Diamond turning an acrylic dome

Taking a first cut on the outer surface a 150mm diameter 180 degree dome in acrylic, inner surface already turned. Nanotech 250 UPL, 2000rpm and 45mm/min

[@jimmydean9006]

Everything is so clean I can't even tell if the acrylic dome is spinning.

[@chrishoesel]

The spindle runs on air bearings. Super smooth.

[@justincouncell7608]

I thought the video had stopped due to this and the ultra slow feed rate

[@diditwork370]

There's vacuums sucking up all the dust.

[@peachmelba1000]

If you've ever seen acrylic being roughed out, it's like confetti flying everywhere haha

[@absolute___zero]

@@chrishoesel the proper spelling is "aighh beaghhings" (local joke)

[@drubradley8821]

WOW!!! This was extremely pleasing to watch... gave me the same pleasure that I get polishing chrome.... nice work!!!

[@TheShorts5555]

Bit late to the party, I know, but we use a virtually identical process to manufacture contact lenses at our company! In fact, the materials we use are water absorbent acrylic derivatives (copolymer diol esters of PMMA and such) that are turned when dry. Fully CNC diamond tooled lathes on both the BCOR and front optic surfaces, they don’t even need polishing except for the BCOR toric surface on some lenses, and the edges for comfort. Quite satisfying to watch if I get a spare minute away from the job :)

[@Metalloys]

should've set the camera on the other side.

[@andrewsimpson5436]

+A.H. Shukry You need a little bit of mystery :-)

[@Peter_Riis_DK]

@@andrewsimpson5436 But I don't! 😎

[@TheNefastor]

I don't think we'd have seen much more. It doesn't look like this process produces chips or anything but dust.

[@Peter_Riis_DK]

Jean Roch Yeah, well. That's what you can't see because of the camera position. Right?

[@TheNefastor]

@@Peter_Riis_DK sure but I was speaking from experience.

[@alexymetals1285]

Very nice part and process. I would recommend using a controlled waviness tool (0.1micron over 100 degrees) to avoid "Rainbow effect" or micro scratches.

[@andrewsimpson5436]

Thanks for the comment G, I'm always open to ideas. We use 120degree sweep and Non Controlled as I mentioned, I thought the waviness had no effect on finish, rainbow etc as that is down to the tool sharpness? What sort of components do you do?

[@argentosebastian]

Can you make this on a mill? Probably not a good idea isn't it?

[@peachmelba1000]

@@argentosebastian It could be done on a milling machine, however I think you would still have to do the final pass on a turning center, given the spindle speed required, and the need for a single point tool. If you had to get really creative, you could use a mill (and provided the workpiece geometry somehow allowed for it) you could mount the acrylic into a tool holder in the spindle, fix the tool in a vice or fixture on the bed, rotate the work in the holder, and use a tool path to follow the arc of the finished radius. The mill would have to be 5 axis capable, however, and it would not be as rugged a setup.

[@argentosebastian]

@@peachmelba1000 thanks for the advice. I'm thinking my best shot would be to CNC with the mill the best I can and with a fixture mount it on a manual lathe and finish it up with sandpaper. I would like to make a dome for the camera of my ROV kzbin.info/www/bejne/mn66e4Jjd6ilhKc

[@peachmelba1000]

@@argentosebastian No problem. I know some Santillis here in Nova Scotia. Nice people. Also, I used to make acrylic lense covers for sensors used in fiberoptic relays. They were very small, about 12mm in diameter. Any that came off of the turning centers that were hazy we would polish by chucking them in a jeweler's lathe (in a small plastic fixture). The best results came from using a lint free, or silk, cloth with Novus's three part polishing compound system. Check that stuff out.

[@arturvelten9039]

The finishing is just fantastic!

