Starfire 60" all epp - Page 4 - RC Groups
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May 22, 2010, 12:36 AM
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cleansurf2's Avatar

From what I've read, the PW51 doesn't mind being loaded up with weight and performs well loaded. When I get around to a build, I'd like the option of balast though so I can adjust for conditions/application.

Really interested to see if you need to add lead to the nose to dial in your CG.

I'm not real sure on your mid mount regarding prop efficiency, especially with a high KV motor and smallish prop. Considering the weight of your gutsy motor you probably don't have much choice but to mid mount, unless you went an extended nose cone to balance CG or a heap of lead.

Excellent build thread so far. Thanks for all the pics and info. Will be watching with much interest.

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May 23, 2010, 11:43 AM
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MWCores's Avatar
Hi Phil,

Start CG at 7-3/4 to 8, with that size of motor I am sure you will have some adj. to do
PW-51 is a good one to load up, it is ment to go fast.
Build is looking good!!!!!!!

May 23, 2010, 02:11 PM
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pval3's Avatar
core beds are done
CF is sanded
Motor mount material is sitting ready to be cut out and routed
servos have been cleaned with alcohol to get any oils off and servo arms have been cut and sanded.
I am on my way to the beach for the week
see you all when I get back
May 23, 2010, 02:13 PM
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pval3's Avatar
We are going to have a McClain wing cores week at the beach!
I managed to fit the 36MCW, 48MCW and the starfire mid motor 48 in the car . . . amazing!
I am also bringing my very very old FMA Razor to try to teach my older daughter (5 in three weeks) how to fly)
Dont laugh guys, that was state of the art at one time . . one of the first epp type airplanes!
I STILL have a speed 400 with a paddle prop and (up until last night) nicads!
Jun 09, 2010, 10:37 PM
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pval3's Avatar
Hey Guys
sorry for the slow response. . .
I found a mount I think I may like for the Pulso outrunner. It is tight but it fits and it is a beam mount (like a gas motor mount) that I can bolt onto a ply plate to support the brute force of this motor or whatever else I want to put on it later (still looking).
Gathering pieces and parts and pooling thoughts now that I have the motor mount I need to do this the way I think it needs to be done.

I am doing my annual ground training in Dallass right now.
I am kind of out of the loop for the next few days.
I have a simulator ride in two weeks and will be inundated with that too so please hang tight . .
The building will be fast and furious once it starts as my window of opportunity is going to be very small with my work schedule for the next couple of months so I want to try to bag this out and get it done before the chaos really kicks in.
Jun 27, 2010, 11:31 AM
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pval3's Avatar
Here we go
a few hrs of trial and error to get the train a movin'
used gorilla glue amber to join the outer and inner wing panels

take the glue and make several very consistent trails of glue, not too much and not too little, better to go back after the fact to fill in than to over do it with this stuff as if it is over about 30% humidity, you are going to get a lot of foaming which will distort the joining of the panels.

Use a gloved hand and work the glue into the panel on both sides so that you have a nice even glue joint completely but thinly covered.

take one half at a time . . . this glue works fast so you need to concentrate on the task at hand and get these pieces in the beds as quickly as possible.

Lay wax paper on the top and bottom of the core so that you protect the beds from the gorilla glue.

press the core halves together and make sure they are tight.

put the top bed over the cores and press the core from both ends to ensure that you are making a tight joint.

apply pressure with a long piece of wood over the top of the cores and weight it down . . make sure you have nice even pressure over the joint. I like to put something like a sheet of ply over the cores to spread the load . . you want to make sure that area where the joint is is compressed so that the glue will not foam out!

Do the same with the other wing half then place the cores and beds over the top of the first half and compress the whole thing for 6 hrs. - at least ( I let mine sit over night)

Make sure you have the cores centered in the beds and press the core from the root and tip to ensure that there is a proper seat at the joint!

