Laser 160 inline twin

[Paul De Tourtoulon]

Mike how can you sleep at night after posting you porn videos,,?

 

So maybe one coming my way when Jon gets his production line up, then I can also order 'another' Spitfire,,,

[mike skingle]

Paul you may not like this but here's some more videos. 

An intermittent fault with one of the remote glow plugs and a reciever have caused a few false starts, but it has caused me to ground run the engine a few times and the good news is no overheating problems even after a 10 minute 30seconds run that's with an abiet 16°C. We'll have to wait until the summer to see if the warmer weather is a problem. 

 

Ron I will measure the CG but I wanted to see how it flies with the change in battery position before measuring it. 

It flies great but see is believing. 

[mike skingle]

[mike skingle]

[mike skingle]

[mike skingle]

[Paul De Tourtoulon]

Hi, Mike, you can be so obnoxious, after spending 15 minutes loading and watching your porn videos I was wondering whether the engine could be fitted with a throttle servo for a half throttle flypast, and at the last minute you actually did one,,,

 

One step nearer,,,,

 

 Thanks for the videos,,,

[Jon H]

Sounds great Mike. If you are running the 16x8 still you might want to up the ante and fit 17x8 next time round. 17x8 is the prop i would recommend for warbird flying once the engine has had some run in time, which it now has. 

 

I would expect high 7000's, maybe low 8's on a 17x8 apc so a good 1000rpm down on what i assume is a 16x8. This should give more thrust overall which will be ideal ? 

 

Generally though it all looks awesome, although i was yelling at the screen 'it needs right rudder trim!' but didnt get any reply ?

[mike skingle]

Jon full right rudder trim had been applied to try and straighten the rudder, not sure how it came about, it was straight when setup in the workshop but when it was taken out  at the field the rudder was slightly off to the left so I will investigate and get back to you but looking inside the fuselage it looks like the guide for the snake has bowed not sure why.

I have a 17x8 so I'll try it next time, it might not be an APC though.

 

The pilot in question was very restrained on the first flights apart from a short burst of full throttle most of the rest of the flights were at no more than 2/3 throttle. There didn't seem to be any problems overheating and ground runs have shown no overheating. The engine also has had a reasonable running in period so it was time to see if the cooling was sufficient at higher throttle settings (which it was) and see what it can do, but most of all it was about having lots of fun as we probably won't have weather like that again any time soon, with a plane that looks and sounds great.? still grinning ? 

If you have any specific requests then we'll see what we can do. ?

 

[Jon H]

Ah, bendy snakes are never helpful ? 

 

On the prop, if you have another brand that is decent quality then thats fine, just avoid master airscrew. I have used the apc before so its just a known quantity in terms of its performance. 

[mike skingle]

I have an Aerodrive 17x8 wooden prop otherwise it would be a G sonic 18x8 or 16x10. Or a beila 16x8 4 blade ?

I found that the support for the rudder snake had come unglued from the fuselage andwas now wedged further down the fuselage hence the change in rudder trim. 

[Jon H]

The gsonic props might be interesting. 18x8 especially. If it does 7500 or more then i would try one of those as well. Just see what works best

[mike skingle]

Hi Ron

I've checked the CG and its slightly forward of 137mm at around 130mm when measured from the leading edge at the centre of the wing. It needs a little back pressure on the stick, so 137mm is probably right not 157mm.

If you're building it from the kit then I would suggest that you consider putting either or both the rudder and elevator servos in the tail as I have 2 large lipos and the fuselage servos towards the back of the wing and it's still needs more weight towards the tail.

[Ron Gray]

Great info Mike, thanks. Looks like I may well start this after Christmas so timely post!

[Aldo Rebsamen]

Hello dear User of the inline 160

 

I like the inline 160 and its sound. 

It makes me thinking of building a Yak3 from Jerry Bates plans. The small one. I still have a shortkit.

Scale: 1/5.3
Wingspan: 68”
Length: 63.5”
Weight: 15 – 18 lbs
Engine Size: 1.08 – 1.4 2-Stroke 

 

Do you think the 160 inline will be OK for the Yak?

Or ist it too heavy for the small wing?

Therefore a 155 would be the better choice.

Are there any adapters for the propeller-shaft available? So the engine can move further inside the cowl.

 

Thanks for your advice.

