What Type of Bits and Usage

[Ryan Barila]

Hello. I recently got a older engraving machine, Roland 2300a from someone. The person sent a bunch of tubes of bits. I am new to engraving. It seems there are three different types all have different angles marked on them. In the picture what type do I have and what would they mainly be used for?


I am looking to also purchase diamond drag bits for pet tags and other soft metals.


For Doamond Drag (i would turn off the rotating) bits 90 degree vs 120 degree? Choices are 1/5x5 or 11/64x8 or 11/64x7 I measure the bits that came with it at 6.5 inches long. Is roating burnisher bit better and cleaner look? Font would be fairly small355371

[Mark Sipes]

In the photo from top to bottom.

The first two cutters could be Diamond Burnishers. If you look on the end of the shaft you should see a tip thickness .030 .010 something like that. That is the thickness of the line the diamond will polish as it rotates on the brass or aluminum plate.

The center cutter is more of a drill/parallel cutter the size should also be on the shaft but if not a micrometer will tell you the diameter of the bit. Used to cut out plastics. Shapes, slots, holes....etc

The last three all seem to be Carbide cutters shaped for cutter fine lines in Acrylic, Hard to see if the tips are sized for cutting . The angle of the cut suggests lite fine materials. Acrylic & Plastics. The steep(22*) is designed so the deeper into the material the tip cuts the less change in line width...thus a finer letter allowing more detail... here is a link to cutter design.
http://support.rolanddga.com/docs/documents/departments/technical%20services/manuals%20and%20guides/antares%20fact%20sheet_cutter_anatomy.pdf

AS for the diamond tip angles stick with 120* ....... 90* is for hard materials - Stainless / 140* is for soft materials - gold.


Hope this helps.

.

[Kev Williams]

My opinions for what they're worth and with all due respect :)

First of all, the red caps for the most part have very little to do with the tools that may have been in the tube containers, the numbers on the first two caps have nothing to do with those tools--

The top two tools are diamond drag tools, not designed for rotating/burnishing. You CAN rotate/burnish with them, but all I've ever found that comes from rotating a DD tool is that it wears out faster. Usually they don't cut as well rotating because they seem to skid over the work. There's no tip width to these, only tip angles. 130° seems to be the most common, at least mine are- Another thing, the shafts they use for these tools are cheap and soft, they bend very easy, and as such don't run at 10k rpm in balance very good sometimes.
However, those in the pic, they've used carbide end pieces on the shafts, which I've never seen before. Something Antares might do?

This is one of mine, it's degress are marked at both ends--
355403355404

This is an older New Hermes diamond, this is the part number on the side, ends in 020 which has nothing to do with any cut width, but it MIGHT indicate a 120° angle-- don't really know...
355405

This is 2 views of a carbide burnishing tool, these are angle ground on 4 sides. This one I've hand-ground and it's not even close to being right ;)
355406355407
-but how it should be is:
side 1 and 3 are ground to form a sharp edge at the center (the cutting edge) and sides 2 and 4 are equally ground towards the center-
the closer to the center, the narrower the sharp edge and cutting width. When sharpened correctly, these are great for running across clearcoated brass plates and colored aluminum plates. The engraving has some good width, and gets thru any coatings to allow for blackening fluids (Aloxide etc) to blacken the engraving...


The center tool is pretty cool, I've never seen one quite like that, but it's essentially an endmill designed for drop-in spindles.
I have a couple myself, this is one--
355408
It's a full 11/64" width. This one I always found pretty useless, BECAUSE of the drop-in spindle, which doesn't actually 'hold' the lower part of the cutter. Too much vibration.
That smaller one has a crapload of chip clearance, which means it should work great, but also means don't try cutting any metal with it, all that clearance equals a very fragile cutter...

The bottom 3 are typical carbide tipped cutters, all look to have roughly 20° cutting angles. Tips look pretty worn, however, the overall tools themselves are essentially brand new.
The 3rd one is unique as it's a quarter-round tool, the top 2 are typical half-round. Quarter-rounds are great for engraving in general, as in, if you have trouble with a standard tool chipping the edges of anodized aluminum when engraving, try a quarter-round. With half the backside missing, they tend to cut much cleaner. The tradeoff, they sometimes wear faster, and sharpening them is tricky because of the tip width.

When it comes to engraving, especially with diamond tips, don't be afraid to experiment. But concerning spindle spring pressure, very light if rotating tools so they don't dig in, somewhat heavier pressure for non-rotating tools so they DO :)

[Ryan Barila]

Thank you for all the information. Defiantly helps clarify so much! After seeing the other photos. I am sure the first two in my photos are carbide burnishing tool, they have sides when up close like your photo. I will be ordering a 120 degree diamond for the dog tags I am going to be doing. What size do you recommend and any online store you recommend?

[Kev Williams]

I'll take your word and stand corrected on the burnishing tools, the tips are a bit blurry in the pic, and being burnishing tools explains the carbide ends :) -

Also, upon closer inspection, your quarter-round tool isn't-- the tool above it is casting a shadow making it look like a quarter round!
This is one of mine (pardon the crud, it's been working and I just pulled it for the pic ;) )
355448355449

[Mike Null]

You can get all your bits at Johnson Plastics.

http://www.johnsonplastics.com/engraving/engraving-supplies/cutters

[Kev Williams]

And I'll highly recommend the Antares cutters :)

[Mark Sipes]

If you purchase a diamond tip holder that mounts on your depth nose threads you can save on the cost of 1/8" x 1 1/8" diamond tips I last paid $10 each for mine (120*)