peternj

My Feedback: (5)

Owen, the only concern I would have about the ultimate being left outside, or any model for that matter, is that when it dries it will have a tendency to warp. you will need extra care in securing the wings and fuse on flat surfaces to ensure they dry straight. as for the plans send abbot an email ([email protected]) or PM me and we'll get them out to you in digital format, the package has everything you need to build it from scratch.

peternj

My Feedback: (5)

ok, so i have an unrelated question, well kind of related... I threw a connecting rod on my Magnum .52 four stroke. Any one have advice on how to swap it out and still get the timing righ?

Ownthesky2010

Thanks for the advice peter. I will send you a pm. The top wing has dried out dead straight but the bottom is still very wet so I will clamp it down for now.

Twin_Flyer

My Feedback: (4)

Sounds like I need an updated package then! [email protected] when you have the time.

Bill S.

pushinoldrc

My Feedback: (46)

Hi all,
I have been lurking in this thread since close to the beginning and love all the pics and information. I have not started my kit yet, as other projects are still ahead of my Ultimate build. Namely my wife's TF GS Corsair.

As to your Magnum, I believe the cam gear should have a mark on it to show alignment with the crank, and it should line up when the piston is TDC.
Before completely disassembling the engine, bring the piston to the top of the compression stroke. The rockers should be at the same angle with the valves closed.
Then, remove the cam cover and look for the timing mark. OS uses a dot or punch mark on the face of the gear. You can also look for an alignment mark on the crank, but I have never been able to locate one at the cam gear.
You should be able to use this as a reference when reassembling the engine.
Years ago, I flew my trainer through an oil derek, and the OS FS 61 hit one of the braces. The impact sheared the cylinder off of the block, and I ended up restoring that engine to running condition. I was able to replace the piston pin through a screw hole in the cylinder and did not have to remove the crank, therefore omitting the necessity to time the cam.
Good luck, and let us know what you find.
Bryan

peternj

My Feedback: (5)

thanks Brya,

The problem I have is that the journal on the crankshaft where the connecting rod connects to it (the crankshaft) failed. The piston is not attached to the crank so my only point of reference to TDC is the position of the crank while looking back at the rear of the engine with the back cover removed. I guess I can reassembe the valve train to determine TDC when both valves are closed. And I'm having a problem locating that punch mark is it a small dot?

peter

pushinoldrc

My Feedback: (46)

I will be disassembling one of these engines this weekend to replace a worn ring, and will post what I find for timing references.
B

Twin_Flyer

My Feedback: (4)

Timing on a Magnum is the same as an OS four stroke.

Look here: http://www.rcuniverse.com/forum/glow...-timing-2.html

Bill S.

peternj

My Feedback: (5)

Bill, thanks for that reference! I read the timing procedure in the manaul, but these pictures are worth a thousand words. Yes pun intended.

Twin_Flyer

My Feedback: (4)

There is a CG Ultimate on eBay right now, looks like a 2 day auction with no reserve starting at $85!

http://cgi.ebay.com/ws/eBayISAPI.dll...E:B:SS:US:1123

Its not one of my auctions, just passing on what i found...

Bill S.

tailskid

My Feedback: (34)

Thanks for the head's up!

abbott915

My Feedback: (1)

Hello everyone,

I've started laying out the parts in cadd, so if anyone else out there has cadd and the parts or tracings, please email me at [email protected] and we can collaborate.

I've practiced on some of the easier smaller parts like the tank pan and a couple of the formers since they were basically square.

I'm working on the fuselage since they are the bigger harder parts, and have the fuse top done and am starting on bottom next. The sides shouldn't be that hard since they are the same, so once I get one done, I have the other.

I still have to print them and then lay the original part on top to make sure they are correct, and make any adjustments if needed.

If anyone has a laser cutter that can help me with colors and how to set up the drawing for the cutter, that would be great also. I know there are colors for the cuts and for the lettering or text, and then I've also read about leaving a little bit uncut so the pieces stay as a "punchout" style, versus just fall out.

I'll update as I progress.

Twin_Flyer

My Feedback: (4)

I'm sure that's a lot of work abbott but will be nice when finished!

i know I want a set!

Bill S.

peternj

My Feedback: (5)

you are the man Abott!!

peternj

My Feedback: (5)

Bill (twin flyer)

Thanks for the advice on the Magnum. I replaced the crank and set the timing it was a breeze, the marks and photos i had for reference helped too. I'm running into a problem where I get complete blow by into the crank case. When I was spinning the engine, i feel significant amount of air flowing through the breather nipple. placing the finger over that niple returns the compression feel to normal. I suspect that I have a bad sleeve, ring, and piston. I wonder what could have caused the failure of the crank while in the air. I did have a couple of prop strikes on landing but the engine ran. The only thing I suspect is an overheat condition that seased the piston causing the journal on the crank to fail. when engine cooled the piston moved freely again. I inspected all the parts and they appeared ok.

any ideas what it could be. the cost of a new connecting rod, sleeve, ring, piston, and possibly valves (if they are bent) and push rods quantifies a new motor instead. I was hoping for a cheap fix but now I am curious to figure out what the failur may have been and the cause of the blow by and why.

any ideas are welcome

BTW, the ultimate is flying well.....

abbott915

My Feedback: (1)

I really enjoy the cadd work and have missed if for years. Long ago I used to be a civil cadd driver, then did more design than cadd work and have really enjoyed getting back into it. Only problem is that one hour turns into two, then into four and the next thing I know the suns coming up!!

