I've been a machinist for 20 years now. I went to school for engineering and I used to be a TA for solidworks. Early on in school I designed a dobsonian telescope armature on solidworks. My teacher looked at the finished product and told me my model looked sweet, but then he handed me an old McMastercar catalog and told me to price out the cost of material on the telescope. Material costs came to $2,500. He told me to go back to the drawing board and consider purchased parts from McMastercar as well as minimizing the cost by designing with stock in mind. I redesigned that same telescope for under $250.
Haha yay nice! My machining experience was from my Ph.D. where we used manual machines to make parts for our physics experiments. The student shop had a very laissez-faire attitude, and I made a lot of parts for personal telescopes that are still in service :)
Talking about inefficiencies, reminds me of a story my grandfather has from his time in a machine shop, like 65 years ago. Big wigs from sales came down and told them they needed something like a 4" x 4" square that was flat and parallel to within something like 2 tenths, all over. So, they set up, and spend all day carefully measuring and working on this thing. Finally done, and it is taken up to the guys who requested it. Machinist asks what they needed it for, and they were using it as an anvil to install wire crimps. Machinist almost lost his mind, and when he got pissed and asked why they demanded such tolerances for something so stupid, the guy said, "Well, I heard you guys work in tenths?"
That's why you need a sales rep. They take the specifications from the customers and give them to the engineers. They have people skills. They are good at dealing with people.
I work at a startup and there are so many engineers that need to watch this. Thank you for taking the time to lay this out so laypeople can really see the impact of seemingly-simple design decisions.
I'm IT but some fields tangentially involve machining, and once I learned there's a specific field of lawyer-engineer-accountants optimizing products for cost and legislation, that reinforced my belief that designers are extremely concerned with cost and production efficiency. Cue the real world showing me that many first drafts come into production and even I could spot the wastefulness of their approach. Myself got in a few projects for being one of the few being very concerned about cost-effectiveness and efficiency (devising a hardened battery powered controller prototype that does a ton of stuff but just 2KB of RAM). Price point for lab prototype was hard set at $250 in hopes to get that streamlined by another engineer into a sub-100 device. Was mostly involved in code but I had considerations for the physical part and engineering told my concerns were appreciated. A separate department did a similar device at over 10x budget, less features, less stable, and couldn't endure external environments. But was better venture capital eye candy.
@@Mordecrox If you go into DevOps/SRE/whatever the new buzzword is, you'll find it's mostly about cost efficiencies. My parents get shocked at how wildly asynchronous my schedule is, but I remind them that my first "big" project that got me noticed by all the bigwigs at my startup was one which saved year-over-year the equivalent of my salary, and I regularly get those kinds of assignments because I like improving performance efficiency and reducing resource waste, which is almost always going to lead to cost savings, so the company wants to keep me around to tidy up over-provisioned things
Tip as a start up- hire a tenured machinist to work in your engineering department, pay them for design review, just under project lead in hierarchy but separate command chain- they will save you their cost a dozen times over rejecting unnecessarily tight tolerances, non-standard fasteners, and appropriate mill stock. If you’re working with just one or two engineers it’s probably worth adding the time having engineers reference lists themselves or ask your machinists, but by the time you can give a machinist even 10 hours of work, _contract them fulltime._ Most of them have the knowledge to design accessory parts if you can’t afford to have them waiting for something to do
Oh and don’t overwork your machinist consult- you _might_ be paying them more than they made in the shop, and it’s easy to believe they aren’t doing real work, but honestly they’re doing you a favor and you should treat them like it- if it’s 3 pm and it doesn’t look like people are going to give them something to check, let them go home- you can always have them approve a design from home if its still during their office hours. If you make them work after hours without generous praise and compensation or harass them for idle time between consults, they WILL leave you and go back to the shop, they’d prefer to be there anyway.
As a Jack-Of-All-Trades anomaly in my facility that personally handles design prototyping & 3D printing, and interfaces directly with our CNC department, I cannot overstate how much value I find in your videos. I pride myself in how much I try to account for design choices that make their lives easier, but you consistently point out things I would never consider and they haven't yet bothered to complain about to me. Thank you sincerely for making these. I really need to direct more of our full-time engineers this way.... The CNC guys also complain to me about so many other of our "mechanical" engineers..