[@agstechnicalsupport]

Thank you for posting this beautiful video on Diamond Turning of an acrylic dome. As you see in this video, a very smooth, transparent and shiny surface has been obtained on the substrate after the diamond turning operation. That is what diamond turning is for ! This dome is probably used for a low end optical application similar to protective domes on camera systems or as a see-thru dome for some other application. In higher end applications such as aerospace, missiles.....you see other materials such as quartz being used to make such domes. Maybe some folks are wondering whether glass can be machined with a CNC. Apparently, yes it can, but it is trickier than metals and metal alloys and instead of carbide tips used in metal machining, generally diamond tips as in this video are used on lathes and machining centers. Manufacturing precision optics is more demanding than metal parts manufacturing, because optical surfaces must be clean and very smooth. Optical component geometries require high accuracy and small tolerances because when mounted, any small misalignment or tilt can deflect, reflect, refract the light in unwanted directions. Also since optical components are often coated with metal or metal oxides to act as mirror or filter, the surface roughness has to be very low to allow smoothly coated surfaces. Also cleanliness and precautions against contamination are critical and there are many cleaning steps involved. A small mistake or contamination, scratch, chip, defect or else can easily render the final product as scrap and repairing optical components is much more difficult or impossible as compared to metal parts. Especially when optics is made for high power laser applications, any small defect or contamination can cause a local burn at the defect / contamination site and result in downtime of the apparatus in which the optics is mounted. So, to obtain optical grade surfaces, the way to go is Diamond Turning among some other techniques. Please visit our KZbin channel by clicking our logo on the left for other good content on manufacturing techniques and engineering content.

[@jeronimomurruni]

I love you KZbin algorithm

[@atenrok]

Yeah... I have no idea why I'm here either 🤷🏻‍♂️

[@andrewsimpson5436]

I have an algorithm?! :-)

[@atenrok]

@@andrewsimpson5436 no. An algorithm has you.

[@wjcarter3]

Hey we're looking for a similarly sized optic to be diamond turned. May I ask which company you work for?

[@paulpothier123]

that's a prity fancy light bulb cover

[@priitmolder6475]

This is most likely a lens for a camera. "Why don't they heat polish or buff it with wheels?" Because those processes are very uneven. Using a diamond lathe with a known end point width and angle. Knowing the feedrates and pressures. That combines to a very predictable distortion, that can also be measured in Ra (or surface levelness).

[@MadHatter123456]

+priit mölder No, it's a porthole for a submarine.

[@andrewsimpson5436]

+MadHatter123456 my money is on priit being right.

[@MegaWhathell]

what a fantastic video!!!!!! what i want to ask...would it be possible polishing PMMA with 2 flute/carbide/flat endmill in CNC machine just as you did in that video??

[@CharlesBusada]

It's right at 1:08 that this gets good. You can see the bit.

[@0relaxis0]

Nice, but could I making the same surface in glass ? if yes, what parameters and cutter? thx

[@andrewsimpson5436]

No, glass needs moulded or ground

[@thefattesthagrid]

it's so beautiful..

[@getitdone6255]

is the surface quality on the top of the dome good ? (i mean the smaller radius of the doom) Because in lecture we lurn RPM are linked to the many parameters (included the radius), but as you cannot increase the RPM too high with the limit of the machine the dome might look bad on the top ? you have to polish it after using the lathe ? sorry for bad english i'm outside native english ppl

[@andrewsimpson5436]

I'm running at a constant speed and feed over the whole surface and the finish is still good at the centre. I do give it a light polish by hand after turning.

[@gomezpiro]

“ nice finish 👍🏼

[@amerikorean5606]

How many waves/ how good RMS can you achieve with arcylic material? and what kind of other materials do you guys handle?

[@sparkyjshaw]

Great video! Was there a finish polish after this cut and if so what method was used?

[@andrewsimpson5436]

Hi Jack, yes it gets a light polish with 0.5 micron diamond paste on formed dollies covered with microfiber cloth.

