The TRUE COST of CNC machining!
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- เผยแพร่เมื่อ 19 พ.ค. 2024
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How much does it cost to make a CNC machined part? The answer depends on a number of variables like the material type, part quantity, dimensional tolerances, lead time, and surface finish. We demonstrate this using the two shock bottom brackets we CNC machined for the landing gear on the DarkAero 1 prototype. They were made in house on our Tormach from 7075-T6 aluminum. Quoting tools from Xometry offer a quick and easy way to see the cost of machining these parts if we were to outsource them. We uploaded a 3D CAD file of the shock bottom bracket to Xometry and then looked at the instant quote numbers to see where the cost might land in production.
Links to tools we use for CNC machining:
Tool Cart - amzn.to/3owW9ui
Anti-Fatigue Mat - amzn.to/3q6y12c
Gear Drawer - amzn.to/3nvTAaL
Torque Wrench - amzn.to/2LwFPev
DarkAero 1 Aircraft - www.darkaero.com/aircraft
DarkAero Knowledge Base - www.darkaero.com/knowledge
DarkAero Apparel - www.darkaero.com/shop
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00:00 - Intro
00:36 - Machining
04:37 - Cost - วิทยาศาสตร์และเทคโนโลยี
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The saying in engineering goes: If you can't make it precise, make it adjustable. This video gives you a great insight into why there are so many parts in mass production that allow for adjustment. Assembling 100 parts on a wide tolerance margin and then turning some set screws to get everything to fit together properly makes a huge difference in cost.
Great video!
When it comes to interchangeability and form/fit/function thereal serial designer is on the button. Anything else can be left to hordes of batchelors🤣🥂
Except where compactness, strength, or weight are important. Adjustability compromises a lot.
@@appa609 which turns out to be in far fewer places then you'd think.
In an aircraft, weight is ALWAYS important. Every milligram matters.
Adjustability adds weight and complexity. Neither is desirable when it can be omitted by design.
I ran across your video by chance, and I enjoyed the demo... however, as a former CNC machinist/programmer I saw a few things during the machining process that could have sped up your process, as well as created a perfect bore through the part without having the chance of a mismatch. When working with aluminum, don't be afraid to hog out more material during roughing at a higher feedrate... it's the best material to machine (metal-wise) and rip through without loading your spindle torque and tool deflection. Many times you can cut your cycle time in half by bumping up the D.O.C. along with a slight increase in feedrate and it will throw a better chip (both drilling and milling). Also, if you have access to a boring head, I'd suggest utilizing it to finish your thru bore if it requires tighter tolerances on diameter and concentricity... it will give you a consistent microfinish while holding your tight tolerances and it only takes 1 operation to finish. It also gives you the option to use an arbor fixture for securing the part while finishing the outer profile. Just some tips from an old machinist and a new subscriber!
Do you have experience machining inconel 718
@@eatablellama6581 Grinding, yes. Down to a couple of tenths. Pretty much the only material we used (gas turbines). Not a big deal for someone that knows their way around a finish grinder. Ran a multi-axis CNC Bryant, Brown & Sharp, I.D, O.D, you name it. Fun times at Pratt & Whitney, Lycoming, Sikorsky Aircraft and Honeywell. I miss it :-(
If you just made all that up then that was brilliant because i believed every word
@@brianbailey462 Nope, not made up... just speaking from experience!
@@nerfburger1511 well just know some folks in this world, like me for example, really appreciate what people like you do. Innovators, inventors, and people who make things.
33 years as a manufacturing engineer in Aerospace......and I can only dream of design engineers understanding what you just demonstrated, and we're just talking about the basics here. very well explained guys.
You are absolutely correct sir whatmost design engineers understand about making what they design you could fit in a thimble. I worked with a guy that had a story about this young collage grad Engineer applying for a job at Kearney & Trecker Manufacturing in Milwaukee, they made machine tools, back in the early 60's.
Old man Trecker was showing the young kid through the shop, from one end to the other. When they were done my buddy heard Old man Trecker (as he referred to him) tell the young kid you can start tomorrow at 7am. we work 10 hour shifts to 5:30pm. OH and bring a pair of coveralls. Coveralls said the kid inquisitively. Yes son said Mr Trecker you going to know every phase of maturing and why every hole Nube or flat is in every casting in every machine we make before you put a pencil to a piece of paper.
They always think if it works on Paper it has to work on a Machine. I have seen some Cocky Engineers get really humbled by Peasant Machinist.
I’m the lead designer for my high school robotics team and my number one problem with my team is that they don’t understand DFM.
I've found it's pretty easy to tell within a short time of looking at a blueprint, whether or not the engineer has any manufacturing experience. Unfortunately, the answer is usually NO. One particular part that I'll never forget was a hinge, machined out of billet aluminum...for the 'galley' door on a large commercial aircraft. Yes, the galley, where the flight attendants keep the snacks, etc. This included drilling the hinge pin hole (about .125" diameter) something like 4" deep! The hinge was nothing special, looked like any other door hinge you'd get at Home Depot, but was machined out of aluminum.
