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Mechanical engineer: how to work faster?
11

Mechanical engineer: how to work faster?

Mechanical engineer: how to work faster?

(OP)
I am a mechanical engineer in a wood sawmill company, I am designing various machines. I use solidworks for my design. The problem is this: I am not satisfied by the speed I design things. Here are some aspects I analyzed and noticed:

1. I always try to make the model as "full" as possible - including all bolts, chains, and anything else. This is essential for generating BOMs correctly, and also avoiding design mistakes due to things that were "imagined" differently than they really are. Any decrease in model detail would result in more mistakes (previous engineers, like 3-4 people have perfectly showed how not designing something leads to the need of fixing the final product with angular grinder in the workshop, making much more mess than use). I don't think I can save anything here.
2. I use all the productivity tools: keyboard shortcuts, best-practice design tools and strategies, PDM, fast hardware computer, two monitors, 3d mouse, I know the software deeply (including that I have passed several SW certificates). I don't think I can increase anything the speed here.
3. I have a fair amount of experience in the things I design - I don't have to spend too much time on the phone consulting the suppliers, or the machinery guys/welders to make the design better, and so on. I mean, I don't get stuck often during the design. I don't think I can do anything faster on this.
4. Of course, there are times when I have to do the research: check the solutions of the competitors, consult the suppliers about the things I haven't used before, perform FEA simulation, etc. Also, I sometimes have to explain things to the welders/machinery guys/assembly guys - about what have I designed and what is the intent of those solutions. But - obviously - I will never know everything, and so these communications will always be needed. I don't think I can rapidly save any time here.

Besides, I think I can say that I make fairly little amount of mistakes. I check, and I check, and then I check things again. I must admit I lose some time here (absolutely not significant amount of time, but it adds up a little), but design mistakes would make much, much longer to fix during the manufacturing process compared to the model, so I wouldn't like to risk the increased amount of the mistakes for winning a few hours on design checks.

That being said, I feel stuck in the situation. Even a fairly simple machines takes 1-2 weeks or more to design, and when I look at the finished model - and I can't believe it took that much time. I have no idea how can I make it faster.

If anybody here, the more experienced engineers, could share their productivity strategies, that would be great. I am pretty sure I can not win anything on the software level (as I said I think I can say I know Solidworks fairly well), but maybe some global design strategy could be used to save a few percent of the overall design process.

Thank you for your advice

RE: Mechanical engineer: how to work faster?

1. I like the idea of including most items in the model, but think if there are any ways they can be simplified so as to reduce modeling time. E.g on a chain do you model a link then build up an assembly of them? Or just model a 'loop' of the appropriate finished chain dimensions or...

Do you have a good library of parts? Do you use a lot of similar parts so could set up a more fleshed out template that automatically adds certain views or similar?

Do you have any standard calculations set up in matlab or excell or... so you can just plug the appropriate numbers in?

How much time do you spend on other stuff? For instance I have a few standard meetings that suck up my time more than you'd think. I also get involved in supporting quotes that takes up my time too.

How much of your time is spent on non work productive stuff like checking Eng-Tips (speaking of which gotta go...smile)

Posting guidelines FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm? (probably not aimed specifically at you)
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: Mechanical engineer: how to work faster?

(OP)
Hello Kenat, thank you for your input. You have raised a very good questions - they are certainly very important. Unfortunately everything is already optimized there...

Chains: yes, I model it fully. I need it for the exact length, I usually need a precise length of the chain. Besides, newer version of SW has the "Chain component pattern", which makes the design of the full length chain pretty simple. Besides, I often need special attachments on the chain, so I can't simplify anything here.

Library/templates: yes, it is set up. Standard parts are in the library (bolts, washers, bearings, and everything else). I don't want to go too deep here, but trust me - I have spent a fortune of time optimizing it and now it works fine and fast, and I can't make it any faster.

Calculations - yes, I use SMath - small program, which makes calculations more handy and easier (consequently - faster) than excel. When I have a new project - I use a file from previous project, adapt it, change numbers and make it work. Don't think can make anything faster here.

I use zero (none, absolutely) of my time on web browsing. I never have an unproductive meetings because I work alone - I design machines that my boss tells me to.
I sometimes discuss things with welders/machinery men about how to make the things better, and they often have good suggestions. So these discussions often lead to actually saving time on the long run.

