Cox Engines Forum
You are not logged in! Please login or register.

Logged in members see NO ADVERTISEMENTS!


Here. Hold my beer. - Page 2 Cox_ba12





Log in

I forgot my password

Search
 
 

Display results as :
 


Rechercher Advanced Search

Latest topics
» Another one ready for the Weekend
by 944_Jim Yesterday at 10:55 pm

» The scrap yard Piper Cub aka Silver Lining/AIRTRUK
by andrew Yesterday at 8:28 pm

» My New Build Attempt
by Yabby Yesterday at 7:23 pm

» Guillows Cessna 150 build circa 1970 (Build Log)
by 944_Jim Yesterday at 4:42 pm

» Another Cox .010 converted to R/C & P-51 Mustang.
by balogh Yesterday at 3:51 pm

» .020 PeeWee
by rdw777 Yesterday at 3:22 pm

» pictures of my engine collection.
by cmulder Yesterday at 12:49 pm

» Scientific King Cobra
by rsv1cox Yesterday at 8:02 am

» .010 Tee Dee ever so nasty in a blister pack
by Marleysky Yesterday at 8:01 am

» The Ubiquitous Yamaha TZ Grand Prix Racing Bike
by Yabby Yesterday at 12:29 am

» There are more and more new  cool engine models
by rmjtools Tue Sep 27, 2022 12:35 pm

» Cox car (Riviera and others) fan/flywheel/drive gear
by pertti_jarla Tue Sep 27, 2022 11:04 am

Cox Engine of The Month
September-2022
fredvon4's

Hot Tee Dee .049 featuring a Turbo Head and exhaust collector



PAST WINNERS
CEF Traveling Engine

Win This Engine!
Gallery


Here. Hold my beer. - Page 2 Empty

Here. Hold my beer.

Page 2 of 2 Previous  1, 2

Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  roddie Wed Oct 21, 2020 7:28 pm

gkamysz wrote:Haha that's great! It just needs a substantial spring somewhere to keep that cylinder in check.

Yes.. and BTW.. awesome thread Mark. Is there the possibility to fit an OEM exhaust-shield between the cases? I lost my pics.. but it's a stamped-steel part shaped the same as a case gasket.. and having a protrusion designed to deflect hot exhaust gases. Maybe it would provide a friction/detente for your faux cylinder/needle.

Why does the rear glowhead loosen-up? Maybe another gasket or two would help?
roddie
roddie
Top Poster
Top Poster

Posts : 7447
Join date : 2013-07-17
Age : 62
Location : N. Smithfield, Rhode Island

http://www.stilburnin.com

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  roddie Wed Oct 21, 2020 8:39 pm

Here's an image of the Bee engine's exhaust-deflector.

Here. Hold my beer. - Page 2 Exhaus13

or..

Here. Hold my beer. - Page 2 Exhaus14

A short piece of wooden-dowel in-between with a flat/notch filed might stay in place.. at a minimal weight penalty. Basically a friction-collar.
roddie
roddie
Top Poster
Top Poster

Posts : 7447
Join date : 2013-07-17
Age : 62
Location : N. Smithfield, Rhode Island

http://www.stilburnin.com

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  batjac Wed Oct 21, 2020 10:50 pm

Great idea, Roddie! Not between the cases, but between the Goldberg mount and the rear case. That should work. Let me think on it for a while. Maybe a thin sheet of cork or rubber to rub against the cylinder. I should have some cork sheet stashed away somewhere for either clarinet repair, or Mosin bedding.

The Craftsman Mark
batjac
batjac
Diamond Member
Diamond Member

2020 Supporter

2022 Supporter

Posts : 2118
Join date : 2013-05-22
Age : 59
Location : Broken Arrow, OK, USA

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  batjac Fri Oct 23, 2020 2:15 am

Continued:

With the back case in place I screwed in the needle valve to see where the fuel nipple is.  I then marked the position and drilled a hole in the bottom of the rear case.  

