Seagull Boomerang Trainner ARTF

[Alex Hasell]

Hi Ron,

First of all Hello and welcome aboard, Good to here from you and would be interested to hear how you get on let me know how you progress hey?. I found what you said to be very interesting and relevant to my current situation. You have highlighted a couple of points about the Boomer perfectly there as i have the same experiences and feelings about the model to, well except the spinner afraid i'm with Shaun on that one although i do agree the Ally would look cool!!

Can i ask how you are getting on with the new wheels this is my urgent need to do item as i have same problem?

The engine mounting is a very good point at present mine is in with the self tappers although im not happy and will be changing that to at the weekend before she takes flight.

I found that they start pefectl by hand and i like to feel what im doing as well. The C of G hows that now i have been thinking that that stated in the book are some what off espescially as you say with no fuel she is a nose heavy bird isn't she! where does your ballance point come out at with the RX bat in the position you have stated compared to the 7.5 to 8.5 cm from leading wing edge could you tell me the distancenow if at all possible thanks!!

How does she fly? anyway got to go good luck to you and hope to hear from you soon.

Regards, Alexx

[Gaz Elliott]

I have a boomer . She is 18months old and has  a few battle scars to say the least. After a cart wheel ( forgot to change tx to different model servos were reversed ooops!) I decided rather than patch up to recover in black and red. I put on larger wheels ( our patch can get a bit long , Changed to tail dragger getting rid of the trike u/c as i got sick of the nose wheel bending. Finally completely over powered it with an mds 60 ( not problems with engine  picked up for a bargin in an auction) don't use all the power but nice to throttle away some times. tend to keep about 1/3 to 1/2 power though still finding feet. Slow learner!!! Since tail dragging not had any where near as many problems with u/c on landings . got an excel 2000 tainer and that is also converted to tail infact my whole fleet tail drag. Waco bipe, super chipmunk and the 2 trainers. Look flying the trainers as they have taught me so much along with my buddy lead ( Will save you a fortune)

Good luck

Gaz 

[Kelly]

Regards the CoG it is always preferable to be slightly nose heavy rather than tail heavy.

Always balance with the tank empty.

What balancer are you using Alex?

[winchweight]

Alex, just pick some larger wheels off the shelf and crack on. IIRC I used 3 inch wheels on my old trainer and they were fine. I would go for rubber tyred wheels though as you will quickly eat foam ones until your landings are perfected (and still probably then if I'm honest).

[Alex Hasell]

Oh it,s been so hetic at home this week just havent been able to keesp up with the blog so i will make the best efforts to get it finished

So last time id fitted the tail section to the model which i'm pleased to report is still nice a square which is amazing for me. Next up then a nice simple bit the fuel tank bit of a non brainer this following the book position of the "bung" is one pipe top two pipes at the bottom bend the top pipe to face the top of the tank this will be the pressure feed from the exhaust. Bend both of the other tubes down one with a length of pipe with the supplied clunk  filter attached this should end near but not touching the back of the tank ( DO NOT follow the measurements in the book they are WRONG) and the other to follow suit but with no clunk (i fitted a small nonfilter clunk just to aid in drainig the tank).

Once this is done insert into thetank ensure its pushed all the way in!! and tighten the retaing screw in order to expand the bung in the tank neck just be carefull not to over tighten this as it will split the tank if its to tight.

Insert the completed tank into the fuselage give it a wiggle to make sure it goes in properly the bung should be clearly visable through the bulk head . I think the design has been moded as some one mentioned extra padding to prevent the tank turning due to vibration but the airframe actually "embraces" the shape of the tank you will see in the pics anyway. Now in one of my previous pics looking into the fuselage you will notice a piece of ply attached to servo tray via a elastic band after some head scratching and searching the book for the purpose of this piece of wood (theres no mention of it anywhere) it dawned on me that it actually fits behind the tank to stop it moving forward or back during flight Doh

[Alex Hasell]

PIC showing the inside "former" which i belive is a later mod (not in the book) to prevent the tank twisting a good idea i think.

Please excuse me i forgot to take a pic with filter attached to other line also note different colour tubes belive me its a good idea!! 

Orientation of completed fuel tank

[Alex Hasell]

Showing the fitted tank note only small amount of padding under rear of tank just to offer some support and the misterious piece of ply in situ holding the tank firm this was put in using a touch of cayno.

Thats it for the tank next up servo installation and push rods.

