Timthetoolman1

My Feedback: (6)

I want to mount the engine inverted on the two bipes I'm building because:
1. It gets better cooling.
2. It balances the weight about the longitudinal axis.

These pictures are of a Saito 91 on a practice cowl. I will have my Saito 1.25 next week end and it's only slightly larger.
What do you guys think?
Could someone with the Saito 100 side mounted, or inverted, post some pictures. I would like to see any pictures actually Thanks, Tim

rcmiket

Sure would look better sideways' As far as balance its not going to take much out there on the wing. I've always mounted mine sideways without any cooling issues. Mike

Timthetoolman1

My Feedback: (6)

That looks good Mike. I used a Hayes mount which is symmetrical so I will rotate it sideways and see just how much cutting I'll have to do.

gnirwin

My Feedback: (25)

I am also getting a Sait0 1.25 for my Ultimate. I was wondering how I was going to mount mine so please keep us posted as to how yours works out.

tukkus

My Feedback: (2)

I just ordered a CG ultimate(noone has any Sig Hog Bipes in stock) from Tower and i'll be mounting my engine(ys 1.20) inverted...I think it looks better inverted. Mounting on the side to me looks odd because there is nothing on the other side to make it look symmetrical.

rangerman, have you done or plan on doing any mods to the Ultimate? I plan on going with the landing gear from the Bucker Jungmeister.

The owner of the plane in the picture is Big Bird.

I'm sure it will look good either way you mount it, good luck

Timthetoolman1

My Feedback: (6)

After looking at it again, I don't like the engine hanging out but I am not going to get another exhaust and I don't like the fact that the muffler would have to run inside the plane and there is no protection for the fuse from all the gas. I'll mount it sideways later and see but so far I like external. Putting weight on a wing to compensate might increase rotational forces or oblong rolls-just a thought because I have no experince in such matters.

I have made some changes. So far I've cut a new 1/4" 5 ply firewall and have coated one side already with epoxy. I'll cut 1/4" notches in it because I'm also using 1/4" bass wood stringers instead of the two 1/8" and the other balsa stringers.

I've been trying to find other landing gear so I'll go check those out. I would like carbon fiber but I haven't found any yet.

FlyingPilgrim

My Feedback: (26)

I am still working (slowly) on my CG Ultimate. I mounted my YS 1.10 on it's side. After having done so, I wish I would have mounted it inverted. It is a pain to get the cowl on and off without lots of pushing/pulling and force to get it around the muffler. I had to cut the muffler hole larger than I wanted to in order to make the cowl removable with exhaust intact. It looks OK (I'll post a pic later), but I think it would have been easier and cleaner looking inverted. As far as balance difference with side mounted, I doubt it is enough weight displacement to make a big difference, and any out of balance condition could be corrected with minimal lead in port side wing tip.

johnyh

I've got the World Models 120 Ultimate and have a side mounted OS 120, the weight was no problem for balancing

Chuckar

My Feedback: (1)

I have two CG Ultimate this one has a YS 1.20 in it mounted at 90 degrees this plane ROCKS !!!!

FlyingPilgrim

My Feedback: (26)

Here's my cowl cut outs:

FlyingPilgrim

My Feedback: (26)

FYI, on my kit I added an additional forward deck former that I fabricated out of balsa to hold the stringers straight. It is visible just behind the blue struts.

FlyingPilgrim

My Feedback: (26)

One other note for those building: I found the fuse doubler was cut incorrectly on one side, and did not match the other side's location for the rear wing mount. It has an offset for the LG wires, but there should not be any offset for the wing mount blocks! I had to cut and fill to make it symetrical (visible 3/16" filler behind hardwood wing mount).

The other pic shows some ply doublers (tripplers?) I fabricated to go from the LG block back just past the front hardwood wing mount block. I did this because I used aluminum LG instead of the wire stuff supplied with the kit. I ended up putting filler wood in the slots of the supplied fuse doubler where the LG wires were intended to lay, and I wanted additional support for the LG block for torsional support as well as additional support for the front wing block and fuse side at that location.

Timthetoolman1

My Feedback: (6)

Pilgrim, I think my bass stringers should serve the same purpose and add some strength to the fire wall. I'll be laying them up after I install the horizontal stabilizer because I can't get a good measurement with the stringers in place.

I did get the bottom wing within 1/2 degree from horizontal but the high side has a 1mm gap so by the time I get it right there shouldn't be any variation.