Another part was the latch striker for the door, which had some ridiculous tolerance on the square shape on each end...+/- .0002" if I remember correctly! The part was probably 1.25" long, .375" diameter with a square cut on each end. The engineer had even dimensioned the points of the square with a tight tolerance (tight for what it is, maybe .005" total).
My first thought is that the design group should have sought out an existing hinge manufacturer to try to find standardized parts already in production, or at a minimum, have that manufacturer produce the hinge to the required criteria...which should have been reviewed by someone with actual manufacturing experience, to question the tight tolerances and explain how this would significantly increase the cost of the part.
And don't even get me started on the use of GD&T! I can't tell you how many times I've seen things like the flange face of a bushing called out to the bore with 'true position,' etc. The only conclusion I can make is that 'engineering' programs seem to be leaving out crucial parts of the process. A friend's brother was in college to become an engineer a few years ago, and I asked him if they ever mentioned 'design for manufacturing,' and he said, "No....what's that?"
As a mechanical engineer, I can understand why new engineers generally do not have a grasp on machining. The main focus in college is math, statics, dynamics and other engineering theories. We would be lucky to even have a few college courses on drawings, modelling, dimensioning, geometric tolerancing, and many other important subjects to creating a working drawing. As a result, most new engineers has never been exposed to design for manufacturability and not prepared for the real world when we work our first engineering job. I'm lucky that I went to aviation school and got my A&P license, so I have been exposed to the practical side of engineering. I also converted my personal end mill to a CNC machine, so I have exposure to working with metal fabrication. If you work in a larger company, there are other people available to show the new engineers the ropes. On the other hand, smaller companies do not have that option and the person has to learn on their own. Generally, this is where most of the problems occur. Without a good background in design and machining, most new engineers lack the understanding to create good design and drawings with the proper tolerancing.
I often see or hear machinists belittle engineers. The fact is, its not an easy job when you are only provided specs and have to design a part or complex series of part to perform a function. There are many ways to make the parts to meet the design spec. An experienced designer would know what parts need to be done based on previous designs or knowledge from years of designing. New engineers may have no idea what to even do and create parts that can't be manufactured. In our company, we not only focus on DFM, but also for testing. The part not only has to be machinable, but it has to be done so that it can be tested properly. We even do tolerance stackup studies on parts bolted together to make sure all the parts will fit or align properly. Smaller companies may not have that level of process control so the drawings are less than satisfactory.
Nobody is perfect. You have to ask yourself: if the shoe is on the other foot, would I be able to do the job? Are you able to complete the advanced science, engineering and mathematic course to earn an engineering degree? Can you design a product with only specs, model the parts, create the drawings, perform stress/thermal analysis and test the parts to make sure it meets the specs? Most people can't. If you add in a short development cycle, its not an easy task. From start to finish, some projects are less than a few months for developing an entire system. In some fields, you have to take an engineering test (EIT) and get a professional license after a few years in order to be certified to do the job. If its easy, everybody would be doing it.
I've seen my share of new cocky engineers. Usually, they get a dose of reality when we do a design review before drawings are released. The senior engineers do a good job at slapping them down and making them humbled in front of their bosses. The ones who are not cocky and willing to learn, we teach them the right way from the start so they have a better understanding. I prefer to have the new engineers do drawing revisions or tooling first to get an understanding, but in today's world, they are thrown into the fire right away. As a result, the drawings and designs are less than ideal, but we live in different times. In the old days, engineers do the engineering only. We had draftsmen to do the model or drawings. Now, engineers are expected to do everything from the design, CAD modelling, drawing creation and also thermal/structural finite element analysis. Its quite a task to do it in a few short months.
The worse part in today's world is if a new engineer is good, as soon as they get experience, they move to a new job with higher pay. We are left to train another new engineer over and over again. I can't wait to retire.
I randomly got this video in my feed, but one of the reasons I like to have a CNC is how many times I can screw up or change the part or scrap the whole idea and move to a differnt idea in prototyping. Material is cheap, screwing up on a design you had a shop make and had to redo is horrendous and it hurts, plus doing the work on your own makes you a better designer and have a better understanding of things, I'm fairly new to all of this but I figure 10 more years amid practice I'll be pretty decent
Yes. Building things on your own is the best option and Something everyone should do and try
You didn't get this randomly. TH-cam controls your mind/
Judging by this video, it'll be cheaper to buy one's own CNC machine for just a small project, than outsource.
Not since biden was elected steel went up 40 percent over night
@@GenghisKhan311 Source?
as a small CNC business i really appreciate how you broke this down so simply. nobody realizes the amount of time and effort that goes into making A "SIMPLE PART", let alone the amount of time it takes to get to a high level of manufacturing to produce parts of any size and complexity. This video helps shine a little light on it. thanks
I am so glad that you tube recommended me this video and this chanel
Ditto. Subbed
@@dirtboy896 Double ditto. Subbed hard.
