Height Sensor Problem

[Woodhacker]

I have checked the forum, but cannot seem to find out anything about this.

I cleaned my machine and wanted to start a new carve. All goes well until it goes over to the side to check the height thingy. I have the tab kept in place with a piece of foam. The bit (16" carving) does not make contact with the tab. Then it either goes back to the other side and starts the sensing again or I get a msg saying bit height does not match. I get two options: check height again or, ignore. Neigher of these helps. If I choose to redo the sensing the same thing happens. If I choose ignore it starts an air carve. It is starting to make me crazy!!

Anyone have any ideas on how to get back to carving wood instead of air?? Thanx to all in advance.

[Digitalwoodshop]

So if I get this right, the Z goes far enough to reach the bit flag as you have a piece of foam holding it out. It just stops EARLY before touching the bit plate....

It is happening because the current in the Z Motor is getting higher like it touched the bit plate but did not....

Look for Wood Chips in the Z Belt

Look for dirty bearings or Bearing rails for the Z. Especially the area BETWEEN the upper and lower roller, the area you cannot wipe with the head all the way down or up... The NO mans land in the middle you need to shove a rag in between the bearings and move the head up and down to clean.

OR.. The Z Motor gear box is binding.

You have the New Z right? The OLD Z did this.....

AL

[Woodhacker]

So if I get this right, the Z goes far enough to reach the bit flag as you have a piece of foam holding it out. It just stops EARLY before touching the bit plate....

It is happening because the current in the Z Motor is getting higher like it touched the bit plate but did not....

Look for Wood Chips in the Z Belt

Look for dirty bearings or Bearing rails for the Z. Especially the area BETWEEN the upper and lower roller, the area you cannot wipe with the head all the way down or up... The NO mans land in the middle you need to shove a rag in between the bearings and move the head up and down to clean.

OR.. The Z Motor gear box is binding.

You have the New Z right? The OLD Z did this.....

AL

The bit goes all the way to the bit flag...and goes down a little way toward it. Just doesn't touch it.

There are no chips in the Z-belt and the no-man's-land area was cleaned out with a clean rag when I cleaned the machine.

I don't think the Z Motor is binding. The head goes up and down very easily...and back and forth across the carve area.
I believe I have the new Z. It does not have the probe plug in it. If I remember correctly, it is a "B" model.

I have read the forums diligently, but can't seem to find anything that I have not already addressed. I KNOW I will get some help, and am sure it will solve my problem.

I have carves to do...don't need that thing sitting there sulking at me...lol
Thanx for the reply.

[unitedcases]

I would take a look at the encoder in the back of the z-motor. I had a problem like that once. If you choose to look there are three screws that hold a black "cap" on the back of the motor. Pull the cap and blow it out gently, dont touch the encoder itself. Maybe be a shot in the dark but you never now. Other than that I would wipe the memory card clean and then reload the project. Sometimes they bugs that noone can explain.

[Woodhacker]

I would take a look at the encoder in the back of the z-motor. I had a problem like that once. If you choose to look there are three screws that hold a black "cap" on the back of the motor. Pull the cap and blow it out gently, dont touch the encoder itself. Maybe be a shot in the dark but you never now. Other than that I would wipe the memory card clean and then reload the project. Sometimes they bugs that noone can explain.

Not too sure how to get to the encoder. Does it entail taking the z-motor off or apart??? Even though I see quite a few folks tearing their machine down to just pieces, I don't know if I am that confident in my getting it all back together again. When I do mechanical work I ALWAYS have pieces left over...lol

[fwharris]

Not too sure how to get to the encoder. Does it entail taking the z-motor off or apart??? Even though I see quite a few folks tearing their machine down to just pieces, I don't know if I am that confident in my getting it all back together again. When I do mechanical work I ALWAYS have pieces left over...lol

Richard,

You will need to take the top cover off of the machine to get to the z motor. Once you do that do as Unitedcases said to take the back cover off of the z motor. You do not need to take the motor off to do this...

[Woodhacker]

Richard,

You will need to take the top cover off of the machine to get to the z motor. Once you do that do as Unitedcases said to take the back cover off of the z motor. You do not need to take the motor off to do this...

I was a little apprehensive about the process, but it seem pretty straightforward. I will give it a whack tomorrow. Thanx.

[Digitalwoodshop]

I am thinking you should try a few more things before messing with the encoder....

The key in my opinion is in your statement that the head goes right and stops at the bit flag and starts going down to touch the bit flag.

Here is the key.... What tells it to reverse is a increase in Z Motor Current that the computer is monitoring. When it detects a bump or increase in current the computer tells the Z motor to reverse direction.

Something is causing the spike in current.... So it could be the encoder but not likely....

First I am going to need you to run a project again but if and when it gets to carving stop, shut the power off and start over. I need you to watch the bit flag touch and be looking down the flex shaft slot. Something as simple as the top black cover not installed properly and the FLEX SHAFT hitting the side of the black cover slot on the way down.

If that does not do it then do this.

I am going to need you to wipe down the Z rollers one at a time. Do this by holding a rag to the roller and moving the Z up and down. Especially clean out the U shape of the roller bearing. A Speed Bump of sawdust on the roller or rail is all it needs to provide that current jump.... Look close at EACH roller.

Next is removing the top cover and remove the Z Motor and look over the Z belt and Gear Box for contamination.

That will keep you busy...

AL

[mtylerfl]

AL,

Just wanted to say you are a much appreciated resource. I think everyone here has learned something from you at one time or another - or learned a few hundred things from you, like I have!

When AL talks - people listen!

Thanks for being there for all of us.

[Woodhacker]

I am thinking you should try a few more things before messing with the encoder....

