Ignore this topic

[NickG]

I agree with John also, why does the engine need 35 psi to run? That is an incredible amount for a small engine and suggests that if something is slightly out, it won't run at all. Can I ask what was built as the first team build?

I think for this one it would still need to be something with a proven track record, something that we know is going to work, even if there are some small errors. I would suggest something like a simple slide or piston valve steam engine or are the members of the build wanting something more challenging this time?

Nick

 

[NickG]

I think Jan ridders pressure controlled two stroke might be the best bet for a first i.c. engine. The only thing requiring a cam & timing is for the ignition.

By the time you are on to this, I may have had a crack at this engine myself and would know some of the ins and outs of it.

Nick

 

[Brass_Machine]

Gail,

That video is rather neat. I like the action of that engine.

Posting youtube videos is easy. In the url for the video, copy everything after the "=". In your case, it is f_KaGygrND0 that you are copying.

http://www.youtube.com/watch?v=f_KaGygrND0

Click the youtube button. It is in the row right above the smilies, second from the left. When you do that, you will get the folling code:

[youtube=425,350][/youtube]

At that point, paste what you copied in:

f_KaGygrND0

Then you are done ;D

Eric

 

[kvom]

I guess I will volunteer for something really easy, esp. if the build period is pretty long. I will ask the instructor if I could use one of the school lathes out of school, or even as a learning project in the class.

I also have a friend with a 12" Sheldon and lots of tooling, plus a Bridgeport, and I'm sure I could use his gear if needbe.

 

[kvom]

Sign me up for a dead simple part

 

[GailInNM]

Eric,
Thanks for the video assistance, and for cleaning up my post for me. Maybe next time I can do it on my own.

It's hard to believe that I have become such an appliance operator of computers. In the early 70's I designed and built a PC before there were any around. An 8008 based machine with a clock rate of 350 kiloHertz. Then wrote an assembler for it which the was used to write a Basic compiler of sorts called GOSUB. That stood for Gail' Own Screwed Up Basic. Things have progressed from there, but I still dislike Windows so much that I avoid learning any more about it than necessary. The computer I use for most of my design work is a purpose built machine running DOS 6 in native mode with a 2.3 GHz AMD chip running Autocad 12. You would not believe the performance as compared to running Windows based ACAD 14 and 2000 on my Windows based machine. Any how, wrong thread for this kind of nonsense.

Glad you enjoyed the video. I will do more now that I know how. Thanks again.
Gail in NM

 

[Brass_Machine]

I was talking to Powderkeg today... He has the bronze to donate to the flywheel cause if we decide to double up the engine. I am sure that either myself or Zeuzrekning can do the drawing and model it in 3D for us.

So double it up and make it a larger piece?

Eric

 

[Powder keg]

Glad you decided to jon us Kvom! I think you'll do fine. If you have any problems just ask)

Wes

 

[zeusrekning]

Double it. If we run in to any issues drawing it up I'm sure we can get help from the guys here.
Tim

 

[CrewCab]

I'm watching this thread with interest gang and really looking forward to seeing what you go for,

Just a thought from a newbie, "doubling up" ......... are you likely to run into some issues with bolt sizes and clearances etc , do 3mm bolts really need to be 6mm ............. and ..........

...... for instance, if you double up a a 1/2" bore cylinder with a 1/8" wall do you need a 1" bore cylinder with a 1/4" wall ....... I would have thought the wall thickness would only need to increase a little ???

just a couple of thoughts, please feel free to ignore me if this is a load of crap


anyway, main point, can you take care of this at the drawing stage or would "doubling up" be better going to a design team first, then built a bit later, once any snags are ironed out.

CC

 

[Brass_Machine]

Engine for this team build will be the coombers. After we finish this one, we will do a longer build over fall/winter for an IC.

Now... do we double it up?

Eric

 

[Powder keg]

Remember, I'm donating the bronze for those 4" flywheels) I might even have some aluminum plate for the cam ring) I put in my vote...... Make her big!!!! Even though it's still won't be that big of an engine, with a 3/4" bore.

Later, Wes

 

[zeusrekning]

anyway, main point, can you take care of this at the drawing stage or would "doubling up" be better going to a design team first, then built a bit later, once any snags are ironed out.

CC

This is what I would like to do. Have it scaled up and make fresh , mabey even toleranced , drawings. That may be a little wishful but I would not want or expect everyone to try and scale up the parts individually.
Tim

 

[Powder keg]

Of coarse, Tim. They need to be re dimensioned and sent to everyone to be redlined and have all the foreseeable trouble spots fixed. I think we need to incorporate adjustable rollers into the design also. This is such a simple engine that I don't see many problems.

Wes

 

[zeusrekning]

Of coarse, Tim. They need to be re dimensioned and sent to everyone to be redlined and have all the foreseeable trouble spots fixed. I think we need to incorporate adjustable rollers into the design also. This is such a simple engine that I don't see many problems.

Wes

Keeping in mind there are so many newbies in the build including me with steam, it may be nice to have some input from other members of the board. But I just remember Gail has built one of these before
so that will be a big help.
Tim

 

[bretk]

If we double it up it gives us a lot more possibilities for adjustment and fine tuning, like adjustable rollers as opposed to having wedge them and solder them in place during final fit up. It seems like a much more elegant solution. Looking at the photos of how the first team build is coming, this engine would be a real showpiece at 2x scale! ;D

-Bret

 

[GailInNM]

OK, time to see if I can irritate Eric again. I tried a couple of times, but he is too good natured. The votes seem to be split about half and half with the majority abstaining.

How about we build a Big Coomers AND a Small Coomers. The Coomers as shown by Elmer only has a a dozen different parts if built to print and 16 the way I built it. Most of them are simple and would easily fit on the smaller machines. It could be a shorter term project primarily for a small group of beginners with none to a few engines under their belt. Of course more experienced builders would be welcome to join in if they wanted.

None of the parts require CNC. The cam ring can be made quicker on CNC, but I have a much easier way than Elmers to make it on a manual machine if someone wanted to. There are only a few changes that I would like to see made to the design, and mostly they are to make machining easier. Even if no changes are made, the engine will run fine.

I would be glad to head up the Small Coomers group, under Eric's guidance and supervision of course, if it were desired. Of course there would be no reason that people could not participate in both groups if they wanted. My guess is that the Small Coomers group would be finished before much metal was cut on the Large Coomers. I would probably like to participate in both groups, but mostly I don't want to see any beginners left out.

Let me know what you think. Of course Eric has veto power if he does not want to see the group split, and that is as it should be. After all, the team build all started with him and we should thank him for doing so.

Gail in NM, USA

 

[te_gui]

I'm in for doubling as well, seem like there would still be smaller pieces with the glands and things that folks with smaller equipment could contribute. I haven't really sat down and studied the plans with an eye for scaling but looks fairly straight forward

Brian

 

[Powder keg]

Yesterday I started polishing. These take some time to do. That form tool was top quality. I honed the edge with a stone so it would leave as few tool marks as possible. But it still left some. Mainly on the concave portion. To prepare it for polishing I had to first emery the marks out. Then I hit it with some scotchbrite. The stuff you clean your pots and pans with. Then I used some Mothers polish on a disposable shop rag. This made a mirror finish on these little parts) I'll post some pictures later)

Wes

 

[Powder keg]

Those are great!!! I'm excieted about this engine! i think it will be the nicest one that i have. That wood looks nice also.

Thanks, Wes