RE: Building The Arrow
 

I still have an old MK arrow that needs restoring, the best pattern plane I ever had

RE: Building The Arrow
 

David,
Thanks for going to the trouble to load the Arrow articles, they worked a treat! I have both magazines but it is much easier to find and read on the computer than it is going out to the shed to wade through dozens of mags. For some reason I feel the need to fly an Arrow again.http://www.rcuniverse.com/forum/js/f...ular_smile.gif Matt

RE: Building The Arrow
 

Hey Matt, no worries. I 'm glad that was of help.

I'm feeling the need too - maybe this winter I'll get to mine. In my case it's an MK 40 size version which will have a YS 45 FR, Hatori pipe, MKgear &wheels. It will be cool!

David.

RE: Building The Arrow
 

Any one notice something interesting about this picture!?

That looks like DB with his Tipo at what I suspect is a third place at the '79 world's. How can I tell?

See the first place wing tip?

Thanks for the photo Ray - sourced off Trenton.

I had assumed that the '79 worlds were in Mexico and not South Africa but those must have been the '81 world's were Hanno eventually succeeded with his Magic. Did Hanno actually manage to fly in SA in '79? Is he to the left of Matt on that podium?

David.

RE: Building The Arrow
 

Yes this is the '79 Worlds held in South Africa. Matt was first with the Arrow, DB second and Mark Radcliff third.

'81 Worlds were in Mexico. Prettner first, DB second and Matt third, again flying the Arrow.

Hanno was not in South Africa - this is why.

Ray

RE: Building The Arrow
 

Ok I have started the build ther is no turning back now !!!

I am starting with the Engine mount areaI think this is the place to start ,once thisthis is right and fits the OS61V, we can move on to easyer parts.

I a Cut out and shaped two alloy plates, for the engine to rest on to give added strength and stop the Engine lugscuttinginto the wood

1stPhoto:- I have cut out all the parts to make up the Engine mount

2nd Photo:- I have test mounted the engine to make sure there is Enough clearance for the spinner after the nose ring is glued in place

3rd Photo :- Assembled mount modified and drilled to fit OS61 V

4th Photo :- I chose to not use Blind nuts as they sometimes come loose, I have used Dubro 4-40 inserts and epoxyed them in place


I will be Sorting out Fuel tank mount and fire wall next


Johnkpap

RE: Building The Arrow
 

I decided to build the two sides next......This took a while to work out

The sides stop just past the fire wall (This part's Drawing is showenincorrectin view "AA") After gluing on of the 1/16th doublers I have glued it it to the engine mount
assy, the former making up the back of the Fuel space "CC" has also been fitted. The fuel tank I am using is slightly shorter and round, I have added some scrap balsa for it to sit on.

The final shot shows it over the plan, Every thing looks straight and true, I will do some more over the next few days, it has take a while for me to get my head around how this model is actualy built
I have had to re-cuta fewparts so they fit because the views of some parts are not quite right. Also the OS 61 V is slightly more wide compared to the webra 61 RE.

I suspect there will be lots more fun to be had as I progress through this build, I Suspect I nowKnow why the MANMag Editors Wrote

:- "Construction of the Arrow as showen on the plans should pose no problems for any ,and detailed plans are hardly needed"

looks like I am in the Experienced Builder Zone

Johnkpap

RE: Building The Arrow
 

I stayed up late last night, I attached the nose ring, made out of 1/16th ply and installed engine bay sides and balsa fill blocks.

I test fitted the engine, yes it stillfits.

I also found my first stuff up's !!!

- I only used 1/16th sheet for the tank floor,should be 1/8th (Fixed by gluing a another 1/16 sheet under it)

I also cut the lower block out of 1/4 inch not 1/2 inch :- did the same cut two more and glued them together....All is good

So far no major mistakes, I can see now why MK Arrow kits go for silly $$$ on E#a$ Auctions, A kit would be Easyer

RE: Building The Arrow
 

That's looking like a tight squeeze John.

Will you have the space to advance the throttle without interfering with the nose ring (or spinner backplate http://www.rcuniverse.com/forum/js/f...ey/msn/eek.gif). I'm surprised the Arrow fuse width is that narrow.

You already measured out your header and tank on the plans so all's well there Ipresume. From the last picture it looks like there isn't enough room for the header to clear the tank but it's hard to tell.

Cool... an Arrow build. May it progress smoothly.

David.

RE: Building The Arrow
 

Using the old Model Shop stock MAC's HeaderI bought some time ago, it clears the tank exactly as on the plan, i have to tidy up the engine bay so the throttle will clear.

Yes there is no alot of room in the engine bay Every thing must be planed well in advance orI could be in a world of pain (Start from scratch Noooo!!!)

I will do some more Build soon.

RE: Building The Arrow
 

Oh yea. That's looking good John!

