Sep 23, 2011, 06:37 AM
Good Better Best quest.
olmod's Avatar
Quote:
Originally Posted by Twin-Stack View Post
Gluehand, I think a replacement for the Frog "clack valve" would have to be made from spring steel, as the original is quite rigid. This means that the whole valve is free to move forward under the negative pressure from the crankcase when the piston is rising. The reed valve (usually made from beryllium copper or similar) tends to be quite flexible, and even though retained by a circlip, can "bulge" in the middle to allow fuel mix to enter. BOB
Also known as the vibramatic one of the first new motors I ever owned ,most were 2nd hand and although I had mine apart from time to time I'm sure the edges weren't knife edged.
Sign up now
to remove ads between posts
Sep 23, 2011, 07:33 PM
Closed Account
Quote:
Originally Posted by olmod View Post
Also known as the vibramatic one of the first new motors I ever owned ,most were 2nd hand and although I had mine apart from time to time I'm sure the edges weren't knife edged.
Here's a couple of photo's of the animal in the flesh. It says in the Engine Test of the 149 that the disc is shim steel, 0.005 in. thick. I think that, on examining it more closely, only one (the seal) side is ground. By holding a straight edge across the disc, I can see daylight on either side. BOB
Sep 23, 2011, 07:57 PM
Registered User
Gluehand's Avatar
Quote:
Originally Posted by Twin-Stack View Post
the disc is shim steel, 0.005 in. thick.
Maybe something like an 'old school' razor blade.... (thinking of potential 'raw materials' for making a disc..)

Sep 23, 2011, 10:06 PM
Registered User
earlwb's Avatar
I can see a couple of ways to go about making it.
One way is to get some sheet metal around that thickness, maybe a little more thick. Then cut out several pieces. Then using two more thick washers or pieces, you could clamp them like a sandwich together tightly. Then using a milling machine and a rotary table, you machine the circle size to shape. The thin pieces in the middle ought to come out pretty good and useable with little or no lip or edge on them.

One could also chuck up a piece of steel round stock in a lathe and carve a piece or two out of it.
Sep 23, 2011, 10:36 PM
Good Better Best quest.
olmod's Avatar
shim steel rough cut to oversize sandwiched between a sacrificial round bar and another between the tailstock centre on a lathe should do it, perhaps after cutting using a grinding head or emery taped to finish the edges while still chucked.
Sep 24, 2011, 05:39 AM
Registered User
fiery's Avatar

KO diesels


I have one ... it came from the estate of a flying colleague, it's an .099 with a tall vertical intake stack, like the old PAW 1.49 cc and 2.59 cc's.

It has a backplate held on by three machine screws. Will post a pic if anyone is interested. It's compression is gone to "compression heaven", but I plan on having a new piston made for it. Would love to run it.

I know nothing of KO engines. Does anyone know anything about them?
Sep 24, 2011, 08:12 PM
Closed Account
Quote:
Originally Posted by fiery View Post
I have one ... it came from the estate of a flying colleague, it's an .099 with a tall vertical intake stack, like the old PAW 1.49 cc and 2.59 cc's.

It has a backplate held on by three machine screws. Will post a pic if anyone is interested. It's compression is gone to "compression heaven", but I plan on having a new piston made for it. Would love to run it.

I know nothing of KO engines. Does anyone know anything about them?
Fiery, lets see it then. Didn't Adrian Duncan do an article on KO's ? If not, about all I know is that they were made by the Kondo brothers,who I think were speed flyers in Japan. If you go to the Vintage Glow Engines thread and look for the Global Engine Reviews (starting on page 23) you will find a few mentions of KO engines. BOB
Sep 24, 2011, 08:44 PM
Registered User
fiery's Avatar

Ko .099 Diesel


Here 'tis. It looks sad, anodising long faded from head, but is cosmetically only a little marked, apart from prop driver (sigh, has the ever unappealing plier scars) and one oblongated mounting hole. Also missing screws from backplate and the comp screw is in another box somewhere. Sadly, P&L fit is toast. Will get it restored though.
Sep 24, 2011, 10:59 PM
Registered User
Fiery, looks like it may have had an option for a second needle valve assembly, making it a two speed for RC.
It's a real shame when some one takes pliers to "bite" the engine parts. I get too agitated when I come across those and don't even consider them.
John
Last edited by JohnAV8R; Sep 24, 2011 at 11:00 PM. Reason: across
Sep 25, 2011, 12:49 AM
Registered User
earlwb's Avatar
Well, i figure if it is dinged up from plier marks, and if it is fixable, it'll make a good runner as you can't mess it up much more, unless you crash it or something.
Sep 25, 2011, 03:18 AM
Closed Account
Is this a Diesel - if so, what is that thing on top of the cylinder ? BOB
Sep 25, 2011, 09:15 AM
Registered User
To me that looks like a diesel and the arrangement on top apart from manual altering of compression would allow for in flight tweaking as well (through radio off course)
Last edited by mchandrayan; Sep 25, 2011 at 09:15 AM. Reason: formatting error corrected
Sep 25, 2011, 02:21 PM
Registered User
Reginald's Avatar
Quote:
Originally Posted by Twin-Stack View Post
Is this a Diesel - if so, what is that thing on top of the cylinder ? BOB
This is an engine made by Jan Garcic. You will recognise the shape on my website, there's a geared V-twin Garcic on there somewhere. Never seen this system on any engine, if selling it I am interested.
Sep 25, 2011, 04:52 PM
Dieselized User
gkamysz's Avatar
It's basically a throttle by controlling compression. Davis actually has a similar idea on their .049 head, which wasn't popular either.

Greg
Sep 26, 2011, 09:11 PM
Time for me to Fly...
Mr. Wiz's Avatar
Here is one you don't see too often. In case you are wondering but don't want to click, it's an Enya 41 4C Diesel. If I had not just bought the Webra T4-.90 I'd be trying to add this baby to my collection.


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Diesel Engines Aeromister Engines 15 Aug 23, 2016 10:57 AM
scale model of engines dw1122 Life, The Universe, and Politics 4 Apr 11, 2016 11:39 AM
Discussion Need help with two diesel engines ! cosmin Engines 4 Apr 18, 2014 08:18 PM
WTB-Model Diesel Fuel slogo Aircraft - Fuel - Airplanes (FS/W) 3 Nov 13, 2004 10:42 PM
diesel engines wyflyer_55 Fuel Plane Talk 7 Apr 22, 2002 03:45 AM