I use Epiforge Grindstone to track my time. I clearly see that I don't have any unrelated activities, but the time it takes to design things make me suspicious that it should be possible to make some things faster... If only I knew how :)

RE: Mechanical engineer: how to work faster?

You may be down to the finite amount of time that it takes.
I am sure that some guys cut corners and get away with it, but not my style either.

"Of course I don't look busy, I did it right the first time"

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Mechanical engineer: how to work faster?

(OP)
Don't say that, I hope there is a hope to come up with something ..

RE: Mechanical engineer: how to work faster?

You only need to fully model chains if you're bad at math.

RE: Mechanical engineer: how to work faster?

"I use zero (none, absolutely) of my time on web browsing."

Well, I guess we now know that to be not entirely true (a little sharp edged humor, EighthBen, not malicious!)

Depending on the complexity of the machine, several weeks does not sound at all unreasonable. It's far better to be thorough and take an extra hour or two to prevent a mistake that may take days to fix, as you have said.

How have you come to the conclusion that you are taking too long? Is it by feedback from boss/supervisor, offhand comments by someone else, knowledge that someone else in a similar position performs more favorably?

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Mechanical engineer: how to work faster?

Time and experience.

It takes X number of keystrokes to draw a line and there's no 2 ways about it. It sounds like the only way to reduce time on a project/part is to review your design process. I'm not in the business of designing parts of cars with solid works, but something that helps me in designing HVAC and piping systems is to put pencil to paper before I even turn the computer on. (I can draw a line on paper a lot faster than I can in AutoCAD.) Once that's done, I'm less likely to move a line or block 20 times in CAD. The most useful tools I use are the triangles from my college days, a pencil and sketch paper with a scale and calculator not far behind.

Also, start putting together a library of what you've done in the past. I'm sure there are plenty of blocks and details (or whatever SW calls them) you can use from one job to the next, re-use them. (I'm sure you're already doing this to an extent, but find more.)

Take notes when talking to the welders, machinists, assembly guys and keep those notes at your desk. Ask them how you can make plans more understandable and do it. Drawing it once so they understand the first time is better than drawing it twice and having to explain your design in person.

At the end of the day, what works best for me is not what will work best for you, you will need to find a process that works best for you.

RE: Mechanical engineer: how to work faster?

(OP)
TheTick: I would appreciate if we wouldn't discuss the chain design further, otherwise it would require a completely separate discussion.

ornerynorsk: I mean I must use maedler.com, chiaravalli and other catalogs, find out how some things are calculated, and other things on the net. But I never read news or otherwise spend time during working hours.

dbill74: Yes, I sometimes do that, as much as paper allows it. But maybe I should to it more, because I edit thing quite a lot before I come to final design.

Library - yes, I do it, there are certain automation tools to reuse things in Solidworks and I make the best of it.

Notes: yes, I write a journal with the notes I get from welders and other workers and also a separate journal on how to make a design in the best way in Solidworks. I use them to remember the best practices that worked out.

As you see I tried quite a few things but I am still not satisfied with my speed. I believe the biggest brake is my lack of experience. So I came here to discuss if this could be partly overcome faster than naturally working in the field for years.

RE: Mechanical engineer: how to work faster?

3
One of the hardest parts of design for new designers to get a grip on is appropriate level of detail. There's a time for broad strokes and a time for needle-fine detail.

You seem to know a lot of the fine points of design and your design tools (e.g. SolidWorks). That's a good start, but it seems like you lack a framework for defining and starting a project and moving it through its stages of development. (At least you didn't think enough of it to mention.)

Perfection is rarely worth its price. There is such a thing as good enough. Does a miscount on hardware stop the whole show while someone flies 200 miles to buy it? Or do they get more from the bin? Are you holding up long-lead things like steel purchasing while you count your nuts?

RE: Mechanical engineer: how to work faster?

Tick implies a good question is your question:

1) Your 'touch time' while you're actually working on the project i.e. man hours not calendar weeks.

or

2) Total length of time of the project?

You imply 1 but thought I'd check.

Re. not modelling in all hardware, yes for one off or low volume work or similar may not be worth the effort for the sake of BOM accuracy etc. but...

Can be useful in things like making sure you have adequate clearances (Been bitten here when I didn't realize some rivet heads weren't modeled in) or even mass calculations etc. As well as clearly showing where it goes on drawings or work instructions or...

Posting guidelines FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm? (probably not aimed specifically at you)
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: Mechanical engineer: how to work faster?