I don't get to do cadd work at my job anymore, so this is pure joy!

georgewaldrop

My Feedback: (28)

This would be great!...I would definitely like a set when you get them done. It would be great if you and Peter could collaborate and include cad templates for the "modified" pieces set out in this thread, regarding the cabane mounting and such...Thanks for your efforts!

Twin_Flyer

My Feedback: (4)

Peternj,
There should always be air coming out of the breather nipple. As the piston goes up, it will suck air in through the nipple and as the pistons goes down, air will go out. The small engines normally have some blow bly as thats how the oil lubes the big end/crank/bearing/cam/etc.

Did you remove the picton from the cylender and give everything a real good once over? if not do it now! there shold be no scratches in the cylinder or the piston. Also not how the piston is in the cylinder as you want to be sure it stays that way! if there are no bad marks on the cylinder (doesn't catch a finger nail) maybe just a new ring is all that is needed. if the piston did seize in the cylinder once there should be an indication of that and yes, it would probably be a parts engine at that point. I have never had any of my engines break the crank so...

Bill S.

abbott915

My Feedback: (1)

Good idea George. Peternj, not sure if that is possible, but if you do have some of your mods that you could pdf me, I'll be happy to include them.

I'm working on the fuse top and bottom and making sure that they are straight, with the correct tab and slot depths and widths. Also that the formers are the correct width and height. I'm finding that the fuse top and bottom have some "anomalies", and I'm working on straightening them out. Hopefully this will make for a better build.

I hope to have all the lite ply parts done this upcoming weekend. They are mostly all laid out, now I just need to make small adjustments to them so they all fit together.

I've only built one of these, and it was a couple years back, so I'm really having to think back through the process and make sure that all the math adds up between the formers, sheeting and fuse sides.

The kit I have borrowed is surprisingly not very good as far as the cuts being straight when you look down the sides, but we'll get them straightened out.

peternj

My Feedback: (5)

abott, unfortunately I do not have the mods traced I did them on the fly. They include adding additional former doublers to the fuselage to support the cabane mounting and bracing to side of the fuselage to carry the loads to the site of the fuselage... That's why I include the build thread in a document. I think the next person who builds it and makes the mods could possibly provide us with the parts listing....

Atlanta 60

My Feedback: (18)

I recieved the info package a week or two ago and wanted to say a great big thanks to you guys for the Awesome information and efforts in preserving it!!! Thank You!!

I have flown my CG Ultimate a lot this season and have really enjoyed it, what a wonderful plane!!

A few weeks ago I kinda let the bipe sit on the sidelines while I concentrated on flying and tweeking my (50cc) Great Planes Christen Eagle II....I was getting comfortable withe the Eagle II and thought it was flying pretty well...Then I had an aileron servo failure followed by another (cheep Power HD servos) so I decided to ground the Eagle until I can replace all the servos with Hitec's.....I charged up the Ultmate and took her flying and Boy!! I really realized how fun this plane is!! After the couple of weeks off from flying her plus being back to back with the Christen Eagle it was a real heads up comparison...The Ultimate wins hands down...Such a blast!!

edit:
I pulled my YS 120NC off the bipe as I want to put new bearings in it so I stuck my YS 91AC on it...I test ran the engine since it's been sitting on the shelves for a long time and need to get an exhaust for it and she'll be ready to go flyin'...

Have Fun...

punkindrublik

Somebody grab it quick -

http://www.rcgroups.com/forums/showthread.php?t=2012751

peternj

My Feedback: (5)

twin_flyer,

So i just said what the heck and started that magnum .52 that i had concerns with... well it runs and idles... and it flies the plane. I can't get it to run faster than 9,200 rpm but thats no problem it only did 9,600 before with a APC 12x6. So im just gonna fly it till it blows up again. but i still cant figure what cuased the journal to fail like that. some members at the field said it may have been a void in the casting that fatigued and failed..

any ways all good thanks for all the notes

Twin_Flyer

My Feedback: (4)

peter,
High 9K rpms sound good to me!

Did you check the valve lash while working on it? Also, only use the OS type F plug in that (or any four cycle) engine.

Bill S.

dmarusa

What Bryan says here is correct about the timing mark. It is important to know that the mark should not be straight up, but inline with the pushrod tubes.... about 11:30.