Hi,

I will be using a YS-160 DZ on my OTOP. Now I need to order the extra bits and pieces such as Hyde mount, manifold and pipe. I would like to ask the OTOP owners what kind of manifold/pipe setup they use with OTOP. The plane has the pipe mounts aft to the fusellage I don't know whether I could use the Hatori short pipe in such case?

- Do you use a short pipe or long pipe with OTOP?

- I am leaning towards Hatori (HA 821). For this pipe there are two options for the manifold, 1) Manifold HA822 which locate the pipe in front or 2) Flexi manifold which is longer so that the pipe is located towards the centre of the fuselage.

- What is the difference between HA 725 and HA 821? They are suggested for use with the 160 but which is more suitable for that particular application really?

I really look forward to your suggestions. If you have any photos from your setups please send some.

Thanks in advance,

Nikos

PS: Inputs from non OTOP owners but with experience on YS 160 muffler setups, is more than wellcome.

Nikos,

I used the NMP header from Central Hobbies which will work with the Hatori pipes as well.
The header aligns the pipe dead center in the pipe tunnel. Just a note on mounting the engine;
on my OTOP the nose is angled for right thrust but the firewall is installed square so I had to
make a shim to angle the Hyde mount the correct amount for the desired right thrust. I used
an ES Composites carbon fibre pipe which is fairly long but I believe any length pipe will work.

tommy s

Hi tommy s,

Thanks for your answer, I have some questions though:

- Is there any pre-build right thrust on the firewall? I don't understand what you mean really by "the nose is angled for right thrust". How can the nose be angled and not the firewall?

- How much right thrust did you add? There is no such indication in the manual.

- How did you screw the mount on the carbon firewall? Did you use just blind nuts or normal safety nuts? Does the mount come with screws?

- Which pipe from the Hatori pipe line is more suitable for OTOP you think?

Looking forward to your reply,

rgrds,

Nikos

Nikos,

I don't know if they are all built the same but on mine the firewall is square with no right
thrust built in, but if you mount your engine that way the spinner gap will be uneven because
the nose is built to accomodate right thrust. I used a Hyde ARIA mount with the built in nose ring
and offset it slightly to the left of center on the firewall and made a shim to go behind the mount
to angle it slightly for the desired right thrust. I don't know how much it's angled, I just made it fit
even with the spinner back plate.
I used regular locking nuts on a plywood ring behind the firewall for mounting the motor mount.
If I was building another one I would use the Hatori short pipe

tommy s

Hi thanks once again for the answer.

Do you think that the Hatori short muffler can be installed in front? The open belly area is pretty short isn't it ? How would you mount the short pipe on the fuselage? The place to be mounted does not seem as rigid to me, it has to be reinforced somehow to accept the pipe mount.

COULD I HAVE A PHOTO FROM YOUR SETUP PLEASE WITH HEADER AND PIPE MOUNTS, PLUS THE EXACT MODEL OF THE PIPE?

Also what servos did you use for the elevators? I plan to use JR mini digis 3421 if not mistaken.

Looking forward to your suggestions.

Thanks in advance,

Nikos

Nikos,

I purchased all the exhaust parts from Central Hobbies. I used an NMP pattern header,
NMP pattern pipe mounts, and an ES Composites pipe # ESD4C160C7 .
I glued two 1/32" plywood discs on the inside of the pipe tunnel floor to support the pipe
mounts as the tunnel floor is balsa and didn't look strong enough by itself. One of the
nice things if you use the Hatori pipe is it doesn't need any support at the front, only at
the rear. I used the short pipe on a previous model and it makes a neat installation. I am
happy with the ES pipe also as it's extremely lightweight and quiet.
I used JR 8411sa servos on all the control surfaces and a JR 3421sa on throttle. I have the
DEPS elevator control system in mine and it works very well, no slop and no friction, but it
was a pain in the butt to install. You probably already can see there is very little room in the
rear of the fuselage to install the DEPS and the rear diagonal brace is right in the way. It's
the best system I think but it's not very easy to install because of the limited room in the OTOP.
I'll try to post some pictures when I get home tonight but if you look on the Central Hobbies
web site they have good pictures of everything I used.

best wishes
tommy s

OK thank you!! Your advice is very valuable!!

