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DumbDawg
05-24-2012, 03:43 PM
Yes I have read thru the threads, tried a few suggestions and seems the problem is getting worse.

The machine is a "C", replaced sensor board last year, and it has 144 hrs of up time...

When I put a 1x6 in for a small project it goes thru all the usual, load this, measure than, homing but when it goes to the final, measuring board thickness, it comes up as Z axis stall. When I put in a piece of wood larger than 6 inches it goes thru fine and carves out the pattern... that is until this morning... It did one carve but when I flipped the piece over for the other side carve it failed...

Did sensor checks and the Z axis was different each time, as follows...

Z axis - 1st run = 49.32, 2nd = 48.44, 3rd = 48.29
X axis = 105.02
y axis = 62.44
These were with the tests... before the test the Y = .007, Z = .012, X = -143.281 Board sensor = 0, board track = 1.370

Any ideas?? Thx

brian

Digitalwoodshop
05-24-2012, 08:25 PM
Encoder Clear Disk spinning on the Z Shaft.

Encoder is dirty.

FSC Cable is BAD.

Z Motor is Bad.

Controller is Bad.

Z Roller Bearing is Frozen.

Z Belt loose in the back.

Z Motor Screws are loose either the motor to the gear box accessed through the inside of the Gearbox OR the Screws holding the gearbox and Motor to the machine are loose.

If I were a betting man... Bad FSC Cable...

AL

DumbDawg
05-25-2012, 11:43 AM
Thx Al

The truck moves freely by hand, to the extreme ranges both horizontal and vertical, the travel doesn't stick or pause anywhere and seems smooth. Belts feel tight and there doesn't seem to be any teeth missing. I've pushed, pulled and tried to wiggle anything that might look like it could come loose and everything seems tight. I checked both ends of the cable and its clipped in securely. I have a dust collector hood I built into it and I blow the whole thing out after finishing a project as I know just how stupidly finicky this machine is to dust, heat and vibrations. Funny thing about the dust collector hood is that I can NOT do a menu setup with it in... I have to go thru all the menu options with it out then start the carve. When the machine starts to carve I have to pause it, install the hood, then continue the carve... its the only way it will work...

Anyway Thx for the heads up... guess I'll start by ordering a cable...

brian

bergerud
05-25-2012, 11:56 AM
The behavior of your machine with both the z axis stall and the dust collector - menu problem sound very strange. Maybe there is a connection. Could you explain in more detail about the dust collector menu problem?

chief2007
05-25-2012, 12:32 PM
Check the depth of the wood you have loaded in your project. Double check the thickness of your wood as well.

DumbDawg
05-25-2012, 01:55 PM
Hi bergerud

The problem regarding the dust collector and menu system is an odd one... I built the dust collector hood and it sits on the truck side like others do... There is enough clearance that the spindle doesn't meet the hood anywhere and it rides about 1/2 inch off the surface of the carve piece. My guess is that it makes it to dark and the sensors don't read properly... your guess is as good as mine..

I can put a piece of wood into the machine, lower head yada yada yada... Pick the project, and I usually know which bit it will carve with so I load it at the start... When the machine goes to find the bit it goes thru the stages then centers itself and says load bit... Press ok several times at prompts... it does its thing then centers again and says load bit... repeats endlessly... As soon as I remove the hood it does its checks, homes and starts carving... At that point I pause it, load in the dust head and then start the carve. I've tried to get it to carve with it loaded but it won't period so I just work around it... Its not a problem with the menu but merely a problem during the menu options setup process in that the machine will NOT proceed, for some unknown reason, while the dust hood is in place... Its a quirky machine at best...

Hope this clears this up... I'm pretty certain the Z axis stall has nothing to do with the dust hood because the dust hood can not be in place when the machine is finding the board thickness or any of the other sensor operations etc...

Thx anyway...

DumbDawg
05-25-2012, 02:00 PM
Check the depth of the wood you have loaded in your project. Double check the thickness of your wood as well.

Its the same wood I've been using all along... 1x6, 1x8's and 1x12's... so in reality they are 3/4 planed lumber... thickness isn't an issue.... Plus these are patterns/ projects that I have cut out earlier, nothings changed... I even reformatted the memory card, refreshed projects, checked them in Designer to make sure no changes were made.... to no avail... I'm thinking Al's on the right track... yet another parts failure in a quirky machine...

bergerud
05-25-2012, 03:41 PM
Hi DumbDawg,

The two problems could be related. The z stall and the wrong bit error can both be caused by the computer somehow getting the bit length wrong. How this could be related to the dust collector, may be a clue. I am sure it is something in Al's list. I will bet that when you do find the defective part and replace it, both problems get solved.

fwharris
05-25-2012, 04:16 PM
With your dust collector in does the bit plate come out all of the way and does the bit go down 2 times to touch the bit plate????

