HOW MUCH abrasive filaments damage your nozzle! 

Noice !

I think premiere is a touch of hype ! I like it !

How to make such a shape ? DMG Mori 5-Achs Bearbeitungszentrum

For my (very may be clone e3d), i just pull up ''on cold'' 0.6mm nozzle fillamen without problems, for now its seems normal in 0.01+/- mitotoyo caliper

The spiral pattern is caused by a dull drill with way to much feed. The spirals of the drill try to get rid of the pressure and clog on the walls.

I was going to say the spiral was from a blunt drill but it has been said in detail above so I'll shut up now. Thanks very much for the great videos @cnckitchen

I was going to say: this guy sounds really sure about his statements, then I saw your name.

Genghisnico13 the “our” referring to the e3d nozzle was my first clue - people sound sure of themselves in YT comment sections allllll the time ;)

I just want to add ontop of your fine explaination about the helical pattern. -This is a great example why GPS tolerances (Geometric Product Specification) was invented, and specifically why it's important to have them specified when you make large orders produced out of China and the like. Not that it isn't necessary in all other countries though. :-)

Excessive feed rate, lack of pecking and worn tooling is the most likely causes, but materials like brass also have issues caused by their high thermal expansion. Materials do not heat evenly when drilling and tends to build up heat near the corners of the drill flutes during the machining process. Thus the materiel near the corners of the drill flutes is removed at a higher temperature so those areas expand more then the other areas of the cut. This leaves a smooth hole at the time of operation, but then when the materiel cools and constricts it leaves a helix or spiral shape that matches the drill feed rate. Brass and plastics it tends to become fairly prominent due to their high thermal expansion rates and high drill feed rates.

So they just jam a drill bit in there?

@@cherrify3498 sounds like it

this^^^^^^^^ It's so simple it's strange no one understands

It's not a great application for a form drill because there is a high ratio of diameter for the tip diameter and the body diameter of the nozzle and also because the tip diameter is so small. For a 1.75mm filament bore and 0.4mm outlet dia, one would have worse than a 4x ratio between the smallest diameter and the largest diameter on the form drill. This means that you'd really like to be drilling that tiny 0.4mm diameter a much larger RPM than you can run the 1.75mm diameter at because you'll exceed cutting surface speed limits on the larger diameter. This means that you have to plod ahead at 1/4 of your best drilling rate for that tiny 0.4mm end which is going to be doing a terribly ugly drilling job for the entire length of the nozzle because it's stuck to the end of the 1.75mm body dia. It would be far faster to blitz the back end of the hole with the 1.75mm dia for nearly the whole nozzle length, then go in with a 0.4mm to peck out the last bit of length at the end. Using a second tool position to have separate 1.75mm and 0.4mm diameters will be far faster with better quality drilling and much lower breakage of tools, not to mention that standard jobber drills are way cheaper than making a form drill. I think the spiral pattern is being caused by a cheap jobber drill being pushed too far past their sharpening regimen. There's no really good excuse because clean holes in brass with jobber drills is very easy with CNC. The level of tool wear management necessary really isn't high.

I imagine that drill runout will also cause a spiral. An extremely true and concentric chuck is needed for highly accurate drilling at such small diameters.

hello

giri nevass hi

If the drill vibrates, it usually makes cones. Like an hourglass shape. The walls of hole look like melted, probably drill was overheated during the production and left that weird pattern?

25 year machinist .. that pattern happens when the drill geometry is shoddy, specifically the lead on the spiral or the point being off center slightly and your feed is way to high. Brass has a tendency to grab when using sharp tooling. A way to mitigate the grabbing is to flatten the cutting edge slightly on the perpendicular axis of the cut. This is probably the reason for the over powered feed so as to compensate for that flattened cutting edge.

@@swould333 I can confirm that, worked a lot with brass in the past, it likes short stubby cutting edges and the unevenly sharpened chinese 1.75mm drill bit is far from that. High speed vibrations + eccentric forces combined with resonance from the brass grabbing and you get forms you could not imagine can exist!

@@swould333 yep.

@@swould333 curious if the good nozzles are cut in three procedures and that's why they have good surface finish and geometry that clearly wasn't taken off a shotty twist drill.

F Huber it most likely isn’t cut for brass and was trying to pull the part as well which combined with being cooked and probably dull

Some more insights as to how the wobble might have occurred: The geometry of nozzles lends well to lathes (and by extension screw machines), where wobble of both the part and the drill can be more severe vs with a mill. It's also likely that the stock used to make the nozzles is at the max diameter of the part to minimize material waste, and that thinner material would also wobble more. As for feeds and speeds, the high machinability of brass allows very aggressive settings without significantly shortening tool life (and that's great for minimizing labor cost, but bad for part quality).

