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View Full Version : Adding Z data to the Run LCD Screen in the future.



Digitalwoodshop
09-24-2013, 12:08 PM
I would like to be able to monitor the Z Depth as I use my machine and it would be a really nice addition to add the data to the Run LCD Screen.

I use the machine to cut FRP plastic tags on a carrier sheet. From time to time the machine would come up slightly short leaving a skin on the bottom of the tag. Since I print on both sides, the skin fractures leaving a cracked edge. Keeping the machine clean and tuned makes a difference but I may go with a smaller bit that the 1/16th end mill in the future. I use 1/4 inch strips of double stick tape to hold the loose tags in place as I do not use tabs that would fracture. I stop the machine now and pop out the first tag to make sure it is OK.

I will be doing a Vacuum Sled for this project.

I had thought of adding a Digital Readout to the Z like used in a Wood Planer but I though I would ask here first....

I have bid on a Tag Project that would require cutting 200 Sheets of Tags if we do them in plastic. I sent Aluminum samples yesterday but this Industrial Use of my tags could be huge... This is a $38.4 Thousand Dollar Quote.. :shock:

This addition to the LCD would let me monitor the depth as it cuts.

Just had a after thought... Since the Encoder already makes the pulses as an electronic guy I could tap into the pulse train or since I have old motors and encoders piggy back a 2nd encoder on the back of the Z... and use that to monitor the Z.... Or even add just a encoder sensor to the other side of the first disk... :)

I wish that talking module for the CW had taken off...

AL

bergerud
09-24-2013, 12:53 PM
That sounds good but I doubt it would help. The readout could only show what the machine thinks the depth is, not the actual depth. You need the actual depth. If the machine knew the actual depth, you would not have the problem you have!

How about this: Have the sled (or tape) be a different color than the tags so you can see the skin as it happens and then adjust by tweaking the head crank.

RMarkey
09-24-2013, 01:35 PM
To tap into the z encoders, you would need a data acquisition system as well as the quadrature decoding algorithm we use.

I would set the project depth a little thicker, and set the tab height taller, to make sure you clear the bottom.

mtylerfl
09-24-2013, 02:55 PM
...

I would set the project depth a little thicker, and set the tab height taller, to make sure you clear the bottom.

...except there are no tabs being used for his tags...instead, he uses double-stick tape to hold the parts in place. Would setting the project depth thicker than the actual material really yield a better cut-through? Now you have me curious how that would work!

unitedcases
09-24-2013, 08:58 PM
Could peg board be used at all in this application?

Digitalwoodshop
09-24-2013, 09:16 PM
Thank you everyone including Metallus for the input. Correct no tabs but the answer is to set the depth just a little deeper to solve the skin problem.

Further thought on the encoder is really a pipe dream and a digital readout is not really necessary.... If you search cut out letters made from MDF on eBay in the US and Europe you will find a booming business in unfinished MDF letters and words. Wedding Planers use the Mr. and Mrs. with names as part of the package. Plus common phrases in 12 inch high letters. You could use tabs but I was thinking of leaving a skin on the bottom to hold it all together then running it through my thickness sander to release the letters. They do connected letters that could be made by typing the text then laying zero carve region boxes on the connect then use the outline tool to give you connected letters. That was the reason for the first interested on the Z Depth...


So the plan for the Vacuum Sled was to use a replaceable hardboard top for each tag design. It would have holes drilled into the tag area to let the vacuum in from the bottom. I would make one for each tag design. Then I was reading on the CNC thread on Sawmill Creek a easier way.... They use Fiber Board and the vacuum is able to pass through the pores in the sheet. They seal the edges with watered down glue. So I could do a Artwork layout for tags then just cut the fiberboard with the normal tag cut out but use a 1/4 inch bit and make it 1/4 inch deep. Then use the glue trick to seal the 1/4 inch slots and sides of the fiber board. I have the mushroom plugs used on screw holes that would raise the fiber board off the carrier sheet placed by drilling 3/8 inch holes in the carrier and sealing the sides of the carrier and making it the vacuum chamber with a replaceable fiber top. In theory the tag being cut on top of the fiber would hold in place.... A Vacuum Switch I have wired into the Left cover switch wiring should prevent problems if I lost vacuum and stop the machine...


With the samples I made of Aluminum could be the final choice... time will tell... If I even get the project... They currently use Cow Ear Tags... My tag system will have the number plus all the details about the location... A PLUS.... The metal could be a $72K project... and he has buddies in other plants...


Keeping my fingers crossed....


AL

mtylerfl
09-25-2013, 09:59 AM
Of course...set the manually assigned bit-cut depth deeper. I thought Metallus meant to set the project (board thickness) deeper. Puzzled how that would possibly work.

We saw several vac-holdown setups at the CNC Jamboree last weekend. Interesting presentations - Randy Johnson did demos of a small-format vac hold-down box on his desktop Bot (a box about 8x10 -ish). The general idea could be modified for the CW with a little thought and effort put into it. Randy also showed an inexpensive vacuum pump purchased at Harbor Freight (spits a little oil when running, but it holds up well). For one of his demos, he was using a small "shop vac" that was purchased for about $29 as I recall. Cheap enough to throw out when the motor finally gives out. How long it lasts depends on how much it's used...I think Randy said to expect about a year or so before it needs replacing.

liquidguitars
09-25-2013, 10:29 AM
Would setting the project depth thicker than the actual material really yield a better cut-through? The answer is yes if your talking about the router bit going through the board normally a bit should go about 3/32 past the overall thickness of the stock.

In my case I set the board to .82" the max z depth for raster's and then hope the bit will cut through.

DickB
09-25-2013, 12:07 PM
I often set the project board to slightly thicker than my actual board to get clean cutouts when using a sled. It does of course cut into the sled a bit more, but that has not been an issue. Sometimes the board itself is a little thicker than nominal, and sometimes it is a little warped. Both can lead to incomplete cut through. Setting the project board a bit thicker solves the problem.