drawing help

[BrokenBiker]

trying to move some drawings from a very hectic PDF into fusion so i have individual drawings for each component and a CAD model to refer back to as well.

problem is, on a few components you get shown a 3d image of what the component is, then a drawing split into various views...but some of these drawings arent too forthcoming with dimensions. most of them ive been able to work out from other hole locations or given dimensions, but this one has me scratching my head.

the dimension i need is the thickness of the bronze bushing, that is pressed into the (green) housing. i have diameter and bore dimensions, but not the thickness. any ideas on how to determine this otherwise its going to have to be a suck it and see type of deal when i get round to assembly and given its likely going to be sub 10mm thick, re-chucking to skim could be interesting

 

[Screwdriver]

Looks like 8mm to me. That's a guess of course, do you have the drawing(s) for the part(s) that fit into the bushing?

 

[My Old Landy]

Looks like 8mm to me. That's a guess of course, do you have the drawing(s) for the part(s) that fit into the bushing?

I was just typing the same response!

 

[Agroshield]

Print the drawing out and scale it from the other pieces. You do not need a ruler. The ID is 8mm so make two marks on a piece of paper and see if the bush length matches those two marks.

Use a pair of compasses set to the 4mm radius of the 8mm diameter. Check on the plan view stabbing the point into the centreline.

 

[BrokenBiker]

Looks like 8mm to me. That's a guess of course, do you have the drawing(s) for the part(s) that fit into the bushing?

i have drawings for individual parts that make the crank shaft, havent looked much further yet as there are 46 individual components to make and im still trying to get my head round how small most of them are. there are about 5 components that go together to make the crankshat sub assembly so the maths would stack up to make the dimension i need, providing the needed dimesnions are there.

i also used the 'looks like 8mm' method when putting it in cad but its bugging me that there isnt a dimension attached to it

 

[Onoff]

Grab an ordinary rule and zoom your phone pic until a known dimn lines up. Then measure the bush.

 

[Agroshield]

...it's bugging me that there isn't a dimension attached to it

You could contact the drawing's author, ask them to revise the drawing and re-upload it.

Many drawings from the model engineering/model engine world are not to the same standard as a professional one that has (in theory) been drawn by person A and checked by person B.

You are doing the correct thing by re-modelling it yourself as checking it all fits together in the computer is cheap. You also have to check it can actually be assembled, which is sometimes less easy.

 

[BrokenBiker]

You could contact the drawing's author, ask them to revise the drawing and re-upload it.

Many drawings from the model engineering/model engine world are not to the same standard as a professional one that has (in theory) been drawn by person A and checked by person B.

You are doing the correct thing by re-modelling it yourself as checking it all fits together in the computer is cheap. You also have to check it can actually be assembled, which is sometimes less easy.

im fairly confident it can be assembled as ive seen models made form the same drawings, im only really remodelling it in CAD because all the compomnents are shown on 1 sheet and its very chaotic. i just wanted individial drawings for each component really as its going to be made over a good few weeks as and when i get the spare time and materials...

its a drawing for a horizontal potty mill steam engine. the drawing i have was drawn in 2014 by a guy in new zealand so contacting may be more hassle than its worth.

 

[BrokenBiker]

so, after using a rule and zooming in it does look like its 8mm. the drawing does state it is scaled 1:1 on a3 so fairly confident , but when i get round to the components that make up the crank i will do some maths and determine the spacing needed between the bushes compared to the spacing between the bushing housings and work it out from there

 

[Agroshield]

The draw-er, Julius, is still alive and kicking:

valveless steam engine

He has a bit of a reputation for this, hence the caution on assembly.

 

[Misterg]

...a very hectic PDF

Blimey! You weren't kidding!

https://modelesavapeur.com/telechargements4/h-potty-mill-engine-09-02-08.pdf

(Crank ends up as 22mm wide, and there is what I assume is one of the M8 washers either side (last item on the list??), so a tad over 23mm space required. The holes for mounting the crank supports are on 32mm centres, leaving ~9mm to account for half the width of each bearing, so if you made them 8mm each, it would leave ~0.5mm float either side of the crank, depending on the exact thickness of your M8 washers. Sounds about right - steam engines like things sloppy )

 

[BrokenBiker]

The draw-er, Julius, is still alive and kicking:

valveless steam engine

He has a bit of a reputation for this, hence the caution on assembly.

fair few drawings there, all seem just as chaotic as the one i have

 

[BrokenBiker]

Blimey! You weren't kidding!

https://modelesavapeur.com/telechargements4/h-potty-mill-engine-09-02-08.pdf

(Crank ends up as 22mm wide, and there is what I assume is one of the M8 washers either side (last item on the list??), so a tad over 23mm space required. The holes for mounting the crank supports are on 32mm centres, leaving ~9mm to account for half the width of each bearing, so if you made them 8mm each, it would leave ~0.5mm float either side of the crank, depending on the exact thickness of your M8 washers. Sounds about right - steam engines like things sloppy )

cheers for that, saved me doing the same thing when i got to those bits

when i first opened the pdf my eye twitched...took a fair while to be able to clear the fog and see what was what...hence the immediate desire to put it all in cad as singlular drawings...plus i can then open them on my phone and zoom as and when while im in the shed without needing to take the laptop with me

 

[ajlelectronics]

My verdict is also 8mm.

 

[knighty]

if you're happy the drawing is to scale... then it's 8mm

cut and pasted the 8mm bore diameter from below it on top if it, lines up perfectly

 

[BrokenBiker]

if you're happy the drawing is to scale... then it's 8mm

cut and pasted the 8mm bore diameter from below it on top if it, lines up perfectly


View attachment 499058

happy is a slight stretch at this point, but it does state on the 1st page that drawings are 1:1 unless stated...ive found a few more missng dimensions as ive been looking though, most can be easilly determined from others, but some take some thought and looking at what is going to moun there and its relation to something that mounts elsewhere, some can be determined from cad once the rest of it has been put in....im sure it will all come together in the end and ive just relised im ordering a 300mm length of bronze and these bearings are 8ish mm so if its wrong, i will just turn another rather than try and take a skim

 

[iNf]

A clearer drawing. ( can you attach a pdf to a post?) I can email you the pdf if you want ?

 

[daedalusminos]

What an advert for JDW Draughting Services - doubt I'll be contacting them anytime soon!

 

[BrokenBiker]

A clearer drawing. ( can you attach a pdf to a post?) I can email you the pdf if you want ? View attachment 499079

That would be brilliant, thanks, I shall pm you an email address.