[@DriveSMR]

When you can see people in the reflection….amazing

[@rextransformation7418]

What is that dome for? I doubt just for aesthetic reasons...

[@schlaznger8049]

Now that is a cool video. Thanks

[@glenbrumby1]

Can you please share the manufacturer and part number of this tip tool? We CNC turn many 100s of acrylic lenses each year and then hand polish them. This would be a big help for us knowing the tool you are using so we can give it a try. Thanks.

[@philmeiklejohn]

KY Diamond is a good vendor, but it has more to do with that lathe they are using than the tool honestly. The lathe shown here programs in .01 nanometers. You should be ok if you try acrylic or other soft materials but be careful with the diamond on a regular lathe if they chatter at all you can chip the diamond pretty quickly. Even though these chips may be extremely small they will dramatically change the surface finish you see here.

[@slipstreamvids7422]

Reminds of parts we made for KLA Tencor

[@aserta]

That's very impressive. :)

[@mechanical1955]

That is amazing what a finish

[@ObsidianParis]

Is that played backwards ? :-)

[@andrewsimpson5436]

Another Flat Earther? LOL

[@petkopiryankov]

It seems so

[@andrewsimpson5436]

@Fester Blats What's your background? Tell me all you know about Diamond turning,, NO wait, I'll tell you what you know. Zip, Nada, Ziltch!

[@TFKofBD]

Is that a mistmatic cooling system? I am interested in specular finishing but have no experience in it whatsoever. What would you recommend to a college student who has access to CNC equipment who wishes to try something like this?

[@TFKofBD]

Rota Kravitz hahah, highly unlikely. We just have a Clausing Metosa with a Fanuc control system in there. What usually limits such finishes?

[@TFKofBD]

Rota Kravitz Some pointers please? like I said, still learning. A few pointers would be great.

[@TFKofBD]

Rota Kravitz Haha, fair enough. Been reading up on Nanotech Lathes. 6pm Precision!!!! Thats simply amazing to say the least. Time to go back to the drawing board

[@andrewsimpson5436]

As You see and Rota pointed out it very hi spec and the display is in NanoMeters. The controllers and drives have virtually no backlash and even the spindle has to be ballanced to prevent any throw

[@nomdeplume4726]

Any backlash would be from drag of the bellows and is immeasurable by any practical means.

[@jayfelcy]

Awsome

[@somasundaram5573]

I guess , this tool gives the best finish for machining acrylic material .. Can please tell me the exact name of the tool used here.. So that i can purchase and do the same thing .. Please ....

[@andrewsimpson5436]

Hi, I use a Natural Diamond, non-controlled, with a 0.5 mm radius tip, 0* rake and conical clearance, 12+1/2* front clearance. We use "Contour Fine Tooling" to supply them

[@phuturephunk]

Jesus, that must be indicated to within a nanometer of true. You can't even see it rotating.

[@donaldasayers]

Beautiful.

[@Voxters]

Awesome! Absolute Awesome! RPM? Feed? Bearings or Magnetik or Oil mounted Spindle? Feels like 3000rpm with totaly zero Fibrations.

[@bloodaid]

Look description.

[@brunomarzano9859]

Apologies if repeated, but is the dome about 2" thick?

[@andrewsimpson5436]

Hi Bruno it's 24mm thick.

[@magnusklahr8190]

Amazing!

[@joseluisrosasvazquez119]

hi, where is this done? i need something like this, i need to do a prototype…

[@horseracingpeters9971]

jose luis rosas vazquez

[@horseracingpeters9971]

I can do something like that for you

[@Racingboom]

Does acrylic get hot when it’s being cut?

[@hopsta5628]

Yes

[@hopsta5628]

@Hector Gutierrez the spatter of hot acrylic coming from the high speed cutting disc of a hand held grinder suggests otherwise.

[@KazzArie]

Is that large going 100krpm?

[@kotti8850]

@ask3lgolf - i would like to use your video in a blogpost. Would that be OK for you?

