Logo
Builders' Plan Gallery  |  Hip Pocket Web Site  |  Contact Forum Admin  |  Contact Global Moderator
September 15, 2019, 11:58:35 PM *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with email, password and session length
 
Home Help Search Login Register
Pages: [1]   Go Down
Print
Author Topic: Irvine .20 Blackhead  (Read 827 times)
0 Members and 1 Guest are viewing this topic.
ama353
Nickel Member
*

Kudos: 0
Offline Offline

United States United States

Posts: 2

Topic starter


Ignore
« on: May 29, 2013, 02:56:22 PM »

Anyone here know what thread the head and back cover screws are?  Thanks!

Dennis
 Smiley
Logged
adanjo
Silver Member
****

Kudos: 3
Offline Offline

Japan Japan

Posts: 123



Ignore
« Reply #1 on: May 30, 2013, 05:52:12 AM »

Can't you remove the screws and/or you don't have any allen wrenches, right?
Aki
Logged
ama353
Nickel Member
*

Kudos: 0
Offline Offline

United States United States

Posts: 2

Topic starter


Ignore
« Reply #2 on: May 30, 2013, 02:55:56 PM »

I'm replacing the screws.  They seem to be an oddball thread - not 4-40, smaller than 3M but not 2.6M standard.

Dennis
Logged
adanjo
Silver Member
****

Kudos: 3
Offline Offline

Japan Japan

Posts: 123



Ignore
« Reply #3 on: May 31, 2013, 03:45:08 AM »

Interesting and curious.
Then, it may be 3-48 though I cannot believe.
3-48 is the same size as 2.5 (2.6)mm and the thread is coarser than 2.5mm.
And, what size of wrench did you use to remove the screws? You may be able to find whether the thread is inch or mm from the wrench size.
I am sorry that I cannot help you.
Good luck, Aki (had thought it must be 4-40)
Logged
TimWescott
Platinum Member
******

Kudos: 14
Offline Offline

United States United States

Posts: 1,004



Ignore
« Reply #4 on: June 01, 2013, 07:36:14 PM »

Eeew.  How old is the engine?  There's a British standard for small machine screws -- "BA".  If it's older than the mid 1980's it may use them.  You might want to Google it and see if any of the sizes look right.
Logged
kiwibrit
Bronze Member
***

Kudos: 0
Offline Offline

United Kingdom United Kingdom

Posts: 73



Ignore
« Reply #5 on: August 09, 2013, 06:07:11 AM »

My (non Blackhead) Irvine back cover screws are UNC 4-40.
Logged
Pit
Palladium Member
********

Kudos: 129
Offline Offline

Germany Germany

Posts: 5,507


aka staubkorb


WWW

Ignore
« Reply #6 on: August 28, 2013, 09:10:07 AM »

Peter Chinn did a review in M.A.N. in the Aug. 1985 issue.  I don't have the mag anymore, but there is a website that has a lot of mags digitized, or maybe someone still has a copy.

Chinn's articles were VERY complete, and IIRC, had even the thread types listed - especially as the Brits used a variety of "strange" sizes Roll Eyes.
Logged

A Dedicated Convert to:
WWWoFF (Wonderfull Wacky World of Free Flight)

Comparing Spammers to a pile of organic waste is an insult to the organic waste!
Konrad
Titanium Member
*******

Kudos: 38
Offline Offline

United States United States

Posts: 2,162


Measure twice cut once



Ignore
« Reply #7 on: August 28, 2013, 07:39:50 PM »

Here is a site that has a lot of old reports on engines. I don't know if the Irvine discussed here is included.
http://sceptreflight.net/Model%20Engine%20Tests/
Logged

Cut it twice and it's still too short!
ffkiwi
Gold Member
*****

Kudos: 20
Offline Offline

New Zealand New Zealand

Posts: 505



Ignore
« Reply #8 on: January 27, 2014, 12:02:50 AM »

I'm pretty sure you'll find them to be 4-40. This may sound surprising for a British engine-but Ron Irvine was for many years a major K&B distributor before he started manufacturing his own designs-in this included assembling K&Bs in the UK-including some model variants that were not made by K&B itself. This close relationship continued for many years even on a reciprocal basis where some of the US made K&Bs were equipped with the Irvine carb ex factory. Given that history it is not surprising that Irvine engine tend to use US threads rather than metric. The BA system-while typically used on many British engines of earlier years had fallen into disfavour by the 80s, after metrication was officially adopted in the UK.

ChrisM
'ffkiwi'
Logged
mjmccarron
Silver Member
****

Kudos: 5
Offline Offline

United States United States

Posts: 149




Ignore
« Reply #9 on: June 21, 2014, 12:12:01 PM »

I have two Irvines. Both use 4-40 but they are mid 1980's or later.
Logged

Light travels faster than sound. That's why some people seem bright until you hear them speak.
Pages: [1]   Go Up
Print
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!