RE: CMP BF109F BUILDING THREAD
 

Assuming the spoiler worked in unison with the flap to allow air through the glycol cooler and when the flaps come down it follows. To accomplish this I will probably install separate servo for spoiler. Here is my first pass at how to work out the slaving/mixing requiring 8 channels. I’ve never mixed before so I have no idea if this will work.


Mix1:
Aux2 (inner flap) => flap (outer flap)

Mix2:
Aux3 (spoiler) => Aux2 (inner flap)

Mix3:
Aux2 (inner flap) => throttle

Mix4:
Aux3 (spoiler) => throttle

Kahlog, tell me more about this match box? Here is the problem as I see it The inner flaps and the spoiler were a direct outgrowth of complaints from pilots that they had to take their A, B, C, D, E out of auto cool to shoot because if it moved when they were firing it moved the plane ever so slightly and cost them ammo. So the inner flap and the spoiler have to work in unison to open like a clam shell, while the outer flap stays unmoved. That pushes me to that 8th channel, again, I have never paid attention to mixing, or match box’s or the like choosing rather to do it mechanically.

Joe

RE: CMP BF109F BUILDING THREAD
 

It comes down to how much I want to crash.

For me its as little as possible.

I always do the math.

109 $300
OS 108 $80
rertacts/tires from way back $50
muffler, made it. maybe $15 in scrap alum
spinner backplate, made it $8

total out $453.00 to get flying, so say $500.00

Radio equipment, (JR 9303)I don't count because its the most portable component. , but I saved there too. (Nitroplanes metal gear MG995 servos, $8.00 each in bulk)

I have always tried to stick with my rule of " its not how much you make , but how much you keep". I keep a lot.

99% of these are out of China. Its not "you get what you pay for anymore" for the most part.

Steve

RE: CMP BF109F BUILDING THREAD
 

Hi Steve,

Have you had good luck with those MG995 servos? I've been curious about them and even went so far as to purchase a few of the PPP servos here from RCU's classifieds. I had some installed my Ziroli zero (ailerons and flaps) then re-thought the servo move and installed my beloved Hitec 645MG's (known good servos) instead.

Just wondering what your experience has been with them because they appear to be good strong servos that center well, have a coreless motor, nicely made metal gears with zero slop, and dual ball bearings supporting them.

I'm afraid of the get what you pay for syndrom.;)


Sonny

RE: CMP BF109F BUILDING THREAD
 

The matchbox unit will move all 4 flap pieces in unison at the same time. Each servo can ne indendently adjusted for travel movement, end points, etc using the matchbox and all just using one channel.
Now...with the spoilers, you can use the radio to mix them to the flap channel if you want and have them move in unison as well when you activate the flaps(this is assuming you use separate servos for the spoilers). I have mine this way and its on a toggle switch where I can turn the mix on or off. So I can deploy the spoilers if i want, but I dont have too even if the flaps are deployed.

RE: CMP BF109F BUILDING THREAD
 

These exact same servos are offered on line by some for almost $40.00.( ebay, others) My friend has used them with out problem for a while. The CMP 109 is the first model I have used them in. At this point I have no problem with them. I bought 10 of them from Nitroplanes for around $90.00 when they had a deal going.

Try them in a less critical location.

Steve

RE: CMP BF109F BUILDING THREAD
 

does anyone know which to use to bond to the fiberglass alphatic resin or epoxy?

Joe

RE: CMP BF109F BUILDING THREAD
 

Hi

Epoxy is not a good idea to use on polyester resin. I use polyester resin on polyester. Urethane glues can also work (gorilla types). Silicone can also work in flexible area.

Polyester can work on epoxy, but not epoxy on polyester. Sand and wipe clean

CMP fuses are polyester at this point.

Steve

RE: CMP BF109F BUILDING THREAD
 

bond to the fiberglass alphatic resin or epoxy?

is this for repair ?? or adhesion?
I am asking because for repair the #1 suggested product is "evercoat " sold at bodyshops and car paint stores

RE: CMP BF109F BUILDING THREAD
 

Are you guys sure the CMPro kits are polyester resin? I built and repaired a couple of Byron kits and they are polyester. I believe but might be wrong that the CMPro kits are FRP, which is fiber reinforced plastic.

Loopman

RE: CMP BF109F BUILDING THREAD
 

I agree, the CMP fuses don't feel like polyester resin.

