Clock body in oak - 3rd time lucky!

[Lazarus]

Set my cnc up to carve out a clock body from an art nouveau template I imported into Carbide Create.
1st attempt it went haywire due to poor programming (guilty as charged)
2nd attempt the wood split down the grain whilst removing some surplus with a chisel (ham fisted)
3rd attempt - toolpaths modified, vaguely successful, just waiting for the clock face to be made from a ceramic tile and laid into the pocket. Give it a coat of homemade wax and it don't look too bad for what was once a leaf from a drop leaf table.
Torn between a wall clock and a mantle clock if I add a base to it.

 

[Ollie78]

Nice work, I like the flowing shapes. Hard to tell from the picture but it looks like you may be getting a bit of burning. To avoid this try going a bit faster (linear speed not rotational) or sometimes leave a half mm for a final clean up pass. Not sure if carbide does this funtion natively, I mostly use vectric which has "separate last pass" as an option for profiles at least, not sure if it`s on does vcarves.

Ollie

 

[Lazarus]

Nice work, I like the flowing shapes. Hard to tell from the picture but it looks like you may be getting a bit of burning. To avoid this try going a bit faster (linear speed not rotational) or sometimes leave a half mm for a final clean up pass. Not sure if carbide does this funtion natively, I mostly use vectric which has "separate last pass" as an option for profiles at least, not sure if it`s on does vcarves.

Ollie

yeah there's a touch of burn there. I have a bastardised cnc 3018 Pro with a Makita palm router strapped on and I'm a bit of a novice with this sort of thing. The machine wouldn't handle much more in terms of linear speed, I already had it running at the heady heights of 370mm/minute!
I'll look into the final clean up pass option.
Thanks for the advice.

 

[Ollie78]

yeah there's a touch of burn there. I have a bastardised cnc 3018 Pro with a Makita palm router strapped on and I'm a bit of a novice with this sort of thing. The machine wouldn't handle much more in terms of linear speed, I already had it running at the heady heights of 370mm/minute!
I'll look into the final clean up pass option.
Thanks for the advice.

There are calculators to find the right combo of flutes in the cutter, spindle speed and linear speed. If limited by machines linear speed you could either slow the rotation or reduce the number of flutes in the cutter.
For v carves I do 2000mm/min with a 2 flute cutter at 20k rpm roughly.

I have found that solid carbide engraving specific cutters very much superior to "normal" router bits for a couple of reasons. Firstly the geometry, the flutes are angled slightly rather than straight, secondly they are sharper.
These are the type of cutters I like, super sharp last ages Amana Tool Solid Carbide End Mills - Engraving - V-Groove - Ooznest
can be found in "generic" brands on Amazon as well.

For small work the flat single flute v bits for pcb`s are really good, can be found very cheap on the usual places. like these

Ollie

 

[Fergie 307]

Know nothing about cnc but repair quite a few clocks. Only observation I would make is that typically this sort of decoration is very shallow cut, only a couple of mm. Ĺòoks like you have gone a lot deeper. A shallower cut might overcome the burning, and would also leave more material around your cuts. I would worry a little about splitting in the future where the cuts are very close to the edge.

 

[Lazarus]

Know nothing about cnc but repair quite a few clocks. Only observation I would make is that typically this sort of decoration is very shallow cut, only a couple of mm. Ĺòoks like you have gone a lot deeper. A shallower cut might overcome the burning, and would also leave more material around your cuts. I would worry a little about splitting in the future where the cuts are very close to the edge.

Cheers mate I'll bear that in mind for the future. I know there are often shallower cuts but I'm just enjoying the experimentation at the moment!

 

[Lazarus]

There are calculators to find the right combo of flutes in the cutter, spindle speed and linear speed. If limited by machines linear speed you could either slow the rotation or reduce the number of flutes in the cutter.
For v carves I do 2000mm/min with a 2 flute cutter at 20k rpm roughly.

I have found that solid carbide engraving specific cutters very much superior to "normal" router bits for a couple of reasons. Firstly the geometry, the flutes are angled slightly rather than straight, secondly they are sharper.
These are the type of cutters I like, super sharp last ages Amana Tool Solid Carbide End Mills - Engraving - V-Groove - Ooznest
can be found in "generic" brands on Amazon as well.

For small work the flat single flute v bits for pcb`s are really good, can be found very cheap on the usual places. like these View attachment 144676
Ollie

Thanks mate, I need to look at some better cutters I'm using bog standard router ones atm. My Makita clone will only go down to about 14000 rpm I reckon, although sharper cutters would enable a faster feed speed I'm guessing.

 

[Lazarus]

So I got it finished at last. Laser etched ceramic tile face, carving finished with blackboard paint and waxed afterward to give an ebonised effect.
Not too bad.