Mark... I'm just hitching to try building with the foam method. Its my first using this stuff. Except for the actual design of the Euro I have only about 3 hrs time taken to get to this stage. That includes printing out and making up the stations... 1 hr Then setting up the plan form on the table ready to go as shown in my last pics which took all of maybe 2 hrs. I'm going to glass with two layers of epoxy and 6oz 45 deg weave cloth. Wing saddle an extra layer. If still reasonably light I'll do a final layer of fine 2oz cloth so that I'll need less surface finish thus keeping weight down. So basically should end up around 14 oz in three separate layers with foam formers inside.

I'm now starting to think of running my JetFan 90's on 8S instead of 6S. That should give me around 3 kg of thrust per side using independent power plants.

I'm getting that way too!. It was odd how I found out about MPF. I was looking for a good way to take off the plastic from FFF, and ran across their thread in the foamy scratch build forum. Great recommendations from all who had used it. Got mine pretty quick, ordered on a late Mon night 11th, deliverd by noon Thur. 14th.

Just finished hot wiring some blue foam for intakes and nose. Now to clean off the building table! Always nice to start out organized, to bad it doesn't last.
I wanted to have most verything on hand, foam, 1/8th 6-ply for formers, servos, etc before I started, now I do and have no excuse not to get on the stick! I hope to start my build sometime tomorrow. Should be a good day for it, they are calling for 4"-8" of heavy wet snow with freezing rain, any time after midnight thru early Sun A.M.

Assuming, mine turns out as I hope, I intend on glassing it too. Got all my cloth and other goodies this past Wed.. Mine being smaller, I think I can get by with 2 layers of 4oz. There will be plenty of stuctural support from the 6-ply formers. Also going to try using white pigment in the epoxy, should make it easier to paint later on.

As mine will be a single JetFan, going with the Het 1200Kv 12s, more than enough power. Shooting for an AUW of between 10-11lb.

Looking forward to your build.

'I'm going to glass with two layers of epoxy and 6oz 45 deg weave cloth. Wing saddle an extra layer. If still reasonably light I'll do a final layer of fine 2oz cloth so that I'll need less surface finish thus keeping weight down. So basically should end up around 14 oz in three separate layers with foam formers inside."

To me that seems like a lot of glass/epoxy over foam. Sure 14oz layup is necessary? I used fanfold on my 1/4 scale Me-163 and only gave it one layer of 3 oz cloth. Just saying........

J

But John.... You have more guts than I do... The foam weighs very little and I will be abusing this thing with aggressive aerobatic displays. I'll be carrying around 5lbs of power plant, rugged landing gear and a lot of test avionics prior to making the molds. So I need a tough airframe. I will test it after the first layer of 6oz and if I feel comfy will just add the 2oz for finishing a forego the second 6oz.

I don't know if this would be of any help, but in humbertomelo's build of the Super Habu - 120mm EDF - Parkjetdesign, I had asked him about the weight the glass added. Sizable plane at: Length -72.8" WS-59"

http://www.rcgroups.com/forums/showp...6&postcount=73
If my conversion is any where close, the glass was just over 3 oz sqyd.

You know your build bette than I Ace. I'm sure when you get to that stage that the model will "talk" to you and you'll know what it needs. Good luck and let's see some pics soon!

J

Laugh... You are so right. Well, its talking to me at this moment saying its a pain in the butt... A little more involved than I thought getting these panels to fit.

There is a learning curve.

J

Originally Posted by J Morgan

There is a learning curve.

J

Hey John....Truer words never spoken. What I thought was going to be an easy build is not so. When you just look at the stations it looks like a straight layup. However, once you start laying panels you realize that everyone is just about a compound curve so takes a lot of finessing.

Biggest mistake so far was to install all the stations on the alignment board with out adding the doublers on each station. If I had done the doublers first it would have taken maybe 45 minutes when laying flat on a cutting mat. Installing them afterwards like I did takes forever...ouch!. That was lesson one....

It does take a learning curve. Being the first time working with a foam panel build it took a few screwed up panels to learn how best to pre-curve then get the compound into it. I have now developed a technique that allows much faster and more accurate panel cutting and installation. Lesson two...

I must say though that working with these new foam panels is very enjoyable. Using my new foam glue gun I am able to have some working time to get things lined up then tape or pin into position. Thirty seconds later I'm on to the next.

I did not get has much done today as planned. I forgot that I had a club meeting to attend and also had a visitor. Big surprise was my new 90mm Fanjets arrived and they look gorgeous. I think that I'll be following the path that John Morgan suggested regards the weight of glass cloth for the finish. With a few panels in place this thing is getting stiff and very strong. So maybe get away with a couple of layers of 2 oz cloth.

Tomorrow is fly my Flanker day so not much will be done.

Coming along nicely ace . Looks like you catching onto this foam thing nicely . You'll be surprised how strong the structure is once built .

JIM!!

Glad to see the jet is coming together.

I have a slew of Google Sketchup designs I've been working on between trips I'd like to build. I have been busy as a bee but there will be time for some collaboration and flying at the field soon I hope!!

Eddie P

Originally Posted by acesimmer

Thanks guys.... Just emailed Mike he seems to be back ordered. Also found two errors in the motor selection table for 6S so not feeling good about trusting the published info...

Originally Posted by acesimmer

Where do you buy the jetfan 90? Is it pre-balanced Can I purchase with the motors mounted and dynamically balanced. Only found one source and they only have the fan with no motor and only one in stock.

Jim the Jetfan90's are the fans that Brad and I have in our F-86's. Pretty quiet, great partial power performance and sound too, full power is great. Balanced 95 percent out of the box, 99 percent with a little care installing the spinner cones assuming you are using a quality motor. All bets off for cheap motors as they tend to not be well balanced in my experience.

To get better you have to spend a lot more. I've purchased direct from the maker in Austria but it took a while and also from Mike here int he USA. I've owned 3 of them, 90MM and 80MM. Mike, if he has them in stock, ships out very quickly but you will pay a slight bit extra.

Hi Eddie.... Im looking forward to you flying at our field. I got my fans and they look great. I will be buying quality motors, ESC's etc. I'll wait until I get it glassed and get an idea of weight then decide the battery options. Looking more like maybe 8S. Jim Logan has two new turbine models one being a ten foot F-18!! You may end up being his test pilot.

I found a problem..... As in the pic you can see the canopy section is in place. However, something did not look right. So this morning I have gone over everything to check all the measurements out. What I have found is that station U which is around mid canopy did not print to scale? It is 6mm shy all around the perimeter. This caused the canopy to indent a little in this area and that was the clue. So rather than remove that station and basically start all over I found that adding a strip of the 6mm foam to the perimeter gets it back to the correct scale and outline. I'll then simply add a thin sheet of foam to the indent or lay on some spackling filler and sand to correct shape dependent on what it looks like when I have the sides done. So today I'll take a break and go fly as the weather is sunny and calm.

It's looking good Ace. I think you will find that once skinned it is very strong and light. The skin carries the loads. I normally cut out most of the bulkheads as I go along skinning. My F-16 has most of the formers/bulkheads cut out.
I should have mentioned the bulkhead strips, I call them nailers, a carpenter's term.
Have a good time flying.

J