Me too
Dude, fantastic work. I started out with a Tormach 770. Those Tormachs are a great way to get started .
If you look at this part, it's a perfect shape for an aluminum extrusion. If we talk mass production. The extrusion production be outsources cheap and easy. The part just needs minimal CNC treatment and less material is wasted.
I dont know if its possible for aluminium, but I saw parts like this weld together from pipe with laser cut and bent plate. If you need tolerances you still have some materiał left for machining.
Leave stock in the bore on the first side then finish the bore thru while finishing the second side. Eliminates any blend issues.
I'm surprised he did that. You never finish a hole from both sides. Even if the hole is split due to a slot, like the smaller hole there. For the best accuracy, must always finish a hole all the way through in one shot.
@@gredangeo well to be honest. These guys are soooo new. Shouldnt even put up videos. It shows people how little they know about precision machining. Hey they are really nice guys no doubt and im an asshole for saying anything. They'll do fine. Slow, but fine. Or not :) i want them to make bux. Its a great profession. I now have vf3 in my home art studio. After a few decades of operating programing designing and engineering.
@@nobody617 Makes me wonder what they consider a "high level of precision". To me that's .00005"
@@logannewman4532 normally maybe .0005 would be tight for me. Rarely do I have to go that tight. The tightest ive had to hit was .0002. kinda rediciulous but no big deal with good measuring device. St that tolerance temperature changes that pretty easily. I'm thinking those were for a press fit. Freezing the part to be inserted. This type tolerance is probably meant to add as little stress to the part after insertion. It's been so long I haven't thought bout it at all. Usually .001 is adequate. But you do want to do your bores and whatever else lines up all in one setup. I suppose if that hire these guys were doing isn't all that important, the way they did it must have been adequate, I just always use boring bar from one side of course. I can't remember if they mentioned any tolerances. I'm just use to making parts and assemblies that weigh 300+ pounds and spin 3600 rpm :) what I've done is nothing compared to what's done out there in the world. Amazing engineering and machining is done daily like it's nothing. I am nothing. I'm aware. :)
@@nobody617 One more zero. I occasionally have to hold half a tenth.
I'm an 8yr Navy vet, current engineering student, lifelong aviation enthusiast and maker.... It gives me genuine inspiration seeing you all do this.
JR, so happy to hear that! Thank you for following along! 🚀✅
Nice nice..
I am a human who works a job, no collage experience other than signing papers and bailing, but i like aviation & looking to be a pilot, and also i'm a maker enthusiast.
i just like making everything. I built a CNC router but i need to get a CNC mill if i want to do anything serious. i had a cnc machinist job but my boss was a dangerous erratic fool.
Anyway im interested because id like to open a shop and make stuff. building a plane is on the list of things to do.
@@darkshadowsx5949 There's a book called Flying on Your Own Wings. It would probably interest you. Amazon ~$25
I am also an 8yr Navy vet (Subs) and engineering student about to graduate this spring, what program are you in?
@@fisherholmsfly I always thought subs were cool. Air side though...not too many tow tractors on a sub haha. Mech ENG atm. You?
The true cost of CNC machining also includes the price of the machine and the cost of the labor involved in designing the part(s) in the first place.
The part usually needs to be designed by you regardless whether you do it in house or at a shop
If you're supplying all the CAD files ready-to-go to the CNC mfr/shop, why should there be any additional "design" costs?
@@oceanic8424 For when the designer, who's never run a mill before, doesn't think about fixturing.
@@oceanic8424 they are ready to go when they have the path files not only cad files
@@oceanic8424 Because sadly the computer nerds virtual world doesnt translate into the real world of machining. You can give me a print of what you want me to make but I have to design and build fixturing for it which costs time and money.
TH-cam algorithm brought me here and I am thankful. Thank you for sharing. You have no idea how much this means to us who knows little about machining costs.
Excellent video because it explains what you do in DarkAero I, in-house versus outsourcing and cost versus economy is scale. Can't applaud you enough.
Azzam, thank you and thank you for watching!
Cost analysis was really interesting, I started looking at this as 'weld two plates on a pipe 'but I was wrong :)
Exactly, TIG weld two aluminum tabs onto section of ally tubing, but might only be able to get beads on the outsides of the part... then there are the dimensional tolerances. Could still be possible, but might need to fabricate a jig to position and hold everything to specs during welding.
@@oceanic8424 how do you do if the I.D. of the pipe is not available at the right size? Remember, the tolerance was 0.001 inch, I think.
@@jtcmlt1 Bore it in a lathe
@@noahhastings6145 Okay. I have the tendency to think CNC every time that I hear lathe or mill, vertical or horizontal. I forget that they can also be manually operated.
