# How long is a piece of string....



## mwilkes (Dec 5, 2012)

Just wondering....

I reckon my Stuart 10V took about 60-70 hours to build (so far...I could probably spend another 70 hours fixing my mistakes). In your opinion would that be "too fast", "too slow" or "about right"?

And on the same subject - how long do people reckon it takes to do a Stuart Twin/Compound launch engine? :hDe:


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## 110samec (Dec 5, 2012)

Don't know about them but I do know the length of a piece of a string...



...its twice the distance between the centre and the end


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## Marty Feldman (Dec 5, 2012)

I assume that your title is meant as a takeoff on the fractals business.  If so, congratulations.  

While your hours count seems in the reasonable realm, I have always mistrusted statements of how many hours one has in a project.  From my personal perspective, it is a meaningless number in the absence of details as to how it was computed and exactly what type and level of effort went into each hour.  These are details which are tedious, and difficult to get interested in.  One's technique, materials, and machines might cause many "building" hours to be spent sharpening tools.  One might spend a considerable amount of time studying plans, and then planning the order in which to do things.  There is time spent in ordering and gathering up what will be needed for the day's planned work.  Then there's oiling, and measuring, and fitting, and fixing errors.  You could argue that such things, and many more like them, should not be counted in the hours total, but how can you not count them?  Noone goes into the workshop and just turns on a machine and bang, the chips are flying in minute number 1.  Among other variables is the matter of experience.  Those of you who are old hands, with lots of experience under your belts, are liable to log more productivity in an hour than others who are nearer the beginning of the learning process.  The same sort of variation occurs with respect to what is a "finished" project.  For a master craftsman, the number of total hours in a project often sounds like a pretty big number, but one reason for that is the time it takes to get to the level of detail and perfection that has become his standard.  Those just starting out, on the other hand, are likely to declare victory at an earlier stage of completion of the project.

Sorry to be so long winded about this, but I did want to get across the notion that, to me at least, hours should be the last thing to attach any importance to.   The important things are doing the best you can on every job, learning how to do it better, and then doing a better job the next time.


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## mwilkes (Dec 5, 2012)

True and wise words eloquently put, Mr Feldman. Thanks


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## idahoan (Dec 5, 2012)

It's a hobby; I never keep track of time spent. Many of my projects are measured in years; not hours or days.

Dave


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## Tin Falcon (Dec 5, 2012)

Like others have said , it is a hobby you do not need to worry about the clock. 
there used to be a guy here that claimed he could machine a  10 H or a 1Ov in 8 hours. I expect he had a good number of hours invested in the tooling to do it. 
A couple of my early builds simple oscillators took a week start to finish I expect about 16 hours or so actual machining time. IIRC most or many of the pm research projects are estimated at 40-50 hours. 
it depends how organized and focused you are. My shop is off the kitchen  so always handy . unfortunate I am subject to frequent interruptions and distractions.  The last time I tried to make and engine in a week it took a month. 
do not worry about the clock have fun you completed an engine that is a success.



A sting is whatever length it was cut to .  
Tin


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## kf2qd (Dec 5, 2012)

Are you measuring with a yardstick or a clock???


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## KBC (Dec 6, 2012)

mwilkes said:


> Just wondering....
> 
> I reckon my Stuart 10V took about 60-70 hours to build (so far...I could probably spend another 70 hours fixing my mistakes). In your opinion would that be "too fast", "too slow" or "about right"?
> 
> And on the same subject - how long do people reckon it takes to do a Stuart Twin/Compound launch engine? :hDe:



Have a look at my posting (http://www.homemodelenginemachinist.com/f23/stuart-turner-launch-engine-con-rod-17379/  further down the page and it will give you some ideas on this engine which include some trials and tribulations on the build and some modifications to some of the parts.
One thing for sure it's not a 60-70 hr build, castings in general very poor and drawings not too clear, I can't recommend it and for sure I would never build another.
I can recommend the D10 but I would wait until the new company starts selling castings and see what sort of opinion is given by members who have tried them

George.


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## Charles Lamont (Dec 6, 2012)

KBC said:


> ... castings in general very poor ...
> 
> ... I would wait until the new company starts selling castings and see what sort of opinion is given by members who have tried them



I have spoken to them at an exhibition. They said the scrapped 70% of the iron castings they acquired with the company, and could not even use them when re-melted. From the web site they seem to be restocking the range pretty efficiently. Even the 6A and Sirius are available again. Their stand also had an example of the 30cc(?) Stuart 'Lightweight' 2-stroke, which they are keen to reintroduce as a change from steam.


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## mwilkes (Dec 6, 2012)

@Charles - that's interesting. I thought the company that bought Stuart (bridport foundry) had been making Stuart's castings all along. I had castings problems even with the 10V, but actually I quite enjoyed the struggle!

