Hi Everyone,
I did some work last weekend, but never got a chance to upload the pics. So I’ll combine last week’s update with this week’s update to make one SUPER update! Although, looking at it you’ll realize that in two weekends, I accomplish half of what most of you do in any given single session. Ah well, it is what it is!
Last week, I started on the Cylinder. One part! How hard can it be, right? Well, I’m finding it a LOT of work!
The cylinder is specified to be bronze, so for this project I ordered some 1” bronze rod. Nice stuff to machine!
I used the 3 Jaw chuck here for several reasons. First, my 1” 5C collet does not allow 1” stock to feed through. There are internal threads at the back of the collet that make it so you can’t pass 1” stock through. This has caught me several times. However, there’s another reason – the Bronze rod comes significantly larger than the specified size – several ten’s of thousandths. So it won’t even FIT in the 1” 5C collet!
You can see that issue pretty clearly here: this is after I've turned the bronze down to 1” and you can see a pretty substantial shoulder there!
After bring it down to 1”, I drilled a hole of about 3/8”.
And bored it out to just under 1/2".
Then reamed it to 1/2”.
And cut it off slightly over sized.
Then flipping it around in the chuck, I faced it off to the specified width of 1 1/16”.
To make the face for the steam chest, I cut a small slab out of the round bronze stock, like so:
And removed the slab from the parent stock using the horizontal band saw.
With the small slab free, I squared it up on the mill, and shaved it down to size on all six sides.
And this was where I ended last Saturday! Two nice pieces of bronze, destined to be one!
On Sunday, I calculated how much of the cylinder needed to be shaved away to make the steam chest base fit and then whittled it off.
To keep the little rectangle of bronze in place during soldering, I decided to put some brass pins in. I used a bunch of small clamps and scrap packing material to hold the two parts together for drilling:
I was using 3/32” rod, and chose to use a 3/32” drill. I knew this would make a slightly oversized hole, but I needed the bronze piece to be able to drop down in place using gravity. If the hole was too tight of a fit, it wouldn’t drop when the solder melted.
My test fit looked pretty good to me – just a little loose.
Here’s all the pieces ready for soldering.
Now cleaned, fluxed and with several bits of hard solder in place between the joint. I also set the part up on some fire bricks in a way that allowed me to get to all sides of the part so I could heat it not just from the top and sides, but from inside the bore too.
And here we are, post soldering. It went just as I hoped it would! As the parts started to turn a gentle, deep red, the bronze rectangle just ‘dropped’ into place – first on one side, then on the other. You can see where I kept the flame in one place too long and melted one of the 3/32” pins. But that part will be removed, and the rest of it turned out unscathed!
After some pickling and cleanup, I put it in the mill to remove the brass pins. Then I took a very light skim across the steam chest area to guarantee that it was completely flat.
Now we have the basic cylinder shape! One thing I got out of order – I should have done the soldering BEFORE I reamed the 1/2” bore. The soldering really left a nasty ripply crust on everything inside.
I tried using the 1/2" reamer on the boar again, but it didn’t do anything. I’m going to have to hone it out some. Luckily, the 1/2" bronze I got for the piston is also oversized (like by 40+ thousandths). So I’ll do a little honing and make the piston to fit.
Thus ended last Sunday.
Now, we’re up to today!
During the week I’d ordered a 1/2" Flex Hone from Amazon. $10 and it was shipped to my door the next day (it was supposed to be 2 day shipping, but it only took a day!). I used this Flex Hone to clean up the inside of the cylinder.
I actually held the hone by hand – well, I held the drill check by hand
That little wire handle looked like it would be hard to hold, and like it could really hurt if it got away from me! The Flex hone worked very well. I followed the instructions on the back of the package and it just worked.
The bore is now 0.503”, which isn’t going to be a problem in the slightest
And more importantly, I was able to keep it consistent all the way through the bore (or at least, consistent within the tolerances that I can measure it to; +/- 1/2 Thousandths.)
After working through that issue, I worked on the steam passages. Using math and the DRO, I drilled 0.055” holes in line for the steam ports, and 7/64” holes for the exhaust port.
Then I opened up the exhaust port with a 1/8” 2 flute end mill:
And did the same for the steam ports using 1/16" mill:
And as my final step of the day, I drilled and tapped the holes to hold the steam chest in place.
That brings me to the end of my shop session today! Sorry for how long this was. But even with the length, I didn’t get that far. I still have to drill the rest of the steam passages and the holes for the cylinder drains.
Thanks for checking in!
Kim
