How often does something not work'

[pipeclay]

Just curious as to what percentage of jobs/projects people do/ attempt with out having a problem.
I think at present I am achieving an 80% strike rate with jobs/projects working the 1st time without having to either rework a job or start again.
A lot of times I do things in the correct order of opperation/planning but other times I weigh up the risk Pass/Fail.

[new_guy90]

elaborate more?

[pipeclay]

Not sure what more to say or ask,how often does it work the 1st time you make it.

[Stustoys]

Hi PC,
Do you mean "how often to I paint myself into a corner and have to start over"?
Not very often, though I do find myself having to change the order of things along the way and a simple job turns into a major pita. Hard to put a number on it but I wouldn't think it was as high as 20%, but I tend to do far more thinking than doing lol, I think if I did more, bin more and think a little less at the end of the day I'd get more done.

Stuart

p.s., thinking about it a more, most of my jobs are pretty simple so much less room for problems. If I had a job with 45 operations I'd likely paint myself into 5 corners.

[azzrock]

well id have to say 80% from scratch is excellent.
if i could plan correctly from start to finish 50 % of the time with out having to back track or change something id be happy . i am fairly implosive.
well done pipeclay

[pipeclay]

I mean how often does a job/project your working on go from start to finish as planned.
This could be with or without proper drawings or designs you have in your head.
I suppose it more so stems from a job Im doing for a member here at the moment,I have a drawing/cad diagram,sizes given (ball park),had to machine a mandrel,that was good,had to make a collar.want .0015" interference,ended up being size for size.
Held mandrel in collet chuck,put collar on mandrel attached to collet chuck,thought collet chuck would grab mandrel well enough not to pull out,when job was tightened on mandrel,worked ok till a little vibration the it started to loosen.
finish machine job to size ready for gear cutting,first cut on OD good second cut a step(not good) removed job renmachined od of part,fitted new part again,drilled and tapped collar and dimpled shaft,now ok,should of either machined a new collar or dimpled shaft first time rather than thinking it would be ok.

[simonl]

Hardly ever does a job go from start to finish without an "adjustment" often than not this involves a slight change in the plans after either a mistake or more likely I tweak the design as an improvement to my original design. I can tolerate the occasional mistake if I'm attempting something new and I learn from the mistake. What I can't tolerate are mistakes from me being careless or from being in too much of a hurry. Mistakes that cost a considerable amount of money hurt too, luckily they don't happen that often.

My dad once said a person who has not made a mistake probably hasn't made anything...

CHeers,

Simon:U

[PDW]

I mean how often does a job/project your working on go from start to finish as planned.


My sailboat build is going exactly as planned.

It's running over time & over budget.

PDW

[19brendan81]

My main issue is underestimating how long jobs take....Im talking all sorts of house type projects here, building a pergola, installing insulation, building a pizza oven etc. I do this all the time, generally by half. (I.E I think something will take 5 hours and it actually takes 10).

With metalworking, I regularly change plans halfway through when I realise theres a better approach than what I had planned/attempted. Im still learning, so pretty much everything I do is attempted twice, or if not...I realise at the end that there was a way better option than the method I took. The hydraulic pipe bender I built from scratch was pretty well built twice.

[BobL]

My main issue is underestimating how long jobs take....

Yep - that's me too. Because I do more WW than MW and so think I am a bit more competent at WW I generally underestimate the time for WW jobs and sometimes over estimate time for MW jobs.

One thing I thought would help in maintaining time to completion is skill in recovering from stuff ups, but no matter how many tips and tricks I learn I do not seem to be getting any faster - not that I am after speed, what I'm after is enjoyment. Some of this is because one keeps tackling more complex tasks so at least some part of the task is a new experience.

I find I enjoy the work much more and reach the end of the task when there is no deadline. As soon as a deadline is involved the FUF inevitably pays me (several) visits and slows me right down, I waste material and frustration sets in.

With innovative/creative stuff I find it useful to sometimes make a complete prototype or prototypes of one or more of the components to see how they will work. If I don't factor this into any timeline then my time to completion blows right out. These days I start by designing prototypes and take it from there.

Actually now that I think of it a thread that deals with "recovering from a MW stuff up" could be a really handy one. Some of us are perhaps reluctant to admit we make mistakes but we all do and as my high school MW teacher says, a big difference between an amateur and a professional is how well they recover from, and cover up, a stuff up.

[chambezio]

When I was working full time and only having short periods of time to work on a project actually worked well. By a weekends end I would nut out the next step but could not proceed because of no time. During that next week I would go over and over what I was going to do and a lot of the time would come up with a plan for the next part using less material and a better way to get a result.
But now.....only doing a little part time work so plenty of time to spend on projects..........complacency steps in along with "later" and TV and so projects take so long to get done. And yes some monumental cockups that I beat myself up severely about. The depression usually saps away any feeling of accomplishment and turns in into complacency (and that turns to frustration)
I do remember a little job that needed to be done for 2 years when I was working. There was a plumbing vent pipe that came through the verandah floor and continued straight up through the verandah roof to vent out above the roof line. As a quick and tempory measure i just leaned the pipe at 45 degrees to get the smell up and away. Then came time to finish off the other end of the house and this pipe was in the way and had to be put into its proper position (Directly plumb over where it came through the verandah floor). I remember I kept putting it off. I reckoned it was going to be awkward and fiddly and a real PITA and take a long time to drill a 55mm hole in the fibro ceiling then same hole through corrugated iron roof......I had it done in 15 minutes. It took longer to tidy up the tools to do the job.
My dear old dad used to talk about "5 minute jobs". You know the ones! The 5 minute jobs that take half a day

[Anorak Bob]

I had posted a reply yesterday but deleted it thinking that I would be an orphan in confessing the number of mistakes I've made. When I made my slotting head for the little Hercus mill, I realised I had made the ram guide upside down, started on version 2 only to find that the holes I used to fix the 8 inch round slice of cast bar to the lathe faceplate were where the dovetails would be machined. I had success on version 3. My Hercus rotary table, purchased as just the base casting, has the third table I made fitted. I used a lot of expensive cast iron in the process of making these things. A lack of resolved drawings is often the cause of machining errors along with the habit of machining undersize.