There are two means of going faster - either making the parts of the task go faster or replace them/eliminate them entirely with different parts.

Were I hired as a consultant** for your problem, the first thing I would work on making a complete survey of what the final output is required to be like, what the type of input ordinarily given is, and what steps are required going from one to the other. Then we could look at what you think can go faster/ is currently unsatisfactory. When that flow is understood it's possible to see useless tasks and eliminate them and to look at characterizing the amount of time spent on the major tasks with an eye to both entire steps plus any common functions that are repeated across steps.

No different than any software performance analysis.

For example: I originally took 3 weeks to do a swept-volume analysis with a wire-frame/surface modeler. Then decreased that to 1 week with a bit of software I wrote. The third go around was going to be a day or less, but it required understanding the process to move from one speed to the next.

**I don't consult for anyone, so I'm not advertising.

RE: Mechanical engineer: how to work faster?

What do you actually producing from your models, paper drawings? cadcam etc etc.

Often there are numerous simple parts that similar across several products and these are often drawn individually, when a simple table drawing would define all possible configurations. How hard is it to find previously design parts that will do the job. I once worked where they designed subsea jumpers that used large numbers of straight and single bend tubing, they redrew the lot for each project because they used such a poor naming / part numbering convention that you couldn't find them. A couple of table drawings could have replaced the lot.

The first 5% of a programs efforts locks in about 80% of a program costs (number may vary but you get the drift), more focus on the design concept at the start might reduce the project time length.

RE: Mechanical engineer: how to work faster?

"Even a fairly simple machines takes 1-2 weeks or more to design, and when I look at the finished model - and I can't believe it took that much time."

Why do you feel spending 40-80 engineering hours to do a professional job designing and modelling a piece of machinery is excessive? Is your employer telling you that you need to work faster? Or are the machines you design incredibly simple devices, or slight modifications of existing products?

Consider that since we now rely heavily on the fidelity/accuracy of digital CAD models for functions like analysis, QA, manufacturing, etc, it is very important to make sure the CAD model is 100% accurate when released. Better to do the job right than to do it fast.

RE: Mechanical engineer: how to work faster?

There is a command in SolidWorks that I use as much as possible to speed up the design process.
It's the Pack-and-go command. Do you use it often?
When designing machines in SW most part types used will be common and thus used in previous projects too.
There are sheet metal parts (flat, angled, U shape, Omega shape, Z shape and such), rigid parts like round bars, profiles (not the design library parts!), hollow tubes, square tubes and so on. Parts based on extrudes and parts based on revolves etcetera.
So it is a handy trick to use packandgo with replacing the part/drawing numbers and thus quickly generate a new part-drawing combination. Then modify the part dimensions and use it in the new machine assembly.
Benefit is that in the background the attached part drawing is automatically updated. Once the parts are done (many features added like holes or deleted) and you like the assembly design you only have to clean-up the already attached part drawings.

RE: Mechanical engineer: how to work faster?

Unless you are being externally pressured to work faster I suspect that you are needlessly beating yourself up. What proportion of the total project cost and overall build time is being consumed by your work - I suspect it will be a fairly low percentage. Good design is an iterative process and it will take time. A few hours optimizing you designs so they are quicker, cheaper and easier to build is time well spent - if you are mainly assembling standard parts it sounds as if you have everything covered.
Finally, and without wanting to appear negative, if you work quicker what will you do with the time you have saved?

RE: Mechanical engineer: how to work faster?

Apart from my previous post about speeding up the SW design process there is another subject.
You call yourself a machanical engineer but you are not!
You are an assistant planner, an assistant purchaser and an assistant outsourcer and also an engineer.
This may sound silly but I read you use PDM.
Synonyms for PDM more often than not are: time-consuming, frustrating, bookkeeping, redundant, managers toy, innovation kill and so on.
In other words: look to the finished model with the eyes of a purchaser, a planner and an outsourcer as well.
Their time gain should be added to your engineering time frame!!

RE: Mechanical engineer: how to work faster?

EighthBen,

When you design machinery, or anything else for that matter, there is a certain amount of overhead work required to keep you organized. People pressuring you to speed up will tell you to not bother with this, and they will speed you up, in the short term.

I have repeatedly seen people complete mechanical design, and hand manufacturing a stack of fabrication drawings. They may have saved quite a bit of time by not bothering with assembly drawings and BOMs, but...

