Board sensor

[Dennis McDonald]

Does anyone know if there is a adjustment for the diode. Mine will not work on Walnut or any dark wood. After going through the trouble shooting in the manual I get a reading of 30, and according to the manual it should read at least 90.

I keep getting a (clear the board sensor)error on the darker woods. The machine will find the wood if it is Oak, pine, fir, and Mdf. The tape trick is somewhat hit or miss, maybe because I am a novice with machine. Although I did not just fall off of the Turnip truck. I am a retired Toolmaker that made molds and dies for the Electronic connector industry. So CNC is not totally new to me.

Needless to say I have tried to contact CarveWright, I never got past hold today, and they have not called back, or answered a email. I thought maybe someone out there might be able to give heads up on my problem. Also does anyone know how much they charge for a new sensor?????

I have been running without the lens and getting by, but we all know that it will possibly catch up with me in time.

Looking forward to hearing from you folks out there. I have been reading the Forum since I got my machine and am very impressed with the knowledge base that it contains.

Dennie

[Bubbabear]

try painters tape around the edges

[pkunk]

Sometimes when mine has trouble with a dark wood, more light (even a small flashlight) allows it to read OK.

[Dennis McDonald]

Thanks for the tips (blue tape and flash light)

I thought maybe that I was a little goofy the other day, because I had the machine sitting in the morning sun and it found and caved a walnut boad, so it makes sense with your flashlight trick.

I am retired from 3M, so will get some of that high priced tape that is paying in part for my retirement. Ha Ha

[LollyWood]

Dennie,

I use ALOT of walnut and darker rosewood in many of my projects. When my "toy" would not read / find my boards due to it's darker color, some masking tape (double layered) and a light over the flex tube slot seems to work. I'm also a CW Rookie. The thing may have a few gremlins, but there not very smart gremlins. The Pros around here have been fool'n em for a while. Most every problem you and I will encounter is pretty old hat to these folks. Just ask them, someone will have had the exprence and are always willing to help. Hope this helps.:)

Merry Christmas,

Bernie :^)

[jwhllh55]

You will get the hang of using all the tricks, but sencors do fail. As a matter of fact any dust in the back of the board will short the sencor out and give a bad reading. I have replaced mine a number of times. Just keep calling LHR and they will be more than happy to take care of your problem no matter what it is. With the holidays, they are very busy, so give them a break.

[benluz]

Yes,I have has board sensor problems after just one Walnut board and dark sawdust was behind the the lens, despite the fact that I sealed it with silicone all around the edges inside where the circuit board is ,every crack and crevice. I took the plastic lens out and now use HVLP air line from my spray system to blow off the sensor,sometime using my finger to increase the pressure some,compressed air may damage it without the lens,since doing this I have not had to remove the sensor for cleaning at all.
Ben

[Kenm810]

Any one happen to know what the screw -- bolt sizes and thread count on the 2 that hold the Board Sensor in place on the bottom of the Carving head.
I called LHR and told the tech the sensor had dropped free, was damaged and hanging by the wires, one screw was striped and the other was missing.
The tech said He would send the the new sensor and screws right out, that was November 30th.

Well the Board Sensor came in the mail yesterday --- yep you guessed it -- No Screws.
So I'm looking for the sizes so I can find a couple to use and get the machine up and carving in the mean time,
while I wait for the ones from LHR to arrive.

Their somewhere around 4-40s About 3/8" to 1/2" long

[crawls]

Ken,

First I would like to apologize for not sending the screws with your board sensor. The board sensor screws are M3's.

All,

Another thing to look for in regards to low board sensor readings is head pressure and I'll explain why. The board sensor has two angled emitters and one necked detector. We neck the detector for accuracy, and thus need two emitters to get the intensity up. The emitters beams cross each other at the surface of the board when the head load is 70-80lbs. If the head loading is low, the beams cross above the board and if the loading is too high than the beams cross below the surface of the board. Both of these cases will result in lower intensity (board sensor reading). Also note that the board sensor determines the edge of the board by going from a high to low reading, or visa versa. During this transition, an s-curve is received form the sensor in which the mid-point of the s-curve is set as the y or x position of the edge of the board. By using a flash light, you may falsely shift the s-curve upward and induce error into the edge detection. Granted this error may be small and it may not be noticeable in most projects. I just thought I would mention that in case your project requires as much accuracy as possible.

I would not recommend using a board sensor without a clear window. It will eventually clog to point of no return. One thing that the manufacturer is doing to prevent dust contamination is putting a beard of silicone or hot glue around the green circuit board and the housing that contains the emitters and detector. This will prevent dust getting into the housing and it will strain relief the legs on the E&D's. One final note, we apply offsets to the board edge calculations to account for vertical inaccuracies (both yaw and pitch). So when you remove your board sensor, it is best to run the "user calibration" under the options menu. This will recalculate these offsets. Now, it is not always necessary to run the "user calibration", just suggested.

[Kenm810]

Chris,

Thank you so much for the explanation of how the board sensor is aligned
with the surface of the project board in conjunction with the roller pressure,
plus how it is effected by the use of additional light, possibly causing additional faults and errors.

I personally appreciate you taking time to acknowledge the problem I'm having with my machine.
And I am alway sure LHR will come through for myself an others as they have over the past year.


Thank You Again

[Digitalwoodshop]

Thank You for the enlightenment on the board detector.

AL

[dragoncarver]

now my board sensor is reading 62-63 when not over the board and when i take the board out the cover has fell off i is now gone after reading this blog i think clening may get me by till i can send it to texas for repair:(