Chris's Diesbar Engine Build

[Sanjay F]

Here's a video I made at the Berlin Technology Museum 10 years ago.  This paddle engine is a compound, but it seems to have a lot in common with the Diesbar.

I saw that engine at the museum earlier in the year, it was my favourite in the collection 

[Sanjay F]

The paddlewheel parts that I had laser cut by FabWorks.com just arrived - they look great! The edges were all deburred, everything is nice and smooth. Checked the holes that will be threaded, tap goes right in so I don't need to redrill them. Accuracy looks quite good.
Here is a picture of the parts: two outer rims, 20 spokes/paddle-holders, and 10 links for the feathering mechanism. I've already started on the hubs (see previous post) and will make up the two sets of struts that act like bicycle spokes and hold the two sides in alignment, and will re-use the paddles from the printed version. Yes, there are a couple size holes in the parts - some are for screws, some are pivot points.

First step will be to make up a bending guide from a wood block - the spokes get curved slightly along the long straight section, and a tighter bend out near where they flare out and curve, so the three holes in a row are vertical where they cross the rim. Um, thats the second step, I need to tap the holes out at the end of the spokes first. The bends are shallow so no issues with cracking. With all the spokes tapped and bent, I can start running in the screws to hold them together, and measure for the hole spacing from the center of the hubs and get the hubs drilled/tapped to attach the spokes. Once that is assembled, I'll measure for the other struts I need to make, they are simple round rods with flanges attached on the ends. Ought to have the wheel together in a few days.

I'm trying to figure the diamter of rims?

[Michael S.]

I expect to be at the German Museum of Technology on September 19th. There is a special exhibition of model steam engines there as well. I absolutely have to see that compound steam engine.

[crueby]

Here's a video I made at the Berlin Technology Museum 10 years ago.  This paddle engine is a compound, but it seems to have a lot in common with the Diesbar.

<a href="https://www.youtube.com/watch?v=WSRfnHVcVwY" target="_blank">http://www.youtube.com/watch?v=WSRfnHVcVwY</a>

Looks like its a later Penn engine? Has a Stephenson  reversing  linkage with two eccentrics rather than the earlier slip eccentric,  and as you say is a compund. The frame design is very similar.  Neat to see!

[crueby]

The paddlewheel parts that I had laser cut by FabWorks.com just arrived - they look great! The edges were all deburred, everything is nice and smooth. Checked the holes that will be threaded, tap goes right in so I don't need to redrill them. Accuracy looks quite good.
Here is a picture of the parts: two outer rims, 20 spokes/paddle-holders, and 10 links for the feathering mechanism. I've already started on the hubs (see previous post) and will make up the two sets of struts that act like bicycle spokes and hold the two sides in alignment, and will re-use the paddles from the printed version. Yes, there are a couple size holes in the parts - some are for screws, some are pivot points.

First step will be to make up a bending guide from a wood block - the spokes get curved slightly along the long straight section, and a tighter bend out near where they flare out and curve, so the three holes in a row are vertical where they cross the rim. Um, thats the second step, I need to tap the holes out at the end of the spokes first. The bends are shallow so no issues with cracking. With all the spokes tapped and bent, I can start running in the screws to hold them together, and measure for the hole spacing from the center of the hubs and get the hubs drilled/tapped to attach the spokes. Once that is assembled, I'll measure for the other struts I need to make, they are simple round rods with flanges attached on the ends. Ought to have the wheel together in a few days.

I'm trying to figure the diamter of rims?

The rims are just over 8" diameter. The spokes get bent in towards the hubs so the rims are farther outwards from the hubs. That should show in the earlier pictures of the  printed version.

[Sanjay F]

That's a fair size and looks like a bit of a puzzle to the outside observer with all the different holes everywhere! 

[crueby]

That's a fair size and looks like a bit of a puzzle to the outside observer with all the different holes everywhere! 

Its a bit of a puzzle with it on the table in front of me!

[crueby]

Slight diversion from the crankshaft by something shiny...      I decided to see how well the paddlewheel parts went together. I tapped the holes in the spokes and rim, got them assembled, then drilled/tapped the holes in the shop elves satellite TV dish hubs. Set up the rotary table on the tilting table to level out the spokes for drilling.

Two holes per spoke

After tapping those holes, the first side was assembled. Finicky to get things started, but not bad.

and then the second side. The sides are just slid onto a piece of round bar for now, not attached to each other.

and end view to show the dish to the spokes,

Next up will be to make the crossbars and struts, marked with blue arrows in this picture of the 3D printed wheel:

The metal version is much stronger even without the braces, as expected. Coming together well!

[Sanjay F]

They look great, so much better 

SUGGESTION: make a ferris wheel out the the old set, obvioulsy. steam operated! 

[Michael S.]

Beautiful!   

[crueby]

They look great, so much better 

SUGGESTION: make a ferris wheel out the the old set, obvioulsy. steam operated! 

Interesting idea!

[crueby]

Beautiful!   

Thanks Michael!

[Kim]

That is really neat, Chris!  The Ferris wheel Paddle wheel is really coming together! 

Kim

[cnr6400]

  That's taking shape Chris! The metal wheel's looking great.
I was confused earlier this week when one of my shop gnomes was on the phone with "someone" asking about what channels on elfsat TV are available and how to aim a brass dish....sounded like a pain in the azimuth...

[crueby]

That's taking shape Chris! The metal wheel's looking great.
I was confused earlier this week when one of my shop gnomes was on the phone with "someone" asking about what channels on elfsat TV are available and how to aim a brass dish....sounded like a pain in the azimuth...

   Yup, he was on the phone to one of my guys. I kicked him in the azimuth...   
Laid out some small square bar to make the ends of the crossbars with, will thread the ends of some round bar as the middle rod. Have not decided how to make the angled stays yet. Several options, the one I'm leaning towards is to make them from narrow flat tool steel, drill the ends, and bend the ends to the angle needed. That plan may change!  I'll do them after the crossbars are in so I can get an accurate actual measurement of the length needed for the angled stays, the angled ones will add a lot to the appearance of a web.

Also worked out finally how I will make the holders/stops for the eccentrics. On the real ship, the crankshaft has some stop blocks attached that both keep the eccentric from sliding sideways, and also set limits on how far they can slip for reversing. For the model, I want those positions adjustable so I can fine tune the timing of the eccentrics. I've come up with a way to make it as a bronze bearing surface for the eccentric itself, with a circular track, like a T track, next to it for two stop blocks that can be adjusted. More pics on that as it comes together. We've got another pond run this weekend, so may not get as much shop time in as normal.