[Graphicman]

Hello guys

I was really wondering if anyone has actually tried these pyramid tools (V bit engraving)
10pcs Carbide Steel 60 Degree 1 8" Router Pyramid Engraving Bits CNC Machinery | eBay

I have seen these tools being sold in different places and sellers
the company/sellers claim they are made from sub micron ultra fine carbide grains
most importantly they have a very narrow tip 0.1mm , probably the sharpest i have found so far to be sold
at the same time they come in 1/8" or 1/4" cutting diameter, which means that they can be used to cut with their full cutting length not only their tips
company/sellers clams they can be used normally with wood, plastic, brass, copper and even iron!!

-1st question
Is it really possible that these cutters can actually even cut anything? I dont see any sharp cutting edge,
it might make more sense if they cut only shallow depths with there tips
these cutters are amazingly cheap, 10 of them equal the price of 1 of the normal v bits if not less
like here
1 8" 1250" Carbide 2 Flute Micro Drill Mills 60 Degree Point Kyocera | eBay
I used to use this tool, after some research it seem it has a tip diameter of 0.3mm (3x the 1st one)
however it did not last long and its tip was broken in the middle of a cut, so it is almost useless now for me, as I dont need it for chamfering
I am basically looking for a 0.2 or less tip diameter cutter that can last better than the Kyocera one
I have emailed Kyocera about this issue and requested a cutting condition (in case i was using it wrong) but they never replied!

So at the end I thought if any has tried these cheep chines cutters it will be very good,
because i believe their tips should be much more difficult to break because of their different geometry at same time they have very narrow tip 0.1mm
it also has 3 edges instead of 2 for Kyocera
but I still can not imagine if they can actually cut anything, I also failed to find any video for them

-2nd question
what would be the most suitable V bit to use in Al, brass or copper (light metals) for 1 to 2mm depth of cut at most?

-3rd question
10x Bottom Carbide PCB Board 30º Engraving Bits CNC Router Tool V Shape 0 3mm | eBay
are these V bit are used only with pcb or it can be used with deeper cuts?
why they have such geometry? (just curios)

-4th question
what would be the best engraving strategy for the longest life time of the cutter and to avoid tip breakage too?
would I step down all the way to the desired depth and feed slower or have it in multi steps?
what about rpm speed ?

Hope to hear from you guys what do you think about it

[RCaffin]

Ooh, cheap and a bit nasty.
They may cut some softer materials. They may smear some others - plastic at high speed when they get hot for instance.
That price suggests the carbide is kinda brittle. Been there before - dead easy to break tips off.
0.1 mm tip - yeah, IF and only IF the tip is ground centred, your collets have minimal TIR, and the moon is in the right phase.
Cutting iron? Dreaming imho. Blunt in 5 mm, if not broken.

PCB cutters - similar comments all around.

Kyocera: good brand, very nice finish. You could also try Precise Bits.

V-tips in general: rather doubtful. I tried, for PCB tracks, but went with Precise Bits milling cutters in the end.

Cheers
Roger

[Graphicman]

Ooh, cheap and a bit nasty.
They may cut some softer materials. They may smear some others - plastic at high speed when they get hot for instance.
That price suggests the carbide is kinda brittle. Been there before - dead easy to break tips off.
0.1 mm tip - yeah, IF and only IF the tip is ground centred, your collets have minimal TIR, and the moon is in the right phase.
Cutting iron? Dreaming imho. Blunt in 5 mm, if not broken.

PCB cutters - similar comments all around.

Kyocera: good brand, very nice finish. You could also try Precise Bits.

V-tips in general: rather doubtful. I tried, for PCB tracks, but went with Precise Bits milling cutters in the end.

Cheers
Roger

yes precise bits might be the best i found so far but very pricey and you must buy in bulk (50$+)
I am looking for a cheaper alternative if possible as there is no grantee for breaking the tips specially on these traditional cutter (the have very thin cutting tips)

But have you actually tried these pyramid cutters yourself or just imagining?
please find this link because it seems very promising to me

Making Pyramid Engraving bits - Home Model Engine Machinist

[RCaffin]

Precise Bits: from Soigeneris for small orders. Soigeneris
These particular cutters? No, but quite similar.
The link - I think he was using good carbide, but check the micro-photos anyhow: much smearing.

