Figured the NFA area might be a good place to post this question.  What are some quality manufacturers of engravers?  What is best for lower engraving work a milling or laser machine?  Which is the better laser CO2 or YAG?  How many watts needed for engraving lowers or uppers?  Thanks.

You would need a rotary engraving machine so that you can get the depth needed.  Most laser machines basically just bleach the coating.

If you want a laser that will cut to the proper depth you would need a YAG laser.  These are very expensive.

We have an older Hermes, found on CL, and got a new computer & the software from Gravograph to run it.  It does everything we need - rounds for suppressors, graphics, etc.

I can't speak highly enough of Gravograph's customer service - they are a wonderful company and have given us exceptional support over the years.

I've been using a TAIG 4th axis machine with great results.

I recall setting up a Gravograph when I worked a contractor position.  We didn't spend much time learning the machine however.  The last time I checked will one of the people I worked with they were not very fond of the machine and wish they never spend the money for it.

I believe you showed me this machine the last time I picked up a suppressor from you.  At the time you told me you were still learning to use it for engraving.  Good to hear it has been working out.  I believe you cut a baffle on it too.

Is your machine their CNC Mill and Micro Lathe combo?

New Hermes rotary pantograph engravers are good machines. They use removable plates on a tray and are quite simple to operate. I've used one for several years with only one screw up on a personal lower (I overlapped 2 letters in my name because I was too lazy to lock the letter plates in). In any case you should be able to get one for about $500-1000 used. The YAG lasers are well into the 5 digit price range for one powerful enough to engrave and not just mark.

Thanks for the info.  So is "marking" a lower not sufficient for NFA purposes?  The engraving must be a certain depth into the metal correct?

For NFA it must be .003" deep and letters must be at least 1/16" high.

Exactly. Most of the laser engravers will actually engrave on soft materials like plastics, wood, rubber, etc but will only mark metals. They get hot enough to pretty much scorch the surface but not actually remove material. Wood burns if you'll recall at about 500 deg while aluminum doesn’t even start to melt till 1200 and you'd actually need to boil it to engrave (somewhere about 4-5000 deg). Laser trophy shop engravers are pretty much just discoloring the surface and that's about it.

So laser engravers are pretty much out as far as NFA engraving of firearms.  Out of curiosity will a water jet get the job done?  Are there any benchtop water jet setups for engraving?

Out of curiosity - has anyone ever tried or heard of using a sandblaster, like they do for stone engraving?

Most laser engravers only etch the surface (they remove just enough material to leave a presence..such as removing the anodizing). It would be more cost effective to use a CNC rather than an expensive laser that actually engraves into the material to a certain depth (per ATF regs).

Water-jets...well..I think it would be hard to get the required depth without cutting through the material. And if your "water-jet engraving" a finished peice, it may remove the surrounding finish (such as anodizing).

Sand blasting wont get you to the required depth per ATF regulation.

I suppose you could use either a blaster or a water jet but I have no idea why you'd want to. Put it this way, using a rotary engraver (even a CNC one) will cost you maybe $2-4k if you buy brand new or $1500 or less used. They take about 5 min to set up, you get great depth control and all the clean up required is to blow the part off. With a water jet you're going to be into the machine probably 5 figures to have wet, abrasive shit EVERYWHERE and I honestly don't know how well you could control your depth. And yeah, you could use a sand blaster to do it with a solid template but you're going to have to lay into the metal for a bit to get the right depth and again, abrasive shit all over your customers nicely finished gun. Y'all are trying to reinvent the wheel here. There are generally 6 ways to engrave that are generally accepted in the firearms industry.

#1 Rotary engraver or CNC (cheap, easy, and efficient)
#2 Laser engraving (VERY expensive for the machine but works well)
#3 Roll marking (not practical for the little guy as the rolls are spendy)
#4 Electrochemical etching (takes practice and looks good once you get it down but only works on metals)
#5 Stamping with letter punches and a hammer
#6 Casting or forging into the rough part as it's being made

That's it. Pick one of those and run with it.

The 1/16" height requirement is for the serial number only. There is no height requirement for additional information such as the model (if any), caliber, manufacturer's name, city and state.

I ended up purchasing a used Bellco PM3 machine for $500ish off of Craigslist.

http://bellcoinc.com/engraving.htm

I have not had any issues and parts/cutters are a phone call away from the manufacturer.

I hear those are good machines. I've only used Hermes personally but I can't imagine they are too different as they pretty much do the same thing the same way. What are your opinions on it?