@@SchizSchool I'm getting thrown at one. Basically I was sweeping one day and I watched a dude on a manual machine and they decided "hey you're pretty good at this" when they heard that I had started learning a little from him. So I went from "you'll probably program laser cutters" to "you're being primed to learn how to plan/program operations on all machines for all parts and also be the one to politely email engineers back with criticisms on their designs." Small company stuff I guess.
@@november382 Spoken like a fellow generalist: "No idea man" I learned so much more from working in metal manufacturing than I did working under doctorate mechanical engineers. Seeing how the sausage is made and being able to talk to people who have been running press brakes and turret punches for about as long as I've been alive is fascinating. Especially when one of two types of parts got ordered: If it was a design made by a clearly nascent engineer, they would complain about how time consuming and expensive it was going to be for nearly no benefit to the customer. Some companies would accept alterations to make their parts cheaper, others didn't care about redesigns and just wanted them as-is. But sometimes the designs that hit the shop floor were incredibly elegant, clearly made by someone who deeply understood manufacturing principles and considered all the pitfalls manufacturing the part could run into. A n engineer that understands their part needs to be made in physical space out of real matter. We like those engineers
You did a good job explaining that I believe. I was an estimator at a fabrication shop and saw a lot of mistakes in design for fabrication. Often I would return quotes with two prices. One “as designed “ one as “improved for manufacturability”
This is an excellent video, definitely saving this to show some engineers I know. I’m a machinist and one thing I’ve seen that I like is a note saying stock surface acceptable. If you want to stay with nominal numbers but don’t want to pay for grip stock, make sure the machinist knows it’s fine if a surface is from factory. Aluminum extrusions are reasonably good in my experience on dimensions so odds are it will fall within standard tolerances anyway, you just have to be ok without a nice shiny machined finish.
Yeah my main client is fine with stock finish on both aluminum and CRS but they ask that I at least do a random orbital or something of the sort on the stock finish so that it looks better than from the mill. It has kind of blown my mind how generally on-size aluminum extrusion is for most common bar stock.
@@dumpsterdave3710 yeah the customer that I've seen that callout on usually asks for it to be scotch-brited or something. That is so much less work than actually milling a 4ft piece of aluminum down to 1/8in and it reflects in their price tag
@@cwmd7651 yeah, but the jabronies who call stock size acceptable also call their datum on CL. Always becomes a massive head ache with operators scrapping parts. I need a consistent profile to be able to do multi ops or things will just never line up right. IMO a drawing should guide a machinist in his material size selection, but rarely define it. Don't tell me how to do my job unless you know how to do it.
@@jonamr that's why it's stock surface acceptable, if you want to machine it down you can, but you also have the option to leave it as stock. If there's a feature with tight enough tolerances to be scrapped by variations in stock faces, that should be machined anyway.
My experience is very different from you guys, apparently. Nearly every piece of aluminum bar stock I get is quite far from square, and grossly oversized. I got some 4" by 3" bar the other day that was convex by .020 on every side and the corners were +0.050! Stainless and red metals are nearly always oversized from our supplier, and even our TGP is often under!
Things that make a machinist happy: Stuff that doesn't matter... +/- 1/16" (+/- 1.5mmm). Match drill and ream for dowel pins at assembly. Saw cut and mill finish ok on non-essential features.
Design engineer here. Came here to say exactly this. ISO dimensional tolerance (most stock shapes have an ISO standard). If it’s not an ISO shape just check McMaster, they’re pretty good about putting typical tolerances on their stocks.
Adam, I learned an exception or addition to your information. A long time ago when I just started my business I bought 8 and 10 mm aluminium sheet to build a housing for a machine I designed. It came in bowed like banana's. I called the vendor who showed me the specification on straightness for the supplied material. It was in spec although unusable for my needs. They understood and collected the bowed material or great service. He also advised me to buy stress relieved cast and milled aluminium plate or tooling plate in an EN AW 5083 alloy. This stuff is straight, really close to the nominal with (+/-0,01 mm) and has a beautiful finish (protected with a foil for shipping). I never went back. Although this material is more expensive I save a lot of work when I design parts to a nominal size because a lot of the times I don't have to machine into the thickness of the material. Mills wonderful and can be anodized too. This is why I prefer to buy nominal sized material or maybe this is a tip too. Thank you for sharing your wast knowledge with us. And I do liked the selfmade guns. Not because of their function but the quality you made them to be. Best! Job
Excellent content. I learned design from several crabby old machinists that dearly loved showing the “college boy” how things are really done. Figure out how you are going to build it as you are designing. If you have some “stupid” design element you need to be able to defend it to the machinist. If not they will make you cry.