Found the landing gear at Stan's (glad I didn't glue the factory mount in yet). I'll also order the cowl and pants, as well as a set of gear for the second bipe, from Stan's. I think if you order it all you get 50% off the gear ~ $14

MinnFlyer

My Feedback: (4)

Two things:

First, Weather you're using that engine or not, I'd get rid of that Exhaust Extension. If you want to divert the exhaust, all you need to do is loosen the header at the engine and the muffler will swing down. Those exhaust extensions can rob you of power.

Second, I rarely will ever mount an engine inverted for two reasons:

1, Sometimes engines have a difficult time starting while inverted

But most of all

2, If you have a nose-over, your Rocker Arm Cover is the first thing to take the abuse!

Timthetoolman1

My Feedback: (6)

Good points. I've never had engine problems inverted and it would hit the spinner and miss the rocker covers (already thought of that). How do you get rid of the exhaust extension and still mount it? Thanks, Tim.

MinnFlyer

My Feedback: (4)

This is the piece I'm referring to:

Timthetoolman1

My Feedback: (6)

Oh, that is from another plane when I had to take apart for gas clean up, it needs it to get out of the cowl. The exhaust on this plane shouldn't need one.

Garthwood

Gn.....................I'm in the process of mounting a Saito 1.20 on the CG Ultimate ARF. I'm mounting it the way they're suggesting, sideways. The engine mount itself is an adjustable mounting, supplied with the ARF. It is not the metal one that they're showing in the instruction manual. It is quite a chore cutting the cowl to fit this size engine. This is probably the best way of mounting the engine. It is easy to reach the glow-plug, you would'nt need an onboard remote starter. I have seen modelers struggling with inverted engines without the onboard remote. On the Saito 1.20 the needle valve location when mounted sideways, the high speed adjustment is from underneath, but an extension (2-56 wire) can be worked out. The slow speed would be on top of the cowl, a tiny hole can be drilled for a small screw driver when adjustment is needed. Underneath the cowl requiers a cutout about three times what's in front for aircooling and air exit. This is a must unless a miniature cooling fan can be installed .......just joking. But really which ever way you install the engine you need cooling. I will post a picture if anybody is interested.

Regards
Charles.

Garthwood

Here's a couple of pictures........ fitting the cowl to the Saito 1.20 could be frustrating, especially the way I tried with the muffler installed. Rough stages of directing the stubby muffler, I still need to adjust the muffler. The cutout area still need work and a final sanding of the sharp cutout. This engine takes quite a bit of room, but should work.[img][/img]

Garthwood

Front shot of Saito 1.20 on CG Ultimate ARF.[img][/img]

Garthwood

This is how far out the cowl the Saito 1.20 sticks out.[img]

Timthetoolman1

My Feedback: (6)

That looks good, with the 1.25 it shouldn't stick out much at all. Could you run the exhaust straight out of the cowl? I might try that and see what it looks like, thanks for the pictures.

Garthwood

reangerman.................here's a picture of the Saito 1.20 with the muffler outside. It was a bit of a hussle, the problem being that the muffler manifold is a bit short. First keep the manifold threaded in the length that you want it, but do not lock the nut. Second insert the cowl in. Third screw on the muffler adjust the angle and lock in both nuts. There's a tab that extends on both sides of the firewall, you'll need to trim that down at the bottom corner. You should be fine.[img][/img]

ropermike2002

My Feedback: (1)

One other option that is not mentioned here is halfway between inverted and sideways! I mounted the engine in this skybolt that way and really like it! The glow plug is easy to access with my glow starter, the muffler will take the brunt of a noseover, all oil is emitted to the bottom of the plane, and with a smoke system installed, the smoke blows out of the bottom of the plane and is more scale like....I am also planning to build an Ultimate, so all your threads are very helpfull........Thanks, Mike

Garthwood

That looks great Mike........................good luck with your future Ultimate. I opted in buying the ARF for the simple reason that I was building a 1/6th scale Waco YMF -3 Bi-plane. It has 4 flights on it and was completed in 2005. So building two bi-planes was too much. here's a picture of it.[img][/img]. Engine is the Saito .91 4/s. flies like a dream, very scale like, but it is not an Ultimate. The rolls are more like barrel rolls. It is though a very nice scale bi-plane. I left out the wheel pants on this one, I fly off a grass field.

Charles.