It is just a clevis, could have left it square.
Very cool guys! The one thing you didn't mention that I would be very interested in a detailed description was how much did it cost you in total to do those two prototype parts and please break down in every area as if you were prototyping for a customer such as Part Design Cad Time (software used) , material cost , cutter path programming time (what software used), machining time for both parts , cad design time for soft jaws , machining time for same and inspection deburring ,finishing time as if you were delivering to a customer. I think most will be shocked by the high numbers of prototype development. This will show the true cost of developing these two parts.Thanks for sharing that site for instant quote as I will definitely use that to experiment with some of my cad files.
That's a great explanation of the costs associated with these parts. Also, the variables involved. Great video
Thanks!
thanks for doing these videos, I'm glad you don't overhype it and just show what's going on
I asked a 6 year CNC guy to face off a 4" piece of 1020 round bar . Then drill a 1" hole 2" deep in it, then drill a 1/8' hole in the side.
He did not drill the 1" hole deep enough. Broke the 1/8 bit in the side, welded it up to cover his mistake. And went too fast facing it off and left a poor finish. He said he was unable to use his CNC equipment, and did the best he could. BTW... The piece was discarded
The moral of the story, you may ask? The true cost of CNC machining is ...the creation of a workforce unable to do the simplest of jobs, with out the aid of a $100K+ computerized work station.
You absolutely right. Just because they can set up a part on cnc and push the button to make it go they think they're a machinist. The programmer is the one that says what tools to put in and programs speeds and feeds in the program. Unfortunately back around 2000 they dropped tariffs on stuff coming from China. The results were 3/4 of small machine shops went out of business. And no one persude or trained to machine because there were no jobs. I know of 2 machine shops now that are looking for workers and there isn't any.
Its funny, because I asked a guy to do a simple part that would have taken 10 minutes on any number of cnc machines in our facility and he spend half a day on it because he was too busy worrying about using manual machines for clout.
Stop with your nonsense.
Meanwhile Vietnamese and Mexicans taking the few jobs left here
@@JuanHernandez-ub3ez No.
Love the video! People might love it more if you, if not but a few times in the beginning, show more of the aircraft throughout each video. Help people keep the end in mind, the context for each part, and the big picture progress!
One tip to reduce the machining time (because those 3D profiling is really unnecessary on your part): Using MasterCAM as an example: Draw out 2D profiles of the part. Top and side. Machine the top using 2D tool paths. Flip it over, repeat. Then lay it on its side, and machine the sides.
The top and bottom machining would have established the roundness and the big bore in the middle. Then machining from the side would take care of the rest of the dimensions.
Machine TWO part per vise. Your video may be a demonstration but machining 2 parts would have seriously increased your efficiency especially if you want to mass produce it (but since your machine does not have an ATC, the point is moot)
If you have 3 vises on your machine (very common in a CNC environment) you will be able to machine top and bottom on vise 1, side A and side B on vise 2. And then you will be able to basically mass produce the thing. This is probably why making 100 costs so much less than making 2.
Try to produce more parts per cycle if you can. Reloading vises every 2 minutes is VERY tedious especially when you need to make lots of parts. a 40 minute cycle is much more relaxing. You can basically kick back and relax while the machine is doing its thing.
Which is why a ATC, even if it only has a limited number of slots, is so crucial in CNC.
Though honestly would have found a used VMC for very little money if I were going to play around with CNC... but making youtube videos with sponsorship from Tormach may not be easy if that were the case.
Well honestly this Tormach is a toy when speaking of mass production Machines.
I would machine it on 5 axis mill. All in one setup. From my experience I would say cycle time would be around 7 mins. If you would charge lets say £50 per hour of machining then it would give you ~£6 per part
@@Ddk90 The problem with a 5 axis is that you may not be able to put 3 vises side by side in a 5 axis, table may not be large enough, and such a setup wouldn't work for 5 axis anyways as the workpiece must swivel in various directions, and 3 vises gets in the way even if the machine is large enough. They only make sense for more complicated parts.
Otherwise for most routine machining, 3 axis assembly line setup makes sense if you are mass producing.
@@taiwanluthiers I don’t think you understood my comment. I meant that I would be able to program this part from block of aluminium and to finish it in one operation in one vice. That’s what I do on daily basis. One vice, one block of stock, press cycle start, after ~6mins you have completely finished part. Besides chamfers on one side but you would deburr it by hand 👍
eh, lets not be foolish here, production is a mindset, not a machine.@@sparklenebula6042
Personally I'd have made that from round bar using the 4th axis hold the stock horizontally. That way you can machine around all of the sides with the exception of the end, all without fixtures and having to keep setting up. It's way more accurate and I use it all the time. Then I'd part it off and hold it in the vice with some packing in the gap to clean up the end.
You'd do it in much less time and without needing any tooling.