Very well explained. A lot of engineers could take notes. I think across America way more engineers have no idea how machining works as opposed to engineers that do. I don't expect engineers to be 30 year tool and die experts, but I do expect some common understanding that we are not making things with magic xerox copier machines.
@@Iceberg86300 This - I work at a company that rents office space from a machine shop that produces our parts, and its incredibly valuable to be able to just go and ask the people that make the parts "Hey, is this going to work?"
@@banaana1234not in the US but the last place I worked outsourced an awful lot but also had an onsite machine shop. Now when it wasn't prototyping work the internal shop was almost "cost is irrelevant" (precision waveguides, resonance chambers, antenna arrays etc) but even with a not inconsiderable amount of machining experience it's very useful to just to be able to pop across the building and talk to people who do that shit every day.
Nobody knows how machining works anymore. I recently got a RFQ for a trapezoid made of ABS... made using FDM! A stupid half-inch-thick plastic trapezoid with no holes or other features and tolerances of .005! The quote said "please try to return by Thursday." I sent it back saying I could have the whole part made in 20 minutes with a band saw and a Bridgeport if they want to change the requirements.
I knew a guy that had just purchased a brand new cnc mill as a garage hobby machine and i offered to help him learn to run the thing by coming to my shop to look at how i run production and structure my programs, set my vice stops, etc. its a production shop so its set up for the products i make (which is similar to what he has in mind for stuff he wants to make). He never had time to come visit my shop and eventually started to beg me to come help him run his part he designed at his shop. I kept saying you need to come visit a real shop once because i knew he didn't understand the intricacies of parts design and how that translates to manufacturing process. Everything i ended up going to help him and it was the most frustrating thing ive ever done. None of his tools were organized so ended up looking for hours to find simple things like a socket to tighten his vices to the table, or a 1/8 hex, etc. Then his design was filled with chamfers and inside corner radius's of different sizes that stepped down going into pockets. Plus he read the machine had 14" of travel so his part (a transmission adapter plate for a rock crawler) was like 13.750". So it took precision measuring just to mount the vices so the stock would fit into the work envelope of the machine, and we had to eliminate tool paths and hog material on the first pass just so it could be machined. To top it off, he was a business owner and had his mill in a back building at his place of business. So he would constantly walk away in the middle of me trying to teach him, which turned my 1 day of helping him; into a full week ordeal of me driving an hour to his shop to show him 5 minutes of lesson and 30 minutes of waiting for him to come back; and he would not stay late to do his "hobby machine" so ar 5:00 when his business closed he went home. "Promised his wife 10 years ago he would never come home late." Like dude she knows you just purchased this machine and a professional is donating you his time, give him an ounce of respect and stay late one time so he doesn't have to spend days traveling hours and getting home late for your a**" I did the entire front half for him. Took all week and because the giant piece of stock we only had one; and because my skill i nailed it. Working back and forth with fusion, i ruffed it large and walked it in so could work out tool blending on the extra thickness's and made it perfect. I didn't just sit idle while he would walk away i was meticulously setting up the grand lesson of "should have paid attention." Cause in the end, I had donated him an entire work week of my time and we only had completed the first half. So he just had to do the back side and it was done! Lol. I even helped him flip and mount it so he gad best chances of success. I'm pretty sure he was never able to complete that part and ended up selling the machine because he thought you just showed the machine a picture and it magically created it. He was the type that because he owned his own business he looked down on anyone else, and i could constantly feel him looking down on me like he thought being a machinist was pointless because the machine does "all the work!" I clearly own my own business and am more than the machinist, im also the webpage designer, and create the advertising, etc (sole proprietor); or i wouldn't have been able to donate my time.
The point of the story is people think Machining is like simple work. When in reality it's very complex and takes years to gain enough experience to consider yourself proficient. Designing a part and manufacture your design requires more than just drawing up a design with holes you want the thing to mount to. It requires physics, art, math, and deep levels of engineering. You have to be willing to use finesse, have patience, quadruple check everything and think deeply. Or you'll likely fail.
