Homemade Epilog rotary

[David McHenry]

I had a guy build me a rotary for my Epilog 40 watts and after 6 months and getting ripped off I finally received it. Here's my problem. Besides the crappy design the scale is not correct. The reason I wanted a custom rotary is that I want one with a chuck and I do not have the time to build it myself.

When I tested this I used a .5 in dowel and set the page to 1.57 (D x pie). My first run on when about 40% around the dowel. By increasing the page vertical setting I also most got it to burn completly around the dowel but the pages seting was at 4.5 inches to burn around a .5 dowel.

Heres what I know. The rotary is using a vexta stepper P/N:PK266-02A. This stepper is 1.8 deg but Epilog uses a .9 deg step. Also I did not count the teeth on the gears but the gear on the stepper is very small and the gear on the shaft of the chuck is very large. So large that the laser head will hit it if I'm not careful. Another issue it that the motor is mounted so close to the chuck the if I open the jaws any larger than .5 inches the back og the jaws hit the motor.

I'm thinking of changing the stepper motor to Epilogs model with the .9 deg step, changing the gears and relocating the motor further away. Basically I need to completely redesign this thing.

My question is do I need to go to a .9 stepper and does any one have the size of the gears or the radio. I read somewhere that it was 6 to 1 but if someone has one to measure I'd fell better about buying them. I'm already out quite a bit of money. . I'll upload some pics later tonight so you guys can see what I have.

Thanks

Dave

[Dan Hintz]

I would think the cheapest method is to replace part of the gear train for an extra divide-by-2...

[Gary Hair]

Dave,
I think you could use the stepper that came with it if you change the gear ratio. Sorry that I don't know what it would be, but it must be possible, no use change the stepper and the gears.

Gary

edit: apparently Dan and I were typing at the same time, he was just a bit quicker than I was...

[George D Gabert]

Just food for thought.

I do not know much about the Epilog print driver, but most print drivers have a multiplier/calibration from actual dimension to print dimension. Change the default until you get the vertical units to match the full diameter you are looking for when using your rotary.

GDG

[Joe Hillmann]

Can the epilog print driver be used to drive a rotary with a chuck? I assume since in the epilog rotary the part just sits on the rollers and if the rollers turn one inch the part will turn one inch it doesn't have a spot in the driver to program for the diameter of the object, and also that it will be spinning in the wrong direction. Whereas with a rotary with a chuck you program it for every item based on its diameter so the print driver can then figure out degrees into inches.


Trying to explain this a little better.

With the epilog it looks like one inch equals about 57 degrees no matter what the diameter of the work piece is because the degrees per inch is biased on the diameter of the drive wheels.

With a universal rotary (with a chuck) one inch on a one inch diameter work piece is about 114 degrees and one inch on a 3 inch piece is about 38 degrees and the print driver has to be able to figure that out.

Although you could get around that by making it the size you want it then stretching it what ever percentage of 2 inches that your work piece is and then mirror it up and down. It would look very messed up on screen but would come out correct on the part. (that is assuming the epilog print driver doesn't ask what the diameter of the part is)

[Glen Monaghan]

I'm amazed you ever got anything from him!

You can either change the gearing or change the stepper if you want to match the Epilog rotary, but realize that you'll have to scale designs according to the engraved item's diameter/circumference with a chuck, unlike with a roller design.

FWIW, it is common to overdrive steppers, often 2x to 3x. However, that stepper is rated 5V and Epilog's drivers are 48V without current modulation. So, you are overdriving the motor almost 10x and undoubtedly maxing out the driver's ability to supply current and generating a lot of heat and stress...

-Glen

[Leon Sandstrom]

Just curious...where would a chuck type drive be better? Are you trying to engrave bowls turned on a lathe where they won't sit on the rollers without sliding? Seems to me a chuck would just get in the way unless the piece was bigger diameter than the chuck itself. What are you wanting to engrave exactly? You really got me thinking about the uses for a chuck system, but the only thing I can think of is big diameter bowls with a shallow depth.

Leon

[David McHenry]

Glen,
I kind of figured the stepper was rated to small for an Epilog. I'm going to see about replacing it because of the voltage rating. I dont know how common a 48 v is but I'll be starting a search tomorrow. I got the gears off tonight and broke the larger one. Looks like Bill didn't want it taken apart. My check is also stuck. The threads were loose on the chuch and there is not backing plate so if you tighten it up it jams up agains the mount. For the gear ratio I glued a nail to the end of the stepper motor and began the exciting process of counting how many times it turns. Here is what I found.
1.5 turns = 1 inch
3 turns= 2 inches
6 turns= 4 inches
6.75 turns = 4.5 inches
and I think 1 turns = .75 inch if i wrote it down correctly.