This, taking 4 setups to make this is ridiculous. At most, 2. With clever 4th axis use, 1 setup. I've actually made plenty of parts like this before exactly that way.
I love your videos. I support you from Argentina. The country where you would never had a company like this one.
I've owned a CNC shop for nearly 40 years.
That part is two ops and flip it to remove the excess. Wheel cut the slot You could use two vices and get two parts off at every push of the green button.
Good tips, was thinking this while watching the video.. I can't remember every making a part with a witness mark like that on purpose. I'm sure they will learn more as they go.
@@texastad1989
Actually I want to ask you.... is it easy to make plastic mould in cnc machining
On a five axis it'd be one op plus a finish face. All critical dimension and geometry would be done in a single operation so it'd be as accurate as the machine is. A pair of parts like that would be $250-ish. A batch of 100 could get down to $30 each.
@@AndyRRR0791 lol, my thoughts exactly... I love 1 and done parts... either tab a non critical dim off and scotch wheel it off or just deck it on a tiny op 2.
I think simpleish parts with tight multi sided features is about 95% of the 5axis work i see
Thanks for watching! Having a bigger machine, more vices, and/or more axes would give options for fewer operations. We used four operations on our machine because we have limited depth of cut with the diameter tools we can fit in our tool holders.
Thank you. Excellent video. Concise, precise and Beautifully explained.
i needed this video, thank you !!! love how u guys r using a tormach
Excellent video. I'm curious about the clear enclosure on the Tormach. Is that custom, and if so, what are the pros and cons of the design? (We have a PCNC 1100 with just the front facing shield but are thinking about ways of improving both safety and coolant containment with a custom shield.)
Another informative & interesting video. Well done! How do your in-house machine time/costs compare to Xometry?
This is interesting, I personally wouldn’t touch the original tolerances, but as a mostly hobbyist fabricator I would charge around $150 for the 5 thou version. Which I would produce with a water jet and manual mill.
Curious. Knowing/expecting I'd be making many more, I'd at least built tooling to hold 2. Chuck the material for the 2 lowers, throw that in the mill while chucking 2 uppers in the other tool. Finish lowers #1 operation, pull the tooling, load the upper and run it's #1. While it's running, reorient or move over to #2 tooling for the lower.
I got an eye roll when I made 2 custom RC plane parts overnight and only charged $20.
Somtimes its about helping, not making money :)
Based on the wording of the comment I am presuming that you were the supplier here. That's quite generous of you. I am sure that customer will be coming back to you for future work. Feel free to drop your website address here 👍
@@oceanic8424 I made an overnight custom part for an expensive RC aircraft and only charged $20 for 4 hours of work. When I gave the customer the part, he thought I was way overcharging.
I'll not do that again.
@@user-qy9rg3nt2l Clearly, the customer was someone that knows next to nothing about manufacturing parts and could not appreciate what you had done. These are lessons learned.
👊👊👊
@@oceanic8424 Agreed 100%
I spent around 2200$ for my DIY CNC including all the tools (and that's really a lot). I randomly check how much some parts cost if we would outsource them. Now we can get all the material we need nearby the cost is super low for all the small parts we make ourself.
Now we're also converting a small mini lathe to CNC (and that will be completed within next week).
I would have ran it about the same but with a few exceptions. I would have installed an expanding plug in the lower half that was in the soft jaws to keep the bore round while tightened in the vice. I’d use vice handle with a torque setting for repeatability. I’d run the bore undersize first so I could measure and correct for shift because it’s not a perfect world. Real world in a good machine, .001 true position between bore halves. Need it closer and rounder?leave .003 stock and hone to size. 7075 was the best aluminum alloy choice for fast, accurate machining.
Also, it will be more expensive from a small shop versus a large one. Small shops don't keep much raw material on hand and don't get as good of prices on material as a volume shop can get. They can have older CNCs that aren't in the best condition, that makes hitting those +/- .001 - .0005 tolerances much harder to get.
When I was doing job costing, it was machine cost per hour, operator cost, tool cost, material costs divided by number of parts produced + bag and tag.
I had to explain to so many customers that were new to cnc prototypes that it doesnt matter if I make 2 or 20, roughly same total price. only difference was material cost, 2 parts in an hour or 20 parts in an hour, total hour cost /2 or total hour cost /20
This is the first time I see your channel and I am positively surprised. I work in the CNC department and I like your approach to work. Are aero parts always made entirely of a block of material, with no welding?
Dang, I had guessed that the parts where manufactured differently; one from a block and one from extrusion. If there were high quantity batches of parts I bet an extrusion could get those costs WAY down. It is crazy how just much money you can save when you spread out the cost of labor of the setup/programming over 100 parts instead of 2.
I know it is a late comment but if you have to make a bunch of these the part looks like it could be extruded, so get a long form of it and cut to size then do secondary machining for the side holes/profile then ream for precision. That would be the most economical way to make this part in bulk.
