SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Aug 23, 2005, 09:08 PM
WCB
Registered User
NC
Joined Aug 2005
1,104 Posts
Cermark Pitts

The Cermark Pitts manual calls for 1/2" aileron throw on low rates and 7/8" on high. I can only get about 5/8" max. The trailing edge of the wing has a lip of sheeting that sticks out about 1/8" top and bottom in the aileron slots and the ailerons hits it hindering the deflection. Has anyone else run into this?
WCB is online now Find More Posts by WCB
Reply With Quote
Sign up now
to remove ads between posts
Old Aug 27, 2005, 11:20 PM
PROBRO 194
texan's Avatar
Georgetown, TX
Joined Apr 2003
340 Posts
Did you glue in your ailerons yet? There is a design flaw with the ARF.
texan is offline Find More Posts by texan
Reply With Quote
Old Aug 28, 2005, 09:41 AM
WCB
Registered User
NC
Joined Aug 2005
1,104 Posts
Yea I already glued in the ailerons. I contacted Cermark and they told me to take a hobby knife and compress the lip 1/16". Since I can't do that now I guess I will have to live with 5/8" throws. That should be a plenty with 4 ailerons.
WCB is online now Find More Posts by WCB
Reply With Quote
Old Aug 28, 2005, 10:16 AM
PROBRO 194
texan's Avatar
Georgetown, TX
Joined Apr 2003
340 Posts
WCB,

Cermark needs to contact their distributers about placing a revision to the aileron hinging instructions in the kit. The hinge line is actually recessed into the leading edge of the alieron approx. 3/8". The hinge point holes must be notched at 45 degrees on both sides to allow full travel.

Are you close to finishing your Pitts? I hope to maiden my Pitts next weekend.
texan is offline Find More Posts by texan
Last edited by texan; Aug 28, 2005 at 10:46 AM.
Reply With Quote
Old Aug 28, 2005, 09:36 PM
WCB
Registered User
NC
Joined Aug 2005
1,104 Posts
texan,
Yea I know what you are saying about the hinges. I recessed mine and cut out for the throw. All I have left is to mount the engine (Saito 150) and fuel tank. I'm not sure about how the tank mounts with the strips and how the heck do you get to it w/o cutting the covering? I'm looking to maiden mine next weekend too. Let me know how your's does and I'll do the same.
Regards,
WCB
WCB is online now Find More Posts by WCB
Reply With Quote
Old Aug 28, 2005, 10:08 PM
PROBRO 194
texan's Avatar
Georgetown, TX
Joined Apr 2003
340 Posts
WCB,

The Saito 150 should be a perfect engine for the Cermark Pitts. I am using a Moki 1.35.

By the way, I did cut the covering to mount the fuel tank and reinforce the firewall. I installed a lite ply shelf below the cabane struts to support the tank. The fuel level is closer to the carb center.

Did you find the aileron control horn screws too short?

I decided to use Robart control horns, 4-40 rods, and a CB associates tail wheel assembly.

Good luck,
texan
texan is offline Find More Posts by texan
Reply With Quote
Old Sep 02, 2005, 12:09 AM
WCB
Registered User
NC
Joined Aug 2005
1,104 Posts
Texan,
Yes I used some different screws. The stock were too short. I used a Sullivan tailwheel on mine. The fuel tank was a pain. The spinner backplate is going to be about 1/8" too far past the cowl. The engine is as far back as it will go. I couild redrill the cowl mounting holes and move it forward some but then I'd have to fix the old holes and repaint. Too much trouble.
WCB is online now Find More Posts by WCB
Reply With Quote
Old Sep 05, 2005, 03:41 PM
PROBRO 194
texan's Avatar
Georgetown, TX
Joined Apr 2003
340 Posts
WCB,

Did you maiden the Pitts this weekend? I was able to maiden mine Saturday. It flew well but tended to nose over during taxiing.

Caution: I found a cabine bolt had fallen out during the flight. There are two pre-installed cabine bolts per brace. All of my bolts were loose. I recommend checking them before you loose your top wing!

