Touch probe moving

Is anyone else seeing the touch probe move during probing? I see this on the first contact on the touch probe on X and Y. The second contact doesn’t look like it moves it, but it is also going at a slower speed. Maybe moving too fast initially.

Does anyone else see this?

Maybe I need to hold the plate against the wood with my hand.

I noticed that too on the X and Y probing. Now I just hold onto it while probing. It’s an easy fix.

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Hey Garrett… You can try adjusting the speed in the probe settings. Slowing it down may help. https://youtu.be/jsiKYUPfeUM

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Thanks, I’ll try that.

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I think the default seek or probing feedrate is set at 200 mm per minute. I would suggest a absolute maximum of 125 mm/m for the fast seek You can edit the probe feed rate on the Settings page in the controller.

What is happening is at 200mm/m (7.87 inches per minute) the machine cannot react quick enough to stop the probing when it first contacts the touch plate. Holding it with your had most likely does nothing but give the appearance that it didn’t move. If it still moves at 125 try dropping the fast probe speed down to 75 and you should be be able to achieve a very repeatable 3 axis zero every time.

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I changed to 125 and it looks to be working much better. Thanks.

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Is there a way to set the start point of x and y to be further from the probe before seeking? My spoil board flattening bit for example is colliding with the probe when it transitions from z to x.

Spoil board flattening is the one instance where the touch probe is most likely not going to work because you cutting at the very extremes of the cutting area. Try using the eye ball/paper method for wasteboard flattening.

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Default Probing speed will be decreased to Charlie’s suggestions in the next update.

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Some bits are not “Touch Plate Friendly” such as a large diameter bit, tapered ball nose bits, and some large diameter V bits. There is a simple work around to remedy this and still achieve an accurate 3 axis zero with virtually any bit you are likely to use.

When you have a bit that is not “Touch Plate Friendly”, simply start with one that is and zero all three axis as normal. Then swap it out with your bit that is not “Touch Plate Friendly” and ZERO JUST THE Z AXIS with it. It may not fit inside the target circle and most of it may be hanging over the edge of the touch plate but that is ok. the part of the unfriendly bit that touches the top of the touch plate is inside the target circle, the rest of it can be hanging over the edges of the touch plate.

How does this work? Simple. When you zero all three axis with a friendly bit your origin is set for all three. Then when you swap out to the unfriendly bit and zero just the Z axis your X and Y axis are unchanged, only your Z axis height is modified. X zero and Y zero will always be the same regardless of the bit diameter because X and Y zero is based on the centerline of the spindle, not the diameter of the bit. Your CAD software takes all this into account when you specify the bit you will be using for any particular tool path.

So you could set your x y zero with a 1/4 inch bit, then switch it out with a 3 inch fly cutter and zero the Z as long as the tool path you run was designed for the 3 inch fly cutter.

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It seems to me like the touch probe is designed backwards. Its seems like you would want to probe in the opposite direction, so if the bit does bump the probe at all it is just snugging it further against the corner of the material rather than potentially pushing it away from the corner. Even if the bit is probing really slowly there is always the potential to move the probe and throw off measurements if it is traveling in that direction.

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You’re right…it is backwards compared to other systems. @charleyntexas can speak to this better than I can, but Onefinity is making a trade-off:. You gain the safety of not breaking a bit if a probing mishap happens (driving the bit into a non-moving probe) and it lets you probe so the corner of your workpiece is at the machine’s full front-left corner for maximum cutting area. I don’t have personal experience with this machine yet, but it seems these are the pros and cons of this method.

There are very good reasons for performing the touchplate probe in this direction. Charley already posted a great explanation as to why this approach was taken, it can be read here:

I can assure you that once you adjust down to the 125 rate (which the new Firmware last night 1.0.5 changed by default) the probing backwards has a ton of benefits. In my world I can give you one that personally has saved me $100’s. If you use the dust boot sometimes when the router goes low it can remove the magnet from the router shaft. In this case there is no complete circuit when contact with the TP happens. If you are using a thin bit it will push the touchplate away from your work and save the bit. If you press into your work that is secured down, snap and there goes a $35 bit.

IMO doing it in reverse was a genius decision/implementation.

-Alex

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I think this is right place for my query. As i want to know best cnc touch plate. I am looking to purchase one but i haven’t great amount of knowledge on it. I search on google and selected 2 of them from article after seeing their pros and cons.

1st is of. CNCTOp and 2nd is of Magic & Shell.

Now i want to know which one is best. You can also recommend any other.

Also willing to know what factor decide which is best apart from pricing

I recommend the Triquetra sold through Onefinity. Works perfect and the controllee is already set up for it.

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Totally agree, I do not think there is a better TP out there. Plus… Native Support and design is never a bad idea. Been using Triquetra touch probes for 4 years now and have had nothing but excellent results.

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I had the same problem… I now hold the plate to make sure it does not move and then get my hand out of the road when it finishes

I tried this, brought down to 75 and still not working

THIS! First time I probed, I was holding it, exactly for the reasons described above, hadn’t paid attention to the probing instructions yet. Probed, then WHAM, end mill almost shaved off the top of my finger. The rapids on the X0Y0 seriously need to be slowed down for this operation.

One thing I noticed if using bits that are painted shanks or painted surfaces on them for instance a cmt v groove it will not conduct unles it hits on a cutting face. So another thing to watch out for when using painted router bits.