The gear on the stepper was 20 and the one on the chuck was 130. I think that 1 to 6.5 but I'll never know because I broke the gear. Stepper motor shaft was bent when I received it also. I wrote down the wiring and took picture but its to late to post. I think the only reason Bill sent me the rotary is because I got him 3K for making an item for my company in which he only delivered half and the work was shotty. For the chuck I want it to egrave around pens and such but mostly for doing some inlay on pens. I'm in the for $500 so I'll throw so more money at it and get it to work. What get me is that is was farily easy for me to get the gear ratio. Bill must has used just any gear laying around his shop to put on the rotary. Sad thing is that is does work even if the motor and gear ratios are wrong.

[David McHenry]

Sorry about the spelling in the above post.......time for bed

[Leon Sandstrom]

If for inlay on pens, then the only solution outside of the manual step is to have like blanks for the different type of wood and cutting the pieces separate. It is possible. Easy with CNC machine. If just relying on engraver, your lathe work better be good. You don't need a chuck to do this, just Martel much the same as you would use on the lathe to sit in the regular rotary made by Epilog. Again though, the closer you are to like blanks, the better. The problem is the angles created based on the diameter of each separate wood being cut. I see another patent coming soon if you figure it out. Of course now a days you can patent an idea before it actually works. Those with money do it all the time. Haven't looked, but probably already done. Always wondered how engraving cigars could be a patent. Anyone can do it but can't sell online without paying the first guy to do it because he patent the idea. Not fair in my eyes. Then again maybe I just read it wrong. For that matter, if you engrave on a leaf I think they can come after you for money.

[Glen Monaghan]

For the gear ratio I glued a nail to the end of the stepper motor and began the exciting process of counting how many times it turns. Here is what I found.
1.5 turns = 1 inch
3 turns= 2 inches
6 turns= 4 inches
6.75 turns = 4.5 inches
and I think 1 turns = .75 inch if i wrote it down correctly.


From what you've shown here, 1 turn = 2/3 inch (0.6666...) as in 3 turns/3 = 2 inches/3 or 1 turn = 2/3 inch

-Glen

[Leon Sandstrom]

Not trying to hijack the thread, just think this would work for pen inlays on the normal rotary. Have to admit am interested in seeing your chuck unit. Not enough smarts on my end to dive into a project like that.

[Joe Hillmann]

Glen,

1.5 turns = 1 inch
3 turns= 2 inches
6 turns= 4 inches
6.75 turns = 4.5 inches
and I think 1 turns = .75 inch if i wrote it down correctly.




All of these turns to inches is only accurate at a single diameter, Unless you are going backwards and actually mean inches in coral draw to turns of the chuck.

[Joe Hillmann]

Just curious...where would a chuck type drive be better? Are you trying to engrave bowls turned on a lathe where they won't sit on the rollers without sliding? Seems to me a chuck would just get in the way unless the piece was bigger diameter than the chuck itself. What are you wanting to engrave exactly? You really got me thinking about the uses for a chuck system, but the only thing I can think of is big diameter bowls with a shallow depth.

Leon

The chuck doesn't have any slippage so when you go back to 0 you run the same job a second time on the part and it will be in the exact same spot. You can also do items with handle or items that aren't round, you can do items with a large taper or items that can only be clamped on one end, you can do very narrow items such as rings or bracelets or the edges of a coin. You can advance it a set number of degrees or distance so you can line it up with something that is already on the part. About the only place that I have found it fall short so far is if I want to wrap a design around an object more than once.

[Leon Sandstrom]

Gotcha, I wasn't thinking out of the box. Can definetly see the advantages. Best of luck figuring it out. And when you do, I'd be interested in buying one. Never have to many toys.

[Chuck Stone]

About the only place that I have found it fall short so far is if I want to wrap a design around an object more than once.

It's more tricky, but you can do it right in the file itself.
You'll probably need to use lots of guides and multiple
layers.
And whenever you have success? SAVE THAT FILE!!
I've banged my head more than a few times when
I forgot that one..

[Michael Hunter]

There are lots of threads about home-made rotaries for Epilog machines, but none of them give the pinout for the connector in the machine.
Can anyone help on this please?

[Michael Hunter]

A further question : when the Epilog rotary is in use, is the dpi restricted to 300 and below?

Doing the sums on the wheel size, step angle and reduction gearing suggests this.