The key in my opinion is in your statement that the head goes right and stops at the bit flag and starts going down to touch the bit flag.

Here is the key.... What tells it to reverse is a increase in Z Motor Current that the computer is monitoring. When it detects a bump or increase in current the computer tells the Z motor to reverse direction.

Something is causing the spike in current.... So it could be the encoder but not likely....

First I am going to need you to run a project again but if and when it gets to carving stop, shut the power off and start over. I need you to watch the bit flag touch and be looking down the flex shaft slot. Something as simple as the top black cover not installed properly and the FLEX SHAFT hitting the side of the black cover slot on the way down.

If that does not do it then do this.

I am going to need you to wipe down the Z rollers one at a time. Do this by holding a rag to the roller and moving the Z up and down. Especially clean out the U shape of the roller bearing. A Speed Bump of sawdust on the roller or rail is all it needs to provide that current jump.... Look close at EACH roller.

Next is removing the top cover and remove the Z Motor and look over the Z belt and Gear Box for contamination.

That will keep you busy...

AL

and Mike. I will try this. It could be that there is something I missed there in no-man's-land. I try to keep the machine clean. Don't have a DD or DC as of yet. I usually stop the carve every half hour and hold on to the QC with one hand while using the shop vac with the other to clean out all the sawdust I can get to.. Most times, after the carve is finished, I take the rig outside and give it a really good blowing out with the compressor. I sure hope I can get this thing up and running. The help here on the forum is fantastic. You guys (and gals) are great. Thanx for the input.

[Digitalwoodshop]

Thanks Guys:mrgreen:

It could also still be just one single wood chip caught in the Z Belt or Cogs of the lower pulley. It only matters when the computer is looking at the Z Motor current waiting to reverse direction. This sensitivity is set to just touch the bit plate. Less sensitive then it will drive the pointed tip of the bit into the metal of the bit plate. A fine line between too sensitive and getting false reverse or less sensitive and smashing the bit into the metal.

I agree.... It could be a speed bump of sawdust pitch stuck to the rail in no mans land... You can't clean no mans land unless you push a rag inside between the upper and lower rollers.

I just saw your located in Flordia so Humidity and dust could be a issue causing speed bumps on the bearings and rails or belt.

Good Luck,

AL

[Digitalwoodshop]

It's hard trying to be a Remote Troubleshooter.... I read the symptoms posted and try to visualize the symptoms and using a process of elimination come up with the most common or most sensible reason why the problem is being caused. Then come up with possible ideas on why it is happening and try to describe them so the person with the problem can possible fix the problem OR someone later reading this because of a search learns something.

Knowing the right questions to ask is part of the game... I remember this joke about a Microsoft Tech talking to a customer about why Her computer would not start up and the display was blank.... They went through a few things with no luck... Then the Tech asked if she had closed all the Windows before she shut down the computer the last time she used it.... She then replied that she had the Window Curtain open as the power was off in the building. The tech asked... You mean the POWER is OFF in the BUILDING and NOTHING IS WORKING? She said Yes? O'...... Click...:roll: She hung up....

So sometimes knowing the right questions to ask is the most important thing. I don't have a play book to read from like the LHR Techs do...

So lets get this machine working and get back to carving....

AL:rolleyes:

[Woodhacker]

I started taking the top off the machine. Got the 4 screws out and the top is loose. However, there are two sets of wires still holding it in. I think they are for the door switches. How do ya get em loose??? As time goes by, I will eventually get to a point where I can strip the thing down to a couple hundred pieces on the table and get it back together, but for right now, I am gonna go as slow as I need to!! I DO appreciate the help. Just don't stop providing it or I will have a half-disassembled machine and not know how to put it back together again...lol Thanx!!

[AskBud]

Here is a PDF.
AskBud

[Digitalwoodshop]

The PDF is good....

The wires go to the right side cover switch on the right and the left wire goes to the left cover switch. The left switch tells the computer you opened the cover. The right switch is in the return path for the cut motor power and prevents the motor from running when the cover is open.

A word of caution about the left wire... It can be plugged in 180 out then you get a open cover error. White wire toward the center of the machine.

The Right wires can hook to either wire as it is just a in out of the switch. What gets people is when you put the cover back on you MUST be sure to push the right wires back into the corner. If you don't then the cooling fins on the Z Motor can hit the wires and prevent the Z from reaching the Bit Flag. Then the Bit Flag will not extend and you will get a Load Bit error....

Good Luck,

AL

[Woodhacker]

You guys are da bomb!! Not only explicit directions, but a picture book too. How can I go wrong now??? Thanx heaps ya'll.

[Woodhacker]

...that I need further instruction. I have located the wiring plug-in, but cannot get it loose by just pulling on it. Is there a lock on that connection. Or, do I just need to pull harder. Or, would it be easier to use a small pair of needle-nose pliers...or something of that nature.? Didn't wanna go there unless that is the proper way to do it. Don't wanna break the circuit card. Any further assistance appreciated. Thanx!

[Woodhacker]

I am still stuck with the top loose but not knowing how to unplug the wire as indicated in the PDF Bud sent me. I tried pulliong it with my fingers but it doesn't appear to want to come loose. Should I use a pair of hemostats or a small pair of long-nosed pliers to get it out?? I have taken bunches of computers apart and know that sometimes wiring going into a card will have a little clip on it that makes sure the wiring does not come loose. Is that the case here?? Not being able to carve is making me sad :sad: And, not knowing how to get those stupid wires loose is making me nuts!! :mad: Any and all help deeply appreciated.

[PCW]

Richard

If you are referring to the plastic clip connectors they have a little adhesive to prevent them from coming off unintentionally. Just take a pocket knife and score the line and they should pry apart.