Cox Engines Forum
You are not logged in! Please login or register! Guests are limited to posting in the "General Questions (Guest Posting Allowed)" section only. Becoming a member is fast, easy and FREE!


Log in

I forgot my password

Search
 
 

Display results as :
 


Rechercher Advanced Search

Latest topics
» Cox .020 Skycopter fuel tank replacement
by NEW222 Yesterday at 11:08 pm

» Vintage U control tether car
by Mark Boesen Yesterday at 10:32 pm

» If you thought that USPS was bad ...
by 944_Jim Yesterday at 8:53 pm

» The new W-196 arrives......finally
by crankbndr Yesterday at 8:42 pm

» Ronnie's engines
by Cribbs74 Yesterday at 8:27 pm

» Out of ideas - Help :(
by roddie Yesterday at 8:08 pm

» Cox Engine Forum Speed Contest 2018!!!
by getback Yesterday at 5:17 pm

» .010 Freeflight
by Ken Cook Yesterday at 4:55 pm

» CEF Honors All Who Served
by GallopingGhostler Yesterday at 1:16 pm

» Question re. Helldiver fuel tank
by Cox International Yesterday at 11:31 am

Cox Engine of The Month
November-2018
1/2A Nut's

"Speedy Teedy .020"



PAST WINNERS
Speed Contest 2018
CEF Traveling Engine

Win This Engine!
The Traveling Prop
Gallery


World of Aviation

Pee Wee / Thimble Drone 0.020 piston reset

Go down

Pee Wee / Thimble Drone 0.020 piston reset

Post  Harjit on Tue Jul 10, 2018 7:35 pm

Just bought one and at TDC, it feels like the piston is not moving but I am able to turn the crank through it. Sorry I don't know how to describe it better.

I purchased a piston reset tool from Cox International but before I use a tool I have never used before, I wanted your input.

Some of my questions:
1) How do I know I'm done?
2) When "tapping" the reset tool, I'm worried that if I don't tap it hard enough, it won't do anything. If I tap it too hard, it will be asymmetric. Is this a real concern? Or put another way, I think it will be best to push in all around the socket.

Thanks in advance!
Harjit
avatar
Harjit
New Member
New Member

Posts : 1
Join date : 2018-06-20

View user profile

Back to top Go down

Re: Pee Wee / Thimble Drone 0.020 piston reset

Post  Ken Cook on Tue Jul 10, 2018 8:38 pm

As with any resetting, do this on a solid surface. Either on a concrete floor on top of a piece of steel or on top of a anvil. Make certain the joint is clean of oil. You want to transfer the shock to the joint and not into everything else. Use a small ball pein. This isn't a job for the 24 oz. hammer. Make certain that your setting tool is as square as you can make it to the work.

You don't want to over do this. Each shot should be accurate and not hard. I like to give it a shot, rotate the tool 180 and give another. Keep rotating the tool on every shot making certain the rod is properly engaged in the tool allowing for full contact on the socket. I check repeatedly for play. Just keep tapping accurately and not hard. Obviously , you don't want to overdo this and the .020 is quite small so being cautious to how hard is critical. After a few taps you should note that the clearance is tightening up. This process can take a few minutes. This shouldn't be rushed due to heavy hitting not to mention the difficulty in obtaining spare parts should something go awry. Heavy hitting or out of square shots can result in the crown of the piston mushrooming. The piston should go back into the cylinder as smoothly as it was removed. The piston is harder than the cylinder so if a problem occurs, your going to be in search of a piston.

Don't concentrate on removing all the clearance in the rod joint. Having a slight bit of movement is better than none. Assuming all went well, you should be able to rotate the piston without binding on the rod went the rod is splayed to either or side.
avatar
Ken Cook
Top Poster
Top Poster

Posts : 3266
Join date : 2012-03-27
Location : pennsylvania

View user profile

Back to top Go down

Back to top

- Similar topics

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