[Michael Hunter]

Surely someone can tell me the pinout for the Epilog rotary motor connector?

[Glen Monaghan]

Surely someone can tell me the pinout for the Epilog rotary motor connector?
How did you know I was surly, have we met before? <grumble, growl>

The rotary's connector shell on the bulkhead has no insert in position 8 which, if you look straight into the shell with the latch down, is on the same side as the latch and to the latch's right. Above that is position 4. On the other side of the latch from 8, is 5, and 1 is directly above 5. 1, 2, 5, 6 are the motor coils, 4 is the motor commons (joined), and 3 and 7 need to be shorted together to tell the controller when powering up that a rotary unit is attached (only connect/disconnect the rotary with power off!). Exactly how to connect the four motor coil leads goes to 1, 2, 5, and 6 depends on the motor and how your rotary is physically constructed.

-Glen

[Michael Hunter]

Thanks Glen - that is clearly explained and exactly what I needed to know.

Since I can only find a "similar" stepper motor at a sane price, I'm intending to use the machine signals simply as controls - buffering them with high power MosFets to drive the motor from a separate power supply. This way, I don't risk damaging anything Epilog.

A long-term project though. Apart from buying the motor (whilst they are cheap on ebay) I'm not in a rush, as I only get asked to do round things about once every 18 months.

[David McHenry]

All of these turns to inches is only accurate at a single diameter, Unless you are going backwards and actually mean inches in coral draw to turns of the chuck.
yes according to corell draw. If I set the page to 1 inch the chuck turns 1.5 times. 3/4 inch page turns it one revolution.

[Martin Boekers]

You may want to consider an indexer like this.

www.epiloglaser.com/cs_kallenshaan.htm (http://www.epiloglaser.com/cs_kallenshaan.htm)

I figured with a super blank cutter (Penn States Inds) it would keep diameters the same
without using a micrometer.

Also I though maybe waterslide decals would be cool with a CA coat for protection.
I enjoy turning pens and have lots of ideas.......just no time :(

[David McHenry]

I dont think you need to go that far. My motor is directly wired to my Epilog and it works fine. I think its 6 volt running on 24 or 48 supplied by the laser but I have not used it enough for the motor to get hot. I was going to put some resisters inline for a voltage drop but its seems to work just fine. Now that I got a brass insert stuck on the shart of the rotary I dead in the water for now. I may and try change the gears to get 4 inches in corell to 360 degrees on the rotary. I also wrote down how my motor is wired to the plug (wire color to pin) if someone want it i'll post it.

[David McHenry]

I forgot the I post the pics of my rotary under another heading. Search for my post ( not many of them) and you can take a look at it. I have some friends that work in a metal shop hepling me on a different design so if you can think of some improvememt let me know.

[David McHenry]

Heres my pinout to a single stepper motor NOT using an Epilog rotory.

[David McHenry]

I saw the same post and I talked to Ken for awhile. He gave me some hints to help me along. Couldn't tell me too much because its his bread and butter

[Joe Hillmann]

I dont think you need to go that far. My motor is directly wired to my Epilog and it works fine. I think its 6 volt running on 24 or 48 supplied by the laser but I have not used it enough for the motor to get hot. I was going to put some resisters inline for a voltage drop but its seems to work just fine. Now that I got a brass insert stuck on the shart of the rotary I dead in the water for now. I may and try change the gears to get 4 inches in corell to 360 degrees on the rotary. I also wrote down how my motor is wired to the plug (wire color to pin) if someone want it i'll post it.


Instead of changing the gearing to 4 inches/ revolution I would suggest figuring out what the diameter of your most common parts are and multiplying that by pi and setting that or close to that as one rotation that way you will have less stretching the y axis in corelDRAW.

as an example if most of the items you do are 2 inches across you should set the rotary to 6inches per rotation, if most of your items are three inches across then you should go 9 inches per rotation. That way you are doing less stretching so your PPI or lines per inch on the fourth axis (rotation) will stay close to constant with what it would be on the y axis if you didn't have the rotary attached.

[Cindy Rhoades]

I have the same rotary as you and I used it to run 500 christmas balls, some little bottle neck gourds and various other things that can be held with the chuck but are to light for the epilog rotary to turn. I will have to pay atttention to how I actually set up the artwork because when I got it to my satisfaction I just ran it. I guess I was happy to get mine that I didn't reallly pay attention to how I got it to work. I will tell you I bought a micro chuck to use and had a small extension made so that the chuck did not hit the motor. I have never used the chuck that came with it. It will get me by for right now until I can get another rotary from Epilog.