  1. ...manufacturing generated BOMs. Overall company effort was not saved.
  2. ...manufacturing took control of the drawings and BOMs. There was no point trying to reason with engineering, so they didn't. I hope any engineers reading this are cringing.
  3. ...the designs were atrocious. There was no attempt to view the completed system and do DFMA, or to visualize the structure, or to visualize how the system would be managed by the end user. The top level drawings are needed by manufacturing, and they are needed for design reviews and communication with other members of the design team.
This kind of bungling is harder to do with 3D CAD like SolidWorks. Then again, the parametric modelling provides all sorts of opportunities for screwing things up.
unless you absolutely have to. How much detail do you need on your chain? Each and every link probably is excessive.

Can you copy and paste from you BOM into your requisition forms? All that effort up from can save a lot of time downstream.

--
JHG

RE: Mechanical engineer: how to work faster?

One word I have not seen in this discussion is "modularity". By asking the initial question you are indicating that you are trying to be aware of and examine your own activities. In all my (many) jobs I have found ways to save time or energy by just looking for any time I am repeating some task. You already said you use previously designed components and sub-assemblies. That's good, but, are you looking ahead? All the time? Are you designing everything with the intent that some future version of your work will be used more than once? What dimensions are likely to change in the future? What other dimensions are affected by those changes? Can you design it so that by just changing one dimension you also change all the others that are affected by it? Do you design it with possible future configurations in mind? Do you organize these pre-planned components and sub-assemblies in some easily searchable database?

For example, one thing I commonly do in SW is to start with basic geometry sketches in which I will try to establish as many of the dimensional parameters as possible for the complete part within one or two sketches, maybe on the top and front planes. I leave those sketches alone and do not absorb them into Extrudes or Revolves. That makes them easier to access later. Then for the Extrude or Revolve sketches I use the Convert tool or relations to link as many parameters as possible to those basic geometry sketches. My philosophy is simple - minimal required changes to achieve the results. If I change something I want everything else affected by that change to change along with it.

I also commonly rename features according to their function, for example instead of "ExtrudeCut14" it will say "Machining_for_Gearbox_Base".

Just some thoughts...

RE: Mechanical engineer: how to work faster?

The edit function does not seem to be working. Somehow, I deleted a chunk of my reply.

Don't add unnecessary detail. For example, helices are hard on your video card. Don't model these unless you absolutely have to. How much detail do you need on your chain? Each and every link probably is excessive.

--
JHG

RE: Mechanical engineer: how to work faster?

What if any formal processes do you have in place?

For low volume work, the typical implementation of things like DFx, FMEA and all the other PLC alphabet soup tends to add quite a bit of overhead burden while having limited pay back.

I am not saying you shouldn't have any process, I'm saying they need to be the right processes implemented at the right scale and probably be quite flexible.

Posting guidelines FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm? (probably not aimed specifically at you)
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: Mechanical engineer: how to work faster?

3
EighthBen-

Welcome to the "Do it Right the First Time" Club. I assert that it ALWAYS takes someone longer IN THE SHORT RUN to do things if they: a) do it so that it won't need to be redone later and
b) spend the setup time it takes to make the next design go well and go quickly.

Of course it takes longer to do something in the short run. But in the LONG RUN you will win out with optimum processes, all the right information at your fingertips, and an efficient, methodical, thorough and sufficiently-documented approach.

I like to work this way but inevitably the "results by next quarter" management fixation does not reward long-run efficiency and a strong professional infrastructure (built over time) that produces robust, well-documented designs meeting all requirements and cost goals.

It is a damn shame how managers know to the minute how long it took to turn out a first design revision but do not have the maturity or desire to quantify how long it takes to fix a problem (e.g. missing dimensions, outdated industry standards, over-simplified drawing views, missing but necessary details) and revise the design until it is buried deeply in the production process (or with the customer) where it is so painful, expensive, embarrassing and time-consuming to fix. In their minds all this downstream work is just the cost of doing business. There are always people who do things "quick and dirty" who are richly rewarded. Rarely is a guy rewarded for preparedness and doing the job right the first time even if he can turn out better designs faster in the long run. I've been caught in the aftermath of so many "quick and dirty" types and it's no fun sweeping up behind them.

If anyone out there knows of a business that has such maturity and foresightedness please get my contact information from my profile and tell me who it is (confidentially of course). I want to work there!


Tunalover

RE: Mechanical engineer: how to work faster?

At a past employer, we had a saying, "There is never enough time to do it right the first time, but always enough overtime to fix it".