[@andrewsimpson5436]

That should be fine, what is the blog subject

[@kotti8850]

@@andrewsimpson5436: 4,5 possible ways to produce a plastic optical prototype. Maybe you can send me your business contact details also to: [e-mail]

[@andrewsimpson5436]

@@kotti8850 that's good but we only do internal work.

[@sling9070]

using Sumitomo's diamond I get a similar finish on my Fox Model# W1758 in the garage.....of course I really have to slow the feed down

[@andrewsimpson5436]

That's good to know, do you work to nanometers or microns?

[@runcycleskixc]

we are looking to diamond turn an acrylic ellipsoidal dome at sub micron precision for a mirror prototype (wanted BK7 initially, but decided to try something simpler first). The dimensions of the 'egg' are about 10-20 mm, and 0.5 micron precision would be sufficient. Is there a keyword to find you on the internet? Otherwise, I am at my runcyclexcski at gmail (the order of letters is slightly different).

[@WHOISTRANE]

how it works? because of chemical vapor stream from that vinyl tube?

[@thugasaurusrex6004]

WHOISTRANE it's a diamond tip on a lathe lol

[@douro20]

Nope. This machine has an air bearing spindle and hydrostatic ways and is cooled to within 1/1000 degree Celsius. It can achieve surface finishes better than 1 nanometer and has positional accuracy better than 15 nanometers. It is possibly the world's most accurate series-production machine tool.

[@Sketch1994]

Mind = Blown!

[@marcin_lukasik]

This is mental.

[@JoeyC-ss2tl]

Marcin Łukasik nope

[@thugasaurusrex6004]

Marcin Łukasik yea seriously. It's insane how clear that came out

[@DTOptics]

What was the dome used for?

[@ask3lgolf]

Hi, afraid I can't say too much but it was for an underwater camera

[@DTOptics]

ask3lgolf Ah cool. I know what ya mean. It is almost odd for me to see such a 'huge' part on the spindle. Most of the parts I work with are between 0.010mm and 4mm. Cool looking dome though.

[@ask3lgolf]

Yip, I know what you are saying and that what I do is bigger than the norm. That is about 148mm OD with a 72.5 outer rad and 47 inner rad, goes under water to 5KM Done up to 330mm OD but thats about as big as can be done without using riser blocks for the spindle and I don't want to try that!

[@DTOptics]

Ah yeah. Grab a 350FG then you can just raise the Y axis :p

[@imabeapirate]

snowglobe

[@AspentheGuardian]

so satisfying

[@Soupie62]

Can you do this on a mini-lathe?

[@delron44]

outstanding

[@InsightVision1]

I have domes I need to machine to this quality. Who does this process of diamond lathing? what would it cost per dome? we have rough machined and or injection molded domes. But we need this finish. Help me out with ideas guys?

[@Teth47]

InsightVision1 Just polish them after rough milling, 600 grit, 1200 grit, 2000 grit, then Novus 3, and 2 polish, in that order, you should get a optical finish.

[@andrewsimpson5436]

Teth47 What you "milling" them on?

[@Teth47]

Andrew Simpson A... A milling machine? What else does one mill something on?

[@andrewsimpson5436]

Teth47 Obviously a mill but what type and cutter? Only ask as a lathe would be far more suitable surely?

[@Teth47]

Andrew Simpson Absolutely. I posted that comment late at night, terminology got mixed.

[@j0ule]

Who made this? Looking for a good diamond turner.

[@andrewsimpson5436]

I am the guilty button pusher :-)

[@thugasaurusrex6004]

That's insane

[@rahulbindhu]

Turning and polishing at the same time

[@andrewsimpson5436]

Just turning.

[@Nightspyz1]

how did it not shatter to a million pieces as soon as that thing touched it

[@andrewsimpson5436]

It's perspex so not very brittle and the bit of the "thing" that hit it as you say is a diamond lapped to be exceedingly sharp.