It's awful to be concerned about someone else's build - especially of such a rare beauty!

BTW, look what arrived in the mail today... http://www.rcuniverse.com/forum/js/f...sn/biggrin.gif Little sibling look familiar?

Onward, David.

RE: Building The Arrow
 

Nice OS 25 ....Hmm what about a smallArrow and call it a Dart http://www.rcuniverse.com/forum/js/f.../thumbs_up.gif

I will get back to the Build, I am trying to workout how to build the cover to go over the pipe, so far my best Idea
is to cut out a blank out of polystyrene with my hot wire, cover it with epoxy and glass cloth and while still wet cover this with a layer of 1/64 inch ply
then paint the ply with epoxy. Let the whole thing set for two days the desolve the polystyrenegiving me with a light strong cover.

If anyone has a better Idea please I want to hear it

Johnkpap

RE: Building The Arrow
 

John,

you read my mind. Plans are swirling in my head.

Upon careful inspection, it would have been nice for MANto delineate the fuse sides more clearly.
<ul>[*]If Iunderstand correctly, they run horizontal just under the TP floor (floor is attached overtop), then they angle downward to section GG with a notch up at FF to make the TPfloor flush with the sides and run horizontal again from GG to the tail.[*]Along the bottom they run flush with the doubler marks foreward of the wing LE with the retract bay floor bounding this box in a similar fashion to the TP floor (the section drawings help here). They follow the wing airfoil contour but break away from it before reaching the TE and continue at an upward angle toward the tail. It appears that the two 3/8" side sheets take care of finishing off the side above the wing TE.[*]The side fronts appear to end, again, flush with the doublers so that the engine compartment rear (tank) 3/16" ply bulkhead attaches primarily to the 4 pieces of tri stock around the tank bay. The engine bay sides then are an extension of the fuse sides.[/list]What's a bit of a mystery is the fuse bottom forward of the wing LE. I assume they have two 1/2" sheet sides with a block placed in between underneath the engine up to the bulhead marker. It's not clear whether there is supposed to be a balsa or ply bulkhead at the end of the block where the gear mounts but I suppose this is optinal and depends on whether one is using a FWmount or belly mount gear. For the latter, it seems strange though to have to sheets of 1/8" balsa prior to hitting the 1/16" ply engine compartment bottom. Another piece of ply would have to be glued to the tank floor bottom to support the belly mount gear.

Section BBis a little odd. Ithink there's a mistake there. The 3/32"ply bottom should actually be show in section CC as it represents the gear bay rear and wing mount dowel support. This is marked as being a piece of 1/4" balsa (?) sheet in the side view. That is unusual - ply on the wing LE but balsa on the fuse support!?

I would redesign (reinterpret) this section to make the ply bulkhead at CC to extend below the tank floor to the bottom of the fuse - one single piece. It would have a curved contoured shape along the sides in the pan area to follow the contours shown in CC. I'd make this former out of 1/8"ply and then laminate another piece of 1/8" ply ahead of it under the tank floor at the rear well location then glue the two sides of 1/2" balsa end on and re-inforce the joint with 1/4" or 3/8" tri stock. The wing belly pan front would then be made of 1/8" ply to support the dowel. Ithink Imight also bring the fuse sides down to the wing chord CL so the belly pan sides would intersect the fuse sides at the wing LE. No mention is made of how the belly pan is framed up but standard methods can be used. Maybe 1/8" sides and bottom with tri stock at the joint. The rear section of the belly pan and the fuse junction could be made of two pieces of 1/8" lite-ply. Instead of using one dowel at the front, I'd be inclined to using one on each side leaving the middle section clear for the nose gear and providing a little added peace of mind.

On second look, I have re-interpreted the fuse side view at the wing LE. Iwould still built it according to my re-intepretation above. What's missing from section CCis to show that the former must extend below the tank floor and that the latter should end flush with this bulkhead. The plans make it appear as though there are two sections of 3/32" ply and this would be quite weak compared to a single former of 1/8" ply backed by another laminated piece of 1/8" ply at the wing insertion point.

Hope this is not too much rambling. Any suggestions or different reads are welcome.

David.

RE: Building The Arrow
 

John,

I'm not sure if your idea is to just make the rolled section that covers the pipe but not the header and build the front part as shown in wood.

If that's so, here's a variation on the theme. Rather than using 1/8"balsa for the pipe floor, consider 1/8" lite-ply. Only run this floor from the top of the tank bulkhead to section FF leaving you with clearance to pass the header back. This floor would be sanded flush with the fuse sides as shown in the section views.

Once the rear top turtle deck section is finished (3 slabs of sheet wood - a tad heavy if you ask me), you'd tack a rectangular block of white foam running the length of engine mid-cylinder to section FF. The foam would temporarily float forward of the tank bulkhead. The rear section of the block could be cut at an angle as shown prior to tacking. Then, make two identical templates of the fuse side in this area and tape them on either side of the foam block. These are used to sand the block top to side view. Then remove the templates and sand the sides flush with the fuse and round out as shown in the picture below.