Here. Hold my beer. - Page 2 DSCN7469
Here. Hold my beer. - Page 2 DSCN7475


Then I put the two cases back together.  

Here. Hold my beer. - Page 2 DSCN7477
Here. Hold my beer. - Page 2 DSCN7488
Here. Hold my beer. - Page 2 DSCN7493
Here. Hold my beer. - Page 2 DSCN7498


For reference, I measured the weight of this engine against an 8cc tanked Bee.  This engine is only 0.45 ounces more than the tanked engine.  2.35 ounces vs. 1.9 ounces for the Bee (68 vs. 54 grams).  

Here. Hold my beer. - Page 2 DSCN7514
Here. Hold my beer. - Page 2 DSCN7517
Here. Hold my beer. - Page 2 DSCN7521
Here. Hold my beer. - Page 2 DSCN7526


For the faux plug I dug around the old engines box looking for a bad glow head and found an engine with a glow head missing the filament.

Here. Hold my beer. - Page 2 DSCN7534


Everyone wanted to know how I was using the cylinder to needle the engine.  The obvious method I was going to use was with a piece of fuel tubing to rotate the needle valve.  I didn’t want to ruin the existing needle on the reed valve assembly. So I dug around and found a spare fine needle.  I cut the top off of this and then slipped a short length of small fuel tubing over the stub.  As I said, I didn’t like my first idea.  So I just did a quicky change to try out my new idea.  All I did was cut a shim from a cookie tin for the fuel tubing to go through.  The fuel tubing sticks out of the top and when I put the faux plug on, it compresses the fuel tubing and traps it.  Thus, when I rotate the cylinder, it rotates the shim and the small fuel tubing attached to the needle.  I started off by opening the needle valve three turns, then installed the cylinder in the case backed out ¾ turn from all the way in.  Then I tightened the faux head down.  Unfortunately, I had a little too much fuel tubing sticking above the shim, so the head didn’t tighten down as I’d hoped on the test I did the other day.

Here. Hold my beer. - Page 2 DSCN7555


Now that I know the idea works, I pulled the tin shim and made a new insert from brass shim stock.  I took a glow head gasket and put a tape backing on it.  I trimmed the tape around the outside of the gasket and taped it to the shim.  Next I used a Sharpie to mark the outline.  After that I drilled out the center for the fuel tubing and then trimmed the insert to the same size as a glow head gasket.  I put the insert in place and pulled the tubing through the hole.  Installing the faux head seemed to do much better with this brass shim and it tightened down much better than the tin shim did.

Here. Hold my beer. - Page 2 DSCN7558
Here. Hold my beer. - Page 2 DSCN7568
Here. Hold my beer. - Page 2 DSCN7571
Here. Hold my beer. - Page 2 DSCN7577


Lastly, I went ahead and dug out a cylinder heat shield and installed it between the rear case and the Goldberg mount.  I have to admit that Roddie’s idea to use the heat shield to provide friction resistance to the cylinder was be…  ***ahem***  Was bet…  ***cough***  Was bett…  ****wheeze***  Was bette… ***hack, cough***  Was equally as good as my idea, and I went with his instead.

Here. Hold my beer. - Page 2 DSCN7583


The Congested Mark
batjac
batjac
Diamond Member
Diamond Member

2020 Supporter

2022 Supporter

Posts : 2118
Join date : 2013-05-22
Age : 59
Location : Broken Arrow, OK, USA

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  rsv1cox Fri Oct 23, 2020 7:25 am

roddie, Mark; roddie, Mark; roddie, Mark. Two heads are better than one especially on model engines.

Good one Mark!

Bob
rsv1cox
rsv1cox
Top Poster
Top Poster

2020 Supporter

2021 Supporter

2022 Supporter

Posts : 8313
Join date : 2014-08-18
Location : West Virginia

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  getback Fri Oct 23, 2020 8:07 am

Way to improvise Mark and another Good helping idea from roddie !! Have you ran it since the upgrade ? The weight came in good . Babe Bee .049 Small Cox Logo
getback
getback
Top Poster
Top Poster

2020 Supporter

2022 Supporter

Posts : 8986
Join date : 2013-01-18
Age : 65
Location : julian , NC

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  KariFS Fri Oct 23, 2020 9:43 am

I think this is the most elegant ”faux twin” that I have seen. Would look really good on a sport scale biplane or a model of one of those old small aircraft that had an inline twin.