-Dave

NX 9, Teamcenter 10

RE: Mechanical engineer: how to work faster?

Tunalover, with the whole 'fail fast' philosophy being grossly miss applied all over the place - good luck finding that Nirvana.

However, you make a good point kudos to the OP for appearing to be diligent and conscientious about doing a good job first time.

Posting guidelines FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm? (probably not aimed specifically at you)
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: Mechanical engineer: how to work faster?

Take the time to talk to your "customers", the people using the results of your work. Are you giving them what they really need? Are you spending too much time on things they don't need?

One of the dangers of engineering design is that everyone wants to push off their documentation to your drawings. They want "one document to rule them all".pharaoh Are you adding information that is supposed to be documented elsewhere? Are you telling people how to do their jobs? These kinds of things must be purged.

RE: Mechanical engineer: how to work faster?

I have seen both ends of the spectrum at companies I have worked at when it comes to the engineering budget allotted by management for a given project. There were projects where management's bid included nothing for engineering costs, just so they could get the contract. So there was pressure to minimize the hours spent on engineering work. I have also worked on projects where the engineering was covered on a cost-plus basis. So there was no incentive to get the job done quickly.

RE: Mechanical engineer: how to work faster?

(OP)
Thank you everybody for your time and the input to this discussion. I apologize for my late reply, I was very busy last days. I shall now try to answer post-by-post.
PS - I definitely see the need to improve the interface of this forum for better quoting possibility ...

RE: Mechanical engineer: how to work faster?

(OP)

Quote (TheTick)


TheTick (Mechanical)
1 Aug 16 22:28
One of the hardest parts of design for new designers to get a grip on is appropriate level of detail. There's a time for broad strokes and a time for needle-fine detail.

You seem to know a lot of the fine points of design and your design tools (e.g. SolidWorks). That's a good start, but it seems like you lack a framework for defining and starting a project and moving it through its stages of development. (At least you didn't think enough of it to mention.)
This is true. I have noticed myself that I quite often tend to use too much detail at the beginning of the design process, and if changes appear - certain amount of this work is lost. I shall try to improve this behavior of mine. Thank you for the advice.

RE: Mechanical engineer: how to work faster?

(OP)

Quote (3DDave )



3DDave (Aerospace)
2 Aug 16 00:31
There are two means of going faster - either making the parts of the task go faster or replace them/eliminate them entirely with different parts.

Were I hired as a consultant** for your problem, the first thing I would work on making a complete survey of what the final output is required to be like, what the type of input ordinarily given is, and what steps are required going from one to the other. Then we could look at what you think can go faster/ is currently unsatisfactory. When that flow is understood it's possible to see useless tasks and eliminate them and to look at characterizing the amount of time spent on the major tasks with an eye to both entire steps plus any common functions that are repeated across steps.
Yes, learning to ask appropriate questions at the beginning of the design process in order to understand the task better is a must. I am doing my best on it. Also, as I said, first should be the basic design, and details should be the last. I sometimes mix this order.

RE: Mechanical engineer: how to work faster?

(OP)

Quote (tbuelna )



tbuelna (Aerospace)
2 Aug 16 02:57
"Even a fairly simple machines takes 1-2 weeks or more to design, and when I look at the finished model - and I can't believe it took that much time."

Why do you feel spending 40-80 engineering hours to do a professional job designing and modelling a piece of machinery is excessive? Is your employer telling you that you need to work faster? Or are the machines you design incredibly simple devices, or slight modifications of existing products?

Consider that since we now rely heavily on the fidelity/accuracy of digital CAD models for functions like analysis, QA, manufacturing, etc, it is very important to make sure the CAD model is 100% accurate when released. Better to do the job right than to do it fast.
Exact hours spent on the project design depends on the complexity of it. I often get a feedback from my boss that it takes too long for me, and I often agree (although not always, because sometimes he changes the design intent after I am almost finished with every single nut). Surely, better to do the job the first time, but it is even better to make it faster AND right. Now we are here discussing how to do that :)

RE: Mechanical engineer: how to work faster?

(OP)

Quote (jlnsol )



jlnsol (Mechanical)
2 Aug 16 07:35
There is a command in SolidWorks that I use as much as possible to speed up the design process.
It's the Pack-and-go command. Do you use it often?

Yes, I take the advantage of it when appropriate. Furthermore, there are functions in PDM like "Move tree" and "Copy tree" - sometimes even better than PAG.

