Finishing off an engine to get it looking right

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B

Bogstandard

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I am just going thru my build of a mine engine and came to a bit where a post here would be better than in the build post.
When I build an engine, I do like the nuts and bolts to look correct for the engine, on this one I am doing all hex head nuts and bolts.
This is how I get studs and nuts looking correct.

studs1.jpg


This first picture shows what I am about to assemble. These bolts (8BA normal on the left and one size smaller head on the right) look way too long, but there is a reason for this. I am a cheapskate when it comes to buying things so I buy the longest bolts possible (only pennies difference) and make a dual use of them. The other thing is that when drilling clearance holes on a close tolerance part like the steam valve I don't drill using the standard sized clearance drills, but measure the thread and use the next sized drill up, this keeps everything nice and tight.

studs2.jpg


On this one the bolts have been tightened to the bottom of the holes with two washers under the nuts, with the 'good' end of the nut towards the washers.

studs3.jpg


Now this is where being a cheapskate comes into its own, the tops of the bolts I have cut off will be used elsewhere on the engine. Two bits for the price of one.

studs4.jpg


Sorry about the blurred pic, it must have been the knee trembling excitement.
Anway, what I have done is machine the cut off threads and nuts to a thickness that looks right for the scale of engine, in this case about 1/3 of the nut was removed.

studs5.jpg


Take off the nuts, remove one washer and put the nut back on the right way round. The finished result, with the same length protruding from each thinned down nut now looks right, and when this is done on all parts of the engine it just 'lifts' it above the norm.

John
 
Very good info. and I must say it gives it quite a nice look. I am putting hex heads on the shoulder bolts that go in the mini mill engine I'm building
Julian
 
Hi Julian,
This isn't just for cosmetic look, it is also the way it should be assembled.
On the full size machines they used studs and nuts to allow the heavy castings to be placed into position without having to support all the weight in one unit while a bolt was put thru. Just like anywhere an article was assembled with nuts and bolts, if it was in a horizontal plane the bolts if possible would always go down into the hole, so if the nut fell off, at least the bolt was still in position.
When you look at the full sized engines you start to realise just how well thought out they were, and very ingenious in some of the methods they used considering the materials and machinery (or lack of it) they had at their disposal.

John
 
Good Stuff there John.

I also like your steam chest profile!
I think that looks better than the round ends.

Rick
 
Hi Rick,
You like the profile then.
The only reason it is like that is because I hate four jaw work, its not that I can't do it , it is just at the moment it is difficult for me to do.
The whole lot was done on the miller, the only lathe work was the operating rod and the gland nut.

John
 
I undersand hating a 4 jaw. Mainly because mine is a piece of......
Well I need a new one!

Rick
 
Where do you buy your hardware from ? I need some 6-32 nuts and the hardware variety are too big.
 
I am lucky in that in the UK, BA was adopted fairly early on in the model engineering field, plus for many years it was the standard for electricians in industry, hence we can get everything we want here, at a price. The smaller you go the more expensive.
Where you would obtain such nuts and bolts in the States I have no idea, maybe one of the local lads can help.

John
 
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