DumbDawg
05-25-2012, 08:43 PM
I'm pretty sure the problem is in the cable and has nothing to do with the dust hood. The hood thing has always been this way, as in if its in the machine then the machine won't go thru the sensor readings and onto carving. I have always had to leave the hood out until the machine actually started to carve. Then I'd have to stop it and put the hood in place, then continue the carve... Which it would then carve the project without any further troubles... If I have to change bits, say to route out the project, then I'd have to repeat the process each time... No big deal...

Its the other problem with the cable and z axis stall which crept in thats the cruncher now. It was fine for a carve, then it wouldn't accept 1x6 boards... No problem, I switched to 1x8's... then it decided against, on accepting 1x8's half way thru a second carve... now it does nothing.... oh well... back to twiddling the thumbs waiting for parts.... seems to be a regular event with this machine...

bergerud
05-25-2012, 09:21 PM
Sorry but I am really curious about your dust collector mystery. Is it metal? Does it screw up the machine if it just touches. Is it grounded? Does it stress the casing of the machine? My thought was that something on your machine might be barely connected or some electronic part barely in working range.

Digitalwoodshop
05-25-2012, 10:23 PM
I am starting to wonder if the Board Sensor has a broken LED and with the Dust Collector OUT the ROOM LIGHT gets to the Board and REFLECTS... With the collector in, the light is blocked and hence a problem....

I just posted the Sensor stuff about the LED's Snapping Off and how to use Options and get the number on the LCD with White Paper... It could be a bad sensor.... OR... a BAD FSC Cable and the 6 inch Y Travel and the FSC Cable is Broke... Then the 8 inch... The FSC Cable is getting worse.... A broken wire touching less often.... The FSC Cable is a Consumable.... Needs to be replaced when damaged but will last YEARS if no sharp bends...

Check out the other post with pictures.

Good Luck,

AL

You can always email me or call for advice. But I would order a Board Sensor and a FSC Cable.... Don't forget about Cut Motor Brushes for 250 Cut Hours, the Y Gear Box Bearings, the X Drive Gear, and Roller Bearings and Screws.... SAVE on Shipping NOW by ordering together.. NOW.. Less Waiting later.... IF you can swing it...

DumbDawg
05-26-2012, 11:35 AM
Sorry but I am really curious about your dust collector mystery. Is it metal? Does it screw up the machine if it just touches. Is it grounded? Does it stress the casing of the machine? My thought was that something on your machine might be barely connected or some electronic part barely in working range.

:)... Its an oddity to be sure... The hood I built is wood, there is enough clearances for the spindle to not touch the hood when its in. The hood just sits in place on the top of the front rollers, that ledge thats there. Its held in place from moving forward or backwards by a clip that sits over the lip of that roller ledge. I have a 4inch sewer pipe thats fitted to the hood and it pokes out the hole I cut in the lid of the machine. The dust collector system connects to that by a foil flex hose and thats onto a 4 inch sewer piping to my dust collector... And I have cooper wire wrapping the foil and sewer piping, grounding the whole shebang.. I should get some pics if I can...

Its a baby sitting thing rather than a problem, for me... Its would be nice if I could get the machine to go thru the setup and carve with it in... but no big deal... Now... it would be nice if I could just get this thing to carve longer than just a few projects without breaking down... I'll try and post a few pics here if you want to see what I've done...

brian

DumbDawg
05-26-2012, 12:03 PM
Hi Al... thx for your input... unfortunately I'm not in a position for ordering a lot of parts... My physical condition due to accident has left me un-employable and this machine was supposed to help me keep my hands busy... It was a lot less frustrating flying rc helicopters than this machine is... So far its had more down time than running time... I have limited endurance before the pain drives me out of the shop, so when I have to try and coax this machine into actually doing anything just gets to be to much... This thing has been super sensitive to vibration, heat and dust... who'da thunk it would encounter any of these conditions???

