Steam Tractor 3/4" (Rudy K)

[Kim]

Kerrin,
Glad the popcorn is coming along well!  You're going to need a lot of that to keep up with all the builds going on right now!

Terry,
So, you call it a Chimney rather than a Smoke Stack?  To me, a chimney sounds like something that is stationary, but I don't really know.  Wonder if it is a geographical terminology difference?
Likely, I will continue to call it a smoke stack, since that is what the plans say.  But I'd love to hear what others think the correct terminology is.

-------

In this installment, I finish up the Smoke Stack (or the Chimney?) and start off on the door to the Smoke Box.

All I had left for the Smoke Stack was mounting it on the Boiler Casing. So, I lined it all up, very carefully and transferred the hole locations to the Boiler Casing.  Then I removed all removable parts from the Boiler Casing and mounted it on the mill where I drilled, and tapped for 2-56.


With that done, I polished up the Smoke Stack and attached it with four 2-56 bolts.


I think it looks pretty good there


The Smoke Box Door started as a piece of 1/4" 1018 steel.  I needed to bring it down to only 5/32” in width.  But before I started to shave down the width, I attempted some ‘stress relief’ by heating the steel up to nice red hot for a while, then letting it cool slowly to room temperature.




While it was cooling, I started on a radius tool to use on the outside edge of the door. I needed a 3/32” radius.

I used a length of 3/8” W-1, since that is what I had available.  I squared up one end, holding it in a 5C collet block (well, I only squared up 3 sides, I didn’t bother with the bottom).  Then I tipped it up by 10 degrees and cut a relief angle along the front.


Leaving it tipped at 10 degrees, I then rotated it by about the same to provide some relief in the side direction. And, with a 3/16” end mill I formed the 3/32” radius, like so:


I didn’t get any pictures of this, but I also cut a flat on the bottom and top of the radius tool, to help it sit well in the tool holder, and then heat treated & tempered the business end of the tool.

By this time (must have been several hours later) the stress relieved steel was quite cool.  And the stress relieving process had warped the steel  – a bit of a potato-chip shape.  But that was the point, right?  By relieving the internal stresses now, you release that stress now while you still have time to deal with any warpage.  So I’m claiming that my stress-relieving process did its job! 

I mounted the steel in the mill and shaved off one side to make it flat.  There was a 25-30 thou difference in height across that face.  Then I flipped it over and did the same to the other side.


After that process, the steel was quite flat (as tested on my layout block), and didn’t seem to be warped any more.  I still have a little more to remove to get to the desired thickness, but I’ll do that on the lathe (I think).

Finally I took a scrap piece of 2” Aluminum round bar from my scrap box, faced off one end nice and smooth in the lathe, and used LocTite to glue the steel onto this.  I’m going to try turning the steel like this.  We’ll see how that goes.  But for now, this is where I stopped, waiting for the Loctite to set.

Here it is with my Sine Vice sitting on top of it to keep them together while the Loctite sets.


Thanks for checking in on me,
Kim

[10KPete]

Lookin' good Kim! That smoke duct looks just right. Very handsome.

I would strongly suggest grinding the corners of the square off and get as close as you can to the desired circle before trying to  turn it. Actually, I would have pressure chucked it...

Pete

[Flyboy Jim]

Looks like a successful day Kim.

That's interesting how much warpage you had. Do you think some of that might have been from applying heat from one side? I remember cutting 1/8" steel with a torch when I rebuilt a steel Commercial Salmon Troller I owned. It warped like crazy. I ended up cutting the rest of it with a Sawzall using metal cutting blades.

I've sure learned a lot seeing you making your own cutting tools. Wouldn't hesitate to do it myself now.

Jim

[Kim]

I would strongly suggest grinding the corners of the square off and get as close as you can to the desired circle before trying to  turn it. Actually, I would have pressure chucked it...

Yeah, your right - I should have knocked the corners off already!  I'll have to cogitate on how to do that now that its glued like that.
As for the pressure chuck, I considered that too, but I wanted to be able to face one side of it, and I couldn't have done that with something on both sides. (unless I'm misunderstanding what you mean by 'pressure chuck'.  I was going to put something up against the other side with the tail stock while I rounded the corners regardless.

That's interesting how much warpage you had. Do you think some of that might have been from applying heat from one side? I remember cutting 1/8" steel with a torch when I rebuilt a steel Commercial Salmon Troller I owned. It warped like crazy. I ended up cutting the rest of it with a Sawzall using metal cutting blades.

Possible, but I don't really think so, since I did turn it a couple of times while keeping it hot.  (I soaked it nice and red like that for 10 min or so based on what others have said in the past.)   Also, I've done this a couple of times WITHOUT the stress relieving step and have found that when you take metal off of one side it does that potato-chip maneuver.  Then you turn it over and try to do the other side and warps in a different way, but doesn't go back to flat, it just gets more contorted.

I believe the heating relaxes things so that the stress that was squeezed into the metal when it was formed has a chance to unwind some. Like I said, I've tried it without the heating and have had very poor experience that way. This way (heating first) has given me much more predictable results!  Others with more experience can comment here, but this is what I've found works best.

If there are better ways, I'm all ears!
Kim

[10KPete]

Ah, face both sides, got it! Pressure chucking would not have allowed that.

