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Can the Precision Matthews PM-728VT CNC kit able to do micro machining?

Every single post you jump into you make some stupid comment. Then hijack the thread with your lame pictures. Everyone but you understood his comment on the picture.

Making a claim of precision on the level they are, and the claims made on the website then using calipers, verniers at that would not be accepted in any precision job seeking an inspection report. Let me guess, you would measure parallelism doing this and just jumping from edge to edge! I don't care what China says, were not there.

You seem to only post to argue followed shortly by self boasting then promoting China.
If you don't like a post please report it...don't fan the flames.
Ok, I looked up their website:

If you scroll down a bit you can see an image showing the tooling marks that reveal how they're made: they're stood up on edge and cut with slitting saws.

Wow. Nice investigation. Novice like me wouldn't be able to catch these obvious details. Wonder what kind of slitting saws used here to make 0.2mm gaps.

I guess right now I want to make larger 0.6mm micro fin gap channels and 1mm thick walls, would be more easier and practical.
There is another best PC water cooling company called "EK" which uses 0.6mm gaps which is much larger than the original one (optimuspc) I posted:

These CNCed water cooling blocks are used in world's top of the line graphics cards (such as RTX 4090).
I wonder how much those thin fins actually contribute to better heat transfer to liquid, since the finer you go, the less tall they can be till you simply don't get any heat transfer from extra surface area that is too far from the heat source to actually conduct anything
and I also think that cutting them with rotating tools is a big waste of time, skiving seems just way more economical, especially if they retail for 50$

Excellent observation. I just asked myself this today when I saw a company called "EK" are seriously selling $400+ water blocks to my great surprise have super larger micro fin gaps of 0.6mm. These water blocks are used in today's most expensive graphics cards (RTX 3090 and 4090) any man could buy which costs around $1,000 to $3,000. People are buying them to cool their GPUs.

So I guess 0.6mm is the optimal parameters (which "EK" even mentioned) for water cooling to prevent liquid clogging up since people use all types of liquids to make their water cooling setups really stand out.
Such deep cuts with mini-end mills would take so much time that the work could not be profitable.

Thanks for the reply.

Just want to be clear that I am not going in competition with a multimillion dollar PC water block company which have many engineers doing R&D on this. I have no interests to make thousands of water blocks lol. :willy_nilly:

I just need an affordable reasonably precise CNC which can mill aluminum and acrylic so that I can make customer specific custom PC water cooled builds. Used for other reasons like making water cooled manifolds and distribution plates, these doesn't require ultra precision tolerances but needs to be able to mill acrylic and aluminum reliably.

I was just curious if micro fins which have space gaps of 0.2 to 0.6mm could be possible to be milled or sawed, this way I could make CPU/GPU water blocks all milled/sawed from one copper/aluminum water block instead of buying discreate precision milled water blocks and attach it to larger water block.

Here is an example of the micro fins and the entire water block all milled in one block of aluminum:

One of the best companies making modular small micro fin water blocks are charging only $50 with 10 year warranty, that's excellent pricing since custom PC water cooled builds can be charged for thousands of dollars for one client alone. I rather pay the $50 Optimus Gen 2 cold plate and design the main large water block to attach with it.

Example how the micro fin cold plate water block is attached to the larger main water block. It is a two piece system which is great for repair:

The reason why I want to make everything in house is because all PC components and water cooling designs are all unique for each customer who are paying top dollar for one PC water cool build and there will be many instances where buying off the shelf pre-made large water blocks are not ideal for the design.
whatever the pissing contest you guys are having - why the heck would one bother trying to tool up with a whole new machine+tooling+material+whoknowshowmanyscrewups just to save $50? I as much of a cheapskate as anyone on here, but that flat out doesn't make any sense to me. Even if it was feasible for a hobbiest to do, which is isn't.