RE: Mechanical engineer: how to work faster?

(OP)

Quote (DerbyLoco)


(Mechanical)
2 Aug 16 09:37
Unless you are being externally pressured to work faster I suspect that you are needlessly beating yourself up. What proportion of the total project cost and overall build time is being consumed by your work - I suspect it will be a fairly low percentage. Good design is an iterative process and it will take time. A few hours optimizing you designs so they are quicker, cheaper and easier to build is time well spent - if you are mainly assembling standard parts it sounds as if you have everything covered.
Finally, and without wanting to appear negative, if you work quicker what will you do with the time you have saved?
My engineering usually takes about 25-50 percent of an overall project time. We have about 15 people in manufacturing, so they build the product fairly quick. Again, we (me?) are here just to find some ideas how to improve the efficiency of constructing and engineering ...

RE: Mechanical engineer: how to work faster?

(OP)

Quote (jlnsol )


jlnsol (Mechanical)
2 Aug 16 11:21

You call yourself a machanical engineer but you are not!
You are an assistant planner, an assistant purchaser and an assistant outsourcer and also an engineer.
This may sound silly but I read you use PDM.
Synonyms for PDM more often than not are: time-consuming, frustrating, bookkeeping, redundant, managers toy, innovation kill and so on.


I don't know what are you talking about. PDM is a file management system with lots of useful functions. It definitely is NOT time-consuming, frustrating or anything else negative. Furthermore, it is actually inevitable.

RE: Mechanical engineer: how to work faster?

From your responses, it sounds like implementing design 101 more robustly, i.e. "Know Thy Requirement", may help.

Additionally sounds like a design review step after you have your general concept but before you get too far into details may be a good idea.

Thinking about details early on isn't a bad thing as it can avoid costly re-designs later to address 'details' but, ideally you shouldn't invest too much time in details that might change as the design process progresses.


BTW, all those quotes could have been in one post - not sure why separate posts.

Posting guidelines FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm? (probably not aimed specifically at you)
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: Mechanical engineer: how to work faster?

(OP)

Quote (Jboggs )


Jboggs (Mechanical)
2 Aug 16 17:58
One word I have not seen in this discussion is "modularity". By asking the initial question you are indicating that you are trying to be aware of and examine your own activities. In all my (many) jobs I have found ways to save time or energy by just looking for any time I am repeating some task. You already said you use previously designed components and sub-assemblies. That's good, but, are you looking ahead? All the time? Are you designing everything with the intent that some future version of your work will be used more than once? What dimensions are likely to change in the future? What other dimensions are affected by those changes? Can you design it so that by just changing one dimension you also change all the others that are affected by it? Do you design it with possible future configurations in mind? Do you organize these pre-planned components and sub-assemblies in some easily searchable database?
Yes, I take into account the possible future designs, and I use my modeling technique a good as I can for that. But to be fair - all my designs are pretty unique, so this actually doesn't save me anything. I do it, because you never know when something is going to change, but it wouldn't save my time.

RE: Mechanical engineer: how to work faster?

(OP)

Quote (tunalover )


tunalover (Mechanical)
3 Aug 16 02:43
EighthBen-

Welcome to the "Do it Right the First Time" Club. I assert that it ALWAYS takes someone longer IN THE SHORT RUN to do things if they: a) do it so that it won't need to be redone later and
b) spend the setup time it takes to make the next design go well and go quickly.
a) yes, appropriate amount of time spent on the project is actually a time save. I do my best to perform it, and I actually do fairly little amount of mistakes
b) I should think more about the setup and design strategy before starting the design project. I agree, I will think how can I do it. Thank you for the advice.

RE: Mechanical engineer: how to work faster?

(OP)

Quote (TheTick )


TheTick (Mechanical)
3 Aug 16 14:49
Take the time to talk to your "customers", the people using the results of your work. Are you giving them what they really need? Are you spending too much time on things they don't need?
My customer is my boss. We design machines and then use it in our own sawmill, we do not sell it to third party.

RE: Mechanical engineer: how to work faster?

(OP)

Quote (KENAT)



From your responses, it sounds like implementing design 101 more robustly, i.e. "Know Thy Requirement", may help.

Additionally sounds like a design review step after you have your general concept but before you get too far into details may be a good idea.

Thinking about details early on isn't a bad thing as it can avoid costly re-designs later to address 'details', but ideally you shouldn't invest too much time in details that might change as the design process progresses.


