| Welcome to Just Fly It. We hope you enjoy your visit. You're currently viewing our forum as a guest. This means you are limited to certain areas of the board and there are some features you can't use. If you join our community, you'll be able to access member-only sections, and use many member-only features such as customizing your profile, sending personal messages, and voting in polls. Registration is simple, fast, and completely free. Join our community! If you're already a member please log in to your account to access all of our features: |
- Pages:
- 1
- 2
| Brodak United Build | |
|---|---|
| Tweet Topic Started: Saturday Feb 23 2013, 11:30 PM (2,928 Views) | |
| Tony Leong | Saturday Feb 23 2013, 11:30 PM Post #1 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
I've been waiting to start building this plane for some time but had to put it off because an essential accessory was not available. This plane requires a propellor shaft extension which extends the prop shaft by 1/2 inch. Just last week, it came back in stock at Brodak's so I ordered it and its on its merry way to me. So, no more excuses for not starting on the build especially now that the BMJR profile Nobler is completed and ready for her flight trials.![]() Opening the compact box revealed a well packed box of laser cut balsa, ply and accessories. After a quick look, the balsa sheets and blocks appear to be of good quality being crisp, light and with consistent grain. Hardwood and hardware are grouped and bagged. The hardware provided with the kit is very complete and almost everything needed to complete this model is included. A Brodak adjustable leadout guide package (BH-760) and weight box package are also included. Parts that need to be purchased - tank, wheels, 1/2 inch Fox prop shaft extension. ![]() The kit also comes with rolled plans and a very detailed instruction booklet. I shall spend the next few days perusing the manual in preparation for the build. The instruction booklet is very detailed with many photos illustrating the construction process. Specs for the United are shown in the photo below. ![]() I shall be using an Enya SS45 S-PL Pro (Ring) to haul this plane around. Its spanking new being fresh out of the box and will require running in. ![]() The construction manual shall be my bedtime reading for the next few days. Edited by Tony Leong, Saturday Feb 23 2013, 11:58 PM.
|
![]() |
|
| Tony Leong | Tuesday Mar 5 2013, 10:12 PM Post #2 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
The quality of the wood included with the kit is quite impressive. Having selected the wood for the wing build, I can see that the wood grade provided was appropriate for the intended purpose ie. spars were firm, very light balsa cowling blocks etc. I didn't have to replace any of the wood provided for the wing.![]() ![]() Hardware supplied with the kit is quite comprehensive. Dubro hinges instead of CA hinges. Landing gear, blind nuts, pushrods, flap and elevator horns, bellcrank, leadout wire kit and keepers and even a weight box kit (but no weights) are included. Pretty complete. Just needs wheels, a tank, power plant, spinner, covering materials, and glues to complete. Wished that wheel collets and an adjustable lead out kit could have been included as well but alas - no. (Post note: the kit does include an adjustable lead out kit. It was buried amongst a bag full of hardware parts) ![]() The build starts with the cutting and pasting together of drawings for the wing panels. Unfortunately, I botched up the photocopying of the plans today at the the photo copy shop and now I have two port wing panels but no starboard wing panel ........doh!
Edited by Tony Leong, Saturday Mar 9 2013, 12:59 PM.
|
![]() |
|
| Tony Leong | Friday Mar 8 2013, 10:28 PM Post #3 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
I'm starting with the wing construction. The leading edge is a T-bar that is made out of balsa sticks. I found two of the four balsa sticks provided to be undersized, being 3/8x3/16 in instead of 1/4 in. Nothing a bit of work with my trusty balsa stripper won't cure but still, its an annoyance. (Post note: as it turns out, it wasn't that the balsa sticks were undersized. I had actually used by mistake the balsa stick meant for the trailing edge cap. This meant that two 3/8x1/4 sticks for the leading edge was missing in my kit.)![]() Edited by Tony Leong, Tuesday Mar 12 2013, 10:28 PM.
|
![]() |
|
| Tony Leong | Saturday Mar 9 2013, 03:25 AM Post #4 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
The kit actually does include a Brodak adjustable lead out guide. I've not used one before. Following the instructions and the drawings on the plans, the adjustable lead out is to be glued to the last rib. I've not used one before and the instructions in the building manual and the small leaflet included with the lead out guide is somewhat skimpy. It appears that the lines are supposed to exit through the two holes provided on the plastic bit that slides within the ply strip. It appears to me that there is a possibility that the lines may end up abrading/cutting into the plastic over time. The plastic looks like the kind that epoxy won't stick on so there is little point in enlarging the holes and inserting brass tubing. Or should I just replace the plastic with a ply piece that has brass tubing epoxied in? Any feedback will be much appreciated. The problem is that once I complete the sheeting and covering, it will be near impossible to replace this part without major surgery. So if I have to discard the plastic bit and replace it with a ply part, I'd rather do it now.