Aldo

 

Makeover of a Seagull Yak3u 63" is nearing completion. Power will be a Laser 150 of older design.

 

 

Edited December 6, 2021 by Aldo Rebsamen

[Jon H]

The bates Yak3 should work well with a 160i. The whole front end of the fuselage will need modifying as with everything using the inline but it should be ok.

 

Post up a photo of the fuselage plan if you can just so we can take a look

Edited December 7, 2021 by Jon - Laser Engines

[Aldo Rebsamen]

Hello Jon,

that sounds good. Here is the plan:

 

Regards Aldo

 

How much is the weight of the 160i ?

 

 

Edited December 7, 2021 by Aldo Rebsamen

[Jon H]

Weight is around 2kg. Looking at the drawing you will need to mount the engine to former F5 i would guess. The engine is 230mm long so you can measure it out. 

 

Getting the cooling air over the wing and out of the scale radiator looks pretty simple though and the fuel tanks will probably sit on top of the wing

[Ron Gray]

Well I've started (eventually) my rework of my P51 to take the 160 in line twin, starting with cutting off the existing bulkhead and recessing the new one back 60mm.

 

Good old floorboard saw in use!

 

 

 

 

Plywood location pads epoxied in place, the whole lot will be glassed both front and back. Magnets used to hold them in place until dry.

 

 

@mike skingle did you look at baffling the cowl so that the hot air exits through the exhaust ports (starboard)? in other words the air moves from left to right across the engine.

Edited February 26, 2022 by Ron Gray

[Jon H]

Thats what im talking about. Proper tools and no messing about 

[Ron Gray]

What do you think about the idea of using the exhaust port to extract the hot cowl air Jon?

[mike skingle]

Hi Ron

On my mustang the air enters through the chin intake gets forced to the lower left side (as you look at the model from the front).

 

The air is then forced across to the right side through the engine cylinder heads by the firewall and a baffle stopping the air going over the top over the crank case.

 

The air then exits through a hole in the firewall on the right side.

 

And is ducted out the back of the fuselage.

 

 

At an ambient temperature of 16°C the temperature in the duct is about 40°C.

Currently I am working on modifications to a YT spitfire. 

The air will go in the oil cooler intake and be for to the left lower side of the engine bay and across the cylinders and out through the firewall. The only difference is there will be no ducting and the air will be drawn out of the fuselage through the back of the radiators underneath the wings. The theory is that the radiators will draw the air through the fuselage and the fuselage acting as a duct will slow the airflow so less turbulence near the carburettors but we'll see. 

 

Ron my old yt mustang balanced with no lead and a laser 150.

The added weight of the inline twin means to save adding weight to the tail, mounting the servos in the tail maybe a solution. My test mustang the servos and dual batteries are towards the rear of the wing and I have added weight to the tail to get a better CG balance. It's not been test flown yet though. 

 

[mike skingle]

The exhuast holes in the cowl were and still are blocked by gaffa tape.

I'm not sure if you would get enough draw through the exhausts but its worth a try. If i get the chance I'll try running the engine with the gaffa tape removed and block the duct.

What could possibly go wrong ? 

[GrumpyGnome]

@Ron Gray How will you 'key' the firewall to the shortened fuselage? I'm curious as I may want to shorten the nose on one of my models, and, as originally built, there were multiple locating lugs to firmly lock the firewall in place.....

[Ron Gray]

Thanks for your posts Mike. I know that you duct the hot air back through the fuse but I was thinking that as we are creating a cross flow of air to cool the cylinders the logic would be to allow the hot air to escape through the exhausts. The cutout for the exhaust stubs is quite large so I was thinking that if I use metal mesh I could mount the (hollow) stubs to that which would still give plenty of ‘open’ area plus I’m thinking the the stubs themselves may act to create some negative pressure to help the hot air escape.

 

I may try the idea out on my Sportster in which, at the moment, the air is channeled across the cylinders but down and out of the back of the cowl, putting a Louvre on the ‘hot’ side of the cowl maybe more effective as the air has less distance to travel and is moving in more of a straight line.

 

@GrumpyGnome I will abrade the composite fuse then glass the new bulkhead from both the front and rear (difficult to get behind it but can be done). I’ve experimented with the ply fixing blocks, firstly with no abrasion and then with, there is a big difference between the resultant adhesive (expoxy) strengths.