RE: CMP BF109F BUILDING THREAD
 

I used epoxy on the CMP fuse without any problem

RE: CMP BF109F BUILDING THREAD
 

I'm asking because i want to block the engine up instead of use the supplied vibermount. as long as i'm blocking it up i might as well push it out to the fuse and tie it in. i'd hate to doo all the work and have it all break away. i'll get some garilla glue, does lowe's sell it?

Joe

RE: CMP BF109F BUILDING THREAD
 

Guys.

First, for the price, what you get you can't beat CMP, if your cautious and know the weak points.

The fuses of epoxy and polyester can feel the same. I can't tell by feel. Does a Corvette feel like epoxy or polyester. One easy method of "testing" what resin your model is layed up with, is just sand, or when you cut, or grind the fuse, i f it smells like Bondo, or a boat factory, its polyester.

Epoxy can bond to polyester in the short run. Life expectancy for the bond with vibration may be low. CMP is not using quality polyester resin, wait till summer and your fuse is in direct sun light on a hot day the bond may de-laminate. Somehow polyester has a waxy surface that epoxy cannot bond well with. Even with sanding.

Can it work, sure, but the potential problem is there.

On the other hand, polyester does bond to epoxy.

Corvette=polyester, back on the day anyhow.

Steve

RE: CMP BF109F BUILDING THREAD
 

Todd I paid $NZ500 for this plane that works out too about $US250 so I am not sure where you got your price from? as for quality I can only look at the BF109F model as supplied with all the mods everyone has done to just get it to fly then look at what is involved in the P51... take a looks at the parts on my thread including the high quality spinner This will be the last I post in this thread as I dont want to ruin the thread with a pissing match, FOR ANYONE WHO IS CONSIDERING BUYING THIS PLANE...... think carefully about what you are getting and be prepared to spend a lot of time modifying the hardware supplied with the plane here is a quick sum up of mine and others mods.... 1 TAIL WHEEL CONTROL the ball link just falls off, you will need to file the ball flat and use a different link 2 SPINNER QUALITY treat this very carefully as it is quite brittle and most people are replacing theirs 3 ELEVATOR CONTROL RODS not the best setup a set of wires Ved on the end of a fork can cause problems in flight with twisting and vibration you will need to replace them and/or provide extra supports in the body 4 LANDING GEAR RAILS be prepared to beef them up as they are quite weak, some have had them break on a hard landing 5 CANOPY treat this like its made out of crystal there has been a number coming out of the box broken (mine was) and some breaking while installing 6 RUBBER ENGINE MOUNTS throw them away and get better quality ones or hard mount your motor, 7 ENGINE MOUNTING BASE make an extra engine support as the ply is a little soft and with the holes close to the edge could well fail, some people have also beefed up the engine mounts around the edges 8 THROTTLE SERVO do not mount it in the engine bay as the manufacturer suggests as its too hot too oily to do safely 9 ELEVATOR HINGES beware when drilling the holes as the pins are too long and will break through your covering 10 CONTROL LINKS they use quick links all over this plane throw them out and replace them with a better quality one same with the plastic ones COVERING this is a matt finish so beware with glow fuels it will get messy over time with the fuel oil soaking into the ccovering also the covering is a painted finish not built in to the covering thats it I guess at least any future buyers can be informed

RE: CMP BF109F BUILDING THREAD
 

If i had to do it all over, i would not buy this plane, there has been to many quirks, and alot of modifications i have had to make, Everything Snappa
said is TRUE! This plane is very fragile and i am sure it wont endure alot of flights without falling apart!!!!!!!!!!!!!!!!!!!!!!!!!!!
I am not sure i want to maiden this plane because i have very little confidence that it will hold together. and thats no joke!
Sorry to bring everyone down but thats my final thought about this plane.

RE: CMP BF109F BUILDING THREAD
 

For me its also the cost of freight to NZ from the states the original me109 cost me about $NZ650 delivered to my door, now its up around $NZ800 with the crap exchange rate and this plane is not worth that much

RE: CMP BF109F BUILDING THREAD
 

The prices I quoted are what you can get them for in the US. In your case Snappa the CMP planes are not near as good a deal. I don't find too many ARF's in the price range of the CMP that don't require most of the mods you mentioned. The paint on my other models have held up well. I spray on a coat of satin polyurethane if I want the finish to be even more glow resistant. For the price I paid (in the US) I am still convinced the plane is a good deal.

As for the plane being Fragile, I think it will hold up as good as any. I have a few CMP planes, and they have all held up well. Any plane built sturdy enough to survive a crash will not fly well, so I don't consider it fragile if I bring it in hard and something breaks.