You can then use this as a mold to glass it as you describe to make a solid FG fuse top. There would be no need for 1/64" ply. Depending on how hot things get, you could always cut a cooling slot on the top at the pipe rear section. The important thing is to allow air to flow through the duct.

To mount the FG pipe tunnel, you can simply install three hardwood blocks on each side holding the tunnel down with 6 screws. To insure the tunnel is centered along its length, you can run 1/8" hardwood longerons along the floor in between the blocks.

This approach would be more akin to how a FG pipe tunnel would be installed on a FG fuse. I think you might find it easier to deal with the tunnel as a single piece rather than having to match an inverted U shaped tunnel to balsa sides and canopy area. It also gives you considerably more access to the pipe area for adjustment. Ibelieve this is how the MK Arrow 60 kit does things. A set of MK plans would be helpful as they tend to be quite detailed. I suspect the model in the photo below was built from an MKkit. The pipe tunnel screws can be seen in the picture. Actually they show 4 screws on each side if you look carefully. If you look at Matt's tunnel design, it looks a tad more complicated.

David.

RE: Building The Arrow
 

I found out that the 25 VF DFis suposed to reach 1.1 bhp @ 22k rpm http://www.rcuniverse.com/forum/js/f...bout_smile.gif

Iwonder if it can do this on a piped APC 9x6 on 15% fuel!?

Bryan (Roguedog), if you catch this, is your 25 VF a DFmodel? Do you have any run figures for it?

David.

RE: Building The Arrow
 

Thanks David for all your input, yes you too have found some errors in the plan,the one that has given me the most trouble so faris the fire wall, I had 3 goes at cutting this bit out,
I have also made up the parts for where the front gear mounts, the nose gear unit I have chosen fits in just fine, I will have to cut down the legs so the wheel can be fitted and clear the
wing mount area.

I have been buying up all the Arrow components for about a year, the Idea came from the "$5 Arrow wing " at last years Club Auction.

We have a Holiday weekend here in South Australia and its going to Rain all three days this means no flying just building, I will hopefully get to my LHS at some stage

Also Does Any one Have "Lith Plate" ? or know where I can my hands on some, it was usedin older printing press systems, I had some once It would be just the
thing to cover the base of the pipe bay.

My other Idea calls for a number of Beer Cans !!! Drink the beer and cut the can up to make thin sheets and use that. The other option is to buy some K&amp;S Sheet.

RE: Building The Arrow
 

John,

You're welcome. I'm building vacariously through your thread.http://www.rcuniverse.com/forum/js/f...sn/thumbup.gif

Yea, the fomers are tricky to cut - not as simple as they appear at first glance.

you could also substitute the 1/8"balsa pipe floor for 1/8" lite-ply and bond some aluminium foil to it. If well ventilated, I suspect that a well painted fuel proof floor will also hold up well, especially if painted metallic aluminium http://www.rcuniverse.com/forum/js/f...sn/biggrin.gif

I finally dug up the plans for my MK Arrow 40. Although the scale changes things a bit with the 60 (I don't have those plans but they would be most welcome if anyone has them), the photos below should help to clarify a few things. In the MKbasically, they omit all the various tank/engine floors shown in the MAN plans (seemed a little redundant). Instead, they simply make a sandwich between the two nose gear sides consisting of the front curved block, a ply gear floor (I'd use 1/4" on the 60) and a 3/16" balsa tank floor behind the gear mount back to the former extending into the gear area just in front of the wing LE. Tri stock is used to re-inforce the junction of the former with the gear sides. One can see this former clearly as I described above. Either Iremembered this from the plans or it must have made sense to build it this way.

I'd watch out for installing the nose gear prior to mounting the wing and main gear. The wing will dictate how long your nose gear and wheel needs to be. It might be that you'll have to mount the gear a little further forward to ensure you clear the wing support former. Also, it might give you a little leeway to make the gear a tad longer for that 12" 61 VF prop.

Also, note how the fuse bottom rear is made with three formers, a stringer and some molded balsa sheeting. Much lighter!

David.

RE: Building The Arrow
 

Thanks David for the Arrow info, yes this helps

I have found what I need to cover the inside pipe tray, they use alloy foil shielding in some old computer equipment
I have some taken out of old keyboards it has a plastic backing on one side but it does not burn easy so it should be fine to keep the heat out
of the body of the plane, the last thing we want is Radio fail Due to heat from a hot pipe.

I am going to Cut out more parts tonight and make up templates to make a foam core for the tail and a Foam pipe cover blank tomake up a
fiberglass cover.