I hope YOU learned something about troubleshooting HIS process. If the thinking isn’t coming out right don’t fix the thoughts, fix the thinker. This dude thrives on getting people to pick up his slack.
@@flyingmonkey3822 That was exactly it. He just wanted someone to run that part for him and had no interest in actually learning the trade. I really wanted to help him learn too, I really tried to teach him everything I could. ... But yes I did learn a lot from that venture.
Free help is rarely valued. A lot of people for some reason think if you're not charging them, then you're peers in this thing they have no experience with.
Thanks for sharing your knowledge and experiences. For me as an electronics engineer this is imensly precious. Its this kind of knowledge not many of us have which enables me to work with our mechanical department in a much smoother way. Thanks a lot Adam.
Thank you, sir! I'd love to see a similar video for heat treated part design - like whats tamper-clampable, hard milling vs grinding, etc.. Please go all out! :)
These lessons are vital to professionals, and also useful to home-gamers. The need for material to MAKE the part, in addition to the material IN the part. One observation from my experience - it can be very useful to weld sacrificial tabs on stock that wouldn't otherwise be practical to hold. We used to get Navy jobs, and they'd send us the material to use. Sometimes the material was just barely big enough for the part, and there was no practical way to hold it on my laser bed, so I'd tack weld it to a hunk of scrap big enough to sit comfortably on my bed slats. From that idea, I'd weld tabs on stuff I'd mill in my home shop. That allowed me to use my stock rack material more efficiently.
THANK YOU for just straight up talking about the real issues of cash flow and outlay for material vs. labor made on it vs. risk of failure. Protecting your business from extreme risk is always a paramount concern, as is opportunity cost and putting out a ton of money that only makes you a little bit back in return. That's bad business decision making, or at least something that should be minimized.
Adam please keep making these videos - engineers and designers need to know this. I appreciate everything you do, but this is paramount. Now if we could get designers to understand 3d prints are not perfect, we could really make some headway
This video was outstanding. Super informative and highlighted a few things I hadn’t considered. The previous video on chamfers and fillets was also great. I am surprised you received any negative feedback on that. I wouldn’t consider these to be esoteric topics at all. More like fundamentals that are easy to overlook. Keep up the good work.
I don’t think it was negative , the feedback was to not go into hardmilling or heat treat like I had proposed . Instead keeping the focus on cad design considerations for cheaper easier parts
@@adamthemachinist I would greatly appreciate a video about heat treatment, hardmilling, or any other topic not commonly addressed on RU-vid. Most professionals don't have your knack for communication!
@@adamthemachinistI would like to second tillytwo, maybe make a separate video after you have a few of these where you cover the more complicated topics for a whole set of videos all at once? That video may go all over the place; but it would also fill a spot in a niche that hasn't really been filled on youtube, and as a machinist who hasn't been working in industry for too long but wants to learn and expand beyond what I'm currently doing, it's exactly the kind of information I'm craving
I'm not a mechanical engineer, more of a software guy but I dabble in design from time to time. Always good to have this in mind and just sort of have some awareness and feel for it.
This whole series of videos is so great! Always wanted this kind of information, but no company wants to talk to you at length explaining all this. Thank you very much! Just watched probably 1.5hrs of these videos and now I have a different view on my parts. Just changed some details. Thank you very much!
As long as you are taking suggestions: can you make a video about overall design? Something like leaving parallel faces to grip, not having holes at weird angles if at all possible, having top faces be on the same plane, stuff like that. And maybe maybe there's some good information in not making a giant L-bracket out of a single piece, but splitting it up into two regular bars. Saving 5 minutes on assembly by spending 2 hours on mashing and so on...
As someone who does CAD review for manufacturing I love your content. The manufacturing perspective is often hard for junior and mid level engineers to understand and hearing a machists perspective is super helpful!
I didn't search for this video, but interesting concepts i never considered. Makes me appreciate the guys at the shop way more now. Have a good one dude!
