K-27? lets hope so

Got your image - thanks!  Looked through it and compared your drawing to Kozo's. It was hard to figure it out since your drawing had dimensions in different places than his, and after following through and doing the math to compare them, I found it was quicker for me to make a new drawing in Fusion using his dimension order.

And, nope, it does not work for me either! Something has to give, in those dimensions, it just does not add up. So, I don't think its you, I think Kozo made an error in it. The key would be deciding which things are critical to function, and which dimension is not that important. I would say that the 2mm radius/4mm offset are not critical, it looks like that is just an opening in the side of the part, and unless some other part I am not aware of bears on those edges, then just pick one to change and move forward with it.

I agree with Chris.  That opening isn't a critical dimension.  Just make it look good.  Keep the 4mm parallel dimension and the 4mm diameter but move the center of it out a bit.  Or, keep the 4mm diameter in place and move the outer lines in slightly to make them tangent to the 4mm circle.  In either case, you'll have to adjust the rear radii to match.  Just make it look pretty!

Kim

Quote from: cruebyGot your image - thanks!  Looked through it and compared your drawing to Kozo's. It was hard to figure it out since your drawing had dimensions in different places than his, and after following through and doing the math to compare them, I found it was quicker for me to make a new drawing in Fusion using his dimension order.

And, nope, it does not work for me either! Something has to give, in those dimensions, it just does not add up. So, I don't think its you, I think Kozo made an error in it. The key would be deciding which things are critical to function, and which dimension is not that important. I would say that the 2mm radius/4mm offset are not critical, it looks like that is just an opening in the side of the part, and unless some other part I am not aware of bears on those edges, then just pick one to change and move forward with it.

That makes me feel better :-) cheers

Quote from: KimI agree with Chris.  That opening isn't a critical dimension.  Just make it look good.  Keep the 4mm parallel dimension and the 4mm diameter but move the center of it out a bit.  Or, keep the 4mm diameter in place and move the outer lines in slightly to make them tangent to the 4mm circle.  In either case, you'll have to adjust the rear radii to match.  Just make it look pretty!

Kim

Will do thank you, onwards and upwards :-)

Some drawings done in cad now so i have a much better understanding of the loco, i have got the lathe ready and the mill trammed in just waiting now for some materials to arrive.

Ordered 10mm s275 so i will face that down to 9mm.

You know that you see these locos on forums and tv etc etc and you wait until you a) have the funds b) the skills c) the time or d) all of them but i dont think i fully realised just how much prep work goes on before you even make a chip, i can certainly say its opened my eyes and the respect for those who have built and or building live steam or come to it any model engineering just got even more.

Malc

After making an error of judgement making the previous set of axle boxes i scrapped all 8 which were in brass.
In a way i am not overly disappointing because i decided to try to do a trial in cast iron as many people seem to recommend this for axle boxes.
So i made 2 and instead of splitting in half i made them as 1 piece which meant trying to cut some grooves for the top half for oil ways.
As i have never used a rotary table i got it a bit out of alignment so glad these were a trial to learn on material and rotary table.

Do anyone see any reason why i should not do 8 like this (more accurately of course) for this loco, i  am just not sure as it does not have an oil bath in the bottom and will rely on just what gets fed into the top

Many thanks Malc

Hi Malc,

New to M.E. but not making and repairing things. Call me strange but I find "reading" engineering drawings a relaxing pastime. In this I am not alone on this site (Ay Chris?). As I have never built/run a loco, I should probably advise taking this with a small pinch of salt, but the wool tips come from helping out on full size traction engines.

In his K27 book Kozo says on pg28 2. last paragraph "the pocket in the bottom half is packed with oiled yarn to lubricate the journal"
This yarn stuffed oil pocket is very important. A wad of natural untreated Worsted wool (your lady wife will know) is like a sponge and a wick at the same time. With out it oil poured in the top pocket will seep down around the axle and leave the scene all to quickly. With it oil will run into the bottom pocket and be sponged up by the wool. If the wad of wool reaches the pocket bottom it will wick oil up, if it sits slightly proud at the top of the pocket (touching the axle) it will wipe oil on the axle continuously. Don't make the wad too dense, it's the air space between the fibers that makes it work.

On pg35 fig 2-13 he shows an oil groove on the axle making the one in your block redundant.

Pg43 fig 2-32 right shows the Crank/Counterwieght is loctited in place during centering. A one piece block would need to go on first, maybe creating a risk of the loctite gluing the axle to the block?
If you drive your completed engine allot you may, many years and many miles "Down the Track" wear the axle block bores into an oval, requiring replacement. With the cranks/counterwieghts loctited on I suspect you would be glad of two piece blocks.

Malc, I have clicked the notify button and will follow (piggyback!!) your learning curve, Kozo's book in hand, with great interest.

Hi Brett, thanks for response, i'll put my bits in yours :-)

Quote from: Fj45 Hi Malc,

New to M.E. but not making and repairing things. Call me strange but I find "reading" engineering drawings a relaxing pastime. In this I am not alone on this site (Ay Chris?). As I have never built/run a loco, I should probably advise taking this with a small pinch of salt, but the wool tips come from helping out on full size traction engines.
I love drawings too and technical books especially but i really struggle to read some of it and understand some of it but that does not deter me

In his K27 book Kozo says on pg28 2. last paragraph "the pocket in the bottom half is packed with oiled yarn to lubricate the journal"
This yarn stuffed oil pocket is very important. A wad of natural untreated Worsted wool (your lady wife will know) is like a sponge and a wick at the same time. With out it oil poured in the top pocket will seep down around the axle and leave the scene all to quickly. With it oil will run into the bottom pocket and be sponged up by the wool. If the wad of wool reaches the pocket bottom it will wick oil up, if it sits slightly proud at the top of the pocket (touching the axle) it will wipe oil on the axle continuously. Don't make the wad too dense, it's the air space between the fibers that makes it work.
This is really valuable info thanks, if  i go this route thats some learning for me

On pg35 fig 2-13 he shows an oil groove on the axle making the one in your block redundant.

Pg43 fig 2-32 right shows the Crank/Counterwieght is loctited in place during centering. A one piece block would need to go on first, maybe creating a risk of the loctite gluing the axle to the block?
If you drive your completed engine allot you may, many years and many miles "Down the Track" wear the axle block bores into an oval, requiring replacement. With the cranks/counterwieghts loctited on I suspect you would be glad of two piece blocks.
I dont see myself running it around tracks too often, i love the build of items more than when its finished but i would love it to work as it should then i'll put it on the dresser for viewing and run it occasionally when the grandchildren visit around our small garden

Malc, I have clicked the notify button and will follow (piggyback!!) your learning curve, Kozo's book in hand, with great interest.
At my rate this could be a long journey and i hope you can get into it too :-)

So its finally started.
The first bits i have ever machined up like this, i cant explain how it feels to hold them knowing it was a big achievement for me, but most of all it should now motivate me to tweak the axle boxes just a teeny bit better then onto some frames.

Great start, nice looking set of parts! 

Great looking parts!  Good start indeed! 

Kim

Thank you kim & crueby

I have a question:
In uk locos they have stretchers along the frame length but there seems to be nothing in the k-27 so what keeps the frames apart in its set positions?

I do not have the K27 book, I  built the New Shay, which had a full length frame. Kim?

Following, great start! 

I dont have access to my books at the moment, but will look in a few days.

Kim