Steam Tractor 3/4" (Rudy K)

[b.lindsey]

Looks like it should be plenty of heat Kim. As for being too much, guess you wont know will you try it out with the boiler. You can always shorten the wicks more as needed though...better too much than too little in this case.

Bill

[Dave Otto]

Break out the hot dogs!

Kim I ran into this when I made my Poppin; the tube that I used was too small and and I had to cram the wick into it. When burning it would go for a while and then go out and smolder.
I rebuilt the burner using a larger tube and then it burned great.

Nice work on the burner BTW.
Dave

[Kim]

Thanks Bill and Dave,

Nice to know I'm not the only one who's run into these issues before. Makes me feel like less of a dunce I guess 

I probably won't play with the burner anymore till I get the Boiler done.  I'm excited to start that, and a little scared!  Yet another new thing for me to tackle... 

Kim

[b.lindsey]

Kim, my last screw up was on the cap for the Pearl feed pump. I needed to make the 1/2-20 threads a bit deeper, Picked up the tap checked that it was 1/2" but failed to notice that it was 13 tpi rather than 20. Non-recoverable...had to make a whole new cap. Hey maybe we need a dunce cap emoji 

Bill

[Kim]

Hey maybe we need a dunce cap emoji 

Yes, that would be one emoji I could certainly make use of!   

Kim

[b.lindsey]

You and me both Kim!! 

Bill

[Don1966]

Looking great Kim inspite if the problems you encounter your making headway buddy....



 
Don

[Kim]

Thanks Don,
And I figure that the problems I run into indicate that I'm pushing myself to learn new things.  So, while frustrating from time to time, it is really a part of what makes this hobby all so interesting to me too!

At least, most of them... Picking the wrong tap out of the drawer?  Well, that probably calls for the Dunce Cap emoji!

Thanks for checking in!
Kim

[10KPete]

You're not alone there, Kim. I made some parts last year that were tapped 3/8-24, simple stuff. Picked a gun tap out of the drawer and for the life of me couldn't make it cut!! After a few minutes of  I looked at the tap. Really looked at it.

It was a LH thread 3/8-24.......  Hell, I didn't even know I had one!  It's now sitting in a place of honor waiting for a LH thread to be cut...

 

Pete

[Kim]

Thanks for that Pete!
It shouldn't make me feel better to hear other people's difficulties, but you know, it does 

Thanks to all for your commiseration,
Kim

[Flyboy Jim]

You're not alone there, Kim. I made some parts last year that were tapped 3/8-24, simple stuff. Picked a gun tap out of the drawer and for the life of me couldn't make it cut!! After a few minutes of  I looked at the tap. Really looked at it.

It was a LH thread 3/8-24.......  Hell, I didn't even know I had one!  It's now sitting in a place of honor waiting for a LH thread to be cut...

 

Pete

Pete.............this sounds like a new version of the old problem of a "solution looking for a problem"! 

Jim

[10KPete]

Yes, Jim, I have a shop full of those!!

Pete

[Kim]

Today I started on my first boiler journey.  I’m excited about this – I’ve been looking forward to the boiler since I started working on this model.  The gears were pretty intimidating, but this seems a little more so.  But exciting never the less.

So, nothing to do for it but get started!   And I did this by cutting copper tube for the main part of the boiler.  The longer half that is still clamped in the saw is the piece we’ll be using for the boiler.


On the lathe, I faced off both ends so they were nice and square, and got it to the 8” length.


I blued up the outside of the tube, and used the paper trick to layout markings on the tube for the quadrants.


Then marked the holes for the steam outlets and the boiler tubes.

For the steam outlet bushings, I drilled 3/8” holes.  I have not worked in copper much and have heard it can be very grabby.  So, I step drilled starting at 1/8” in 1/16” increments up to the final size.  That may have been over cautions, but it worked well and I never had any grabbing issues.


For the boiler tubes, I drilled 3/16” holes at the end:


And about 2/3 of the way up:


All the holes are in the boiler tube now.




With the holes in place, I then bent the holes for the forward boiler tubes back so that the tubes can come at the correct angle.  I did this by annealing the copper and using a piece of 3/16” steel rod to bend the boiler tube.  It took several rounds of annealing and bending to get the angle steep enough.


Here’s a close up of the bent tube holes.


And here I’m comparing it to the diagram – looks pretty good to me!


In the top picture here, you can see what I’m going for – the boiler tubes are external in this boiler, and add surface area close to the heat source.


Next, I’ll work on the bushings and boiler tubes.
Thanks for checking in,
Kim

[Kim]

SAFETY QUESTION:

Here's a question I need help with.

I've heard many people say not to do boiler tests with air, ONLY use water!  And I understand the reasoning is that a catastrophic failure with pressurized will be less dramatic than with Air.

However, in the instructions from Rudy on this boiler, he describes using air to test the boiler.  Granted, the initial test is only at 5 PSI, which might not be too bad - just looking for any obvious leaks. But the final test is at 60 PSI (this is a 30 PSI boiler, so 2x is 60).  His description is to use a bicycle pump and a "sniffler valve" (is this a check valve?) and pump the pressure up to 60 PSI.

Is that a reasonable thing to do? Or was this written before safety was invented and people didn't care as much if they lived or died when testing boilers?

It would be nice to just use a bicycle pump, because I have one of those.  I'd have to build a water pump, and that will take time and planning.  Clearly something that's worth while for safety's sake.  But I wanted to ask for advice here.  Would it be overly foolish to follow the book's description and use air for a 60 PSI boiler test?

Thanks,
Kim

[fumopuc]

Hi Kim, If your final decission, after hearing all other opinions, will be the hydraulic way, this little pump is available in the US.
https://www.pmmodelengines.com/shop/steam/boiler-feed-pump/