Watch for any glue that oozes out and remove it before it has a chance to harden.
Jun 27, 2010, 11:34 AM
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pval3's Avatar
take the cores out of the beds after they have had at least 6 hrs - time to dry and using a hobby knife, gently cut flat against the surface to remove any foam that oozes out of the joint. you want to make sure that this joint is good all the way around so that there is no gaps in the surfaces. If there is an area that has pulled slightly, add a litte gorilla glue and let it sit, then cut flush cut whatever oozes above the surface. The better the joint the better chance you will have a a strong wing.
Jun 27, 2010, 11:34 AM
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pval3's Avatar
lightly sand the core halves to remove any extra flash and check to ensure they are straight.
Jun 27, 2010, 11:37 AM
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pval3's Avatar
take the cores and set them back into the beds.

Take some hot glue, place the left and right halves together and check the fit beteween the L and R sides . . make sure that the beds line up with no step between the L and R sides. If there is, shim the L or R side to bring them level.
Remember that you MUST do this for the root, center break and tip.
If you do not, the joint will cause a dihedral or anhedral depending on the error!
Jun 27, 2010, 11:41 AM
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pval3's Avatar
place a piece of masking tape on the leading edge of the two core beds top and bottom. This will allow you a guide to ensure that they line up when you connect them front to back.
take the hot glue gun and run a thin bead around the perimeter of the bottom core bed then pivot the L & R core beds together to give you one 60" core bottom.
With the core still in the bed, do the same for the top.

I like the hot glue because it really sticks well and fast PLUS if I really screw up, I can always loosen it and fix my errors . . although it is really tough to get off!

Now you have a chance at a completely straight wing.
Jun 27, 2010, 11:54 AM
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pval3's Avatar
Using a 3000 4s pack, I was able to move the servos, motor around with the spars and get it to balance at 7.8" from the nose.

I will need to add a little lead but it worked with a little finagling.

I played with the dual packs again but the weight added was greater than I was willing to work to bring the CG back aft. It caused me to push the motor further back than I was willing to do with this torque a motor.

For an inrunner set up, it probably would work but the mount I found gives me the latitude I wanted with this motor from the start.
Jun 27, 2010, 11:57 AM
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pval3's Avatar
The elevons are going to be cut from the cores.
They are 2" deep and run the length of the outer panel.
The servos will sit primarily in the innter panel but the arm will extend through the joint and into the outer panel.
This gives a nice straight control arm with maximum meat to mount while keeping the tips nice a light for faster roll response. It also means shorter servo wires and that can serve nothing but a positive in so far as prevention of interference.
Jun 27, 2010, 12:02 PM
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pval3's Avatar
After much research in this blog and rc U, it looks like the conventional wisdom wins. elevons will be cut from the top meaning that the hinge line will be on the bottom of the wing, however the control arms still be mounted on the top.
Jul 15, 2010, 01:00 PM
chronic in training
grfcon's Avatar

any updates on this one phil?

inquiring minds want to

how close are you to covering and maiden?

I know it is summer and time to get to the corolla house for you
Jul 15, 2010, 11:09 PM
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pval3's Avatar
Ahhhhh Grfcon .. . .. .. .as my older daughter says - if wishes were fishes!@

I am in long term training in Dallas and will be out of the model building loop for the next four weeks at least.

Before I left I did a lot of the busy work getting all the pieces "fit" and placed but most of the time was centered around mounting the motor and cutting the elevons just right.

My original mounting plate idea ended up being too deep and too far forward cutting into the battery area. The motor and mount fit, my plate was just too big and didnt have time to recut and mess with.

I got twisted around the axle on this part as I am trying to give myself as much space for the spars to keep things straight and strong.

I am on my way to being able to answer just about anything about the CRJ700 . . . give me a few more weeks and I should be ready to rule the world from 410!

For now I need to hunker down and study my 28 pages of limitations, systems, ops manual and company manual and FARs so I dont fail my oral and type ride in three weeks!


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