@@adamthemachinist personally I’d love to hear your thoughts on heat treating and micro milling. Of course things like holes making etc are welcome too. I really enjoyed your older stuff like 3d printing part fixtures for precision measurements or your construction paper mockups of what’s happening in a cut as well. It was all great stuff
This is the third video i've watched just kind of absorbing your content. I just saw your account name and clicked. I'm not one for compliments but you're giving yourself a disservice calling yourself a machinist. If even 10% of the parts i'm told to make, were designed by someone with as much forethought as you my life would be so much easier and their life would be a lot cheaper as well. I wish i worked with a few more guys like you. Cant wait to catch a few more vids of yours
Hey Adam! Thanks for posting your video - great info. The general info is probably more accessible but it is cool to hear the really in depth/esoteric stuff every now and again. Keep it up!
We used to build injection molds for John Deere....they dimensioned everything in metric but if you converted to inch most of the dimensions came out nominal inch sizes....seemed like a waste of time.
@@d6c10k4 So John Deere made it a size that easily converts to standard, and sells on both sides of the pond not just the US. just because it seems a waste to you, doesn't mean it doesn't make sense in the greater picture
These last couple of videos are great for engineers who haven't spent time on the manufacturing side. I'm going to send them to a few newer guys I know
Esoteric has its time and place, but I think in a video like this, it's not appropriate. This is just to give a quick overview. Then later he could do a video going into depth on one specific thing, which would also be interesting. I use videos like this as a reference, coming back to them occasionally when I'm working. If it were crammed full of esoteric stuff, that would reduce its usefulness.
Many good points in this video. I'm a mechanical engineer by trade and a hobby machinist. For a lot of the stuff we make it is perfectly acceptable to have a millscale finish on the thickness. When thats the case we call out for instance PL25 on the drawing, and the machinist knows what ever finish and thickness the 25mm plate has, that is acceptable. One thing also to consider is some materials are most common as round stock, while others are most common as plate stock. In other words avoid making flat bar out of round bar when a similar grade is avilable as flat bar or plate, and vice versa.
Hello Adam from Australia. Thank you for reinforcing and strengthening my own thoughts. It is always good to connect with like-minded people. Just helps maintain our sanity. Cheers.
Great to see some more videos and see you share your knowledge. I just watched the radius and chamfer video and then this one comes up as well👍. I think you communicate it very clear. Working with tolerances and the difference between accuracy and precision would be also an interesting topic it would love to see.
Another piece of gold to show customers thank you! I thin the advice on keeping it simple and easy for non machinist is great for this series and I look very much forward to more! However nothing beats your very esoteric content that’s my favorite keep it coming too!
Fantastic content. Nice to see someone thinking this way. Another option to maximize value is when a design has large through-machined features and sufficient quantity to warrant a fixture. I like to make fixture to hold internal on through holes, with the fixture below the final machined thickness. I fully machine one side except for outside contours, where I leave perhaps .2mm. This lets me chamfer even though it’s oversized. Then it goes onto the fixture that holds on internal through holes and I can machine that side, finishing with an outer contour that brings the whole part to final size. I can usually hold +-.01mm this way and get a 25mm part from 1” (25.4mm) stock.
I have no idea if my previous comment served as partial inspiration for this, but this is exactly the sort of thing I was asking for. I just wasn't asking for it SPECIFICALLY because I didn't know what I didn't know. More of this across-the-isle stuff would be helpful indeed.
This is worth solid gold in the knowledge it provides to engineers and designers like myself to be able to understand and design based off the manufacturing process. Keep up the great work.
All great info peoples! I learned this the hard way, but grateful for my journey. This is what design for manufacturing is. When I first started as a freelance product designer I was unaware of all this. When work got slow I ended up working at a machine shop to keep paying my bills, I ended up staying at that shop for 5 years. I learned from the bottom up, topping of way oil, to setups, programming, material ordering.. I learned so much by hearing the inside scoop from other machinist, seeing setups and I was very lucky and got to run my freelance design business out of that shop, it was a win/win for both of us as the shop made the prototypes and parts.
Excellent video! As a design engineer, there are so many decisions left solely for you to decide. Having a deep understanding of how these decisions affect others down the line is crucial. Love the video series, please continue making these videos.
Im a design engineer who moced from plastic tooling to capital equipment. Im the 4th employee at a start-up, but i happen to a considerable amount of my own machining. I give alot of credit to people like yourself and the toolmakers tbat trained me for my knowledge
When a machinist often deals with customers who want flimsy thin parts, then the machinist needs a vacuum table. I would recommend that everybody who is in this predicament looks at the Witte Vac-mat system
Some rock solid tips right there, and you explained really well! Milling thin material further down to finish size must be a real treat, I feel you. I worked with sheet metal and it could warp and form bistable areas just from grinding a weld down too aggressively.