@@tronique5736 most probably machined from hex bar

Also I bet the is not exactly round, but slightly elliptical due to the same reasons. I’ve learned the hard way as a home gamer that drilled holes are always bigger and never round.

Happy to help.

I think it’s worth noting though that those cheap nozzles are made by a very wide variety of manufacturers, and it may just be that the particular nozzles he tested were especially bad... I have only cheap Chinese nozzles, a big variety box of standard CR10 style nozzles, as well as one V6 style I was sent by mistake, and about 6 volcano style I bought for my Sidewinder X1. I just double checked all of the volcano and the v6 nozzle as well as a random selection of the CR10 nozzles and not a single one had that chamfer. I even double checked under a microscope in case I just couldn’t see it with my naked eye. I’m sure the internal bore of the nozzles is not as clean as genuine E3D nozzles, and there may be a difference in the internal angle, but at least it doesn’t appear that the no name brand nozzles all have that chamfer or that it’s even a common defect. He may have just received a defective batch or bought from a particularly bad manufacturer or I’m just extremely lucky... He’s 100% correct that you’re taking a gamble not buying genuine, but given that the cost of a single E3D volcano nozzle is about the same all of my Chinese volcano nozzles combined, it may be worth the risk as you won’t lose much money if they turn out bad. Though of course I do appreciate supporting the original creators. Also for example there is a massive difference in quality between the heat breaks especially on knock off E3D extruders vs the real ones that I think makes them an obviously better buy even at the in increased cost (my sidewinder for example has a PTFE tuve all the way through the heartbreak which is an issue for high temp printing, so I’m planning to upgrade to an official E3D all metal titanium head break which is actually about the same price as some of their nozzles somehow even though it’s a more complex part). Also it’s worth considering that I can buy the Chinese nozzles easily here in Colombia with local 1 day shipping, whereas to buy genuine E3D nozzles I would need to order from the US and import them, increasing the already higher cost due to reshipping and import taxes as well as significantly increasing the wait time to receive them if I need one quickly. I’m still planning to buy a few genuine nozzles to use as a baseline comparison against my cheaper nozzles to see if I get increased print quality, but I don’t think it’s fair to test a single brand of Chinese nozzle and then imply that all Chinese nozzles are manufactured that way or have similar problems. Many of them are perfectly fine from what I can tell (including from my own print quality which is quite good using only these nozzles). Anyway just my 2 cents.

James Crombie that's awesome! I thought that angle was really interesting. I'm guessing E3D have tried all sorts of angles to get one that works best, but I'd be interested in results from even more acute angles.

I have personally seen that helical pattern when printing on my makerbot cupcake with bent lead-screws. I immediately assumed that was the cause when I saw the cross section.

Also, unevenly sharpened drill bit does the job. Possibly they didn't even use center drill.

yeah no center drill would do it, i wonder boring it on our own would do any improvement

These are actually the new silicone socks, the closed ones are now called "pro" socks.

@@CNCKitchen Funny, I don't know what's pro about that. I had to cut away a mm or two of the bottom of every sock so far.

That's what I thought. And another option (which I'm going to try after fixing my printer) is to… Do the same with sandpaper.

@@JayOhm i have tried the sand paper but cant get it flat enough. Looks ok to the naked eye, but under a microscope you can see the rounded edges

Both angles point to an custom drill bit. (Which arn't expensive when you mass produce.) The default angle on a HSS drill bit is 118°. But there can be differences for hard and soft maqterial from 110° to 130°. Carbide drills normally use 140° tip angle.

Most spot drills have a 90 degree angle and are extremely rigid. Could be step one for E3D’s process...

You are correct. Machining bits can be 90 degrees.

That would make since.

With a finishing cut at 60

Vielen Dank!

Oh cool, gotta listen to it!

This is how the ruby nozzle looks from the inside: twitter.com/erikcederb/status/1125056521199673344 There is a point angle but then, there is a small, flat section. Interestingly the standard Ultimaker nozzles look very similar on the inside.

I can't get rid of stringing with eSun PLA+. Not sure if it's the filament though.

yes and if over extruding even a little bit the nozzle will drag more.

That means one should beware of excessive ironing, right?

^ This.

Thanks for your support!

Should work but probably not worth the effort if a good, genuine new one is just $5.