Diamond Drag vs Engraving Cutters on CNC Router??

[Tony Joyce]

Please keep it to CNC router based information, Thanks. I'm just trying to find out capabilities for use with what I have. I'm not looking for more equipment
Pros?
Cons?
Opinions welcome
First hand experiences appreciated.
Examples?

Thanks, Tony

[Jerome Stanek]

I use both it depends on the material and the look I want.

[Mark Bolton]

Please keep it to CNC router based information, Thanks. I'm just trying to find out capabilities for use with what I have. I'm not looking for more equipment
Pros?
Cons?
Opinions welcome
First hand experiences appreciated.
Examples?

Thanks, Tony

We have tried both and for us the answer really depends on your specific application. The issue with an engraving cutter if your trying to do very fine/precise engraving is that several factors will play into your end result. Machine/spindle runout, machine accuracty/rigidity, how precise your part/model/toolpath is, rigidity of your work holding, and so on. All of it gets harder and harder the finer and smaller and shallower you go.

With a rotating engraving tool your toolpath sets a specific cut depth and if your part varies much at all in thickness, flatness, or if your working on a part that is 3D and your model doesnt perfectly match the toolpath, you wind up with variations in line weight/cut depth and so on.

With the diamond drag your tool is spring loaded so very small variations in the material effect the spring tension much much less (pretty much imperceptible). But with the diamond drag you have the issue that you are not really cutting but rather displacing material which may or maynot be acceptable in your part. You can get slight raised edges around the engraving where the displaced material mushrooms up the edge of the engraving.

I think a lot of it is somewhat application specific with regards to which end result fits your part.

[Tony Joyce]

I should have been a little more specific. What I'm mainly thinking about at present doing brass with some lettering, maybe some scroll line art. Probably 3/8" - 1/2" in height on the lettering. Nothing to small. I'll do some test first, but just looking to start in the right direction to begin with. Seems both may work equally well.

Thanks for the replies so far, Tony

[Bruce Page]

As already mentioned, it depends on what you’re engraving and the look that you’re after.

The Camaster engraving, paint on aluminum was done using a diamond drag with 120° tip.

The Brady engraving was done with a 20° engraving bit.

Diamond drag is quick and simple and as Mark pointed out, more forgiving due to the spring loaded tip.

Vbit engraving requires more careful setup and a lubricant of some sort which can be quite messy.

I haven't done any brass but would expect similar results.

[Ross Moshinsky]

You want to engrave brass but you haven't mentioned how deep you want to go and what kind of machine you have.

So I'll give you a generic answer: buy a diamond burnished bit. It won't go very deep but it will give you great results and last a very long time. It's the bit we use on about 80% of our brass engraving.

[Tony Joyce]

Vbit engraving requires more careful setup and a lubricant of some sort which can be quite messy.


I hadn't considered the need for lubricant. I guess you would need a mister like for cutting Aluminum? Which is something I was considering adding anyway.

Thanks, Tony

[Bruce Page]

I hadn't considered the need for lubricant. I guess you would need a mister like for cutting Aluminum? Which is something I was considering adding anyway.

Thanks, Tony

A mister would be great to have if you’re doing a lot of metal cutting or engraving. For the little I do I just dab on some WD-40.

[Tony Leonard]

I have done a fair amount of engraving in brass and aluminum (wood, plastic, granite, etc.). I buy the cheap engraving bits on ebay. They have worked great for me. I also use them on circuit boards. They are certainly cheap enough to give them a try to see if they will work for you.

To qualify....I use a CNCRP Standard machine with a Bosch 1617 router. I usually engrave at ~0.015 or so. I've done a lot of text and some graphics. I use VCarve Pro to create the gcode. One thing to look at is when converting bitmaps to vector, you can easily end up with thousands and thousands of vectors! Also, the font type can affect the time required and the quality of the results. I never use coolant and I do use dust collection.

Never used a diamond drag, so I can't offer a comparison.

Tony

[Tony Joyce]

I have done a fair amount of engraving in brass and aluminum (wood, plastic, granite, etc.). I buy the cheap engraving bits on ebay. They have worked great for me. I also use them on circuit boards. They are certainly cheap enough to give them a try to see if they will work for you.

To qualify....I use a CNCRP Standard machine with a Bosch 1617 router. I usually engrave at ~0.015 or so. I've done a lot of text and some graphics. I use VCarve Pro to create the gcode. One thing to look at is when converting bitmaps to vector, you can easily end up with thousands and thousands of vectors! Also, the font type can affect the time required and the quality of the results. I never use coolant and I do use dust collection.

Never used a diamond drag, so I can't offer a comparison.

Tony

Helpful info Thanks. I have bought several bits on eBay, but never engraving bits. I definitely give that a try.

I'm pretty up on converting bitmaps to vectors, no problems there. No coolant, interesting. I'll probably do some tests without, since I don't yet have a mister to try.

Thanks, Tony

[Mike Null]

I probably shouldn't be posting this as I don't have a CNC machine but thought you might be interested in diamond drag with an engraving machine. Late last year I sold my rotary/diamond drag machine but missed the beauty of diamond drag work so I bought another.

394693

[Tony Joyce]

I probably shouldn't be posting this as I don't have a CNC machine but thought you might be interested in diamond drag with an engraving machine. Late last year I sold my rotary/diamond drag machine but missed the beauty of diamond drag work so I bought another.


Mike,
Thanks for your reply. It's all good.

The reason I put CNC router replies is I wanted to work within the confines of what I had, as opposed to suggestions to buy more equipment.

Thanks, Tony

PS: Nice job by the way.