Open Column Launch Engine from Kit

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
bearcar1 said:
And don't forget to get a present for Foozer's wife's B'day!! Rof} Rof} Rof}

Funny Funny

She gives me one for dinner and the other for tonight's hopeful, not sure of the order :)

B-Day.jpg
 
Carl,
Very nice engine, very useful lessons for the beginners in building small engines. :bow:
I bet many of us who started before the net wished we had had such a great support group.
So you are going to make some special present for your wife now?
Dave
 
More re hose barbs etc....

I fly (which means I spend a fair amount of time crashing and repairing) radio controlled helicopters and aircraft, we use silicon fuel tubing and "pressure nipples" which I think may fit the job for model engines.

For example, if you follow this link http://www3.towerhobbies.com/cgi-bin/wti0095p?FVPROFIL=&FVSEARCH=pressure+nipple you will see what I mean. Not sure what the thread is on the pressure nipple, but should not be too much of a problem to sort?

If you enter "fuel tubing" in the search box on the top right of the page you will get loads of choices of colours etc. As this fuel carries the exhaust gases from the muffler/silencer on IC engines to the fuel tank, I think it should withstand steam as well as air.

No idea if this helps, and I have never used TowerHobbies before, being in the UK - I simply used their site as an example.

Regards, A
 
bearcar1 said:
And don't forget to get a present for Foozer's wife's B'day!! Rof} Rof} Rof}

He's on his own. I need to worry about my own wife's birthday. :big:
 
DavesWimshurst said:
Very nice engine, very useful lessons for the beginners in building small engines.
I bet many of us who started before the net wished we had had such a great support group.

Thanks Dave. Yeah...this forum has been invaluable and will continue to be so.

DavesWimshurst said:
So you are going to make some special present for your wife now?

I thought I did! You said it was a nice engine. And it's special...in it's way.
 
Alasdair: Thanks.

I had actually gone to a hobby shop nearby to look for fittings but didn't find anything. I wonder though if the higher pressure of steam (air in this case) would be a problem? I think I was running at 80 or so PSI - at least initially, to get the engine to run in.
 
As it happens I was in the hobby store today and looked at some of the 'pressure fittings'. I couldn't figure out what the pressure was all about since they were drilled straight through (I was hoping for some sort of check-valve), but they came in several numbered threads-- #10-32 & such. They were in the airplane parts section, so go for a store that caters to the airplane builders.

It would be pretty easy for a handy fellow with a lathe and an appropriate threading die to crank one out too ;)



 
shred said:
It would be pretty easy for a handy fellow with a lathe and an appropriate threading die to crank one out too ;)

Hee hee hee. Handy. Yes. Appropriate threading die. Hee hee hee.

I will be revisiting this whole topic when I get round to mounting my engines onto wooden display bases and providing piping and fittings so I can easily hook them up to air (or even steam in the future!) and run them.

Never wanting for a topic!
 
Still doing some analysis and collecting lessons learned...

I mentioned earlier that I drilled/reamed the cylinder first and then turned/sanded the piston to fit. What I may not have been clear about is that I think the cylinder bore had a slight taper to it. It would fit onto the piston (while piston was in the lathe) better on one end than the other.

I also mentioned that it was after this operation that the holes in the cylinder were drilled and tapped for the columns. And, that I wondered if this causes metal (brass) to push/bulge into the cylinder's bore. This happened to be the end of the cylinder that didn't fit the piston as well.

Perhaps the holes were made a little too close to the bore?

If this is true, then there would be 4 bulges into the cylinder. If you image a circle drawn to touch the peak of each bulge then there would be 4 gaps between the drawn circle and the cylinder wall. Since it was the piston I was modifying...the gaps would remain allowing a lot of leakage. It would then require more pressure to move the piston.

Comments?

Would a telescoping gauge help me?
 
Carl,
If there are bulges in the cylinder walls they may show up as shiny spots as the engine gets some more running time on it. Telescoping gauges take practice to get accurate results. So sure get a set and practice using them. Others may have advice on brands, mine are Mitutoyo bought decades ago and work ok.

Dave
 
DavesWimshurst said:
If there are bulges in the cylinder walls they may show up as shiny spots as the engine gets some more running time on it. Telescoping gauges take practice to ...

Thanks Dave. Very good tip. When I take it apart I'll check. It's at work right now drawing some interest. :) Mainly that they can't believe a software guy did it. The mechies are worried. :big:

Have cheap telescoping gauges. Will practice. Marv and others gave some good tips on technique.

Thanks again.
 

Latest posts

Back
Top