LOL. I agree, the project charged to the customer is thousands of dollars and one crucial component only costs $50. Really makes no sense to cheap out and make one yourself. Also the $50 micro fin cold plate they charge was designed for people like me to use it for any PC cooling projects so that it can be used for demanding specific custom water cooling design.

I simply just asked the question out of great curiosity. But now that these $50 parts are out of stock, asking to make one inhouse isn't so bad.
Only if you thought you could make the $50 parts that likely cost $25 to make for $12 bucks.then you could make some money..but it is likely it is a $100k special machine doing the making, not a $4,000 bench machine...so it will likely take $300 worth of time to make the part you can sell for 50 bucks..

Actually spending $300 worth of time makes sense. For my CNC usages, I don't have high throughput of customers. It's basically a special expensive custom order for small amount of customers and it needs to be built and needs to be perfect. Making profit is not the question, all that matters is can the design and job be completed. If a $4,000 bench CNC with some love and time can make the part, thats great not in a hurry to make thousands pieces only need to make just one piece lol. If business is great I would then consider getting the million dollar CNCs but I have no time dreaming.
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The whole thing seems a bit gimmicky to me, but I'm open to being convinced otherwise. If these were soo good and could be manufactured for $25 why are newest power hungry GPUs not using them? (they use sintered sponge like copper material).

Personally I'd be very interested in seeing some research that shows if there is any difference between these difficult to machine conventionally fins (100micron fins, 300 micron spacing) and let's say 500 micron fins with 1mm spacing. Yes, very thin fins have larger surface area, but at which point the bottle neck becomes conduction of heat up from the bottom into those fins?

I agree I am also interested in this research. I think there is an optimal fin count and gap needed and anything more precise is just over kill. I just seen today 0.6mm fin gaps used in water blocks for the RTX 3090 GPUs which was released for $1,500 one or two years ago. Die hard gamers who have these expensive GPUs are buying these water blocks and getting good cooling performance. So this means going ultra small like 0.2mm fin gaps not really needed, but if customer wants it, I simply spend the $50.

My customer used to make very small end mills, 0.04 mm, and we sent them off to the factory for a test run, and they worked just fine.

There is no particular problem milling very small features (my customer, lot of edm electrodes) and very long reach.
It´s just slow.

Thanks for the reply.

You can please discuss more on the process. I will now aim for a larger 0.6mm channel milled gaps since this seems to be the optimal size for water flow and cooling performance. Doable with the PM-25mv?
Seems like our German CNC thinkers who likes to make custom CPU/GPU water blocks have already done this great level of precision work 10 years ago using a BF-20 Vario converted Mill to CNC which is identical to the PM-25.

I am completely astounded to the level of work and detail done here:

He was using a precision VHM sawblade with a cutting width of 0.3mm. Same process as how many have advised me on doing so.

You're astounded that a guy cut some slots ? Wait until you see one of us drill a hole !


That picture above was done using a high precision 0.3mm saw blade on a $3,500 European "Optimum BF-20 Vario" benchtop mill (close cousin if not identical to the American version "PM-25mv") converted to a CNC.
I asked him on YouTube and he replied 16 hours ago about his mill:

high precision micro fins on BF-20 Vario mill.jpg

Lets be honest here, that is quite amazing since everyone originally said it was impossible lol :ROFLMAO:.
God I love it when they say it's impossible but always some German precision machinists somehow made it possible cheaply (10 years ago)...
Every machinists on this thread should buy that man a cold beer :cheers: because he did a criss-cross cuts like a square waffle 🧇 too.

Not to mention, his criss-cross saw-cut 3D micro-fin slots achievement brings more copper surface area to transfer heat away into the water flow compared to the industry's best single cut micro fins $50 Optimus Gen2 cold plates (which I thought was overkill until I saw the criss-cross stuff).

EmGo, If this is nothing for you, man I gotta see what kind of high precision slot cutting action you can put up your sleeves with a $3,500 mill, I could learn a thing or two but right now this is cool stuff for me, so much insane water cooled projects I could ponder about.