The stress relief you did was just how I would do it. I love potato chips, just not metal ones...


Pete

[Kim]

Continuing where I left off with the Smoke Box Door...

As Pete mentioned, it would be a good idea to knock off the corners of the steel plate before I tried turning it.  So I did.  Turns out it wasn’t too hard since the aluminum stub I glued it up to, fit in the vice – just barely, but it fit!


Then to the lathe, to finish rounding it up.


But!  Before I did that, I took an old scrap of steel bar and used it in the tail stock to provide additional support.  Figured this was a good idea for the interrupted cut.


Then I made it round.  It went quite well and it never felt like it was going to come unglued.


Then I moved the tail stock and faced off the front. I took small bites so as not to stress my glue chuck.


Now, at the correct width, I used the round-over tool I made earlier and, well, rounded it over!


Using the parting tool, I turned 1/16” of the back side down to make the registration notch.


After that, I heated up the part to get the Loctite to let go, polished it up a bit, and here it is!


But then my heart sank… It didn’t fit the end of the boiler casing!  I was sure I’d measured it very carefully, but when I checked again, it was 10 thou over-sized, and consequently, wouldn’t fit where it was supposed to


That was the end of last Sunday’s shop session.  And I spent the week thinking about how to get that down to size so it’d fit.  Of course, I didn’t find this till I’d taken it off the glue chuck, and there was NO WAY I’d ever get it centered again.  I could start over, but that seemed sad and painful.

I came up with a couple of options, my first one being to use some double sticky tape to make a feeble glue chuck, but since it wouldn’t truly be centered, I’d thought maybe I could turn it slow-ish and use a file to take down 10 thousandths.  And that’s precisely what I did.  And it worked


And here we go – fits nicely now!


To complete the Smoke Box Door I have to make some fake hinges, and a clip to hold it in place.  So, I cut the sheet metal to make the parts, and decided to bring it to width on the mill, like so:


I used a 1/32” thin parallel in the setup here, and since 22Ga sheetmetal is just a hair under 1/32”, the vice didn’t quite clamp on the steel.  So I used some pieces of double stick tape (where I never peeled off the backing on the other side) to add just a smidge of width to the part so it would stay in place, and it worked like a charm.


With the strips cut to width, I had to make a loop to connect to the fake hinge rod. I struggled with how to do this, but in the end used the vice, a hammer, and a nail (see it in the background there) to form the loops.  Probably not the best way, but it worked.


Then I drilled holes for the rivets:


Rounded the ends, and soldered them both to a 1” piece of brass as the fake hinge pin:


Next, I bent the piece for the snap clip:


And finally, I had to finish up the door itself.  The door had the basic shape, but I needed to drill the rivet holes and take a little sliver out of the bottom of the registration circle to allow room for a screw that will eventually be holding in the boiler.

So I get it setup on the mill and take out about 1/8” along the bottom of the registration portion:

Then I drilled all the rivet holes (I’d carefully marked the locations earlier).


And here is the happy Smoke Door family shot, before being assembled.

Some fun time with the rivet punches later, and here it is, fully assembeled:




Sadly, I made some ugly dings on the door with the anvil.  I’m not exactly sure what I’m doing to make that happen.  Maybe those are the times that the work piece isn’t exactly level?  I’m not sure.  I’ll be painting this part I believe, but I’d sure like to gain the skill of being able to rivet things without leaving those ugly marks


Regardless, here is the completed door, snapped into place:




And that’s it for the Smoke Door.

I found that little subassembly harder than it looked!  Well, maybe not hard, but just a lot of fidgety little steps that made it take a lot longer than I’d imagined!

Thanks for checking in,
Kim

[10KPete]

Beautiful!! Everything done very well. Pressure chucking is a valuable technique in the tool box and can allow all manner of jobs to be done easily. And as you found out, you don't need to leave any marks on the part.

I'm really excited about seeing this little beauty run!

Pete

[Steamer5]

Hi Kim,
 Nice progress, good recovery on the over size spigot! The end result looks the business!

As an idea to recenter the door, maybe gripping it between your aluminum spigot & the steel plug in the tail stock with just enough pinch to hold firmly, then using a nudger & apply light pressure to center it up, check with a dti repeat if required.

Cheers Kerrin

[Jo]

Nice save Kim, its so annoying when you take something down to find it is still oversized 

An alternative to hand filing would have been to use the four jaw independent to centre up the plate again to let you turn it down, being that it is a smoke box door you could get away with it being slightly off centre and no one would know  .

Jo

[vcutajar]

Beautiful work Kim and nice save.

Vince

[90LX_Notch]

Nice save Kim.   The wrap on the hinges really came out nice and the whole door looks great.

-Bob

[zeeprogrammer]

Good parts.
Good save.
Good progress.
Good fun.

Good going! 

[Kim]

Thank you all for the encouraging comments!

Those are some great ideas on ways to center up a piece like this, with literally nothing to hold on to! This is one of the great things about our forum; you can learn so many new, good ways to do things!  Not only how to do it right, but how to RECOVER when I screw up   And how to do things safely.  (I also really appreciate THAT!).

Thanks you for the help and encouragement!
Kim

[Don1966]

Nice work Kim all looks great......


Don

[scc]

Excellent as usual Kim                      Terry