I noticed they are now producing castings for the crankshafts for the Compound & Twin as well as the 10V/10H. And the No.1 is back too. Nice to see that they're trying to reclaim Stuart's former glory; though you have to drill down in to their 'news' section to find out, and then you can't buy it online. Pity their web skills aren't as good as their casting skills!

@George - yep, I've read your post in great detail. Excellent post and extremely useful. If I ever start, and ever finish, a twin launch, I shall be standing on the shoulders of giants...


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## KBC (Dec 6, 2012)

mwilkes said:


> @Charles - that's interesting. I thought the company that bought Stuart (bridport foundry) had been making Stuart's castings all along. I had castings problems even with the 10V, but actually I quite enjoyed the struggle!
> 
> I noticed they are now producing castings for the crankshafts for the Compound & Twin as well as the 10V/10H. And the No.1 is back too. Nice to see that they're trying to reclaim Stuart's former glory; though you have to drill down in to their 'news' section to find out, and then you can't buy it online. Pity their web skills aren't as good as their casting skills!
> 
> @George - yep, I've read your post in great detail. Excellent post and extremely useful. If I ever start, and ever finish, a twin launch, I shall be standing on the shoulders of giants...



I was just about to thank Charles for the info on Stuart so thanks Charles, it may be a bit easier to get spares now with the new owners.

mwilkes or is it Mike.

I think that you will find that the crank shafts will be forgings rather than castings, unless they are going to cast them in steel.

Do you know that the Compound engine isn't self starting and on purchasing the set of castings there are very few actual castings but plenty of bar stock for shaping.
The Launch engine and the Compound make super models but you will need a very large boiler to feed them and I think that you would struggle a bit with your Petol set up.
If that's what you have and a desire to build the Compound just go for it, keep your tools sharp and at the correct height.

Regards 
George.


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## skyline1 (Dec 7, 2012)

I too had problems with poor Stuart castings in the past. I Started a D10 about 10 years ago and had to abandon (and return) it as many of the castings were unmachinable and some had no machining allowance at all in fact they were less than finished dimension. This meant that I would have had to deviate from the drawings to build it even if I could actually machine it. The boxbed was a typical example the first casting which came with the kit was so hard and chilled it actually cracked trying to machine it. I couldn't get through it with any tools H.S.S. or Carbide. Having successfully machined iron cast in my own foundry I decided that it wasn't my skills or machines at fault. It was returned to Stuarts and they sent a replacement. This was just as bad as the first one, possibly worse, I gave it to a friend who had access to a surface grinder, he managed to skim it flat for me but said it was tricky even surface grinding it.

It is good to hear that Stuart is being run by engineers again. During their time in Guernsey it was owned by a manufacturer of office furniture. It is also good to see the return of the old forged crankshafts on some of the Models. 

I don't mind paying a premium price if you get a premium product and I hope to see a return of the old Stuart quality.

Regards Mark


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## charlesfitton (Dec 7, 2012)

110samec said:


> Don't know about them but I do know the length of a piece of a string...
> 
> ...its twice the distance between the centre and the end


 

the other we were always asked 

"What is the weight of a pull through?"   (string for cleaning rifles)

f


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## mwilkes (Dec 7, 2012)

@George - I'm aware that I'm biting off a little more than I can chew, and I expect it to be character-building! If nothing else, it's a good excuse to invest in a decent milling machine...

I like the fact that it's mostly a bar-stock kit (with none of the bar-stock supplied, it seems!) - it makes it easier to accomplish, because there'll be fewer castings to mangle.

MarkW


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## johnnyo (Dec 7, 2012)

Length of string? I'm still trying to figure out what gold is made of.


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## Charles Lamont (Dec 7, 2012)

> Nice to see that they're trying to reclaim Stuart's former glory; though you have to drill down in to their 'news' section to find out, and then you can't buy it online. Pity their web skills aren't as good as their casting skills!


I told them they needed to update the web site. They said they knew that but were concentrating on production first, and bemoaned the cost of professional web site work.


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## KBC (Dec 7, 2012)

mwilkes said:


> @George - I'm aware that I'm biting off a little more than I can chew, and I expect it to be character-building! If nothing else, it's a good excuse to invest in a decent milling machine...
> 
> I like the fact that it's mostly a bar-stock kit (with none of the bar-stock supplied, it seems!) - it makes it easier to accomplish, because there'll be fewer castings to mangle.
> 
> MarkW



Mark,
You crack on with your thoughts on the Compound engine, although I would recommend that you go for the Launch engine as it's self starting and more or less the same engine.

If you are considering a Mill I can recommend the one that I have.
It's a mill/drill and bought from Chester machine tools and it's called the Conquest mill/drill, Chinese import but it does all that I want at a reasonable price.
I originally had the smaller one ,the Cobra but found it just a little to light.

Have a look  (http://www.chesteruk.net/products/detail/500  )

Hope this is of help.

George.


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