Forgot to mention, his youtube video shows him doing a newer version of it which he posted 3 days ago, from the looks of it, seems like he has improved and using smaller saw blades creating 0.2mm micro fin gaps. The translated YouTube title "0.2mm saw blade - slot 2.6mm deep". Seriously should buy this man a beer, using 0.2mm blades (same as to the $50 Optimus Gen2 cold plates). :cheers:

Who bets he did a criss-cross micro fins with 0.2mm saw blade?...

The photo of his criss-cross water block micro fin cut using 0.3mm saw blades was done 10 years ago which I think the Optimus Gen2 cold plates did not exist at that time:
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Lets be honest here, that is quite amazing since everyone originally said it was impossible lol :ROFLMAO:.
No one said it was impossible to cut with a slitting saw. Many of us do things like that on a regular basis, and yes, I have slitting saws thinner than that, which I use in Titanium. IIRC, what people said was impossible was cutting it with an endmill, and doing it in small quantities for cheaper than what you can buy it for.
Lets be honest here, that is quite amazing since everyone originally said it was impossible lol :ROFLMAO:.
Nobody said it was impossible. Nobody but you is amazed. They said what YOU wanted to do - use an end mill in a $50 homemade pos - was impossible. People described several different ways to accomplish this job, without hauling their dick out and stroking it.

If you just put "circle jerk" in the title there would not have been as much confusion.
Hi rajhlinux:
A detail you may wish to consider:
Some grades of copper are much easier to cut than others.
Probably the best is C145 tellurium copper (Telco) which is considered to be "free machining".
You can buy it from McMaster Carr.

Since you are already corresponding with that German machinist, you should ask him what grade of copper he is using.
If it's indeed Telco, then there's no real magic there...if, on the other hand he's using C101 or C 110, then call me officially impressed.
BTW, the thermal and electrical conductivity of Telco is not quite as good as C101, but it's pretty darn close.


Not overwhelmed with the design. Liquid cooling you want the liquid to slow down and wander, the square/grid is current and eddys, nothing between.
How do you get patent on that heat sink design? Digikey has hundreds to choose from similar.

Show me a spiral and wave to increase waters time over greatest area of copper.
I was recently reading some papers on heatsink design (I wanted a passive cooler for a project). There is quite a lot of research out there on this stuff and the gaps/heights are not that obvious. There are a few calculators to design optimised cooling for various designs and some of those are free. Some of the factors are totally unrelated to the fins themselves as well. Interesting stuff. Just google a bit for the various papers (lots are referencing air transfer, but I think you can extrapolate to liquid cooling as well as it's a parameter)
Use a diamond and this laser to cut it with:

j/k that laser is truly kick a** for all sorts of things. Four-inch cut depth without taper—also, no heat damage.
Hi All:
I understand the desire to help the OP to the best outcome we can, and part of that is to offer him design alternatives to the decisions he's made.
But what he's hoping for is advice on making the design he's already chosen, not to find the best possible design.

A corollary to that is that we are invoking processes he couldn't possibly get near for the capital he hopes to spend.

So if we get back to what the OP intends:
We've decided a slitting saw is going to work better than an endmill for what he's trying to make.
I've invoked the possibility of picking an alloy that's easiest to machine.
We've decided how this thing should be fixtured...standing up on a plate.
The OP has found someone who's shown it is possible on a cheapo crap machine, so that's put to bed too.

How much or little money he's going to make, how ideal the design is or not, how elaborate his fixturing has to be to make a million a month...it's all kinda irrelevant for this conversation IMO.


Hi All:
I understand the desire to help the OP to the best outcome we can, and part of that is to offer him design alternatives to the decisions he's made.
But what he's hoping for is advice on making the design he's already chosen, not to find the best possible design.
How do you know the OP isn't a woman, never intends to make anything and just wants us to listen to her problems without judgement?