Tom, look into 5V driven relay modules. They are not that expensive. Just make sure the current draw is within the specifications of the BOB

Tom,

If you want to build one, here is a sample schematic. I would recommend building and testing on a breadboard before actually putting one into production use. You will need to do some calculations to configure to your voltages.

Tom, for switching lights etc. Google dx.com for 5 volt relay opto board. I bought mine there, make sure you check if it's switching when pulled low or high, depending on your controller and if possible choose the board where you can manipulate the behaviour with jumpers. Mine has 8 channels, and costed 16 dollars I believe.

Make sure you check rating of relays.

Amazon in another place. Ebay also.

Make sure you get the ones with the jumper to change it from high/low so it is universal to the input and allows more flexibility.

That's what I said Pete :D

Sorry Fox. Missed that.

Thanks guys I'll take a closer look. Thats a cheaper route than buying the board from PMDX, plus if I decide to make it myself I might learn something.

Again thanks guys, Pete didn't mean to highjack your thread:)

Not a hijack when it is about the mate

Retrofitting a CNC mill at work. Needed some custom legend plates. I thought I would give it a try again. The one on the left, I had the spindle speed way to high (forgot to change it when setting the toolpath). It melted the black onto the white. I kind of like the wiper look it has so I will take it in and let them decide. Although I don't care for the dot. The other worked out as planned.

https://farm8.staticflickr.com/7526/...7b7c458f08.jpg
Legends

Are you using engraving plate?

Plastic engraving stock for rotary cutting.

I am finally able to play around with the machine since getting my shed completed (my year long project). That kind of put everything on hold. After cutting out the legends for the machine at work, I really needed a better way to hold the sheets. After much searching on the web, I found an old thread on Shopbot with someone using a wet-dry vac for vacuum. I thought this was intriguing. While I needed a small table and he was using it on a large area, the theory was sound. Basically you need to make sure that you have the same surface area and volume capacity that would allow for unrestricted flow when all the holes are uncovered. Where this differs from deep vac design is you have to have a large surface area to draw from and requires a little different thinking. I have holes at every crossing of the lines. So I made one out of some left over plywood I had laying around (not the best choice but hey, I didn't think it would work). So I finished the cutout and tested it. I have to say it is impressive. With such a low level of vacuum, I never thought it would work. Covering the surface area with material you are going to cut and then the rest with chipboard or cardstock you cannot move the workpiece. While this in not an efficient solution and I will eventually buy a deep vac pump and cut out a new table to run dedicated ports, this does work well enough for now for legend engraving.

https://farm4.staticflickr.com/3947/...ede57084_z.jpg
Vacuum table using wet dry vac

Cool stuff.

This forum is starting to suck a lot lately...:D

Well stated.

A few pictures to show how the shop vac table was cut out. The top left is the top half as viewed from the top. The top right is the inside chamber. I matched the supports to the bottom have to help from material movement from vacuum. The slots cover every hole. This is to maximize the surface area for the vacuum to work. For the 2.25" hose it needs a 0.75" x 5.1" rectangular opening inside. So 0.375" pocket in both the top and bottom. I had extra buna cord stock left from the cyclone build so I put an O-ring groove in to seal when screwed together rather than glue. This allows me to replace the top later if it is needed The bottom picture shows the bottom half. As I said before, from my understanding, the entire area needs to be covered to work properly with the shop vac. Not segmented off like deep vac. I did try a piece of Advantech on the top to see how well it would hold down. It held surprising well and was fairly hard to remove. Maybe some of you will try something different so I have included a link below.



Here is the link to the drawings if anyone is interested. Click Here. Hey, I like to share and pay-it-forward. That is what this forum is to me. So sharing my experiences and designs are the least I can do. :)

Thanks Pete.

Finally got my screenset done. It was a good time to finish it. The graphic design is the longest part but I wanted something formed around the way I work (not saying that is the correct way). I added a probing tab to house the different tasks that I use with the probe. I still need to finish some of the scripting but it is a lot closer to what I needed. Getting ready to cut some more plastic signs. Will post progress as it happens.

So the table works well. I covered off until the sheet would not move. This is how much I was able to leave open. And a pic of the cut.

https://farm9.staticflickr.com/8640/...a8c03b9b_z.jpg https://farm9.staticflickr.com/8631/...d768e303_z.jpg

Are you going to show it to us?

Sure. Pics or the the set file?

pics are fine.

Here they are. I had to change the dpi and index the images to create a small enough png file with a fairly clear image in the original 1910 x 967 pixel range. All of them are about 100kb so they should not take long to open. However, with that being said, they are not the crystal clear images on the screenset because of being indexed and the gloss round buttons are washed but it is better than the download time the 40Mb would have been. I started working on this about 6 months ago and never had time to finish. Being laid up with illness gave me the time to draw up the graphics. While it is still not totally complete with all the graphics and code it is fully capable of use for the machine in its current state. I still have several images to create to replace the images borrowed from Mach3 and Big-Tex. So I cannot take full credit for everything yet. For readers in the future, I have no idea how long I will keep this folder up so if the link doesn't work, I have deleted it. Click Here to see dropbox folder

I wish I was half as smart as most of you guys.

Darren,
If I was smart, I would apply myself but I don't instead I learn from trial and error. I am not the fastest but I tend not to forget. I went to school for electricity, not computers. Didn't even have one when I was in college until the last year so it was all new and self taught. Why, because I don't like to have to rely on someone else to fix or make my stuff. Anyone can do the same, it is just taking the first step that is the hardest. I like to say we are not born stupid but become that way if we so choose.

We all learn best in our own way. "Smart" has little to do with formal education, but more to do with being logical, interested, and motivated. If this forum has shown me anything, it is that there are smart people everywhere and in every walk of life. There are also more 'practical intelligence' in these forums than many 'smart people' groups I see elsewhere.

Well stated Jack.

Pete, your screenset is pretty cool. I can see how relocating some of the functions together can work for you. Nice job!

Well said, Gents.

Nice work on that. I know firsthand how long the graphics part takes.

I bet you do Gerry.

Gerry, I know you do and thanks for the compliment. You have a smooth and well organized screenset. A lot of people will attest to that.


I just found a classic programming mistake of rushing when you should be concentrating, this was on a function assigned to a button and it did not match the label. Was driving me insane why the spindle would not work properly. In the end, it was the idiot that was making the screenset.....me. Well it is not the first time, you would think I would have learned by now. Working on the final buttons to be made and scripts for the touch off and auto set the DROs. I used the AskTextQuestion function on most probe buttons to prompt if I want to use the last value or use a new one for most actions and update accordingly. I will update the pics on Dropbox as I can.

I have cut out several labels using the 'shop-vac table'. I am very pleased. I think I may have to pick up some MDF to make a better top now.

Changes uploaded

Mayan Haab I draw up. If anyone is interested, I will post the vectors later. 34" diameter cut out of 0.75" pine.

https://farm8.staticflickr.com/7548/...c233ac10_c.jpg
Glue up


https://farm8.staticflickr.com/7471/...ff63664f_c.jpg
Cutting


https://farm9.staticflickr.com/8621/...407b9bee_c.jpg
Cutout

Nice

Impressive as usual Pete, nice job!