The fit of this joint is critical, and the sample cut above was so tight I doubt there is any room for glue between the fingers. Considering using my 3 degree tapered end mill to make a tapered version that would drop together easily but fit tight when bottomed out.

World preview and first render in Aspire of tapered radial fingers:

The width of the ends of the fingers matches the width of the valley between.  Mating version fills the middle area although I could use the same pattern for the mating side. That presents options for what to do with the middle void.  A comment on my blog when I posted the first dowel splice joint was that the center could be a deeper hole and something could be hidden in the center.   My mind jumps to a tube with a cap, and inside would be time capsule artifacts. A note from the designer perhaps. To be found should the glue ever fail and the joint came apart. Only in one of 8 end caps. 

4D 

Edited April 6, 20251 yr by 4DThinker

3 hours ago, 4DThinker said:

joint was that the center could be a deeper hole and something could be hidden in the center.   My mind jumps to a tube with a cap, and inside would be time capsule artifacts. A note from the designer perhaps. To be found should the glue ever fail and the joint came apart. Only in one of 8 end caps. 

Cool idea. My guess it would be many, many decades it ever that joint would fail under in natural environmental circumstances. GOPHER-IT!

6 minutes ago, Grandpadave52 said:

Cool idea. My guess it would be many, many decades it ever that joint would fail under in natural environmental circumstances. GOPHER-IT!

Found some .6" diameter glass tubes with caps.  .6" diameter and 2.25" long.  Room in the middle for one.  About 24$ for a case of 24.  I know what I can do with one, but not with the 23 others. 

Test cut of the tapered radial finger joint.

Slipped together about 1/2 the way.  A few taps with a mallet and then the bar clamp tells me it is just a bit too tight.  These settings would work if I didn't want to glue the caps on, but I fear time and board shrinkage/swelling would let it pop off.  Need to allow a little room so glue doesn't squeeze all out when clamped shut. 

The gaps left I think are due to some debris left in between.  Too anxious to test the fit. 

4D 

That looks cool.

Slow progress, but 2 legs standing with stretchers between them. 

Odd thing happening when the CNC cuts the tapered  tenon on the 5/8" stretcher ends.  As the bit goes around the cherry dowel it does a little flat spot on the opposite sider of where the alignment dip is.  No evidence of that flaw in the toolpath preview.  Not a serious flaw as it is hidden when the tenon is fully inserted. 

4D

Looking awesome thus far 4D.

Working on the upright slat dowels today and it appears the odd behavior is a failing backlash nut on my X axis.  Have contacted Probotix support to see if they still have any replacements. 

4D

Unscrewed the anti-backlash nut and backed it out only to see a pile of gray dust drop on the bed.  The plastic used for the nut has apparently reached the end of its lifetime warranty. Haven't heard from Probotix yet, and know their new designed CNCs don't used the same nuts, and their website only sells replacements for the new ones at $99 each.  Found some that might work at McMaster Carr for $57 each. Ordered 3 since I know the Y axis nuts will also need replacing.

Such is the peril of owning my own CNC and enjoying using it. 

4D

Len's not selling parts for the older models?

1 minute ago, honesttjohn said:

Len's not selling parts for the older models?

He referred me to McMaster Carr for the radial axis belt, and hasn't replied about anti-backlash nuts for the older Galaxy models. Both have changed on their new models.  Noticed on their web site the older models had a 2-year warranty, but the new ones claim "lifetime warranty".  Suspect they've learned over the years where the flaws were on their older models which cost them quite a bit to replace parts on.  Many of the flaws I pointed out to them as a heavy user of their CNCs in the college shop I taught in. 

4D

The new anti-backlash nuts came, and although the internal threads work the flange holes don't match and the outer diameter of the shaft won't fit into the bracket on the meteor.   Now looking at one from Roton which looks the same and is the same diameter/hole pattern, etc, but I can't verify from their web site that the threads will match.

Emailed them for verification.  Now waiting on a response.

4D

Looks like the anti-backlash nuts from Roton are a match.  I'll know for sure when they arrive in a  few days. Their sales dept. confirmed for me that they have 4 starts, are 8 threads per inch, and pitch is 1/2" movement with one 360 degree turn.   I'm not sure that Z axis uses the same nut so I ordered 3.  One for the X axis and 2 for the Y axis lead screws. Anyone with an older galaxy class CNC from Probotix still in use I'm pretty sure these are the nuts they used. 

4D

New anti-backlash nuts arrived today.  30 minutes later I had the old ones out and new ones in. Same gray dust from the old Y axis nuts when pulled out. Sprayed the threaded rods with some silicon spray then ran the CNC back and forth each direction to spread it down the threads. 

Tried cutting the same file that showed the flaws.  X axis movement was correct.  Y axis movement still looks like backlash.  Suspect a coupler between steppers and threaded rod may be loose. Shut down the CNC for today to contemplate what else might be the cause.   

4D 

Edited April 22, 20251 yr by 4DThinker

Cracked the Y axis coupler set screws loose, turned them 90 degrees, then cranked them in tight.  Ran a less critical job and all the parts turned out the shape and dimensions they were programmed to be. So the flaws must have be due to one or both stepper motor couplers being loose.  Making a clamp on trim router table to clamp to the edge of my bench. One of my Milwaukee trim routers came with a larger base that has perimeter holes intended to be used in a table or fixture/jig.  Had a piece of 12mm baltic birch plywood with enough area to cut all the needed parts from.  Good excuse for it. I'll post it in a new thread here when completely done.  Still a few steps left to finish it. 

4D

Now that I've got the CNC running well again, I'm slowly working on finishing the parts and joinery for this dowel table base.  Two sides done. Back will also have 4 vertical dowels.  Front just two stretchers.  Looking for some zebra wood I can use to add into the composition.  Sides of the drawer maybe, or perhaps just a stripe down the middle of the cherry top and low shelf.  Something to echo the zebra caps on the leg ends. 

4D

On 4/29/2025 at 9:15 AM, 4DThinker said:

perhaps just a stripe down the middle of the cherry top and low shelf

I like that idea or maybe even as an inlay around the top perimeter?

I ordered some "red zebra wood" from Amazon.  Supposedly a relative to Zebra wood with the same dark stripes but a more red background than the tan/yellow normally seen in zebra wood.   Less expensive too.  Wondering if the red hue better matches the cherry wood.  Might do the drawer sides but not the front or back, and trim the sides of the top and shelf.  Keep the capping theme started by the zebra ends of the legs.

Small steps forward. Now all 4 legs are connected. Still to come will be the bottom shelf, a drawer and rails it slides on, and a top. 

Rear stretchers may still get vertical dowels between them like the sides.

4D 

Looking great 4D. I like the idea of adding vertical dowels between the rear stretchers.