Sammy - The Story Of A Little Engraver

[epineh]

As the title suggests this is the retrofit log of a small engraver, here are the before photo's...he was already named Sammy by the previous owner (as you may notice) and if you go by maritime law you should never re-name a boat as it is bad luck, same applies here

[epineh]

I have a build plan for Sammy, use what I have available, and not spend a cent - I make no apologies for this, I will re-use anything I can from old parts and what I have in my shed to get the job done. Luckily I have some nice parts lying around

Any Hoo, here is the old controller, it looks like it had a keyboard and video interface originally and some serious electronics, but judging from the dust this may not work anymore...I may need more contact cleaner

The top view shows some inner workings, there are existing limits I will use if I can, as well as the stepper wiring and connection to the control cabinet, as it is all done and no real need to change anything.

[epineh]

Here are some closeups of the front and rear, I will use the LED on the front for power indication and the plugs and sockets at the rear for power input and possibly power to the new VFD running the spindle...also I have an old transformer lying around that outputs either 28 or 30 VAC that should be perfect to power the Gecko G251's I have in mind.

[epineh]

Here is the old spindle motor, this had a long and involved belt drive system, also the spindle itself was missing, wont be using this

[epineh]

Here is a pic of the front panel, I have changed the old red LED for a new green LED, which is a vast improvement in my opinion sorry for the blurry photo's, sometimes I have a beer while taking photo's...

Also a pic of the gutted control box with some newer hardware installed...

[epineh]

Here is the VFD that will drive the spindle, lying around the shed of course !
This is actually the VFD I have to run my new router that I am building, for now it can stay on Sammy until I have built the next router, the way I build things I have at least two good years before it is a problem !

The spindle itself is an Italian built beast, 150 Watt, er11 collet chuck three phase 240 volt, the VFD is a 240 single phase to 240 three phase type, perfect !

[epineh]

Alright, here is the electronics finished (mostly) and powered up, also the spindle mounted, this is how the machine is right now, all I need to do is to connect the limits as mentioned earlier. If anybody has noticed I haven't used a BOB on this build, but have chosen to take the connections directly to the Gecko's, this is all fine and dandy but I still need to have an estop and three limits/homing switches, also possibly a zero tool setter...

[epineh]

Well the best way I can see to add the limits/homing switches is to make a little PCB that I can add to make life easier, if only I had some way to do this...lol

Nothing could be a better test for Sammy than to make himself this PCB, after some mucking around, I found an old heatsink (yes in the shed !) that fits surprisingly well where the old job mounting assembly was, I got my mate to skim a little off the top and bottom to make a flat surface that sat onto the machined surface on the bottom of the work area and also a flat surface to stick the PCB's to be machined onto on the top. With a little time and effort I can see this being transformed to a vacuum table sometime in the future.

Here is the all important video of the PCB being milled

YouTube - Sammy Milling PCB

[epineh]

Here is a pic of the finished product...unfortunately I thought of the tool setter a little too late and only have inputs for three limits/homing and one estop, I could probably ditch a limit or double it up, I don't like the idea of no estop, or I could just mill another tiny PCB just for the tool setter, sounds like a plan

That is it for now, I will do some more in a weeks time to finish the build, pretty happy with the results so far, the PCB is neat and tidy, and should work without a hitch.

Russell.

[Tweakie]

Excellent BuildLog, thanks for sharing the information, very nice machine.

Tweakie.

[RomanLini]

Sammy is cool. And probably pretty old based on the original stepper drivers which look to be 4 FET unipolars with 2-transistor constant current supplies (on the heatsinks). And would have almost certainly been full step drive (yech!).

Anyway congrats on the rebuild, he's a good machine. He would also be good as a rotary engraver with that vertical height!

Are you going to engrave a nice new "Sammy" name plate? "Sammy II" perhaps?

[epineh]

Originally Posted by Tweakie Excellent BuildLog, thanks for sharing the information, very nice machine. Tweakie.

Cheers Tweakie

Originally Posted by RomanLini Sammy is cool. And probably pretty old based on the original stepper drivers which look to be 4 FET unipolars with 2-transistor constant current supplies (on the heatsinks). And would have almost certainly been full step drive (yech!). Anyway congrats on the rebuild, he's a good machine. He would also be good as a rotary engraver with that vertical height! Are you going to engrave a nice new "Sammy" name plate? "Sammy II" perhaps?

Hi Roman, yes the old drivers were most likely fullstep, I thought of firing them up to see what happened but decided to just go and replace the lot.

There is actually a rotary axis that came with the machine, I don't know exactly what I should do with it, the reason I have sammy is so I can make PCB's and not have to drill them out, which is really awesome, especially watching all the drill holes being done - so much better than me sitting on a drill press for half an hour !

My original thought was to use the rotary axis to flip a double sided board over to allow for machining both sides with one setup, still thinking about that one, add a toolchanger and that would be one sweet setup.

Funny you mention making a new name plate, I certainly intend to do so, I just need to find the right material, I could use that plastic stuff, or maybe a small piece of timber with some nice V-carving might be the go.

With a bit of luck I will retrofit a second machine before the BBQ very similar to Sammy but with a bigger cutting area, that is the machine that I will use Linisteppers on. I will use Sammy to make the boards for that machine.

Cheers.

Russell.