Clear Board Sensor?

[KeystoneChuck]

I have been running various projects and found something out about myself...I am not a painter. I have been using Pine with great results then I tried MDF with amazing results (I will be posting pics shortly) I read where someone painted the board then routed. I painted my MDF black and tried to route, got clear board sensor. Went on forum and read about keeping sensor clean and it might not pick up dark board to put on masking tape. I have a vinyl sign shop so I have access to large masking tape. I covered entire board with one piece of tape, trimmed edges flush and still will not cut. Put in pine with same project to see if it was a dirty sensor; cut perfectly. Can someone tell me what I could try. Don't know if it makes a difference 8" x 24" 3/4" mdf painted with flat black latex paint.

[bergerud]

Try a few layers of tape right at the ends where the sensor looks for the board edge.

[KeystoneChuck]

Does the color of tape matter? I am using a cream colored tape; I will try the mult layer. Where and when does the sensor look at the board. Should I be covering the entire board or just certin places. Does it look at the board further into operation or just when it is measuring?

[sk8nmike]

The color of the tape isn't as important as it's ability to reflect light. That's the problem with painting the board black, the sensor can't see enough of the reflected light to sense the board. Also lack of ambient light with interfere with the sensor. I keep a flash light near the carver and shine it on the board just under the z-truck when I get a board sensor error..

[KeystoneChuck]

Will try that next. My shop is like a dungeon right now. I have most of the lights ripped out. Was in the process of doing then my CW machine arrived, you can guess the rest. My wife says I'm like a bat out there :o)

[chkorte]

Does the color of tape matter? I am using a cream colored tape; I will try the mult layer. Where and when does the sensor look at the board. Should I be covering the entire board or just certin places. Does it look at the board further into operation or just when it is measuring?

When the CW measures the board it first measures the width at the point where you have the board loaded. Then it goes to the exact middle of the width and measures the length.You can put a single stip of tape across the width of the board anywhere more or less in the middle, but it has to be perfectly straght across, then put a piece of tape end to end in the exact middle length wise. when you load the board just make sure that the tape across the width is under the board sensor. If you have trouble keeping the tape straight use 2 pieces side by side. When you put the tape down on the edge of the board make sure you have a clean sharp edge. Don't let the tape stick out. Once the CW has the board demensions it won't look for them again.

[Digitalwoodshop]

So lets go over some basics...

The Board Sensor has 2 LED's or IR Lights like your TV Remote Control. It has a sensor transistor between the 2 LEDS that looks for the reflected light from the board. When the head goes off the end of the board the reflection is zero. This marks the board edge for the computer. So the painted MDF with Transfer Tape is still not reflecting enough light to see a difference between the board and the area past the board edge.

There is a Simple Test to tell the Health of your Board Sensor. Place a piece of white copy paper on the board and crank it down. On the Keypad select Options and Sensor Data and Board Detector. With the White copy paper the numbers should be about 156. If you get less, then you could have a dirty board sensor window, OR one or two of the LED's has snapped off.... Early Board Sensors got dust inside the plastic window because the green circuit boards were not glued to the plastic holder. The very thin film of Epoxy cured that.... All new Board Sensors have the glue and don't snap LED's or get dust inside. You can chop the back off a board sensor and fix them by then sliding the plastic window out... I just tape over the back to seal it, catching the plastic window to hold it in place.

A reading of 90 is a bad LED or a dirty window. Copy paper is a standard.... Every board is a different color..

Good Luck,

AL

[KeystoneChuck]

Dumb question...would painting the MDF with gloss black make a difference? I painted it matte just because that all the interior signs I do matte. But if it takes gloss to register I will make paint them gloss. Am I just making it harder because I'm using black? What if I used different colors burgandy, blue, green...? I'm sure my sensor is OK when I put piece of pine in , no problem. I can route raw MDF (dark brown/cardboard color) with no proble it just dosen't want to see the matte black. On a side note how many times have you guys been watching the CW route with centerline software and have you said to yourself "why the hell didn't it route that when it was there" Alot of time could be elimated if they give some thought behind their traveling routes.

[fwharris]

Dark wood and dark surfaces make it hard for the sensor to pick up the surfaces/top of the board. Do a test, put in one of your black boards and lower the head down to the board. Go to user options and do a sensor check of the board sensor. Remove the board and put in a pine and repeat the sensor check. I bet the black board will be a lot lower reading than the pine...

[dcalvin4]

Hope you probl. are solved
I ended up taking the plastic shield lens cover off and solved my problem of not finding the edge or end of the board maybe not the proper thing to do but it has worked for me..
Or between carves use a tooth brush to clean the lens, no taking off or taking apart lens just a couple swishes an see if this helps..
I have about 800 hrs ''on'' time and about 200 ''carve time '' due to this sensor prob..finally i renoved the lens cover and havent had a hiccup sinse
denny