Nice but when making soft jaws you could just make it to the parts size and comp it till it drops in and no need to pick up another offset
anytime I machine 1 or 2 parts its time and material, for most jobs I mount 3 double lock vises for 6 to 12 parts at a time , for higher production make a fixture and remember for high abrasive material you may need diamond coated cutters
Great video, Wish i lived somewhere material was so cheap half the time i can't even get scrap stuff for that cheap.
The catch is you are still using shop time and wear/tear on your machines it does bring cost way down but can quickly add back up if you include design time.
moral of the story everyone should have 3d printers + CNC machines haha
We've had to do various one-off/prototype parts for aircraft manufacturers on a 6 metre, 6-axis mill. Some of the prices would make your eyes water for these, but on a production run it drops massively. Also to show how daft some companies are, we had to do a spare part for an aircraft that went out of production a few years back. When in production they were made 5 per billet (3m x 1m x 75mm billet) and cost around $20,000 for the 5 parts. They just wanted 1 part though even though they could have the other 4 for future spares. Paid full price for that 1 part. CNC machining is a funny world
Reminds me of when I needed a stepper motor to replace a piece of lab equipment. The previous generation had them available for $200 bucks. They didn't sell them for the new model. I found a company in china that could make them with a minimum order of 100. The cost? $2 each. Seriously. My boss said "but we dont need 100" and sent the equipment back to the manufacturer for repair. They charged us 2500 dollars and replaced the motor. In retrospect, I should have asked them if they could charge me for 100 and throw 90 of them in the trash. "They said they will sell us 10 for 400 dollars!" Hed probably have gone for it.
There are other costs you are not considering or did not mention, like the amortized cost of your machine. Most job shops will take on a fixed cost to an order to cover part of the expenditure for the machine that will be used. Again, like set up costs and tooling costs, this will be spread across the number of parts in the order. The more parts made, the cost per part drops. You have that cost in house as well, and you need to track it so you know when you have "paid for" your machine by spreading the purchase costs over a number of jobs. This also helps when considering the depreciation fo the machine for tax purposes. You can recoup some of your costs through tax savings if you keep track of things like this.
Most amortization schedule would be done one timeframe only ( x years) and not relevant to usage, unless you can demonstrate a real cycle based cost impediment which I doubt anyone would bother to calculate for manufacturing shop machinery.
Love the video! What program/software are you using? If there are any other programs out there anyone recommends for quoting feel free to comment. Thanks!
Without getting too in depth regarding cost with CNC machining, die casting and surface finishing, is there a way to roughly work these out to get within a good rough estimate category to initiate negotiations with a vendor when looking at their initial proposal which shows a breakdown of components?
When I worked at Boeing as a machinist they told us once that due to tolerances a 707 could vary 7 feet in overall length.
I ran an electronic tracer and had tolerances on two parallel surfaces over a 6" span of +0.0/-.005 on a titanium part refueling nozzle. Every part I made passed inspection.
Management came down on me once for making less parts than the first shift guy till I pointed to all his reject tags.
That shut them up. Lol
Perfectly explained. Thanks!
Seems like the best way to use xometry is to make low tolerance blanks that you can then 1 op to get the fit you need. Just sayin.
Good job, but one recommendation, you should profile the whole part depth in the previous op to avoid the blend/step line. Or try a large ball end mill profile if necessary.
Agreed! Thanks for watching and the feedback! 🙂
in my experience at a job shop, is 99% of the time we see +/- .005". but if the engineer specifically wants something to be like dead nuts, they will usually shoot us an email describing the importance of something and/or ofcourse using GD&T on the print. like if an engineer was like "this bolt hole pattern needs to be dead nuts with this o-ring groove' as the machinist we can understand that we dont have the best inspection tools but we can do this in one setup and be sure its accurate. so i think having good business comms is important
yeah, I ran a couple prototypes where we had to interface 2 OEM parts. At some point, it's just easier to go to the machinist and be like "this is the drawing, but they just need to fit" I could spend all day doing GD&T, but don't have the tools to verify they meet spec beyond my physical parts which act as a Go/No-Go.
@@RaphYkun yup! Makes our life easier too haha
Very nice, it’s nice to see something a little more challenging on a three axis machine.
Awesome video -super informative. Thanks for posting! :D
What kind of endmills are you using? Also software? If you use variable geometry endmills or high speeds and feeds with low feed per tooth with a trochoidal tool path your tormach could do it with less strain on the spindle/drive. Also I would suggest from personal usage that you should buy some short insert drills to define the initial shape of the bore in one stroke
Looks like this part can be done only in two operations (maybe first 2 from 4 isn`t necessary).
Thanks for your video and link for cost comparing!
Thanks for great video. Have you considered your time invested into machining the part on your own in workshop into the cost analysis? I mean often can happen that you think about how to make the part cheaper, not realizing that for example two hours of your time as an aerospace engineer is actually the cost of the part if you take the first offer available. For prototyping in this case of course. I have this kind of dilema often.
