Engraving Head?

[CHodges@svm-us.com]

Does anyone know where (or if) I can buy a real engraving head for a PC router?

We need to engrave in 1/16" TwoPlex, and the depth of cut is extremely critical.

Thanks!

[jay]

Charlie, laugh if you will, but I had an engraving job I had to get out on short notice. All I did was to tie-wrap a Dremel beside and lower than my PC, purchased a Dremel vee-bit and got the job out in jig time with good quality. You also can purchase an adapter for the PC so that you can use 1/8" dia shank bits.

For small bits you might try www.thinktin.com (http://www.thinktin.com) or http://www.robbjack.com/index.html

[CHodges@svm-us.com]

Very clever!

What I had in mind is a cutting head that has a "shoe" face that is made of very slick material that will ride on the surface of the TwoPlex and ensure that the cutter penetrates exactly the depth needed - even if my table top is not perfectly flat everywhere. The shoe and the tip of the bit are a fixed distance apart, and they both float up and down in unison as needed in a spring-loaded mechanism.

Is something like this available for me to use on a ShopBot?

Thanks!

[billp]

Charlie,
It really might be easier to just do a good levelling job on your table and follow Jay's example....Some of us regularly cut lithophanes with tolerances much smaller than you are going to use for your letters. With a flat table you can get VERY tight tolerances for thickness..

[CHodges@svm-us.com]

Thanks!

Maybe I just don't understand, but the engraving machinery I am familiar with has a machined aluminum top, and the TwoPlex is stuck to this top with double-faced masking tape because the plastic tends to buckle with lateral force.

Without an engraving head, the cutters would sometimes completely pierce the under-side layer or not cut through the different-colored upper-side layer.

Please forgive my ignorance about ShopBots (I don't own one yet), but are you saying this type work can be done successfully WITHOUT an engraving head?

Thanks again!

[ron brown]

Uh, Charlie,

Yes, when you get the machinery tuned, amazing things can be done. I have cut the multi-layered stuff with one of the older ShopBots. I'd bet the machine has fewer limitations than your mind and your education.

Ron

[grandpaspastime]

The commercial and jewelers engraving machines use a nose cone to glide over the surface and the cutter bit is extended thru the cone via a threaded adjustment, Thus the fixed depth. None of the commercial machines have a spring loaded cutter. the nose cone arm is usually controlled by hand pressure or in the case of United Inovations cnc engraver the entire cutting head is pressured by tension in the cutting direction. You could call united Inovations and see what their cutting unit costs and if it could be mounted on this z drive axis. the united inovations cnc engraver cost is around $18,000.00 or it was a couple of years ago when I sold mine. The other major manufacturer is Hermes and they have a cnc unit as well.

[papadaveinwy]

Dale is right, some where back in the archives we had a talk on just this subject and one guy had a great setup. He mounted a head from an old manual engraver next to his router with a motor to run the spindel head via a small o-ring type belt then he could do very detailed engravings including some slightly curved pieces as the cone Dale is talking about will follow the irregularities or the very slight curve. When I had my Bot I had ordered it with two z's and I mounted a head and motor from a sherline lathe on the second one thus I could machine metals etc a lot easier than with the router slowed way down, The sherline is variable from 0-2800 RPM David in Wyoming