I'm going to document the Cromwell rebuild on this thread.  During the 
build I hope to highlight what worked, what didn't, and what will be new 
for 2014 on the venerable combatant.   For those that don't know, the 
Cromwell has pretty much battled in most US battles since 2005 and is 
little changed since new.  Those that know my battling style, know that I'm 
not exactly a Sunday driver, so when I let this beast out of its cage, the 
tank sees its fair share of bumps and bruises.  This will be the first 
major overhaul and It will be interesting to see how the plywood 
construction and my design choices have held up over the past eight years.

First pic, here's the hull stripped of everything with a new coat of paint. 
 I'm glad to say that there was no structural issues with the hull.  All 
the glue joints are still tight and IMO proves that well executed plywood 
construction is a very viable option for these models.  At this point, I've 
installed a new set of 1/2" bearings for the suspension arms.  These 
bearings are the flanged stamped steel "wheelbarrow" type.  The old 
bearings still sort of worked but were gummed up with mud and rust.  I'm 
going to think of a way to seal these a bit better for the next eight years 
of use.

<https://lh4.googleusercontent.com/-zyc90yqA8gU/Uo-BkBy895I/AAAAAAAAAWM/8d1-elsyMAo/s1600/2013-11-22+07.50.17-B.jpg>

Here's the engine bay.  This area had an almost constant coat of oil from 
the chain drive.  I'm glad to note that the liberal coat of Titebond II 
glue that this area was sealed with was not effected by the oil one bit. 
 Astute observers may note that gray epoxy plug in the lower center of the 
rear panel.  This is were the safety cutoff switch used to be mounted.  The 
switch in this location was prone to shutting off when reversing in thick 
brush (not a good thing).  The switch will be relocated elsewhere.

<https://lh6.googleusercontent.com/-ma0fqJsCoYY/Uo-Dtg4gzpI/AAAAAAAAAWY/vdB7TiPDlWE/s1600/2013-11-22+07.50.32-B.jpg>

Here I'm highlighting some past repairs.  The red circled area is a section 
that was cracked and pushed upward when the Cromwell's right front idler 
hit an object at full speed (a paper pinata at a Daneville event, go figure 
;-).   Luckily it was a clean break and it was epoxied back together and 
has held ever since.  The blue boxed area is an additional layer of 1/4" 
luan plywood that was epoxied in to thicken this area up.  The original 
single piece of 1/4" luan in this area was punctured by a tree root. Lesson 
here is that areas subject ti impact, 1/4" plywood is not enough.

<https://lh3.googleusercontent.com/-_ssWO8Rcm5A/Uo-HDTCaPAI/AAAAAAAAAWk/Al1PMS1H37w/s1600/2013-11-22+07.51.41-B.jpg>

That's it for now.  The next installment will be the refurbishment of the 
suspension and road wheels.

Steve Tyng


-- 
-- 
You are currently subscribed to the "R/C Tank Combat" group.
To post a message, send email to [email protected]
To unsubscribe, send email to [email protected]
Visit the group at http://groups.google.com/group/rctankcombat

--- 
You received this message because you are subscribed to the Google Groups "R/C 
Tank Combat" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
For more options, visit https://groups.google.com/groups/opt_out.

Reply via email to