Building a 31/2" Gauge Locomotive Engine

[sbwhart]

Thanks for you comments and engouragement chaps

Stew

[sbwhart]

Ok Chaps

Got the case hardening powder, to case harden the links from Chronos, this is it.



For thos of you who don't know about case hardening what its about is soaking the mild steel parts in a carbon rich environment at about 900 to 1000 deg C, what happens is some off the carbon soaks into the skin of the steel so you get a hard skin on it, this process has been used for a over a 100 years so its not new.

Just one word of warning some of the old case hardening powders had cyanide in them and other nasties so only use stuff that is new and you know is ok.

This is what you do.

I wired the bits up so it was easy to pick the bits up with pliers.

Made up hearth so that it formed a little cave so that it would get good and hot.

Before you start to get things hot make sure you got no inflamables about you don't want to set your self on fire 

With a gas torch  heat them up to a nice orangy red its better to do this in natural light so you can se the colour.



When you've got each bit up to temperature cover them in the powder a leave them to cool.



When cool take them out of the powder and heat them up to orange again and hold at this temp for about five minutes to burn more of the carbon in, then quench in water.

Her we are job done



At this point sods law struck whilst I was taking the wire off and cleaning one of the links up the darn thing sprung out of my hands and landed some where in the shop, I looked and looked and couldn't find it.

At this point I went and got the boss with a torch, she's a fan of CSI, how come Grisome and Nick Taylor can find a pin head of blood that catches the baddy and we can't find a bloody loco link.

At this point I was P****d off, the boss said that the only way to find it was to stop looking for it, sound advice I thought, so I started to make a vice stop, it still didn't turn up, tonight had another look for it,

Boss said is it in this bucket with all the metal shavings,

No that too far away,

 I'll have a look any way she said, ho is this is 
 


Well alls well that end well.

Have fun

Stew

[Divided he ad]

Sounds like you've been having fun Stew      

Always look where there is the most metal to cut your hands.... That's where it always lands!!!


Looking good.... U sure you won't have it finished in a few months? ..... Looks like your storming ahead 



Don't know if I've said this already but just in case... Thank you for the hammers   
Not that I've had chance to use them yet!! First time in the shop for weeks and I was re-soldering the water feature light!! 


Anyway, won't be long now.... Got one of the diff's for my mates landy tonight (off a scrap one!) and the other is coming next week..... just a few more nights taken up and stopping workshop progress! ..... Not that that's anything to do with a loco build     




Won't be long to the running chasis now eh?   





Ralph.

[sbwhart]

Hi Ralph

I was wondering where you'd got to, John said this was a busy time of year for you  ,

Thanks for the loan of the mould for the hammers, and the tube for the handles is just great  .

When I've completed the loco reverser I need to make a handle for it I can either buy a casting or make from bar, I'm making from bar, so I need to get some kit made for my RT, so the loco will be put on the back burner for a week or so.

Have fun and don't work too hard.

Stew

[sbwhart]

 

Ok this is a bit off topic but a few post back I said I was making a vice stop, well its finished I based the design on Johns excellent thread her http://madmodder.net/index.php?topic=1007.0

So this is my attempt



Yet another job ticked off that will improve my little shop 

Have fun

Stew

[bogstandard]

Very nice indeed Stew.

Are you living in that shop or what?

It looks like you have got some sort of production line going, banging out bits all over the place.

John

[sbwhart]

Thanks John

What I'm finding it that as I add to my tooling, bits get "easyer" and quicker to make.

And I also find that I notice and learn a lot from my visits to you. 


Stew

[sbwhart]

Hi Chaps

Finished off the reversing frame this afternoon. It was just a matter of turning up and riveting a pin to the frame and a final bit of fitting.

This is the frame with the arm to the left



And to the right



The toolmakers clamp is just there to give a bit of purchase to the screw.

It just needs a bit of cleaning up not to much bling mind as its to be painted Blackberry Black

I've got a chose with the handle buy a small casting or make from bar stock, I'm going to make from bar stock its just like making a small fly wheel and whilst I'm at it I'll make the rest of the handles needed, but before that I've got to do a bit of work on my Rotary Table.

Off to a pop concert in the forest tonight

Rock on Modders   

Have fun

Stew

[sbwhart]

Now that I've got my RT sorted I'll make the winding handle for the reversing gear.

First job turn up a blank 25mm dia by 5 mm thick, trapand a the front face, same as for the small handles, centre drill and drill 2.5mm



Remove chuck and job off the lathe and mount on RT, centre RT an the quail axis simply by having it lose put a centre in quil wind it down onto the job and let it pull RT central tighten RT zero X and Y axis. Job Done



Off set the X and Y the correct amount then nice and steady and methodicaly drill the corner holes 2mm.



Then with a 1/16 burr take out the meat to form the spokes.



Mount the chuck back on the lathe, give it a bit of a polish, and part it off



Clean the spokes up with a file, make a handle and silver solder it to the wheel.