He only seemed to mention the cost of material... But then there is the machine and upkeep, the shop space, and time like you said. If its a hobby of yours then maybe its time well spent because you are enjoying yourself.. Thats worth a lot right there
it's insane what you guys are making! This is true insanity. I just love this.
How do you know where exactly to place the part in the clamp? IE: If you place the part 20mm to the left or right, how does it not cut/mill it out of spec? I love watching these but when I see pieces being flipped multiple times I often wonder how things aren't getting messed up. Almost like a jig where you could only put a piece in one way, that's almost what I am expecting to see. (sorry for the silly question)
FYI, the quantity of the parts on Xometry will autogenerate for more than 100. You have to select other and type in any quantity.
now i know not to outsource my pain in the ass parts, i was thinking about outsourcing 20 or so but thered be no profit when i sell em.
As much as it sucks, those small batch parts are what keep a lot of small shops and manual shops in business, because they're only a waste of time for big CNC shops- unless you're willing to pay the outrageous cost
Looking forward to the completion of the dark aero 1! Curious on the time involved on those small brackets to go through all the matching steps you have to do with your current CNC?
Bill, thanks for watching and the question! This part was around an hour for the CAM and then a few hours for the machining including making jaws. We are still learning CNC as we go along so probably takes us a little longer than most.
@@DarkAeroInc ... a "little" longer. Good one. You have a sense of humor.
Darkaero 2 with titanium parts like the sr71!! Is that a teaser for a supersonic kit?
I’m a CNC Machinist, my specialty is Swiss style machining. Our shop has plenty of 2 axis and 3 axis machining capabilities. Along with plenty of milling capabilities as well.
If you ever need some work, feel free to hit me up.
What are the odds this part will fit/function as planned? As with the rest of this project, I'm taking the "WILL" side. Great work!!!
Whether it will fit or not depends on your tolerances. If it's a part for your high end gear you can be sure the company that made the parts have their own standards, which also includes quality control. There are tools for that control: specially machined and "ground" calibrated parts - rectangular or oval in shape, for example. Oftentimes clients do their own quality control. So it all boils down to tolerances :) hope it answers your question!
@@viliusmarcinkevicius4747 Hi,dear friend,have contact information in the video th-cam.com/video/_SBkl3b2ZOs/w-d-xo.html
Quick question for you, I am in the process of creating a business model (super early idea stage) for a service similar to Xometry. What would you expect to pay for a metal (aluminum) Baby Yoda that is 3.5 inches tall if you wanted one really bad? Xometry says for DLMS (metal 3d print) it would be ~$950
Amazing video! Liked and subscribed. What about the cost and quality of the new service of pcbway of cnc machining?
Appreciate the time stamps!
Seeing your drilling op at 2 minutes, I gotta say you can increase your feeds and speeds. Looks like you have a Tormach pcnc 1100 which has a max spindle of 5140rpm.
Check out FSWizard, it’s a mobile app. You plug in your machines max spindle, tell it what tool you want speeds and feeds for, the coatings on them, length they’re sticking out, etc. For drilling with say a 3/8” standard hss drill in 7075, run that sucker around 270 surface foot and .0036 chip load. (2752rpm, 19.88ipm). That’ll also cut costs, especially after prototyping
th-cam.com/video/_SBkl3b2ZOs/w-d-xo.html
When I make fishing molds the vents are .0005" high. Sometimes .001 just isn't enough.
As someone who practically inherited a failing machine shop and ended up having to shut it down in 2015 due to being a young dumbshit that knew nothing outside of QC and being completely ignorant in running the business and making it grow- It's nice seeing that you guys are putting out information out there for people interested in manufacturing and giving out advice. Hope to see your planes in the skies of SoCal
That's awesome guys!. I really wanna learn this thing.
One cost US$400 while cost US$40, that your thumbnail said. As far as I notice, to make combustion engine parts high compression ratio need more steel rather than Aluminium 7075. I just don't get clear message which cheaper between CNC or die casting, just get idea that CNC is future 4.0 which need material lost. Btw I like this kind of video.
Set up and fixturing is the biggest expense on any multipart job. Optimizing tool paths and roughing is where the time is saved. Manual tool change vs automatic is a tenfold time savings. That pecking drill retraction speed and distance optimization could have saved you a lot of time, for example. I learned (taught myself) CNC when there were no CADCAM programs (IBM 386 days), only a calculator and a drawing. Machine and fixture rigidity and repeatability will save you a lot of time, money and frustration. Fun stuff. :D
Have you ever tried Plethora for CNC machining? They have a more robust uploader, and actually make parts themselves instead of further outsourcing
I would love to see a cost work up of this part redesigned in a 6000 series alloy and manufactured via welding two 2D profiled ears onto a piece of tubing. Even if the main bore needs to be reamed afterwards, it should cost about 20% of the fully CNC'd part you described.