[Former Member]

[This posting has been removed]

[Alex Hasell]

Eric,

Yes it's a very valid point Eric, something that is on the "list to improve" that since starting with the model i have acumelated because i was also hoping the tank tubes would me metal rather than plastic But this is the hardware that came in the box and at present it was not an item that i  have any of due to my newness, lack of time involed wth rc i prefer!  I haven't yet got a spare's  bin that i can raid when needed But sure that will change.

Anyway it concerned me two so what i did was to slide a length on wire throughthe pressure feed tube of a smaller but very close diameter to the tube. Using a variable temp heat gun i heatthe plastic very carefully before bending to the desired angle once soft enough and held it in position till it cooled and re-hardend. The wire preventing the tube from colapseing on its self the wire is  obviously removed. So far it has been ok and no problems with filling or shrotend run  times and i forsee it been adequate untill a metal replacement is sourced.

Espescially with the weather as it is lol    Eric i have also brought a sim that you previously recomended rc planemaster £20 good stuff

Regards, Alex.

[Kelly]

I must have the older kit, mine does not have the new former for the fuel tank . The fuel tank still has metal pipes.

I wonder if the U/C is now a bit stronger?

It looks like Seagull have  been taking on board comments / reviews  from Boomer owners.

Good idea the sim. I have one and did a few hours stick time on it before flying my Spit, glad I did ,was very rusty after my 30year sabbatical from R/C flying. 

 Your Boomer is looking good Alex .

[Alex Hasell]

Kelvin,

Yep shes come along nicely i'm really pleased with her, I thought that after your comment about tank rotation, it's as David states in this months mag of the Sparrow Hawk Seagull have quitely been improving there quality over the last few years which can only be a good thing

Not sure why they have gone from metal to plastic on the tank fittings though a bit of a puzzle!

The U/C well i don't know to be honest there is quite a decent ply former inside the airframe to which to screw the bracets to this might or might not be an addition? but i have also found it to be pretty weak to be honest bends far to easyily as well i found the wheel collects virtually useless as they work lose easily which will me taxi in a straight line is impossible so that why i am fiiting larger wheels and washers either side of wheels to try and keep things a bit more straight and true! eventually i plan to totally retro fit a much firmer U/C alltogether.

Yeah have done good on the sim i think it will really help when i get to actually fly i feel that my thumbs have "learn't" if you follow and besides what else can i do the weather has been terrible here for well overa week now all i want to do is go flying AAAArrrrhhhhh!!!

Regards, Alex

[Kelly]

Hi Alex.

To help hold the wheels on, try to make a flat spot on the axle with a file or dremel  at the point where the collet  grub screw makes contact, it gives it a better grip,also use a bit of thread lock on the grub screws.

Yes this weather ifs a bit bad not flown myself since last thursday .

Kelvin

[Alex Hasell]

Ahh good idea there thanks mate, didnt think of that one i'm off to do it now cheers.

[Alex Hasell]

Next we need to fit the servos it simple to do just ensure you drill the pilots not to big but they are a god idea just to help not split the wood i have used 2 DS821 digis from spektrum and 2x futaba 3003's

DS821 for Elevator and Ailerons

3003 for Rudder and Throttle

Next you will need to fit the control horns, one on the rudder and one on the elevator again this is quite a simple operation position the control horn and when satisfied mark its position and the two mounting holes i find with anything like this it helps to draw around the horn to so you can be sure it lines up properly when it comes to bolting them on. Drill two holes as marked with a 2mm drill bit be sure to drill straight!! Wnen you have done that its time to fit the horns i put a drop of cayno on the bottom of the horn and also on the back plate just for an added bit of security  then tighten the nuts clamping the horn onto the control surface.

                                        

The control horn fittede to the Elevator now on the reverse side you will be left with alot of tread from the bolts pertruding passed the locking nut using a pair of snips cut this thread off flush with the nut then file it until the thread and the face of the nut become one serface i have seen these bolts just cut off but if you file them it will act as a thread lock given theres only a few turns on the nuts in the first place i highly recomend you do this just to be sure they wont come loose also a dot of cayno onto the finished article. Hey theres no such thing as overkill when it comes to linkages and control surfaces if you ask me!

[Kelly]

Yep nothing like the old "belt and braces" approach to make sure nothing falls off .