Now that the ”rear face” of the engine block is flat, it would be possible to make a radial mounting plate using maybe 1/8” aluminium. Countersink the screws on the back, and drill mounting holes maybe in a tanked bee or horseshoe pattern. Would make it a little bit more robust, considering the extra weight and moment compared to a standard 290 engine, and the possible brittleness of the Goldberg mount Two Cents

Anyway, just wanted to let you know that I am quite impressed by the ingenuity involved, and even though there were not many greenies, I am sure I am not the only one Thumbs Up
KariFS
KariFS
Diamond Member
Diamond Member

Posts : 1927
Join date : 2014-10-10
Age : 50

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  Oldenginerod Fri Oct 23, 2020 8:09 pm

Just a reminder of the "original concept" picture I posted which prompted Mark's build.  
Here. Hold my beer. - Page 2 Screen23

I also found another.  This time we can try to figure out the tank/intake arrangement.  Interesting to note it has the exhaust shield on the rear cyulinder as Roddie suggested.

Here. Hold my beer. - Page 2 Screen24
Oldenginerod
Oldenginerod
Top Poster
Top Poster

Posts : 3695
Join date : 2012-06-15
Age : 59
Location : Drouin, Victoria

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  batjac Sat Sep 03, 2022 9:11 pm

Okay.  I finally got around to building a plane for this.  No name for the plane yet.  But I also wanted to try making a flapped sheet wing plane, so this is two first flights in one.  The balloon tank is a 9” party balloon.  It’s filled up about half full.  That got a 9 minute and 45 second run.  On the way home I stopped at WalMart and got a bag of 7” balloons, and that’s only because they didn’t have 5” party balloons…  Ah, well.  They’re only 99 cents for the bag of 30 balloons.  I can always use the 9” balloons for the Medallion .15 on my SIG Acromaster.







The Double Mint Mark
batjac
batjac
Diamond Member
Diamond Member

2020 Supporter

2022 Supporter

Posts : 2118
Join date : 2013-05-22
Age : 59
Location : Broken Arrow, OK, USA

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  davidll1984 Sun Sep 04, 2022 7:37 am

[quote="Oldenginerod"]Just a reminder

I also found another.  This time we can try to figure out the tank/intake arrangement.  Interesting to note it has the exhaust shield on the rear cyulinder as Roddie suggested   Here. Hold my beer. - Page 2 Scree155


Huh... look like the cars engine is made functional I don't know but maybe look at the piston inside look the same like if this one was runing also Huh... custom made crankchaft adaptor?? And if the motor really works it must have a lot of torque Eyebrows Thumbs Up Maybe that would be one of my future projects. I could use a leaking crankcase to modify in the rear I have already thought about how to couple two motors but certain technical difficulties are present.
davidll1984
davidll1984
Diamond Member
Diamond Member

Posts : 2038
Join date : 2020-02-12
Age : 37
Location : shawinigan

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  andrew Sun Sep 04, 2022 9:28 am

batjac wrote:......That got a 9 minute and 45 second run......

The Double Mint Mark

That's about 5 minutes and 45 seconds too long for me.  You're a brave man!!

BTW, thoroughly enjoyed the video. The engine ran really well throughout - congrats.

a--
andrew
andrew
Diamond Member
Diamond Member

Posts : 1594
Join date : 2011-08-11
Age : 74
Location : Western Kentucky

http://web2.murraystate.edu/andy.batts/ps/POWERSUPPLY.HTM

Back to top Go down

Here. Hold my beer. - Page 2 Empty Re: Here. Hold my beer.

Post  Sponsored content


Sponsored content


Back to top Go down

Page 2 of 2 Previous  1, 2

Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum