BlackPhantomDragon

I went to buy a 120 space walker last Saturday and come home with Seagulls new PT-19 2M span. They had just sold their last Space Walker and they convinced me with very little persuasion that this was the ARF to get. Always liked the PT-19, especially the Blue and Yellow.

BlackPhantomDragon

Here is a couple of pics of the box.
It also has working sprung Main Struts and also working sprung tail wheel.

AA5BY

The PT-19 looks great... I'm interested but will explore more in a separate thread.

bgee

Coded Language, I like your tank setup. I have just finished installing a dle 30 in my spacewalker. Just waiting for our strip to dry out so I can fly it. The hardest part was getting the tank to fit for the dle. I have used a j tec custom made pitts muffler so I don't have to cut the side of the cowl.

Brendan

codedlanguage

bgee,

The tank is placed on an "H" made of scrap pieces of balsa and/or ply. It may be hard to get to the LE plastic screws, but it makes sense to place the tank as close as posible to the CG. That's why i've shortened the front plastic screws with maybe 1 cm (aprox 0,5 inch).
I was looking also to use a pitts style mufler but mine was touching the bottom edge of the firewall.

George

outlander

Dan4466

I have just ordered a Seagull Spacewalker II 120 and would rather use the DLE 20 than the DLE 30 .
Have you flown your Spacewalker with a DLE 20 yet ? Anyone else tried the DLE 20 in this ARF ?

bgee

I first tried a standard pitts muffler from dle australia and for it to fit would have taken a fair bit of modification. I have used the one designed for the aeroworks cessna 195 and it fits perfectly.

rowdyjoe

My Feedback: (9)

Does your 30cc have a side mount or rear mount carb? It's difficult to see in the picture. Very nice looking exhaust and a great solution.
I have a Turnigy 30cc on the way with a side mount carb. I'm wondering how well it will fit the cowl. I also have a 26cc engine on the way and am still debating which engine to install.

bgee

My DLE 30 has the rear mounted carb. A side mounted carb would probably mean you would have cut the side of the cowl.

Brendan

rowdyjoe

My Feedback: (9)

Hi folks. I'm new to the thread and new to fuel engines in general. My first attempt was a 68" WS Escapade with a 20cc gasser mounted. It has plenty of power but, won't stay running once airborne. Can't figure that one out and the multiple dead-stick landings have taken their toll on the fuselage so, I need a new one.
In the meantime, I'm building my Spacewalker II 120 and have just completed mounting the GRpro 26cc engine. I managed to use the included "nylon" engine mount by fabricating brackets to mount the engine. I first thought that big cowl would surround the entire engine but, I'll have to cut some holes to get air to the cylinder head and make room for the pitts style exhaust.
The recommended prop for this engine is an 18X8 but, I think a 17X10 would perform as well and provide the same load on the engine. I'll start with the 18X8 but, may try a 17X10 at some point just to make it look more scale.This is my first Seagull ARF and I'm very impressed with the quality and comprehensive parts inventory. I don't think they've left anything out that's needed.
Here's a few pix of the engine mounting. Still have a way to go to complete the installation.

RJ

rowdyjoe

My Feedback: (9)

I sent the engine with the side mounted carb back to HK USA. It was too large for the plane and would have created major mods to fit.

RJ

codedlanguage

Great idea on installing the gas engine using the provided mounts instead of metal stand off's.

BlackPhantomDragon

Hi RJ
Interesting set up on the engine. But I would be concerned with this set up. The screws don't look high tensile and would be much better if socket head bolts were used with nylock nuts. I would say around 4mm dia, Also the metal brackets don't look strong enough to take the vibration of the motor. I would be concerned that either those screws would come loose from vibration if they did not break first or that the metal bracket would crack and break.

It would be much better to use stand offs for the motor and remove the engine mounts. This would be a lot safer and would perform better.
If you wanted to use the standard mounts I would suggest a DLE20 beam mount engine. Would have more power than the 26 and bolt straight in to the standard mounts and you would not need to remove as much cowling.

I don't mean to rain on your idea but I don't believe it is a safe or long term solution for the engine or plane.
May be someone else can comment on the set up.
May be if you post in the gas engine forum where they use them all the time and see if they have any other suggestions on your idea or weather it could be improved.

I agree the seagull ARF's are great quality, I just bought the PT-19. Still would like a spacewalker as well.

All the best in your endeavors.
Regards Greg

rowdyjoe

My Feedback: (9)

BlackPhantomDragon,

I had those concerns too but, decided to try it anyway. Each no. 5 bolt has a washer and lock washer and is short which should reduce the concern for cracking/breaking. The material is not high tensile but, is short enough to resist breaking and should flex a tiny bit rather than break. Additionally, since the mount is nylon/plastic, I expect it to absorb some of the vibration and I intend to run well balanced props to reduce/eliminate any additional vibration. Frequent inspections will reveal any potential problems.
The problem I faced with standoffs is bolt length. I have not been able to find no. 5 bolts long enough for the standoffs. Standoffs must be 3" and they are available via the net but, the 3.5" bolts are not available locally and did not come with the engine. I can substitute 10X24 or 10X32 standard hardware but, can't find it locally in high tensile. I've checked all of the large and small hardware stores and they don't have them. Even if I found them, I'd be concerned about those long bolts breaking.

Time will tell if my system works or not.

Thanks for your concern and advice.

RJ

BlackPhantomDragon

Hi RJ
You could use something like this http://www.dlenginesaustralia.com/dl...&productId=293 the bolts are only short and screw in to each end of the standoff.

May be you could tap your holes to suit some bolts.