Thats it the reversing gear completed.



I'm going to start on the other end now the cross head and the slide bar and the motion frame

Have fun

Stew
 

[bogstandard]

You're really enjoying that swapability between the lathe and RT aren't your Stew?

Now you know why I had been meaning to do it for ages.

Lovely bit of work there, no holding you back now.

John

[sbwhart]

Hi John

It really makes set up quick and easy  its the best way to go if you're going to do a lot of RT work.

Stew having fun

[Bernd]

Nice job Stew.

I really like that small hand wheel, looks nice. 

Now you got me thinking about a mod like your rotary table too. Marked on my "round-tuit" list. 

Bernd

[sbwhart]

Now you got me thinking about a mod like your rotary table too. Marked on my "round-tuit" list. 

Bernd

Its nice to know I'm infecting some of you Guys with 
 


Have fun

Stew

[sbwhart]

Made the motion frame today, its fabricated from mild steal 3/16*5/16 section.

This is how it will be frabricated the screws are there just to keep things in place whilst it silver soldered together.



First job cut to length +2mm for cleaning up, square one end up then bring the other end to size.

To drill the holes for the screws, I used my parrallel stop to get things square and to keep holes in the corect position to each other.

Drill the short length for threading  8BA.



Drill the long length clearance on 8BA



I didn't deburr the holes so that the parts would screw up and leave a small gap for the solder to penitrate.

Silver solder and clean up, that it job done.



And this is where it will fit between the loco frame



Have fun

Stew

[shoey51]

great work there Stew

[SPiN Racing]

Coming along real nice Stew!

[sbwhart]

Made some more bits this week:- the lever and the mounting brackets for the lifting block, and the couplings for the valve rods.



The lever and bracket are similar to other bits I've made so I wont go into any detail, but the coupling were a nice interesting little job, the instructions call for them to be made from 1/4" square bar, but I thought it would be easyer to make them from round bar and mill them square, this is easy if you've got a mill.

To work out the start diameter you use Mr Pythogoros's theorem, then its just a mater of turning the diameter to size with a length long enough to make the two couplings:- turn a 1/4" diameter step in one end and drill and tap 5/32*40 ME turn, part it off, turn it round and do the same to the other end.

Then sit it on a parallel in your mill vice, touch down on the top with the cutter, and mill off 1/2 the difference between the diameter an 1/4" zero your dial/DRO, flip it over 90 deg and mill another flat to the same zero, so what you've got is two flat at 90 deg, flip it over 90 deg and take off the  other halve of the difference, zero thing up, flip it over another 90 deg, mill down to the zero, and youre left with a nice bit os square bar.





Next ops are to drill the cross hole and mill out the fork, this is where the mill stop comes into play.

Set the mill on the Y centre line of the square bar, put the job in the vice put a parallel on the top of it and tap it level with the top of the vice, set it up in the correct Y position, adjust the stop so that its, touching the job, centre drill then drill 1/8" take the first one out of the vice, set the second up against the stop drill that the same, take it out flip it over 90 deg adjust the Y position and again drill it 1/8", repeat for the other one this time you leave it set up change the drill for a 1/8" slot drill and mill out the fork, take the job out put the other one in again up against the stop and mill that one out.





Thats it Job done the mill only needed setting up the once and both parts came out exactly the same.

To finish off file a 1/8 rad with a filing button and give it a bit of a debur and a clean.



And this is where they go



I do enjoy doing little jobs like that 

I've only 4 or 5 bits to make before I'm ready to start assembling the valve gear to the loco, and try getting it running on air, fingers crossed.

Have fun

Stew

[Bernd]

Very nicely done Stew.

That piston/valve unit looks like a nice tight little package for a steam engine.

Bernd

[Darren]

Nicely shown there Stew, result looks perfect.

I'll be refering back to this post later  

[Brass_Machine]

Wow... that is looking pretty good there Stew!   

Eric

[Divided he ad]

Tidy bit of work there Stew.... Do I smell a little video in the near future? 




Ralph.

[sbwhart]

Tidy bit of work there Stew.... Do I smell a little video in the near future? 

Ralph.

As long as it runs 

Stew

[shoey51]

wow Stew that is looking lovely cant wait to see it running

[Stilldrillin]

Great job there Stew! 

But, looking at the pic with your 6"rule, I wondered how many part finished items I would have hiding around the workshop floor....... 

Fiddly diddley parts, teamed with fumbly fingers. Not a good combination...... 

Blummin well done mate! 

David D

[bogstandard]

Stew,

After your visit yesterday and your explanation of what you have been getting up to, and now seeing the results, is showing me that you are enjoying yourself just a little bit too much.

My suggestion would be to do a bit of manual hacksawing thru a 6" bar of cast steel, that just might knock that damned smile off your face.

Lovely work as usual.

Bogs