Z Homing in 3D Models

Hi,
Made this xmas plaque in VCarve. When I make the bit change to the 90 degree v-bit for the text onto the banner, I would home Z to the original place where I homed Z to when I set up the work piece for the 2 stage cuts. Am I correct?

If there’s something you see in the picture I could do better, by all means I am thankful for any suggestions. Thanks so much! Stefan

You are correct. Home the new bit where the first bit was homed.

It looks like your finished piece tapers down at the edges. This is fine and is likely to be done with your v bit. I find that it is sometimes a good idea to first profile cut around the piece with an end mill (leaving the work tabbed in place) so that the v bit has an easier time cutting the piece. Stating this another way, with the profile cut complete, the v bit only has to cut the work piece and not also the part that is removed. This may not be an issue for you but for very deep work I find this helps.

Thanks Harry.

I am not sure I understand 100%. But … I ran a roughing cut first, which took most of the material out along the edges. And I have a cutoff that I am running last with a straight bit.

But first I have to order a powered USB hub and shielded USB cables. I ran the router (Makita) faster (4 - 5) for the roughing and the darn thing quit on me 4 or 5 times yesterday. First time this happened in a long time. I did all the usual as far as computer/power setup, but that didn’t do crap for me. Already ran a dedicated power line for vacuum and router. Since I usually run the router at the lowest setting I am thinking that’s got to be it.

Yes, higher RPM = more RF noise.
I use the Makita as well, I dont need more than 16k rpm (#3) for 100ipm in MDF (1/2» DoC) and is plenty.

Well, I think I can say that in my case it was the RF noise generated by the Makita that caused the infrequent shut offs, or to be more precise, interruptions in the transmit of the data. I ran a 3.5 hour cut of the above without any issues today,had the router set at 1, and ran 70 ipm. Took a while.

Blows my mind! You would think that as soon as you hit a certain speed (and with it the generated noise), that the machine quits. Though that doesn’t seem to be the case. Quite puzzling to me. Should have recorded the session and re-watched it to know for sure. But it’s already been too much agonizing mental torture that left severe mental scarring. LOL

I still got the powered USB coming. I want to find out what happens once the data runs through it.

BTW, I had the same crap happening when I was running the DeWalt at higher speeds. Once I learned a little bit more about feed rates, step over, DOC and so on I realized I was running the router way to fast. Eventually I ran everything on setting #1.

Lastly, I know I miss-spelled Christmas. LOL I corrected that of course. LOL

Check out my latest post under troubleshooting for this issue…
It’s normally a simple fix.

Appreciate that. I did read your post. I have done all, if not, most of your suggestions. I took my time assembling when I got my unit. Was easy to do since everything came piece meal and took weeks before I had everything. The controller came first. Not that I am an expert, but I still build my own desktops (for graphics, video processing and stuff), so I am aware of the importance regarding seating connectors properly.

I ran a separate 20 amp circuit from the breaker box to feed the router and vacuum. The vacuum hose is grounded. Computer and controller are on the same circuit protected by a surge protector. I did all the suggestions I found in the forum regarding computer power settings etc., including running Easel on Chrome.

As I said, I’ve had these issues regardless of which router I ran. What I know is that the DeWalt I ran way too high (inexperience), especially in the beginning. It took a while, I want to say about 3 months, before I got into longer cuts. That’s when I first ran into this particular problem. Since I abused the DeWalt so much, the brushes wore out pretty quick, and I replaced them. Turned out that wasn’t it. Simply didn’t come back on. Factory sent me a new one, but I didn’t want to wait, hence a trip to the store and purchased the Makita. The Makita I never ran as high, between 1 and 2. Did a lot of reading here regarding cut settings etc.

Until I did this project. I wanted to speed up the roughing cut (1/4" bit, speed on the router set at I want to say 4.5 - 5.5, and increased the feed rate. Let it run and at about 25% XCarve stopped. I reset, let it run again, same thing. Reset, this time deceased router speed to 4 and adjusted feed rate. Ran to 72% this time and then stopped. Gave it 2 more tries, same thing. In the end, adjusted router down to 2, decreased feed. This time it ran through. You can imagine, at this point I had spent some significant time in the garage.

Anyhow, the detail pass was slated in VCarve to run for about 2.5 hours. After I made the necessary adjustments it took almost 4. But it ran through.

Sorry, it’s such a long story btw. Knowing what I knew now after all the fixes I applied (tried) I have come to the conclusion that this is not a power issue (in my case) due to the fact that the stoppages occurred at the same time depending on the router speed settings. That leaves me with the signal flow and subsequent interruption of it. At least that’s where I am at, at this point.

I may not need the powered USB hub at all. The reason I want to try it regardless, is because I am curious now and want to see if the XCarve stops at higher router speeds even with a hub. My experience (past and current) seem to point toward RF noise interference.

While I am not an expert, most of the things discussed in this forum regarding this issue are pretty logical and common sense. I certainly learned a lot more about this than I wanted to. There’s a lot of things going on when working with a computer, XCarve, Controller, and imported gcode, besides the usual stuff like dirty power, line overload and so on. Pinpointing a problem like this can be different from user to user in my opinion, because no setup is the same.

All one can do is start with the least expensive and work your way through step by step. For my part I appreciate the tips and guidance here. It helped a lot, and I learned a few other things along the way.

Ok. From what you describe, I would check the wires in the loom chain.
The wires going to the stepper motors, limit switches, z probe, etc., should all be SHIELDED wire that contains a foil wrap and a drain wire (a bare, uninsulated conductor). In lieu of this, a twisted pair cable can be used, but not for the motors. Motor wiring MUST be a shielded cable.

When hooking up the shielded cables to the motors, it is extremely important to ensure that the drain wire is connected properly to an earth ground on only the controller end. There should be no connection of the drain wire on the motor ends.

When connected properly, the drain wire acts as an antenna to draw errant rfi and efi signals directly to ground. If connected on both ends, it cannot pickup the errant signals and does not function.

You don’t mention if you have an IOT relay or not, so I assume you do not, but that should also be a twisted pair or shielded wire if connected. Try disconnecting the relay and running those items manually.

If you use a Z probe, make certain that you disconnect the probe completely after setting Z height.

In addition, a ferrite core can be added to the router’s power cord to further reject errant signals. Do this as close to the router as possible. Make sure the router power cord is straight in the drag chain and not wrapped around any of the motor wires. Try to keep the power cord separate from all other wires inside the chain.

The dust collector should be powered by a completely separate circuit from both the router and the controller. In an ideal world, all 3 would be on separate circuits, but in most cases having the router and the controller together should not be a problem. Having 2 motors running on the same circuit is a big no no, due to overload and a/c current backfeed issues.