Good luck.

Regards Greg

rowdyjoe

My Feedback: (9)

Greg,
Thanks for the suggestion on the standoffs. If DL sells them therre they should also sell them here. I may give them a try.

Garry

bikerbc

I have a DLE 20 in my walker and it fits well and has great power..I am having lots of fun with it...It does shake a few things loose though so you gotta keep a look out for things comming loose..The hatch glue joints a such...The little DLE 20 has lots of power and pulls it around fine . The Walker is sure a nice flying plane. It likes to float so it lands pretty slow.. The DLE 20 is a bit noisy..Mine puts out 93 decibals and we have a 94 limit at our field so I made a little Stinger out of a plumbing fitting to defuse the sound a bit and it brought it down 3 decibals without a noticable loss in power...

Pete Bergstrom

I agree with a couple of the posts here. the Seagull mounts can get a little soft when heated up (this shouldn't be an issue with your installation) but Ithink you are asking a lot of them. You could go 'old school' and actually build the standoff's out of plywood. This is a picture of a standoff I had to make for a Seagull AT-6 when I was putting in a 7 cylinder radial. It took me about one hour to make and epoxy overnight to the firewall. I made from 1/4" plywood and you don't have to worry about torsional twist that you get from 3" long standoff's.

The 2nd picture is just a teaser to show you what the engine looks like in the cowl.

Have fun!

Pete

Pete

rowdyjoe

My Feedback: (9)

Pete,
What's "old school" to you is new school to me. I've only been in RC for about 3 yrs and this is my first attempt at fuel aircraft of any type. The plywood box mount picture you provided looks very sturdy and simple. Thank you very much for the idea. I think I'll give it a try.
By the way, the photo of the radial mounted is great. You goal has been achieved as I'm drooling already.

Garry

Kostas1

Pete,

have you flown your AT-6;

BlackPhantomDragon

Hey Pete
That radial looks great in the cowl, Should haul it around well.

Have U run it yet? Are U going for a scale exhaust out the side with it. Would be ideal to ad that extra scale touch.

Regards Greg

Pete Bergstrom

Garry,

You are right about your 'old school - new school' comment. I apologize if I came across the wrong way. It is an easy way to move the engine mount any where you need to based on your engine of choice. A couple of things to watch for when your are planning this:

1. Make sure your transfer accurately the center of the thrustline from the original firewall to the new 'standoff' firewall. You can determine the centerline of the engine by transferring the mounting position of the original engine from the mounting pads of the included engine mount to the firewall. Then draw a line diagonally between the existing mounting bolt locations. where that intersects is the centerline of the existing mount. Lastly draw a line perpendicular to the first line (the mounting pad line) that goes through the intersction of the two diagonal lines. This will give you the designers intended centerline for the engine mounting.

2. There should already be the correct right thrust angle built into the firewall which allows you to make the plywood standoff box square.

3. Draw onto the standoff box the centerlines you will use for mounting your engine on both the front and rear surfaces with connecting lines going up the sides. This will make it easy for you to accurately mount the standoff correctly on the original firewall.

4. You can either glue the plywood standoff in place as I have or bolt it in place onto the exisiting firewall. I chose to glue it to avoid worrying about the standoff to firewall bolts coming loose and having to check them periodically. Less fasteners means less chance something will come loose.

About the AT-6 ... yes, I have flown it all summer, to include a Fun Scale contest in Ohio where together we did really well. I have mounted a collector ring on the engine so it exhausts in a scale like location (about 8 o'clock when viewed from the front). I'll add a photo of the engine with the collector ring here and I'll start a thread on my entire mounting process elsewhere so I don't hijack this thread. When I get that upand going I'll make a post here.

Have fun with your spacewalker - it's an awesome flying airplane and you'll have a blast with it.

Pete

rowdyjoe

My Feedback: (9)

Pete,
No offense taken and I hope my reply didn't indicate that there was. I was trying to indicate how little experience I have when it comes to fuel planes. Lord knows I've repaired enough foamy types to have learned a few things about them but, not much of that is transferable to wood and covering. I have the tools (I think) but, the knowledge and experience is lacking and I certainly appreciate your advice and instruction.
I'll certainly follow your advice on the "box" but, 1/4" ply seems a bit heavy to me. Do you think it needs to be that thick? To save weight, do you think 1/8" ply would be strong enough to secure the 26cc engine to the firewall?

Garry

Pete Bergstrom

Consider this ... the last 26cc weedwacker you used most likely had an aluminum or magnesium shroud the engine mounted to and then two places for your hands to hold the unit, it its only turning a very lightweight string at the end, not a 16-18" propeller. There are a lot of forces at work here and a solid firewall/fuselage/engine mount connection will go a long way towards adding life to your airplane.

One of the most important connections in your airplane is the engine to the fuselage mounting. Engines run much better with a solid mount under/behind them so this is one of the last places I would skimp. The blinds nuts you'll use for attaching the engine to the new firewall will be almost 1/4" deep so instead of having to double up plywood in the area of the blind nuts I suggest you use the 1/4" material for the firewall. The rest of the box can be made from 1/8" ply but I would only use 5 ply, not lite-ply for this job and use plenty of gussets (triangle stock) in the corners. There is not a lot of gluing surface when edge gluing 1/8 ply to itself. The total weight of your box will be about the same as the aluminum standoff's with a 3" steel bolt through them when its all said and done, and you'll end up with a rock solid mount for your engine.

Pete

rowdyjoe

My Feedback: (9)

Makes perfect sense Pete. Thanks again. I'm going with 1/4" ply.

Garry