Do you believe that I could use the short pipe with no issues at all?

- I will wait for you photos I just would like to see, if possible, the stand you made for the pipe inside the tunnel.

- Regarding servos, yes this is what I also think of 8411SA, plastic gears for sure. I have excluded the DEPS system I will open two little servo slots in the stab and that's it. Specially if I use the short pipe in front the plane will balance just fine.

- Do you believe I could use MK servo horns on surfaces? I wonder whether I coulld drill them an place those nice servo horns with the ball bearings....

Best regards,

Nikos

I think the short Hatori pipe would be an easy installation. I didn't make any stand for the pipe
mounts, just glued a small piece of plywood inside the pipe tunnel sort of like a washer so the screw
wouldn't pull through the balsa.
I used MK control horns on mine but didn't use the screws that go through the control surface. I used
the ones with the triangular nylon base that angles the control horn over the hinge line and screws to
a triangular piece of plywood that is glued to a recess in the control surface. These are the same kind
that OXAI uses on their airplanes. The Central Hobbies part# is MKD0815. I don't think the ones with
the one screw would be strong enough because the composite control surfaces are hollow.

tommy s

Hey Tommy thanks once again.

I know which MK horns you mean. Thanks I will get some of those, what pushord length did you get really for the ailerons? I think MK provide some fixed lengths.

The issue with the short pipe and OTOP is that, the pipe should be placed on the composite part of the fuse the one covered by the small belly pan. Is that surface rigid enough to hold the pipe or need some kind of re-inforcement?

Here is the photo from the manual. The pipe should be placed on the wide area right?

I think that things started to become more clear to me. Thank you very much.

Any more advice is more than welcome.

Best rgrds,

Nikos

Nikos, I think the Hatori pipe is long enough that the mount should be just inside
the opening for the pipe tunnel. If it was me I would glue a small piece of plywood
on the inside of the tunnel for just a little support for the mount then you will have to
cut an opening for the pipe stinger on the belly of the airplane.

I used carbon fiber push rods with titanium ends so they can be cut to any length you
need them. I also cut openings and glued servo mounts inside the wings so the servos
could be mounted outside the wings like I've always done on my other airplanes. The
internal servos were just too much trouble to mount and dismount and this way I could
use my regular servo arms.
Oh, I almost forgot...those little plastic screws that hold the lower cowl on , throw those
away and replace them with metal ones , they will break after a couple of flights.

tommy s

OK Tommy thanks once more.

Wish you nice landings!!

Nikos

Hi Tommy I have another question for the Hyde mount you used.

You said you used the ARIA which means: R:Ring, I: Built in nose ring, A: Alloy beams right? Did it fit well in terms of length? Did you use the already drilled holes of the mount or you had to drill some new ones? Do you believe I could use the ARA version where the ring is installed behind the cowl nose?

To be honest I would like to use the most simple version, the A type. However this is not currently available so I have to find the best alternative.

Looking forward to your reply,

Thanks in advance,

Nikos

Nikos,

The ARIA mount was a perfect fit -- I used the predrilled mounting holes and the length
with the DZ engine was exactly right. With the small plywood spacer behind the mount
( no more than 1/16 in ) the spinner gap is very small, probably around 1/32 in. The only
problem with this mount is the price, over $200.00 .
I haven't seen any other type mount in an OTOP but I don't see why they wouldn't work.
Budd Engineering makes a nose ring with a mount just like the ARIA that bolts to the
firewall that can be used with any kind of mount and it's reasonably priced, around $55.00 .
That might be the fastest and easiest way to go.

www.buddengineering.com


tommy s