TX
texan is offline Find More Posts by texan
Reply With Quote
Old Sep 06, 2005, 07:21 AM
WCB
Registered User
NC
Joined Aug 2005
1,104 Posts
Congrats on the maiden! I fell behind schedule and didn't get mine ready so maybe next weekend. Are you flying off grass and using the wheel pants? I fly off short but very thick grass and was wondering if I needed bigger wheels to be able to use the pants. Thx for the heads up on the cabane bolts. I will check them and probably put some lock washers in place.
WCB
WCB is online now Find More Posts by WCB
Reply With Quote
Old Sep 06, 2005, 09:31 AM
Speed Demon
GregG's Avatar
Antioch,CA,USA
Joined Dec 1999
12,322 Posts
Quote:
Originally Posted by texan
......Caution: I found a cabine bolt had fallen out during the flight. There are two pre-installed cabine bolts per brace. All of my bolts were loose. I recommend checking them before you loose your top wing!.....
All of your bolts were loose? It sounds like an excellent place to use nylock nuts. Thats what I did to my Christen Eagle.
GregG is offline Find More Posts by GregG
Reply With Quote
Old Sep 06, 2005, 10:29 AM
PROBRO 194
texan's Avatar
Georgetown, TX
Joined Apr 2003
340 Posts
Quote:
Originally Posted by GregG
All of your bolts were loose? It sounds like an excellent place to use nylock nuts. Thats what I did to my Christen Eagle.
Cermark should have used nylock nuts. The bolts are "built-in" as part of the pre-assembled ARF. I had to use a Dremel to remove some wood just to inspect the rear cabane bolts. Cermark used some thread lock compound, which apparently was not effective. I also installed a hatch below the firewall to inspect the front cabane bolts.

TX
texan is offline Find More Posts by texan
Last edited by texan; Sep 06, 2005 at 11:32 AM.
Reply With Quote
Old Sep 06, 2005, 11:41 AM
PROBRO 194
texan's Avatar
Georgetown, TX
Joined Apr 2003
340 Posts
Quote:
Originally Posted by WCB
Congrats on the maiden! I fell behind schedule and didn't get mine ready so maybe next weekend. Are you flying off grass and using the wheel pants? I fly off short but very thick grass and was wondering if I needed bigger wheels to be able to use the pants. Thx for the heads up on the cabane bolts. I will check them and probably put some lock washers in place.
WCB
I am flying off grass with the wheel pants and stock wheels. Our field is in rough condition now. My plane is slightly nose heavy which doesn't help the nose-over situation. I will begin moving the CG back on future flights.

Bigger wheels may help but the pants will not hold much more. I doubt that you can stuff 3.5" in there. I switched to Sullivan Lite 3" to reduce rolling resistance. The stock "raw foam" tires tended to become flat and pick up too much trash. I think harder tires may help.
texan is offline Find More Posts by texan
Reply With Quote
Old Sep 06, 2005, 06:04 PM
WCB
Registered User
NC
Joined Aug 2005
1,104 Posts
Texan,
The Saito 1.50 I am using weighs about the same as your Moki. The APC 17x6 prop is made of lead (feels like). I was worried about being nose heavy. Did you put the battery in the stock position? I am using a 2700 mah Nicad so i might move it aft if nescessary. I absolutely hate adding non-usable weight. The stock spinner is going to have to be cut A LOT to fit the APC. I don't look forward to that task.
WCB
WCB is online now Find More Posts by WCB
Reply With Quote
Old Sep 06, 2005, 07:01 PM
WCB
Registered User
NC
Joined Aug 2005
1,104 Posts
Texan,
I was able to pop the servo tray out to get to the aft cabane bolts. I'm glad I did that because the tray wasn't glued in there all that good. (Check yours!) The front bolts were pretty easy to get to. I am replacing all of them with 4-40 bolts, washer and locknuts. The stock bolts are metric and 4-40 is real close to the same size. Thanks again for the tip!
WCB
WCB is online now Find More Posts by WCB
Reply With Quote
Old Sep 06, 2005, 07:13 PM
PROBRO 194
texan's Avatar
Georgetown, TX
Joined Apr 2003
340 Posts
Quote:
Originally Posted by WCB
Texan,
I was able to pop the servo tray out to get to the aft cabane bolts. I'm glad I did that because the tray wasn't glued in there all that good. (Check yours!) The front bolts were pretty easy to get to. I am replacing all of them with 4-40 bolts, washer and locknuts. The stock bolts are metric and 4-40 is real close to the same size. Thanks again for the tip!
WCB

Sounds good, I'll check the servo tray.

I balanced per plans without the spinner. I'm using a MA 18x8 wood prop (pretty light). My receiver pack is a 5 cell 2500 Mah NiMh A size. I mounted the pack directly above the fuel tank... near the CG. I installed my throttle servo on the tray behind the firewall. When I receive my prop adapter from TruTurn, I'll move the battery pack to re-balance.

I also installed on board glow which has one 2500 cell mounted in the nose.
texan is offline Find More Posts by texan
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Video 60" Cermark Pitts S2B lmopar69 Fuel Plane Talk 2 Nov 22, 2006 08:56 PM
cermark pitts s2b highflyer8 Fuel Plane Talk 2 Jan 19, 2006 07:12 AM
Discussion cermark pitts s2b highflyer8 Batteries and Chargers 0 Jan 18, 2006 04:29 PM
For Sale Cermark Pitts S2A arf NIB phmx17 Aircraft - Fuel - Airplanes (FS/W) 0 Nov 28, 2005 03:45 PM