ? "

The reason I am asking, is of course assuming I ever get mine built and want to do projects like you have there, how much emphasis I should put on acceleration vs velocity. In theory, I can double acel at the expense of cutting velocity in 1/2. In particular, Z motion seems like it would be the most sensitive to this, but maybe not.

[CarveOne]

The only way to do a "what if" test is to change the settings and recalculate the tool path and then simulate it again. With a complex 3D model it can be a very slow process.

For the basket weave 3D Finishing passes I have it set for 150 ipm and the cutter only steps over 0.004" with each pass. The tool path uses the offset mode that starts in the middle of the knot pattern and works outward in a sort of circular pattern. Because of the knot weave pattern of the model surface the cutter makes a lot of vertical motions and not a lot of horizontal motions at a much reduced speed. Even though the actual feed rate is 150 minutes for a flat pocket area, when it encounters the knots the software dramatically slows down the feed rate to make all of the short vertical movements of jumping over the small ribbed features. I can raise the accel setting from 30 to a much higher number and lower the cut time but there is a limit to what the Z axis mechanics can keep up with without giving bad looking results in the material. A spring loaded Delrin anti-backlash nut on an ACME screw won't yank a heavy Z axis up and down as fast as a solid brass lead nut on the same lead screw. The brass will wear out sooner and start showing some backlash. There are always trade-offs. I run my accel and feed rate where it gives the best results for the project. A ball screw can operate with faster settings, but at more expense. Faster accel rates also make the machine shake more.

Very small step-over values dramatically increases the number of times the cutter goes around and around until it finishes the tool path. That increases the cut time more than just changing the accel rate. I'm using this small value only because of the tiny ~0.005" flat spot on the end of the V-bit, or because the 0.0625" ball nose cutter needs 0.005" step-over because an 8% step-over is a normal value for leaving no noticeable ridges due to the curved tip on the cutter.

Either way, this is about as good as I can get it with the equipment I have. Changing over to ball screws is not in my priority list anytime soon. If you build a much better machine you can get better results with this file and tweaking the tool path settings for best results with what you are running it on. I readily admit that I'm not the expert on this stuff and I'm not using the best tool path strategies and proper cutters. Using a V-bit for this is a good example of it. It worked well enough until I could get a couple of tapered ball nose end mills though.

I'm working on a 72" long coat rack with the basket weave. It's seven 5/8" weaves tall and is interrupted by six oval pockets for the brass hooks and a centerpiece with WELCOME Vcarved into a rectangular flat area. With the 1/16" ball nose end mill it will take 12 hours if I can't find a way to reduce it. If I use some simpler Vcarve design instead of a 3D model design it might take 1-1/2 hours max.

While typing this I'm running a V-bit test with 0.002" step-over just to see if the surface anomalies I normally get in simulation (and on the cut part) is reduced. Tool path recalculation time on a 2.3GHz AMD quad core machine with 8Gb ram could easily run 30 minutes with this machine.

Such is the price of doing large 3D modeling. The gcode text file may be as big as 2 Gb this time.

[CarveOne]

The gcode file with the 0.002" step over is 40.8 Mb, which is not so bad after all.