[@Squawk_Box]

Why did this get 12 downvotes? What qualification did this demonstrative video fail that left 12 people that upset?

[@rodstartube]

with all that CNC manufactiring time, it must be an expensive product.

[@bringinghomethebananas]

Diamonds are for tools!

[@ShopperPlug]

what will this dome be used for?

[@ask3lgolf]

for a camera to view through that is underwater.

[@ShopperPlug]

@@ask3lgolf Wow, I knew it was for a camera of some sort. It blows my mind that it requires ultra precision machine to make such dome (for surface finishing). I always questioned and wondered why those super clear videos of underwater footage of marine fishes are so crystal clear and vibrant inside a dome cover. I originally thought it was made of glass but I have seen plastic as well. Well worth the money if people knew why it costs so much.

[@ask3lgolf]

@@ShopperPlug We have made cameras that go to the Marianus trench, 11,000M but they are mainly for industrial, oil/gas industry and the std product is rated to go to 4500M also exploration so in general footage of the Titanic etc. Glass is also used but Acrylic is a little more predictable and can withstand a small impact better than glass under pressure, so our designers have always said.

[@ShopperPlug]

@@ask3lgolf Wow, truly state of the art engineering for most demanding tasks used in the industry.

[@gopalshukla3864]

nice

[@Meph648]

2000 RPM steady? You don't CSS?

[@andrewsimpson5436]

+John Doe Yip, fixed revs. That was the advice at Nanotech (long story but the basics are) so as not to alter any forces on the spindle which would carry on to affect the form. I did try some G96 and it threw up a few random colour rings so sticking with 97

[@Meph648]

Is it an issue with the lathe itself? We can't see very much but the thing doesn't look super strong/steady. I'm used to hard part machining in lathes and turning centers with 30+hp that can take over .200" DOC in steel without even breaking a sweat. We did some acrylic parts on milling machines, nothing like lenses though. I always imagined any lens or dome like that would need some sort of finishing with lapping compounds or something...

[@andrewsimpson5436]

Aye I do steel and Titanium on std cnc lathes but the diamond turning m/c works to 0.000001 of a mm so the torque changes show up on the finish and we balance the spindle to keep things true at that level. We used to polish on lapping machines with 0.5 micron paste but with diamond turning we can take a finished lens straight off the m/c without polishing. A great bit of kit if you need VVVV high precision.

[@Meph648]

Ahhh, that explains things. Thanks man. You sure about all those decimal places past the mm are correct?

[@andrewsimpson5436]

+John Doe Yip, 1 millionth of a MM, a nano meter, hard to put that back into inches! I'm a CNC turner too but this is just turning on steroids. Need to be temperature controlled as we aim to have the tool within 1-3 microns below centre and centred to the same tolerance but once you get used to the measuring gear it might as well be 10 thou" LOL You get used to it but just have to start thinking about it in VERY small detail to start. And what I'm doing is just the start!

[@FtheWord]

What type of coolant do you use in DT process for this acrylic dome?

[@andrewsimpson5436]

No coolant or cutting fluid, it's dry with air blowing the cutting away from the tip and extracted away by a vacuum cleaner.

[@FtheWord]

Interesting! Thanks for the infos. Also for the tools supplier information...Currently I manufacture only ZnSe and Germanium and I want to start DT testing on acrylics (Zeonex, polycarbonate, PMMA etc.). Do you DT also Silicon?

[@andrewsimpson5436]

We use Contour Fine Tools for our tools, Natural diamond, 0.5mm rad, can't remember the other specs but just tell them what you are machining. I'm only doing Cast acrylic/pmma , have tried Polycarb but it's too abrasive, might work with white spirit as a cutting oil. Its better moulded as it sounds Zeonex is. Good luck

[@chase_h.01]

This is why you dont bother getting a lathe without cnc

[@thomasstuart6861]

Not all machine work is production work.