Cheers
Roger

[Graphicman]

Very good site indeed, if these cutters does really last then it is worth every penny
since you have been using these bits, what cutting conditions do you suggest specially with the stepping down?
My spindle is only maxed at 24K rpm, would that be enough?

thank you very much for your input

[RCaffin]

RPM: whatever you have got! I think they are rated well above 24k. I can't get anywhere near that myself.
I rather like the PB tapered-stub end mills. They did a much better cut than the V bits, although the PB V-bits were not bad.
On the other hand, some of the Chinese 0.1 mm V-bits were off-centre by about 0.3 mm! Ah ... yeah, right.

Cheers
Roger

[Graphicman]

so you have not tried the PB v bit but tried the Chinese ones?
it those chinese ones are not properly centered then it is better to DIY using the good carbide broken bits I own already
my spindle run out is very low 0.005mm, so that should not be an issue

I have no idea what is a tapered-stub end mill is, I am happy with my Kyocera other bits I have, the onl problem is the v bits (it is quite challenging everywhere i believe)
but no idea about the step down with v bits?

[RCaffin]

so you have not tried the PB v bit but tried the Chinese ones?

I have USED the PB V bits and I haver USED the PB tapered-stub bits, and I have used similar Chinese V bits.
The PB bits all worked fine.
The Chinese ones were desparately prone to breakage. Their high TIR may have had something to do with that.

If you haven't tried the PB tapered-stub end mills, give them a go. I was doubtful at first, but I ended up convinced.

Cheers
Roger

[Graphicman]

Ok got that
"I rather like the PB tapered-stub end mills. They did a much better cut than the V bits, although the PB V-bits were not bad."
but I can not understand how you compare the Stub End-mills with a V bit cutter? (confused)

[RCaffin]

OK. I was cutting out tracks on copper-clad fibreglass laminate: in other words making printed circuit boards.

Cheers
Roger

[Graphicman]

Ok but caan you tell me what would be better to do when V engaving lets say 2mm deep in copper/brass, 1 pass or multipass? what feed do you use ?

[RCaffin]

2 mm deep? The copper layer took a cut of about 0.06 - 0.08 mm!
Basically, I dunno about 2 mm deep!

Spin - all I could do was 3000 rpm. I have a 4-axis mill, not a router.
Feed - slow. I did not really need speed. I could afford to take my time.
What I wanted was a clean cut between tracks and no broken cutter - they are not that cheap.

What to do? Spin as fast as you can, and creep up on the feed until things start breaking. The usual story.
Multi-pass? Yeah, could be a good idea.

Cheers
Roger

[Graphicman]

I agree, but I dont think a multi pass would be a good idea
think about it, this way you will just keep using the tip of the cutter while the rest of the cutter never see the metal
so i think by this way you will just shorten the tip (the most important part) lifetime by the multi pass factor, if you do 4 multi pass then the lifetime of the cutter might be shorten to the quarter.
I think the load on the tip is the same in all cases with a shallow or a deep cut, the only difference is that you are using the whole cutting length, but we should feed slower, spindle power should not be an issue though, because these cutters are usually small, just an idea, one more thing to mention is fluid cooling, i have never tried to use a coolant, but would love to know if that would really help in the cutter lifetime

[RCaffin]

You may be right. I don't have a lot of experience in that area.
Your best bet would be to email Jeff Birt at Soigeneris (see web site) and ask him for advice.
You can tell him I sent you ... :-)

Cheers
Roger

[Graphicman]

sure i will
thank you very much

[victorofga]

you can get better than those bits..

try engraving bits.. they make better and cleaner cuts..

these pyramid bits wort as much as you would sharp a framing nail and use for milling..
its my opinion..

try to buy on ebay a ten set of engraving bit, they cost ususally 10-15 dollar the ten..

they selling thoushands of.. so I guess they must work..
I use them myself too..

because they just snap same easy like a 25 dollar bit.. but on the end I can break 15 bit before reach the price of a good brand bit..