Hi,dear friend,have contact information in the video th-cam.com/video/_SBkl3b2ZOs/w-d-xo.html
I think that would be cheaper, but maybe not as good a solution for an aircraft part. More inspection and failure points, reduced strength in the weld zone, and you'd probably have to bore the tubing out to get the fit they wanted. But if it were for a car? Yeah, switch it to plain carbon steel, make it out of tubing and some water jet cut ears and it would be way cheaper, stronger and more fatigue resistant than the aluminum part, and not much heavier.
Could you give us an approximated cost of how much it cost you to do those in house ?
I know that you said it just cost you the material, but it also cost you time and maybe maintenance on the machine ? Thank you for your video btw
once you take your part from datum to flip for next operation will it be accurate?
There's another way to have done this job, why not just rough And finish it from the one side and then go straight to the soft jaws? Also I might be mistaken but that end mill looks like it could have completed that hole to depth from 1 side, so there would have been no need to stress about it not lining up on the 2nd set up or if you picked the roughed hole up properly. I only saw 2 setups ... maybe 3 if you had to machine the slot with no radius in the corners. Also i see there are clearance holes on the side so thats another setup
Good quick review, but you need to consider machinery, consumables, labor, and repair costs rather than just how much the bulk material is.
Interesting comparison. Thanks.
Nice demonstration. Why you do have to manually flip the piece around for each ‘op’? Shouldn’t the machine be able to do that automatically as part of the process? And what happens to all the aluminum waste/cuttings? Can they be collected and recycled back into aluminum ingots for use in future jobs?
so what your saying is that i should get machining equipment and learn how to machine to replace the parts on my future farm equipment......
I APPROVE!
Thanks for that Video!.. keep it up!
Where do you get your steel stock? Any good suppliers you recommend? Thanks
I do cnc field service, rural machine shops dont have outside signs, farmers come in and thing they can get the part cheaper than john deere
Have to check if you commit to a batch of 1000 parts, will Xometry let you inspect the first few that come off the line....contract sticking points.
Not much of a cnc guy yet but I think its really cool. Planning on becomming a tig welder :)
Awesome video, the term you were looking for is concentricity btw !
Thank you and thanks for checking out the vid! 🙂 Correct, concentric it is what I was going for. Late nights at hangar and camera shyness got the best of me that day!
Do you guys still have a target date to fly in the spring?
Good content.
Do you guys bid on jobs somewhere? Is there a central dispatch for small cnc jobs somewhere? Whats the name of that site? Thanks
You could easily cut at least one of those machining operations.
Also, surface roughness does have quite a high importance when it comes to machining cost and also tolerance of the parts. In the example the +/- 0.025mm tolerance is kinda wasted with Ra 3,2 as they are somewhat linked and you can't produce accurate surface with poor surface roughness. Surface finish for these kind of tolerances should be close to Ra 1, that Ra 3,2 would be suitable for something like +/- 0.10 to 0.15mm.
Nice video, great info. Try quoting with fictiv, better and cheaper.
Out of curiosity, what would the same part cost if it was manufactured from generic extrusions and welded together?
Is that a retrofitted VMC? I noticed Z G00 retracted slow. I want to do it using Masso touch controls.
That's y I love my 5 axis herlme c400 so much... Doing all this in only 1 run and cut it off with a small saw blade for the cnc at the end. Part completely done after 18,5min runtime
How do you align the part correctly after you pick it? I'm just a random curious gawl. Not an engineer
Also I always wondered. Does the waste get recycled in any way?
hello good sir, your video gives me joy
As a manufacturer. We did business with some - (competition) of Xometry, but not Xometry itself, so I am curious how Xometry works. We noticed a significant price drop to the manufacturing side, so low to a point it wasnt even close to being profitable anymore. I tought, some prices where very unfair and its all on a take it or leave it bases... So we decided to - leave it.
I think those websites do a great job, but I also noticed a great risk. Because what if you invest a great deal in extra capacity and those website just drop the prices like no tomorrow and all that work just goes to low cost countries in eastern Europe or Asia.
I felt that - there was no benefit. - AND - I felt the risk to do a great deal of business with them is just to big. How do you feel about this?
I have been working as a quality engineer for many years now able to use cad design my own parts then moving on the cnc machining may I as a question can all cnc machines use cam to programme or would some require g codes ?
My question is, by jyst looking at the drawing how can we estimate machining cost without any software or aap?
Is there actually a very different machine/setup for tighter tolerances? Or does price mostly reflect a slower, more careful process, perhaps a better tool? I am also curious how often parts get scrapped in a big CNC corp like that.. is the higher cost reflecting expecting substantially more parts that fail to meet QA?
Hopefully you get enough volume that you can get a multi axis machine and custom fixturing, That were were its at. My previous employer is using robotics for pick an place and assembly and they were only 70 people.