I have found that I make less mistakes, sometimes none, on more complicated projects. Could be that they require more consideration and concentration. I tend to spend a lot of time working out how I am going to hold something, especially on the mill.

You would think that as time went on one would become better versed in these skills and make less errors but with metalworking as a hobby there is so much to learn and trying new things involves risk. Risk often leading to small failures. A lot of us are self taught and this forum provides a valuable source of advice and guidance. I for one have learnt a lot from you blokes.

BT

[Abratool]

I had posted a reply yesterday but deleted it thinking that I would be an orphan in confessing the number of mistakes I've made. When I made my slotting head for the little Hercus mill, I realised I had made the ram guide upside down, started on version 2 only to find that the holes I used to fix the 8 inch round slice of cast bar to the lathe faceplate were where the dovetails would be machined. I had success on version 3. My Hercus rotary table, purchased as just the base casting, has the third table I made fitted. I used a lot of expensive cast iron in the process of making these things. A lack of resolved drawings is often the cause of machining errors along with the habit of machining undersize.

I have found that I make less mistakes, sometimes none, on more complicated projects. Could be that they require more consideration and concentration. I tend to spend a lot of time working out how I am going to hold something, especially on the mill.

You would think that as time went on one would become better versed in these skills and make less errors but with metalworking as a hobby there is so much to learn and trying new things involves risk. Risk often leading to small failures. A lot of us are self taught and this forum provides a valuable source of advice and guidance. I for one have learnt a lot from you blokes.

BT
Likewise, I have learnt heaps from all of you blokes.
My main problem now is that I spend a lot of time reading up on the Metalwork Forum.
There is just so much knowledge out there.:2tsup:
Thank you all.
regards
Bruce

[RayG]

I don't think I've ever made anything without making changes as I go, so on that score my strike rate is zero.. :)

On the other hand, most things usually work out even if it takes longer than I first thought.

The biggest trap I find is not anticipating work holding problems, mostly because I get the order of operations backwards, and find I have to make special clamping or jigs that I wouldn't have had to do if I things were done in a different order.

To my mind, that's just the nature of making one off stuff, (always the same with prototypes) if you have to make a production run of something, then you take what you learn and make improvements to the process as you go.

If it's a complete disaster, undersized, or just doesn't work, you can always melt it down and cast it into something else... :D

Regards
Ray

[BobL]

One area where I have learned the hard way is fitting supposedly symmetrical pieces together. I learned that even if they are symmetrical unless they are marked for orientation before drilling they simply won't go on just any which way!

[WelderMick]

Sometimes I'm pleasantly surprised.... I make a prototype - just to iron out the mistakes, but in the end this is often the only version that gets made. That's a rare thing though! Cheers - Mick

[Michael G]

It depends on what I'm doing-
These days I rarely have to grind out a stick weld and re do it. My success rate with TIG is not as good.
80% of the time I can turn a bore to within a thou, but sheet metal is a 50/50 affair as I still have trouble with bend allowances.
External threads I have no problems with, but internal ones still give me problems. I sometimes have to have a couple of goes to get a HSS lathe tool ground right, but drill bits I can do freehand without mucking them up most of the time.

I'm always learning.

Michael

[Bryan]

'How often does something not work'? A project of mine almost never goes flawlessly, but almost always works in the end. In between is where the creativity, learning and fun is. Sorry if that's too general, but I'm not sure I see the point of the question. Unless it's about commercial efficiency, in which case I'm not qualified to answer.

[azzrock]

I mean how often does a job/project your working on go from start to finish as planned.
This could be with or without proper drawings or designs you have in your head.
I suppose it more so stems from a job Im doing for a member here at the moment,I have a drawing/cad diagram,sizes given (ball park),had to machine a mandrel,that was good,had to make a collar.want .0015" interference,ended up being size for size.
Held mandrel in collet chuck,put collar on mandrel attached to collet chuck,thought collet chuck would grab mandrel well enough not to pull out,when job was tightened on mandrel,worked ok till a little vibration the it started to loosen.
finish machine job to size ready for gear cutting,first cut on OD good second cut a step(not good) removed job renmachined od of part,fitted new part again,drilled and tapped collar and dimpled shaft,now ok,should of either machined a new collar or dimpled shaft first time rather than thinking it would be ok.

hi pipe clay. so if im reading this right you had a gear blank that you wanted to mount on a mandrel so you could hold it in your indexing head to cut the gears?
is that it?
do you have any photos. why did you change the size of the collor from what you planed. Im shore some people don't find it hard but i do . to go from idea to finished part. Getting the machining order and every thing else right. I remember cutting a gear for an important job that people where waiting on it all went fantastic i was happy with myself and the job. only problem is the od was way undersize making it virtually useless
I still say 80% is great

[pipeclay]

I suppose my question was not as accurate as it should of been,but what it was intended to ask is how often you do a job,where you know what you should do but you take a risk on changeing the method slightly, due to the materials you have or the time involved to do it correctly.

I could of made another collar but when weighing the risks of it not working I thought the collet would of held enough not to allow the mandrel to pull out,unfortunately it didnt.

This was the offending collar that was not shrunk onto the mandrel,after it allowed the mandrel to be pulled through the collet chuck the collar was drilled and taped and the mandrel dimpled,no further movement was noticed.