|
![]() |
|
| Tony Leong | Tuesday Mar 12 2013, 10:31 PM Post #5 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
My building board is a little too short to build this wing in one go, so I am starting with the port wing first.![]() Adding the leading and trailing edge sheeting. ![]() Then continue to add the starboard wing. ![]() The accuracy of the laser cut parts is very good and assembly went on smoothly without any need to have to make any fitting adjustments at all. I'm enjoying the build very much.Its always a pleasure when the kit comes together as it is supposed to. |
![]() |
|
| Tony Leong | Wednesday Mar 20 2013, 11:46 PM Post #6 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
UC legs are wing mounted on hardwood bearers.![]() Bellcrank group has 4 inch bell crank held in place by two brass bearings that are soldered in place. ![]() ![]() ![]() The balsa cap strip 1/16 x 1/4 supplied was insufficient. Short of about 1.5 strips. ![]() So out came the balsa stripper. Once set up, I continued to make up a bundle of strips as this is a common size for cap stripping and most kits I have built almost always under estimates the quantity needed. ![]() The wing tips of the United is carved out of a massive 1.5"x1"x9" balsa block. Lightweight balsa blocks was supplied. ![]() Hollowing out the wing tip blocks. Quite a bit of elbow grease needed here. Having a Dremel and a carbide ball router significantly reduces the time needed to hollow out the blocks. Thankfully, the balsa supplied was light weight and consistently soft making it easy to carve/route the blocks. ![]() Wing construction completed. Still needs installation of the flap horn, hinges and final rounding/sanding. I'll do that later. I shall be moving on to the fuselage construction shortly. ![]() Edited by Tony Leong, Thursday Mar 21 2013, 12:18 AM.
|
![]() |
|
| Tony Leong | Saturday Mar 23 2013, 12:56 AM Post #7 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
Weight box installed.![]() Started building the fuselage. Found an issue with the balsa fuselage sides provided. It terminates at the engine bulkhead when it should have an extension to match the ply doubler. ![]() Thinking that it may have been my fault and that I may have accidentally cut it off by mistake. Fortunately, I still had the balsa scrap for for the parts concerned and I placed the fuselage sides back. It confirmed that its a laser cutting mistake. It appears that the balsa sheet is too short to include the nose extension and a decision must have been made to terminate the balsa sides at the bulkhead. ![]() Its easy enough to cut the rectangular pieces and glue it onto the ply doubler but this is not shown on the building instructions nor is the builder informed of this change. I cut the missing pieces from scrap balsa and glued it on. ![]() Edited by Tony Leong, Saturday Mar 23 2013, 01:02 AM.
|
![]() |
|
| curare | Saturday Mar 23 2013, 06:47 PM Post #8 |
|
Addictive Poster
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
Looking good Tony. Hope your neck is much better and that you'll be able to maiden your Nobler tomorrow. |
![]() |
|
| Tony Leong | Sunday Mar 24 2013, 11:54 PM Post #9 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
Thanks Francis. Neck much improved though still a pain in the neck (literally) LOL!. Maidened the Nobler today. I'll post the report. Cheers. |
![]() |
|
| Tony Leong | Monday Mar 25 2013, 12:07 AM Post #10 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
The instructions describes the installation of a 1/2 in balsa spacer between the two engine bearers. Its called a dampener. The parts list for the kit includes a "dampener (motor mount spacer) 1/2 x 5/16 x 5-1/4". A piece of balsa wood with this dimension was found in the kit. However, the damper (or spacer) should actually be 1/2 x 1-5/16 x 5-1/4 to fit in the space between the bearers. The part described in the parts list and supplied in the kit is 1 inch to short in width for the purpose. This is clearly a kit production error. In any case, a rummage through my scrap wood box produced a suitable piece of 1/2 in balsa and a little work on the disk sander produced the piece of 1/2 x 1-5/16 x 5-1/4 needed to proceed with the build. ![]() The picture shows the spacer installed with the second fuselage side added. It can be see from the picture that the ply fuselage doublers are oversized in that the sides should be flush with the engine bearers but is in fact about 1/8" above the engine bearers. The extra bit will have to be cut off and sanded flush with the engine bearers in order for the cowling block to fit in properly later.
Edited by Tony Leong, Tuesday Mar 26 2013, 11:07 PM.
|
![]() |
|
| Tony Leong | Tuesday Mar 26 2013, 11:27 PM Post #11 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
I swapped the ply formers F4 and F5 with parts I made out of 1/8" and 3/32" balsa sticks. The ply formers supplied were undersized. I also added a 1/8 balsa stick reinforcement to F6 (shown below). F6 is from 1/16 balsa with the grain running vertically. This would make it quite vulnerable to snapping if too much pressure is accidentally applied to the fuselage sides eg when loading into the car etc. I've had RC planes with similar construction and its heart wrenching to hear the sickening crack. Though the block balsa turtle deck and bottom decking will prevent the fuselage from caving in, it might still end up with concave fuselage sides. So I added in a 3/16" square balsa stick to make sure this doesn't happen. A stitch in time saves nine.......![]() I discovered yet more missing parts. The cowl is made up of 2 pieces of 1" block sandwiched between two 1/4" balsa sides. From looking at the instruction booklet's photos, the 1/4 sides appear to be laser cut parts but none were supplied in the kit nor listed in the contents list. Fortunately, the plans does provide a pattern for the par which I photocopied and used to cut the two missing 1/4" balsa pieces from my stock of scrap balsa. ![]() ![]() ![]() Edited by Tony Leong, Tuesday Mar 26 2013, 11:30 PM.