RE: CMP BF109F BUILDING THREAD
 

I got robart hinge pints, both the 1/8 and 3/16. well I decided to test the smaller one and it held up very well. It was about the same failure point as the one I posted (from the kit) which I expected. This is subjective of coarse. But the big difference in my mind was that the failure point came on so slowly that I was able to stop before the pin turned so you could see the elongation of the plastic and the slight turning of the hinge.

Then I tried the bigger hinge I was expecting this to put the kit hinges to shame. As soon as I started pulling it failed! Both knuckles, without the pin in them in the pic’s, split with out warning. So I have to say the kit provided hinges are just as good as robart hinge points. My plan is to use the kit provided hinges with the control horn on them and use robarts every were else. Once I get a count of what I need I’ll break a few more robarts hoping the first one was a fluke.

I’ve been looking at polyester resin on the internet, but what store can I walk and buy this stuff? A place they sell/repair boats?

Joe

RE: CMP BF109F BUILDING THREAD
 

pladin

Lowes or home depot out here have it.

Too much work on an arf or a big head start???

I believe it depends on building school you are in or came from. I have built countless kits, scratch built, and fabricated my own composite models. This is why I see these budget priced arfs as bargains, currently the 109 is $260.00. Other models of the same size are around $450,550 and more.

Even if i changed all the hardware in a CMP model, I would still not have another $200.00 in it. Plus its suppose to be fun to build a little.

A lot of the scratch build guys I know can open an arf box and see the weak points in the first few minutes. If one lacks this type of building skill, don't blame the arf model. They are not perfect, they are mass produced.

anyway.

Get some of them up and see.

Steve

RE: CMP BF109F BUILDING THREAD
 

I have to agree with you Steve , I did splurge on a KMP corsair and I do see some of the quality aspects , but most of my planes are CMP and I have been very happy with the quality and flying aspects of the planes .The 73" p40 is one of the best flying P40ties you can fly , much easier to fly then the 65" Gold Edition P40 .
I have been tinkering with a CMP Fw190 for about a year , a total bash , air power canopy , Sierra Fw190 gear all around ect , but because I purchased the plane so cheap , that its make the upgrades easy !!!
I have built a ton of kits from a box of wood and now day while I am still so tempted I get pulled back into the value aspects of ARfs .
Example , red box P40 (box of wood)on ebay for $179 , or BH models P40 for $169 , the BH Models P40 ARF makes one hell of a start for a nice bash .
My new CMP Bf109 is in my opinion is a great value and high on the cool factor , ya I do worry about the sun on the fuse ect but hey ice cream melts fast in the sun as well , but its damm good while it last :D

RE: CMP BF109F BUILDING THREAD
 

I have to agree. Some ppl are just being a little harsh on this plane. Its a great looking plane and the price is a great start to get a decent reliable flying plane. Most arf's require some form of modication. Even the KMP planes require you to think a little bit. Is this a hangar9 type build-it-in-two days plane? No of course not, but no Hangar 9 arf comes even close to being scale.

For me, yeah I did buy a 2nd one because it is a super value and Im not worried about it falling apart at all. Thats just stupid. If you reinforce areas, then you wont have anything to worry about. Almost any arf requries that anyway.

RE: CMP BF109F BUILDING THREAD
 

Greetings From Finland

"In the land of blind, even one eyed fellow is king."

When rating this plane plane you also have to remember that this is only 109 F (G) ARF available. (At least that I know). At least half of score different sizes of E:s. G was most produced version of 109:s and only one ARF and some kits. Total mystery for me.


Old Erkki

RE: CMP BF109F BUILDING THREAD
 

I'll bet its the spinner size. Well, if you want it to look a little right anyway.

Steve

RE: CMP BF109F BUILDING THREAD
 

I agree with scalecraft. I like to take the ARF as a start. Then I try to make it as good as my experience and my budget let me.
I took the trottle servo out of the engine room. See the pictures which also include some of the fuel plumbing.

Regards,

Eric Schumacher, Netherlands.

RE: CMP BF109F BUILDING THREAD
 

And when I'm at it, here is a picture of the electronic heart, waiting for the transplant. The device gives a 6v current from 2 seperate 2c lipo's. It also prevents overloading the receiver, as the servo currents don't pass the receiver.
I also put in an fuel valve for easy fuelling. The other knob showing is the mixture control.