Lack of knowledge Swarf Maker Needs help with a Steam engine

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Well-Known Member
HMEM Supporting Member
Feb 6, 2018
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Central Florida USA
First I wish to say Hello to Everyone on here and say thanks to all that have posted on this site. I have learned a lot by just reading other people post.
Second I hope I am not getting anyone upset or mad. I post this question under General Engine Discussion and had no reply, good or bad. So If I am posting in the wrong place or just being redundant please forgive and let me know so I do not keep making the same mistakes.

I need some help with a steam engine I built from bar stock. Most of you on here most likely know about this engine. It is called the River Queen Open Column Launch Engine by edelstaal.
This is the second time I am trying to build this engine. The first time I tried to machine this engine I was 14 years old. I crash and burn on that try (Broke more taps and drill bits then I made parts). Well this time around, I complete every part and not one broken tap or drill bit, (I am a lot older than 14 now) but I can not under stand how to layout the rotary valve. I have tried three times making this valve. I tried cutting the groves at 180 deg apart, 90 deg apart and also this last attempt I found another person on this site who is also a newbie. He was building the LMS model steam launch engine and having a little trouble with it. He cut the first grove starting at 34 deg to 235 deg then the second at 129 deg to 324 deg. I also tried the same on my last valve, and still no luck. I can not get this engine to run. Does any one have a better drawing or layout for this valve then the one that came with the River Queen kit. I would love to get this engine running.

Just a last minute thought. Does it matter if you start the inlet grove at 34deg to 235deg then the exhaust at 129deg to 324deg. What would happen if you change it around. Would this mater?
I cut the grove with a 1/16" dia. end mill bit on a rotary table.

If I post this in the wrong place please forgive and let me know under what title I should post it on this site.

Thanks in advance for any help.

Here is some photos of the engine. As you can see I made some changes, the valve is going to the front block next to the fly wheel, both blocks are made from cold roll steel (1018). I made a brass bushing to go into the back pillar block by the cylinder.
I've never built this engine, and I'm not familiar with it at all, but I had a look at the plans (which are fairly vague), and came up with this:

Valve timing.png
The valve can be orientated in any position on the crank with the set screw, so all that matters is how far around the valve to cut, and the orientation of the ports relative to each other.
So to cut the valve on a rotary table:
-Start at 0 degrees for inlet.
-Cut round to 215 degrees (that is 360-145 degrees from drawing, CAD program won't dimension above 180)
-Turn back to 55 degrees and move to exhaust.
-Cut round to 270 Degrees.
The drawing shows the orientation of the valve on the crankshaft with the piston at the top of it's stroke - how to set timing is covered in the description with the plans (page 9).

You've swapped the valve block, have you also swapped the inlet/exhaust grooves on the valve? Looks like you'd need to, or swap the exhaust and inlet on the block.

The only other thing to be careful of is the fit of the valve in the bore. Both the valve and bore should have a very fine finish and a very close sliding fit. There is only 1/16" gap between port grooves on the valve, which makes it difficult to get a good seal.

Hope that helps. As I said I've not built the engine and I'm no expert, so bear that in mind. I could be wrong!

Thank you for all of the reply's but do to health reasons. I am not able to proceed at this time, But as soon as I get back on my feet and into my shop I would love to give it a go with all of the suggestions posted. Thanks again I will keep all updated if and when I get back on feet and get this engine to run.

"Never give up. Never surrender", which is the mantra from Galaxy Quest.

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