|
![]() |
|
| Tony Leong | Friday Mar 29 2013, 03:10 PM Post #12 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
Here are the fuselage blocks ready for shaping and carving.![]() ![]() And 4 large bins of balsa wood shavings and dust later.......we get the hollowed out turtle deck and bottom ready for mounting and final finishing later. I've not seen so much balsa shavings coming from a single model for a good several decades, back in a day when we carved leading edges out of 1 inch thick balsa for our combat CL planes eg. Ironmonger et al. For quarter scale RC, we tend to plank sheet balsa with ammonia to allow the balsa wood to be more easily shaped and molded.
Edited by Tony Leong, Friday Mar 29 2013, 03:15 PM.
|
![]() |
|
| Tony Leong | Sunday Mar 31 2013, 03:26 PM Post #13 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
Enya SS45 S-PL Pro (Ringed) with the Fox 1/2 inch prop shaft extension.![]() Turtle deck and fuselage bottom blocks tacked glued on for shaping. ![]() Cowl block tacked glued. ![]() The air intake appears to way bigger in area than the exit. The air exits through the engine bulkhead and the area of the opening is even smaller than the air exits. This is possibly going to lead to cooling issues. Not a good thing with the heat here in Singapore. I think I am going to reduce the size of the air intake. It will make it easier to carve the intake block too. ![]()
Edited by Tony Leong, Sunday Mar 31 2013, 03:42 PM.
|
![]() |
|
| Tony Leong | Monday Apr 1 2013, 11:49 PM Post #14 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
I reduced the intake area.![]() Time to fill up a few bins worth balsa shavings and dust (cough cough) ![]() ![]() I've added gussets (made from scrap 1/4 square balsa) to reinforce the joint between the ply mount and the balsa cowl. This joint is particularly weak and since the mount is the only thing that holds the cowl in place, I will reinforce it further with fiberglass. I can't figure out the idea behind designing the mount this way. The front of the cowl is held in place by a 1/8 dowel inserted into a slot cut into the nose ring (ply) and the only thing that holds the cowl in place is a single bolt at the rear of the cowl. Vibration from the engine will likely cause the cowl to flap and the stress this will impart onto the weak ply mount will probably lead to catastrophic failure within a couple of flights. I will insert a pair of hardpoints onto the nose to allow for two additional screw points to allow the cowl to be more securely mounted to the fuselage. ![]() ![]() As the turtle deck and bottom fuselage decking is only tack glued to the fuselage frame for the time being and left slightly over sized until the completed wing and tail is mounted, I won't bother to sand the cowl and just leave it at its present semi finished state. I will do the final sanding, shaping and blending after the turtle deck and bottom are glued on permanently and sanded. I intend to finish the cowl with fiberglass. ![]() Edited by Tony Leong, Tuesday Apr 2 2013, 12:18 AM.
|
![]() |
|
| Tony Leong | Tuesday Apr 2 2013, 10:59 AM Post #15 |
|
Avid builder of models
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
The tack glued bottom decking removed from the fuselage frame and air exit holes being carved out.![]() I still can't figure out the arrangement for mounting the finished cowl to the fuselage. The instructions says to cut a slot on the nose ring to allow the peg on the cowl to fit in. In essence, the slot is just a key slot to allow the cowl to be positioned. It doesn't hold the front end down. The cowl is mounted with a solitary bolt at the rear. I can't see how a cowl mounted this will stay mounted for long. With every stroke of the engine, the front of the cowl will flap, perhaps just a little but at 9,000 strokes a minute, it won't be long when the flimsy rear ply mount will give way and detach from the cowl. I've strengthened the ply mount joint with 1/5" balsa triangle gussets but still, I have little confidence about its longevity. Perhaps, if this was an electric powered model and a pair of super magnets used in the front to hold the front end of the cowl down, it will work but with a bone rattler 45 sized internal combustion engine............ummmm?? ![]() I think I'm going to embed a pair of hardwood hard points on the front of the balsa cowl and than secure the front of the cowl using a pair of counter sunk wood screws from the front of the nose ring. It'll mean having to remove the spinner before the cowl can be removed, which will be a royal pain. The alternative is to mount with a screw from the top of the nose. A little bit uglier with the bolt hole showing on the pretty nose but it'll allow the cowl to be removed without removing the spinner. Still have time to think this through as the mounting arrangement won't have to be finalised until the wing and tail is mounted.
|
![]() |
|
| Go to Next Page | |
| « Previous Topic · Building · Next Topic » |
- Pages:
- 1
- 2





![]](http://z6.ifrm.com/static/1/pip_r.png)













































