Werowance attempts Myfordboys traction engine

[werowance]

I just received my castings and instructions for Myfordboys traction engine.

not that i am experienced with machining castings but to my untrained eye they appear to be very good quality.
the blueprints are the type i like with only 1 or 2 parts per page with multiple view points of each part that need multiple views.

downside to me is that the fasteners are all BA and not standard (standard to me anyway) and some of the metal types i do not understand. for an example (which i do understand) is it calls for "silver steel" to me in the USA that is "Drill Rod" but for another piece it calls for "BMS" which i am assuming some sort of just regular steel but i dont know...

at any rate, firs questions are:

1. does there exist some sort of chart that would recomend substitutions for BA thread to standard theads? something like 4ba = recomended substitution is 4-40 threads?
2. what is "BMS" metal?
3. any good sources for (edited out size ) copper tube for the boiler in the USA? i do understand tube not pipe (we dont want a seam running the length of it that could split open)

other than that it seems pretty straight forward at first glance of the prints. im sure ill have plenty of questions once i get started but im just now at the reading and sourcing materials point right now

 

[fcheslop]

BMS= Bright Mild Steel= EN3B
Ive attached a thread chart
Not sure what size domestic/industrial plumbing pipe available in the USA over here it would be a metric size at 54mm.
Good luck
cheers
frazer

 

[werowance]

Thank you fcheslop. Bright Mild Steel - would that be like 12L14 leaded steel? or what would that be called in the US?

 

[fcheslop]

SAE1021

 

[werowance]

oh, that seems to be generic cold rolled steel pretty much would that be correct? the parts its going into don't seem to need to be anything special but would like to learn the lingo a bit better

 

[fcheslop]

Would have thought soo its just a general mild steel no added lead
We have a Black mild steel and a Bright just to confuse matters
Did you buy his gears as they are very cheap?
Keep well

 

[werowance]

no i have not. i sort of enjoy making my own gears, that said i have ruined several gears on other builds before i got a pair of suitable ones. but in the end i may have to purchase his but thats a good ways off for me just yet.

 

[fcheslop]

Some more info on the site in the link
Just use google if needed to translate
I like cutting my own gears but will admit to having the odd 64and a 1/2 toothed one
Steam45 - Presentation - engine

 

[werowance]

post deleted because it gave to many of the sizes in the plans

 

[fcheslop]

Add double wall to the ID
What is the designed safe working pressure? of the boiler?

 

[werowance]

post deleted because it gave to much information on the size of the boiler in the plans

 

[fcheslop]

Glad you have it sorted
The thicker tube maybe an advantage when fitting the smoke box rivets
2inch 20 swg is still available not that it matters
cheers

 

[werowance]

still sourcing some of the materials. on the bushes for the safety valve, steam pipe etc on the boiler it calls for "bronze" without secifying any alloy for that. i understand that brass would "leech" and is not considered good for boilers. so my question is what alloy or type of bronze am i looking for? i see phosphor bronze, aluminum bronze, silicon bronze, bearing bronze etc. and none of its cheap either. so what alloy would you all recomend for those bushes?

 

[fcheslop]

Phosphor Bronze. NOT SAE 660 or any containing lead

 

[werowance]

well, c510 bronze on some sites dont show it contains lead at all but then some say it might contain .05% lead as its limit of lead but its nominal composition is 0% lead
then i find (and i know its not phosphorus) 655 silicon bronze. no lead and recomended for marine and high corosion environments.

would either of these work ok?

 

[fcheslop]

PB102 is the UK spec for the one I have used I think? I tend to just ask m-machine for some bronze to make boiler bushes
Some of the grades dont silver solder well. The leaded ones are poor although most may have a very small lead content. The Aluminium Bronze grades are difficult and some times impossible to silver solder or at least thats my experience

PB102	CW451K
C51000	DEF STAN 02-838
NES 838	ISO CuSn5

Mechanical Properties (specification minima 18mm to 40mm dia)

Tensile Strength	460N/mm²
0.2% Proof Stress	380N/mm²
Elongation	12%

 

[werowance]

ok, PB102 is c510 in the USA. PB102 also "can" contain up to .02% lead but nominal on it is also 0% same as c510. thank you so much for that info.

 

[fcheslop]

Good luck with the build
I keep looking at it as a simple build or the Wells traction engine. The Myfordboy one to my mind looks a little more realistic
Keep well

 

[miss_emma_jade]

theres a lot more work in the myfordboy engine. its very nice tho

 

[werowance]

it does seem like a lot of work. his prints do not include instructions however he has a complete build guide on utube from start to finish and some things look like it might be a major challenge for me. that said - cutting cams the first time was a major challenge as well but with enough help and hand holding from folks here i was able to do it and looking back its not that bad now that i have done it.