[Graphicman]

exactly and that is what i was trying to say since first post!

I would say these pyramid bit seems to work yes, but I think they are not meant to cut deep
I am thinking because as more deep as you go as more chip load you need to remove because the cutting diameter is getting wider and since these bits does not have proper groove they will tend to push the material rather than cutting it out, so for small cuts they should work fine and I THINK they should not break as easily as much more expensive engraving bit because their tips are much more secured, so i am just wondering when you say that they snap same easy like a 25 dollar bit!

[popspipes]

Hello guys

I was really wondering if anyone has actually tried these pyramid tools (V bit engraving)
10pcs Carbide Steel 60 Degree 1 8" Router Pyramid Engraving Bits CNC Machinery | eBay

I have seen these tools being sold in different places and sellers
the company/sellers claim they are made from sub micron ultra fine carbide grains
most importantly they have a very narrow tip 0.1mm , probably the sharpest i have found so far to be sold
at the same time they come in 1/8" or 1/4" cutting diameter, which means that they can be used to cut with their full cutting length not only their tips
company/sellers clams they can be used normally with wood, plastic, brass, copper and even iron!!

-1st question
Is it really possible that these cutters can actually even cut anything? I dont see any sharp cutting edge,
it might make more sense if they cut only shallow depths with there tips
these cutters are amazingly cheap, 10 of them equal the price of 1 of the normal v bits if not less
like here
1 8" 1250" Carbide 2 Flute Micro Drill Mills 60 Degree Point Kyocera | eBay
I used to use this tool, after some research it seem it has a tip diameter of 0.3mm (3x the 1st one)
however it did not last long and its tip was broken in the middle of a cut, so it is almost useless now for me, as I dont need it for chamfering
I am basically looking for a 0.2 or less tip diameter cutter that can last better than the Kyocera one
I have emailed Kyocera about this issue and requested a cutting condition (in case i was using it wrong) but they never replied!

So at the end I thought if any has tried these cheep chines cutters it will be very good,
because i believe their tips should be much more difficult to break because of their different geometry at same time they have very narrow tip 0.1mm
it also has 3 edges instead of 2 for Kyocera
but I still can not imagine if they can actually cut anything, I also failed to find any video for them

-2nd question
what would be the most suitable V bit to use in Al, brass or copper (light metals) for 1 to 2mm depth of cut at most?

-3rd question
10x Bottom Carbide PCB Board 30º Engraving Bits CNC Router Tool V Shape 0 3mm | eBay
are these V bit are used only with pcb or it can be used with deeper cuts?
why they have such geometry? (just curios)

-4th question
what would be the best engraving strategy for the longest life time of the cutter and to avoid tip breakage too?
would I step down all the way to the desired depth and feed slower or have it in multi steps?
what about rpm speed ?

Hope to hear from you guys what do you think about it

I use a lot of the single flute engraving bits 60 and 90 degree from china, but cutting copper they may tend to smear or push it out, as a rule copper doesnt machine well unless its the free machining grade. I buy the 10 for 10 dollars from china, they arent the best quality but they get broken or dulled regularly so I can t see spending a lot of money on them. The pyramid ones have multi flutes but the cutting angle is obtuse so I dont think they would cut as well in some materials, but I havent tried them yet, just my opinion.

[Graphicman]

"single flute engraving bits"?

I have not seen any of these before would you please send a link?
I am interested in the 60 degree one

what do you cut with them then? for me copper/brass are much easier to cut compared to AL

[popspipes]

I use them mostly in aluminum, some steel, I use them on a Tormach milling machine and the spindle is only 5100 rpm, so you have to limit your travel ipm. About 5 ipm does a nice job, I have run 10 ipm but the finish isnt as nice. I also limit the plunge to about 20 percent of the ipm. The doc I use is around .010 per pass and a .003 cleanup pass.

Some aluminum will gum up pretty bad, I use 6061 t6 mainly and spray the work with kerosene or fuel oil from a spray bottle.

10X Carbide PCB board 0 3mm 90 Degree Engraving Bits CNC Router Tool V shape | eBay

or just type engraving bits into the search or subject line in ebay.com .and it should bring them up