Engraving


Ok, some things are a whole lot more complicated than you would think.
Engraving for example. The irregularities in thickness of material can be a
real pain some times.
I found a guy to make me a spring loaded engraver, and that helped. The tip
he used would bend at the slightest hard lip of even a .002. Otherwise it
worked fine. Hills and valleys it dragged over just fine. I even used it
to engrave some sockets to see how much incline it would climb. (I could
make my own now that I have the lathe.)
I wanted a stronger harder engraving tip. I ordered some tungsten carbide
ones and some diamond ones. The diamond ones worked great even on chrome
and stainless. On aluminum of brass they gummed up. The tungsten ones
worked ok, but were just not sharp enough. I wanted a better line with less
pressure to reduce gouging.
Of course I was dealing with finding a good way to clamp down some small
brass plates at the same time. The brass plates came with adhesive tape on
the back so just clamping down the edges didn't work because it would warp
pretty badly around the tape. Fine if it were steel, but for brass that was
just too much. The engraver would gouge too deep.
Somewhere along this process I picked up a cheap mill vise hoping it would
help, but the bolt slots were stupidly large and it was too wide even if I
got longer bolts for my t-nuts and used washers.
Finally today it all came together. I drilled and counter sunk the flats on
the vise, grooved the jaws, and found a way to sharpen tungsten carbide drag
engraving tips on the cheap. I got a very sharp and well centered point
too. I never realized before how hard it is to drill cast iron by the way.
I drilled the bolt holes and then milled flat bottom counter sinks for the
heads on the vise.
Engraving tip sharpening setup.
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I know, I know. I need to keep all that dross blown off the lathe.
Actual Engraving Video
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Note the scale milled on the top of the vise? That really increased my
comfort level in zeroing the cutting head of the mill, and also in placing
each piece for engraving.
P.S. Previously for another application I had found where a dull rounded
drag engraving tip solved a totally different problem.
Reply to
Bob La Londe
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When I did some engraving on anodized AL, I used a carbide bit and coolant. The coolant isn't really so much for heat, but the lubrication and flushing it provides helps a lot.
Reply to
Pete C.
You might consider a vacuum setup for engraving. When I worked in plastics we would use vacuum to hold plastic sheets when using a router to bring them to size. They never moved a bit even while taking an aggressive bite with the router.
If for example you would get a 1/2" thick plate and drill 1/4 holes every half an inch edgewise, then you plug the edge holes (except for the last one where you hook up the vacuum line), and then drill .030 dia. holes in the face of the plate, that should hold down any flat stock for engraving with no problem.
Another way might be to use hot glue to fasten the plates to a thicker piece of stock. To remove, use a heat gun. You might need to rig some sort of clamping fixture to assure that the face of the plate is parallel with the anchor plate.
Sounds like you are having fun. Good luck,
Reply to
Roger Shoaf
For drag engraving I have not needed much of anything. When I used a spinning mill bit to engrave aluminum I found a constant stream of air seemed to help a lot.
Reply to
Bob La Londe
I have played with a vacuum plate and it worked ok, but I really need to break down and buy real vacuum pump to play with it more.
I did some commemorative coins earlier this year using epoxy and then popped them off by heating them with a torch. These brass plates already ahd adhesive tape on the back which made some methods impractical.
Reply to
Bob La Londe
Next time at your dentist, ask him for his old burrs. They use all shapes, diamond, carbide, HSS.
Reply to
Bill McKee
You've got a very interesting engraving setup, Bob. I recall seeing previous posts about geting the mini-mill set up, but I don't remember seeing any details regarding the actual CNC'd model you're using. Did you buy the mill with the CNC conversion, or rerofit the CNC?
Some pictures of the entire CNC setup would be appreciated, if you've got the time.
It's not a good practice to use compresed air to blow away swarf and chips from machines. The force of the air pressure forces small chips into places where they will result in problems and/or excessive wear. A couple of brushes and a clean shop rag are much better for cleanup, followed by some fresh oil on the precision parts.
Some aluminum foil or other throw-away covering temporarily placed over the precision parts of a lathe are good ways to prevent abrasive debris from getting on them.
Reply to
Wild_Bill
I bought it complete, but some fab was required to assemble. It was harder to get the software setup right initially than to setup the mill. It's a Taig 2019 with a Deep Groove controller. One of the things I want to do is make a router machine for larger "rough" projects. Now that I have setup one machine I can see some of the advantages and disadvantages of a mill vs a router machine. For most of what I do a router machine would have worked better, and a non cnc mill for milling and one off fabrication. The cnc actually gets in the way and slows me down sometimes.
I also want to upgrade the steppers on this rig and switch to a Gecko controller. Sadly there is only so much time in a life. LOL.
I think I posted one once with a holder I had made for my dial indicator to check the table. I can post another.
Reply to
Bob La Londe

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