[@blade400guy]

What feedrate was that finishing at ??!!

[@ask3lgolf]

That was roughing at 50mm/min, the finishing cut is 20mm/min

[@blade400guy]

ask3lgolf looks good mate very nice finish .. What was the feed rate per rev??

[@ask3lgolf]

that would be 0.01mm/rev but we just program at per minute for more control.

[@blade400guy]

ask3lgolf makes sense no wonder the insane finish .. slowest feed I've used on a job was 0.04mm per rev haha ... if you don't mind me asking what is the part for ??

[@ask3lgolf]

It's another world from standard machining, the finish is more due to the sharpness of the diamond doing the cutting. It is set up 0 to 2 microns below centre to prevent chipping the tool but you do get your head round it :-) It's a viewing dome for an underwater camera with a head that pand and tilts to point the camera out in the direction required.

[@rolandjollivet38]

It didn't finish the last few mm... not quite a dome

[@andrewsimpson5436]

Last few mm at the beginning or at the end in the centre?

[@BrianMDPhD]

What IS this magic!?

[@magnusklahr8190]

BrianMDPhD ?

[@softwarepole]

Why this tool is on the wrong side?

[@andrewsimpson5436]

+drzaca It's the right side for the rotation of the spindle :-) What makes you say the wrong side?

[@softwarepole]

+Andrew Simpson usualy the tool works on the front side, not on the back of cnc

[@andrewsimpson5436]

+drzaca All CNC lathes I've used the tool is on the back but that aside, on this m/c it works on the front side when it's turning the inside in M4 :-) Working on both sides saves time resetting the tool and fits in with with the WEC measurement plate. The machine is just as happy working both sides of the centre.

[@devildog9595]

How about playing it in reverse so we can really see what happened

[@andrewsimpson5436]

You're so funny and such an original thought LOL

[@RevanTK421]

Am I the only one that thinks he is playing the video in reverse?

[@andrewsimpson5436]

No, Mr Zassrob said it a year ago, he even claimed to have a DT machine at work and said it couldn't do this. That said he hadn't seen the machine work and he disappeared after that. Funny thing is I've no idea how to get a film to play backwards!

[@brocksdaddy081910]

I'm new to this video and reverse was my initial thought as well.

[@brocksdaddy081910]

At 32 seconds you can see material being removed if you look really close but man its tough to tell

[@meeher1983]

Hi I can u make 1 machin for me . How much it will cost..?

[@emmanuelfaure]

Hi 9gag! :D

[@hirmelihoi2287]

hiya!

[@matzoman3401]

Pure porn. love it.

[@atenrok]

Acrylic porn 👈

[@RogueBro]

People with ocd should be shown This as therapy

[@Shreyam_io]

Fool will say "reversed" Reversed

[@jakub0306]

This Video its playing backwarks

[@andrewsimpson5436]

and why would anyone want to get rid of a clear finish for a grey finish? I could do that with some wet or dry not a $250,000 machine. PS the world is round.

[@sliccmang8176]

Someone please explain to hot the literal fuck this got into my suggested videos? I’m honestly lost asf

[@alejandromedina4597]

This is obviously reversed.

[@andrewsimpson5436]

Out of interest, what is your background and knowledge to lead you to that conclusion?

[@dasdingsuper6312]

That Video was played and uplaoded reverse....

[@andrewsimpson5436]

Show your ignorance somewhere else please.

[@dasdingsuper6312]

Dude stfu. You know iam right.

[@andrewsimpson5436]

And what knowledge and insight do you have on the subject to think it's not running forward?

[@dasdingsuper6312]

Because i work at a Company who does Diamond Turning. In my free time i did the same, in all ways. Went in all situations from Clear to not clear. Even with full RPM. This Video is uploaded reverse.

[@andrewsimpson5436]

Why could you not go from grey to clear? What lathe and what tooling are you using?