[Alex Hasell]

Ok so you have done the last step as per the instrucions... Good ,you have conected all the clevis's mid point to start with on the control horns checked the rudder for movement and its ok check the up Elevator thats ok down Elevator oh dear...... If like me your sat there looking puzzled or think your seeing things be asured your not the down elevator movment is hampered by the rear end of the fuselage!!! Great, well theres no mention of that in the book is there!!!  It does however show you how to CORRECTLY fit the control horns  holes of the horns over the centre line of the hinge- this is the mechanically best position to fit the horns ok so dont be tempted after reading this to fit them further back along the elevator insted i would advise do what i did and cut a small channel out of the fuslage to give the horn the clearance it needs see the pics for clearer detail

[Alex Hasell]

soory its a bit out of focus but you can see what i meah the channel marked on the fuselage needs removing  in order to give enough clearance for the control horn without moving this the maximum movement of the elevator in only 6mm!!!!!

[Alex Hasell]

Next i fitted my radio gear i am using Spektrum 2.4gig stuff and have fitted accordiningly i don't think theres much to say on this part of the build as how you fit it is a personal choice and also dependent on what gear your using. All i would say is use plenty of padding for your reciver and one tip i got from another builder is if fitting a switch into your plane remember the exhaust from the engine is on the right hand side viewed from the rear so put your switch on the left that way it won't get gommed up with oil from the exhaust when its running.

And after ihad a little tidy up the finished radio installation looks like this.

[Alex Hasell]

Ok i had nearly finished the build by this stage next i fitted the engine again this is qute a straight forward process first of all i made sure the screws holding the engine mount were tight, good job as well as they all needed half a turn!!! so beware i would of prefered captive nuts and bolts but this is an area i will watch closley and if need be can change it at a later date. Just for peace of mind i backed the screws off one at a time to ensure the mount didn't move i didn't want to disturb the angles that are pre set on the mount and applyed a little cayno to the threads before retighting them.

Next i dry fitted the engine to the mount checking the recomended mounting positon which is 110mm from the fire wall to the back plate on the prop shaft i found it easier to make a template from stiff card 110mm long rather than continuosly checking with a ruler. Once i was happy i marked the mount hole centres with a nail and as with the controll horns scored around the mounts as well. Remove the engine and use a 2mm drill bit to make the holes the book says 2.5mm but i prefer the 2mm as it just gives the screws a bit more material to "bite" into. Of course some 3mm bolts and lock nuts is a better option if you have these availiable i didn't but as soon as i can i plan to change them over having said that so far the screws have proved to be up to the job but i would still use bolts if possible.

Once i had fitted the engine i connected all the fuel and pressure lines to the various niples. one thing i would say is the book will tell you to remove the throttle arm from the carb to connect the push rod but instead i left it on and simply pulled hte rod out a bit connecting it to the arm then slid the engine back into place on the mounts i thought this better than disturbing any thing.

Something very strange and unwanted happedto me next i was connecting the fuel lines and came to connect the short length between the rear needle valve and the carb when i noticed the nipple on the needle was loose so i gave it a turn with my fingers, to my surprise it came clean off in my hand leaving the thread inside the body of the needle valve!!!!  saying to my self thats not right i sat like a dummy staring in disbelief that my brand new engine ad just broken a part before its turned one rev under its own power bummer!! Anyway after some frantic phone calls i managed to track one down at Whitchurch Models so the next day i had the replacement fitted and was back on track. Both myself and the chap in the shop were amazed at how this hadbroken and i am convienced that it was down to either a material  weakness as it had sheared off or the component had been machined wrong leaving the wall thickness dangerously thin i am glad it happened really as if it was as easy to break as it was better it happen on the bench than on her maiden flight! I have reported the problem to SC and they were extremely apologetic and are looking into it i am awaiting there reply now so ill get back to you and let you all know what they say. 

[Alex Hasell]

The boxed SC46 good stuff

Here it is fitted in model 110mm from the firewall starting to get exited by this point!

[Alex Hasell]

Here you can see the replace fuel nipple! note the broken one next to the valve the thread was left inside the needle valve body which was handy! luckily i have experience in removing this type of things so it was to much of a head ache.

[Alex Hasell]

[PeeGee]

Are you happy with the pushrod to servo fittings?  I 'm concerned  they may loosen due to vibration and/or fuel residue, as can be the case with wheel collets.  If it's necessary to use threadlock adhesive, praps its better to replace these at the start?  

[jimmyboy]

 

   Hi, all you Boomerang afficiondos, has any one electrified this model, I got one as a present but I would like to go the electric way.

All comments or suggestions would be gratefully received.

Jim.

[Tim Mackey]

It wont be cheap, so first I suggest you indicate how much YOU are prepared to spend on the conversion, and then we will see if it is feasible, before going into too much detail here.