After spending much effort on analyzing my work and it's efficiency for the last week, this is exactly what my conclusion is. Those three steps may be the (only?) key to improve the efficiency of my work. This discussion have surely helped me to crystallize this. Thank you again for participating in it.

RE: Mechanical engineer: how to work faster?

Early on in my career I tried to work fast at the expense of accuracy and i missed some details. Lucky I had a older fantastic boss that sat me down and told me when i give you a task I am not impressed if you do it faster than I thought it would take. I do care if it has errors, rule number one is it has to be right. I have had that same discussion with almost every new grad I have worked with. I don't have much to add to the thread besides what has already been stated but kudos to the OP for wanting to increase his speed but don't be too hard on yourself.

RE: Mechanical engineer: how to work faster?

I had a similar experience. This is not at all an excuse for missing a project deadline, but it is still a true statement: "Five years from now no one will know if the project was a week late, but they will by God know if it works!"

RE: Mechanical engineer: how to work faster?

A graph of percent of design completion vs time would show an exponential curve with the amount of time to fully finish a design approaching an asymptote of infinity (obviously not quite there, but conceptually close). Completing the first 90 percent of the design takes 50 percent of the overall schedule. Completing the final 9 percent of the design takes the last 50 percent of the schedule. The trick to saving overall schedule is to know what level of completion is good enough. Do you really need to be 99 percent complete to start manufacturing or is 95 percent good enough? Note that you can virtually never have a fully optimized or complete design. This is evidenced by the fact that products that have been manufactured for years still have periodic refinements. There's always something you could have done better or more completely.

What do you and your boss think a good amount of time to design one of these machines would be? With your current design process what level of complete are you at that time? Is the machine able to be manufactured at that level of complete considering an acceptable amount of questions from the shop?

Another thought, are there other examples in the industry of similar items being designed in the time frame that you and your boss are hoping for? If yes, then either they begin manufacturing at a different level of completion than you, or they have a better design process then you. If there aren't any other examples, then maybe you and your boss have un-realistic expectations for yourself.

RE: Mechanical engineer: how to work faster?

Books of general interest:

The Mythical Man Month (Brooks)
Death March (Yourdon)

RE: Mechanical engineer: how to work faster?

For me the concept design stage is usually a bunch of pencil sketches on scrap paper. Allows plenty of iterations without wasting time putting detail into 3D models.

je suis charlie

RE: Mechanical engineer: how to work faster?

gruntguru,

It depends on what you are designing. A mechanism or action can easily be shown as a pencil sketch. Most of my messy design problems come from having to stuff something into limited space. I start designing with whatever scale tool I have, be it drafting board, 2D&nhsp;CAD or 3D CAD. A preliminary 3D model can be whipped up very quickly, and then inspected and reviewed. Usually, it is worthwhile to model several design concepts, especially if fabrication is going to cost a lot more than engineering.

If you want to do DFMA or any other fancy engineering technique, you need to start off and investigate several design concepts.

--
JHG

RE: Mechanical engineer: how to work faster?

In my experience one of the most common wastes of time is simply unnecessary model iteration. I too usually start with a series of pencil sketches and hand calcs to identify areas of interest or concern, then I set up the necessary spreadsheets and simulations, and finally use the results to drive my solid model. Yes, engineering is an iterative process of design, test, repeat...but if you need to iterate your solid model 5x before test simply to make everything fit and work then you missed a step. At the risk of sounding negative, to me thats the difference between a true engineer and the proverbial "CAD jockey."

RE: Mechanical engineer: how to work faster?

"In my experience one of the most common wastes of time is simply unnecessary model iteration. I too usually start with a series of pencil sketches and hand calcs to identify areas of interest or concern, then I set up the necessary spreadsheets and simulations, and finally use the results to drive my solid model. Yes, engineering is an iterative process of design, test, repeat...but if you need to iterate your solid model 5x before test simply to make everything fit and work then you missed a step."

I agree with your approach of using sketches/layouts/spreadsheets/simulations to optimize a new design prior to expending engineering resources constructing a high fidelity digital CAD database. Modern digital CAD databases use a complex system of relationships and links between files, and if the parent models are not constructed with care it can cause lots of problems and rework later on.

However, in my experience a process of "design, test, repeat..." is not normal practice. Testing costs money and takes time. Instead the design is validated by analysis, and then if required the analysis work is validated by qual testing. It's more like, "design, analyze, repeat until the analysis confirms the design meets requirements.....then if required conduct qualification testing to validate analysis work."