I replaced the board sensor just last year with the new one, the one thats supposed to be more robust, glued... I have run a total of 5 projects on it since changing it out... 3 christmas wreaths and a couple small apples on a 1x6, and a small house number sign... Anyrate... I'll start with the cables and go from there... I'm seriously thinking of just getting it running and selling it... its been a money pit with little to show for what its produced... When it does work... works fine... but thats only when its actually working... Don't mean to rant but its to the point of frustration with this pos that I'd rather endure a 1000 paper cuts than try and baby this thing to work or spend more money into it... The heli's are looking better every day...

cheers

DumbDawg
05-26-2012, 02:54 PM
Going to try and post some pics here... Took them with my cell phone so quality isn't the greatest... Also these are right after the machine got thru half a carve before deciding to z axis my project to death... So you can see that the dust collection is pretty good. I haven't blown anything out with compressed air yet...

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bergerud
05-26-2012, 03:57 PM
Maybe you do have two separate problems. That dust collector looks very wide. Could it be as Floyd said, that the dust collector interferes with the swinging out of the bit plate? As for the z stall, maybe Al is right about the FFC wire. I notice you live here in Canada, so like me, you are on your own! You may have to get the machine out of the box and continue to trouble shoot. It may be that the FFC wire is just loose.

DumbDawg
05-26-2012, 08:04 PM
Maybe you do have two separate problems. That dust collector looks very wide. Could it be as Floyd said, that the dust collector interferes with the swinging out of the bit plate? As for the z stall, maybe Al is right about the FFC wire. I notice you live here in Canada, so like me, you are on your own! You may have to get the machine out of the box and continue to trouble shoot. It may be that the FFC wire is just loose.

I originally thought this to be the case so I had just placed the hood in and watched it while it went thru the finding bit. The plate and truck with the bit have the clearances needed and nothing rubs or prevents them from full movement... I couldn't figure out WHY it would find the bit, click click... touch the plate... then center itself and ask for a bit... then repeat itself for as long as I was willing to repeat the process... it wins... I remove the hood and it finds the bit then does the board check, homing etc... I originally thought it was maybe to dark in the unit and the sensors couldn't see properly but this shouldn't have any affect on finding the bit...

I think I'm going to have to dismantle the box, remove the machine and tear it down... doesn't appear to be any way around this... then try by guess'n by golly replacing parts until it clears up... If I do this I might just as well fabricate covers to cover up exposed circuitry and put sheathing over all the exposed wires... Maybe put in some LED's to light up the inside so the sensors can 'see' the wood inside the machine... Things that should have been done from the design stage... Time to modify and tweak I guess...

TerryT
05-26-2012, 08:52 PM
This is very interesting. Brings up some questions for me though. First, how does your machine know that the dust collector is in place? Something has to be touching, rubbing, displacing a loose wire or interfering in some manner that is preventing the machine from finding the bit. Second, isn't the board sensor IR? Ambient lighting should have little effect on it i would think.

DumbDawg
05-26-2012, 09:17 PM
This is very interesting. Brings up some questions for me though. First, how does your machine know that the dust collector is in place? Something has to be touching, rubbing, displacing a loose wire or interfering in some manner that is preventing the machine from finding the bit. Second, isn't the board sensor IR? Ambient lighting should have little effect on it i would think.

Well I have puzzled over this for many hours myself... and I am absolutely no closer to finding out than when it first started... The truck moves freely over to the bit plate, it does not rub or touch anything... It travels fully over to the far side, bit plate... the plate pops out, spindle lowers the bit, touches it, raises, does its click click, lowers and touches the plate then centers itself.... I have watched it do it probably two dozen times, min, to see if it touches anything... it doesn't... As for displacing a loose wire... it can't because all the wiring is on the other side of the machine, rear rollers... this just sits on top of the front rollers... Remove the hood and away it goes... its a poser...

Its an oddity to be sure but its not responsible for the z axis stall because once the carve begins I can pause the machine, place the hood in and it continues just fine... Also if the chuck were to hit or rub the hood when running I'd hear it right away, wouldn't be something you could miss... This happened to me when I first installed the hood last spring. I didn't have enough slack in the flex pipe and it lifted the front of the hood up by about a 1/2 inch. Enough so the chuck ran against the hood top, 1/8th ply, made lots of noise which I shut down immediately... Hasn't done this since putting a longer piece of hose onto the 4 inch pipe...

As for the board sensors I could light up the inside of the machine with IR LED's to see if finding the boards edges would make it easier for the sensors to see... Just going thru some ideas to take some of the frustration out of this thing.... I'm thinking that if I have to dismantle the thing I might as well try tweaking it some as well... I have a product called ShapeLock that I can use to make moulded covers to keep electronics from loading up with dust etc etc.. Sheathing costs next to nothing... I might even have the right ends for making wires for this machine and will just make my own... Still have lots of wire, connectors etc etc from flying rc heli's... I'm either going to get it working, just a matter of time...

fwharris
05-27-2012, 12:11 AM
Just brain storming now:

What bit is this happening with?