If someone has a MK60 Arrow could they post photos of the pipe cover

Regards

Johnkpap

RE: Building The Arrow
 

John,

the pipe cover on the MKkits (40 &amp;60) is actually a fuse upper section. It is an entire FG piece that sits atop the pipe floor and includes the canopy forward section. Iattempted to describe this piece (or how to go about making it) above in an alternative to the pipe tunnel as on Matt's plane. The part can also be seen in the picture of the MKArrow Iposted above where Imention you can see the 4 screws (per side) attaching the top to the fuse.

All the wood components of the fuse build are shown in the photo of my MKplans I posted above. You can see there are no canopy parts made from wood.

Hope this helps, David.

RE: Building The Arrow
 

I have built some more http://www.rcuniverse.com/forum/js/f...sn/biggrin.gif


I have installed the Top deck and the sides for the pipe tray, I need to now (once the glue has dried) sand and carve things a bit so the engine and pipe all fits as once I put the wood c anopy area in place this is going to make shaping a bit difficult, I am going to make this assy up separate once I have shaped the inside i will glue it in place and renforce it with thin fibreglasse inside where the pipe leaves the engine.

I am now at a point where I can see if my $5.00 Arrow wing will fit , Yes it fits http://www.rcuniverse.com/forum/js/f...sn/biggrin.gif

I am now working out how to mount the front retract, and then cut out a foam Pipe cover Blank out of foam to make a glass/wood cover</p>

RE: Building The Arrow
 

Building a pipe cover, this is the bit I put alot of thought into how to do this.

After all the Ideas went trough my head, I came to the following answer :Fiberglass http://www.rcuniverse.com/forum/js/f...sn/biggrin.gif

So I cut a block of foam with my hot wire 45mm long and deep enough for the blank. I made two templates
1.5mm smaller than the required size out of 1/16 light ply and sanded them nice and smooth, I put a template at each end of the foam block
and cut out the blank (just like a wing core) after about 4 goes I had a good one.

I then checked that it was the right stuff by placing it on the fuse and comparing it to the plan, all looks good.

I glued the blank to a balsa block and then on to a plastic covered board, I applied the fiberglass and laminating resin as follows:-

1. Paint core with a thin coat of resin

2. Apply a layer of medium glass cloth

3. Paint more resin

5. lay 6 strips of Kevlar String (I get this from the Guys who install Optical Fibre FREE)

6. Add a layer of heavy glass cloth

7. Add a layer of very light glass cloth

8 Paint on more resin and smooth down with your gloved hands

I now have to wait for it to set 12-24 hours, I hate the wait


While the mess is setting,I will start installing the front retract assy.


Johnkpap</p>

RE: Building The Arrow
 

The pipe cover is now set enough to remove from the board,I cut it away with a Xacto knife and trimed up my work,
as you can see from the pic it has worked out .

This method of building one off parts seems to work very well, you could use it for making more than one without going to the (time/cost$$$) of making a mould

Once the cover has fully hardened I will desolve the foam with some acetone, leaving me with just the cover trim/sand it to shape and test fit it in place.

From now on the build is very straight forward only a Foam tail plane and balsa parts and lots and lots and lots of sanding to do.

RE: Building The Arrow
 

Looking good John!

Can't wait to see some wide pictures!!

David.

RE: Building The Arrow
 

I am at a point of the build where things are coming togeather, The pipe cover is dry and De-foamed
and the front Retract is installed with greater than 12 inch's of prob clearance, the wing fits but does not bolt on yet.
The engine and pipe fit as planned, and the cover goes over with room for cooling from air flow.

I havebalsa blocks to glue and then its time to sort out the wing mount issue :&gt; because the wing came from a glass fuse the wing mount bolts
don't align up,balsa is thicker than glass, I am going to use reversed DUBRO wing bolt mounts reverse them and recess the curve into the fuse.

On with the build I have blocks to cut and a wing to mount.

RE: Building The Arrow
 

Where am I at ?

After alot of messing around I have a wing that bolts on....I still have to beef thingss up a bit more with a ply plate and a area of glass cloth
after I fit the back plate for the wing to sit on.

The last thing I want is the wing to pull off in a inside loop http://www.rcuniverse.com/forum/js/f...spinnyeyes.gif

I have cut out the foam blanks ready to cut a pair of fins, plus some of the balsa tail parts, I am not going down the plug in tail
road this looks like alot of work. I am just going to cover the foam with balas and join the halfs with glass cloth.

No pics yet nothing worth posting.

Any body got a Variable pitch prop and a Pair of Graupner Spoilers......they would like to donate http://www.rcuniverse.com/forum/js/f...sn/biggrin.gif

If this thing fly's nice and dosn't scare the hell out of me I may make a second wing with Dual servos and a set of spoilers
Just to see what they do on an Arrow.

http://www.hobby-lobby.com/spoilers.htm

I am not sure if these are even avaliable any more





more soon

Johnkpap




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