RE: Mechanical engineer: how to work faster?

justalearnin,

A lot of model iteration is communication with co-workers.

"That's not what I meant."

"Ooh, that's cool, but how about this?"

"Oh, is that really what it winds up looking like?"

"Wow, you can do that? That lets me do this..."

Many years ago, a manager asked me something, and I quickly free-hand sketched up a mechanism. It worked, and the manager announced that we should do all design like that. I was horrified. Usually, I am stuffing lenses, mirrors and beamsplitters into a tiny space. The available space usually is my primary design problem, followed by figuring out how people are going to get at stuff.

I am designing furniture here at home. Sometimes, I start with a free-hand sketch. Sometimes I go straight to LibreCAD. It all depends on what I do not understand yet.

--
JHG

RE: Mechanical engineer: how to work faster?

Drawoh,

Sketches? CAD? Pah.

I needed to make a camera filter adapter, and walked out to my garage, and found a piece of acetal that looked about right. Started whittling on it with my lathe, messed up the threads twice, ended up with a too-short piece of acetal (thus verifying the cut-twice measure once principle), redid the whole thing in PVC, realized that I'd not be able to turn the i.d. without clamping on my just-completed threads (home mini lathe jaws too short) and had to come to use the big lathe at work. Turned the i.d. at work based on memory of what the diameter needed to be to slip over my scope, came home and checked, found was off by about .01", back to work, home again, there we go.

Design by messing around, I think it's known as "puttering".

RE: Mechanical engineer: how to work faster?

However, in my experience a process of "design, test, repeat..." is not normal practice. Testing costs money and takes time. Instead the design is validated by analysis, and then if required the analysis work is validated by qual testing. It's more like, "design, analyze, repeat until the analysis confirms the design meets requirements.....then if required conduct qualification testing to validate analysis work."

I believe for the first part we are disagreeing mainly on semantics as analysis is usually considered a significant part of the overall design process.

A lot of model iteration is communication with co-workers.

I would suggest that one of the biggest challenges in life is communication. Realistically though, if you are losing more than an hour or two a week (~2-5% of your time) early in the design phase then I would recommend you do what is necessary to address that issue. Both lean and agile philosophies have some useful tools from daily standup meetings to task boards not to mention all manner of project management software to assist with this. Nobody lives in a perfect world, but miscommunication shouldn't drive "a lot" of work on anybody's part.

RE: Mechanical engineer: how to work faster?

justalearnin,

I am not arguing that my co-workers are uncommunicative goofs. I am arguing that as the mechanical designer, I do not know everything. The requirements of electronics, optics (in my case), manufacturing and the end user must be taken into account. This means communication.

My book on DFMA (Boothroyed, Dewhurst, Knight) has a graphic that shows that engineering affects about 70% of the cost of the product. In reality, this value should vary wildly. In the case of the OP, it might be on the low side, given that it is one-off plant equipment.

How about we estimate the total cost of manufacturing all of the product, and budget some percentage of that for engineering? If the total manufacturing cost is high, the designers should take the extra time, do extra analysis, and try several alternate designs, and look for ways to be clever. If the manufacturing is relatively cheap, then engineering must work fast. It would be a good idea to select relatively expensive, reliable components to eliminate as much debugging as possible.

--
JHG

RE: Mechanical engineer: how to work faster?

Like drawowh, I spend a lot of my time playing geometry games trying to fit everything into the available space, then allow for realistic manufacturing tolerances (not that many of my colleagues both with that part), usability, manufacturing ... so I do tend to jump to CAD pretty quickly when I know what I'm going to do. However, I also have plenty of sketches around too from when I get to to a bit more brainstormning.

The guys I admire, and really should try and emulate more, are the ones that manage to refine the basic problem to some mathematical relationship(s) and crunch through that. Now like I said a lot of my problems are softer geometry related issues but still should do better.

Something to look out for is applying the wrong/inappropriate model of project management or design process or whatever as I alluded to early.

Some philosophies that may make sense for say software when the '0' & '1' can be re juggled relatively quickly with almost immediate results may not make sense for hardware projects where you need to design, document, produce tooling for the part then make the part....

Philosophies like fail fast, fail option may perhaps make sense used correctly. However, when failing for entirely predictable reasons like tolerance stacks or similar the I'm sorry but it's no longer engineering by any measure - more the puttering Btrue mentioned.

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