Does the bit plate stay in the horizontal position? Meaning there is no excessive flop or play in the bit plate when the bit touches it.

bergerud
05-27-2012, 02:02 AM
In my experience, I have never had a reasonable bit rejected on the first measurement. Only in extreme case of the bit too short (or bit plate stuck in) or when the bit is measured as different for the second time in a multi-bit project. Therefore, I think the bit rejection must be an electronic data problem. Since it is somehow related to the dust hood, I would check the z encoder. Is the encoder cover loose? Does it hit the machine cover or cut motor wires during the bit plate check? The dust hood and pipe could be flexing the machine cover. Is the machine cover loose?

After thinking about this for awhile, that's all I got. (I am back to thinking both problems are related.)

chief2007
05-27-2012, 08:46 AM
Have you tried just measuring a board, not through your project, but just using the measuring option to see if you get the Z stall?

If you measure you can measure your board, length, width, thickness with no problem, then this might give us another avenue to look at. If you get the Z stall, A few things come into mind - the FFC cable and/or a z motor problem, even maybe the circuit board.

Additionally the bit you are getting the stall from, does it have the pressed on adapter or is it the split collet, stop sleeve and bit?

DumbDawg
05-27-2012, 11:20 AM
@fwharris - The machine has only 144 hrs and change, running time on it. This bit thing happens with any of the bit I put in whether its the pressed on bits from CW or split collets... The bit plate seems to be solid and the whole thing does the exact process from start to finish only when the hood is in it can't find it when the hood is out it finds it with no problems and carries on... I would suspect if the plate was floppy or with to much play in it then that would translate into random 'can't find bit' whether the hood is in or out... no??

@Berg - I played with bit lengths thinking that same thing... On bits with the split collet I tried varying the lengths to see if that would do the trick... nope... additionally it also does the same with the CW pressed in bits... I'm inclined to go with the electronics problem as well as there just doesn't seem to be any reason for it to be mechanical... Its going to get dismantled today...

@chief - I haven't tried measuring a board just going thru options... Will try that this morning tho before I dismantle it...

Appreciate all the responses and help... many Thx....

brian

DumbDawg
05-27-2012, 06:58 PM
Well... went into the shop today to try a board measure test as suggested by chief... but I wanted to make sure I double double checked everything again just to make sure or reconfirm the problem of the z axis stall... I had a 12x24 inch piece of spruce shelving I had that was for a plaque I was going to carve for someone... Put that in, loaded the bit.... it found the bit, measured the board and carved the whole thing, 3 hrs, with no error... still scratch'n head... Tomorrow I'll try some smaller wood to see if the z axis pops up again... Maybe its a 'traveling' error in that its failing on smaller stuff and advancing to larger??

Digitalwoodshop
05-27-2012, 09:34 PM
Just another thought... We like to always keep the board under both rollers and flat to the sand paper belts.... When a short board is used, it can let the board pop out from under the roller and sometimes it will lift... And if the Z head is cutting and it pops up, it could cause a Z Stall... Just a Thought....

AL

SteveNelson46
05-27-2012, 10:38 PM
If you are still having problems, I would suggest disassembling the Y and the Z trucks all the way down to the bearings. Put a drop or two of 3 in 1 oil on each side of the bearings before reassembly. Carefully inspect all wiring for any checks, cracks, or breaks and if you can, do a continuity check on each wire. Yes I know this is a real pain in the neck and it may seem like a lot of work but, it shouldn't take more than a couple of hours. I did it when I was having random Y axis stalls and discovered that when I had replaced a board sensor earlier I didn't get all of the wires inside the plastic cover (working upside down with a mirror and a flashlight). There was a wire loop protruding from under the plastic sensor housing that was rubbing on the bottom Y rail and on one of the bearings. After reassembly, the problem went away. I'm not saying this is your problem but, dis-assembly inspecting all parts and wires and reassembly will eliminate most of the mechanical possibilities. It will also give you a lot of insight on how the machine was engineered.

fwharris
05-27-2012, 11:23 PM
I'm not saying this is your problem but, dis-assembly inspecting all parts and wires and reassembly will eliminate most of the mechanical possibilities. It will also give you a lot of insight on how the machine was engineered.

Amen to that! And we thought Rocket Science was way over our head! :D