Good information. I am retired now, but in my many years of die casting tooling and product design I found that many of the younger generation of engineers paid little attention to or had no concept of designing for manufacturing. This was especially true in a casting environment where undercuts are the enemy and secondary machining operations are cost prohibitive.
I've really enjoyed these manufacturing/manufacturability videos. I'm neither a designer, or CNC operator, but I have a lathe and mill in my garage and there are some good tips in here for manual machines too.
Loving this series of videos. You did a fantastic job explaining everything! I can now imagine much more clearly how my part might be manufactured one day :)
Brantley Dunn and very practical a lot of people need to understand these things and most people don't have a clue I've been undersizing my parts forever so we can get them out of standard material and then I get complaints why is this such a funny size oh well great job as usual brilliant service to the community
Thank you for these videos, they've been really interesting. I don't know if you'd be interested/have the time, but it would be really cool to see an advanced or more esoteric version of these videos once you have a nice array of basics. I can't wait for the next release
Great insight. I design automated machinery-custom one-off machines-so the quantity requirements of each part are low. Oh, the stories I could tell regarding material issues. It is also challenging to know what type of machine the parts will be made on. As a designer, I am not allotted the time to chase down all the details to make a good decision. The machine progress payments are made based on milestones, and completion of engineering is one of those milestones. The incentive for positive cash flow is powerful.
go esoteric please :) Although practical is good as well, this sort of thing is really good. As a mechanical engineer I see so many examples of engineers who have no idea at how manufacturing actually works or how to design to make parts better/cheaper/easier. One thing that would be good to go into is how to apply dimensions, GD&T etc that makes sense without getting ridiculous. There are a lot of lazy designers out there who could learn a few things. It would also be nice to see a bit on the importance of the relationship between engineering and manufacturing (particularly external suppliers). I hear a lot of complaining from both sides and that really doesn't help anything.
Holes and fasteners indeed. Having to make 4 different thread sizes and 3 different reamed holes in the same part is one of my bigger frustrations. Most times it can be consolidated to less. And also keeping consistency in a project would be ever so very nice. Stick to one size reamed holes and don't switch 'em up unless you have to. Just today I had to set up the same clearance holes for a screw, but the holes were designed with different clearances. And this particular customer want the parts as designed. So 2 different drill sizes for what amounts to the same effing hole.
Thank you, Adam, superb explanation! The information about pre-milled stock was particularly useful. One technical point on the video production: watch your sound levels in the edit. You're working out at a (guesstimated) 8-12dB lower than normal for RU-vid, and there's one inserted comment that's quite a bit lower still. You need to keep speech like this peaking to around 4-8dB below 100% (it's what the RU-vid audio algorithm expects), and adjust any/every inserted speech clip so it matches everything else. As I said, you're probably 16-20dB below 100%, which is rather a lot. Otherwise people have to jump for the volume control to turn down the adverts! RU-vid has a lot of technical docs on what they expect, but that's the simple version! I both enjoyed your content and style and have subscribed, so please keep it up :-)
As an engineer, these videos are great because they're informative, short, and are constructive criticism which partially is why some engineers turn off their brains when machinists offer feedback
Massively appreciate the tips; I don't do a lot of high-precision die stuff as I design mostly medium steel weldments/billet aluminum/printed plastic, but your advice is nevertheless invaluable. I only got to run 3 axis NC in college so my manufacturing knowledge has a pretty big 4-axis-and-up shaped hole that I am slowly filling in with your videos. Thank you!
Cnc operator since I was 16, my dad let me work in his factory and I grew in love with CAD. There is a huge difference between someone that truly understands a craft career vs someone that is working for a paycheck.
Nice work, covers the topic pretty well. One other thing I get all to often is some part that get waterjet out of 32mm plate for example but needs to be thicknessed to 30mm. It is now practically very difficult to hold onto and access the entire surface. What's much better to do Is waterjet a bounding box for the parts which you can hold in a Vice and cut to size, then waterjet the finished parts out of that. I have also started a database at work with the part# and the stock format and dimensions that include the grip stock I want so when the boss man want to order stock he can just search that rather than Me opening the File in Fusion and seeing what stock I had used last time
