Rudolph Hart

All i'm getting 9000 on the ground with a 182 and 18x6 mas prop lots of blue smoke at any transition stage revs seem a bit much tho,saito says 10 max

Hobbsy

My Feedback: (102)

I would be happy with that.

w8ye

My Feedback: (16)

There's nothing wrong with 9000 rpm with a 18 X 6

I use a 16 X 8 on mine. It runs good but I couldn't tell you what RPM its running?

Rudolph Hart

Thanks for the replies.My main aim is to tune it right from the low end too.The airbleed screws are very sensitive it seems.

Hobbsy

My Feedback: (102)

OF, start with each airbleed trim halfway across the inlet hole, you won't have to go far from there if any.

Rudolph Hart

Thanks i'll try that this arvo

w8ye

My Feedback: (16)

I did like this and it was just a minor touch up from there

Rudolph Hart

Mine has been a bit different and ended up tuning off the right cylinder 1 and a quarter turns out and the left is nearly as good now.I like the alternate firing they do at low rpm like tuning an old 750 ducati vtwin

Rudolph Hart

Yes you are right they are nearly half way out.the right cylinder is one and a quarter turns out from factory setting.

bpenner697

My Feedback: (5)

This has probably been asked before but I searched and couldn't find anything??

I have a P51 60 TF and putting a saito fa100 in it. I am debating 4blade vs 2 blade. I have flown quite a bit, but see most posters say you won't get the performance out of a 4blade.

If 5 or 10 mph is what people are talking about as far as performance I would rather have the scale appearance. Not having flown either I would really like some advice. Does it make a big difference for stall recovery or torque on take offs...those are the performance things I would really be concerned with.

I am thinking 13x6 for a 4blade...can you also confirm this would be ok. I also see that the 4blades will run quite a bit more ($30+) than a 2blade, so that is something I am already considering.

Thank you in advance, Brian.

PS - I will also be using a OS125 4 stroke in a warbird and will be considering the same thing for it. 15x6 4blade

w8ye

My Feedback: (16)

The 125 should use a 14 X 6 four blade if you can find one

energyman

My Feedback: (2)

I am in the process of replacing the bearings in the club trainer Saito 65 and cannot remove the rear bearing, even with heat. I read your description of the tool you made but cannot quite put it together how it works and fits. A picture or more detailed explanation would be appreaciated. Thanks.

Danny Jackson

w8ye

My Feedback: (16)

I had an old bad bearing the other day that wouldn't shake out when heated to 325F

While still hot, I took a 3/8" steel rod and drove it out the back from the front end with a small hammer

I had done the same thing to the front bearing by sticking the rod through the center of the rear bearing and against the front bearing. I slammed the rod and crankcase against a big board and the rod sent the front bearing flying.

Craig 01

Rear bearings that have a build up of crud/varnish between the radius of outer race and case can help make bearing removal difficult especially when heated before removal of said crud.I will soak those engine crankcases affected in petrol overnight and scrub with a stiff nylon brush to remove remaining residue then wash in hot soapy water, rinse and dry.
I use a propane torch for most bearing changes to expand the case and most times the bearing will drop under its own weight,if not,a quick rap on a block of wood every few seconds while heating using leather gloved hand will have the bugga out.The bearing will move when the case has expanded sufficiently when using this method.
I have had to use a drift on front bearings but usually only requiring a couple of light taps with the drift from behind once the case is heated sufficiently.

Rudolph Hart

I think craig is right slow heating does not take advantage of the aluminiums rapid expansion rate to enable the necessary pop and bearing removal ease.

Rudolph Hart

If you want less revs a 15x8 will load it up.Since a one bladed prop is the most efficient one just downgrade your power and it's delivery expectations compared to a 2 blade and happy flying

Hobbsy

My Feedback: (102)

B, that old wives tale about more blades= ineffeciency went out the window a long time ago, since the blades are constantly moving forward into new undisturbed air, no loss of effeciency. Were you looking at these?

http://www.zingerpropeller.com/4_bladed_propeller.htm These are high quality and Joe gets them to you quickly.

blw

My Feedback: (3)

An argument could be made that the one bladed prop is one of the most inefficient......

FNQFLYER

With regards to the rear bearing removal on the 65.  Having recently done one (with difficulty)  here is what I did.
1/ I copied my mates bearing extraction tool which is a modified 5/16th (or might be 3/8th) right angled key by grinding the short end until I had a flat blade formed about 1/8th thick (you'll have to experiment a bit) 
2/ This is then fed in from the front and "engaged on the lip of the rear bearing and is then the tool is hit with a hammer moving the tool around the bearing until it moves away from the face of crank shaft.  Be careful as the lip at this stage is only small as the bearing moves the gap widens and you can move the tool into the gap sidewas getting a better purchase and of course more force (as required) can be applied.
While all this is happening I keep the whole job warm / hot with my covering heat shrink gun (hair dryer), if all else fails here I go to the kitchen and use the oven heating every thing up to about 300 degrees F   I find welders gloves very handy at this point.
3/ To remove the front bearing I usually use a 3/8 hard wood dowel and a bit of localised heat, works wonders.
4/ For removal drifts I find concrete re inforcing steel rod is a good starting point if I don't have any surplus allen keys, phillips screw driers are also ok as all with stand the heat some times applied to them

BTB the tool mentioned above was manufactured from a diagram from the little red Saito book out of the RCM library I keep on talking about
  

FNQFLYER

On props 4 blade props can be used for 2 things in full sized a/c. 
1/ To absorb shaft horsepower, eg Alison 501 /T34  (L188 or P3), or in big radials eg Rare Bear and the P&W 4350 
2/ To generate more grunt eg Rare Bear and the P&W 4350.

Compare the standard prop on a Mustang with the Reno ones.  Yes some have Griffons but even the hotted up Merlins use 4 Bladers.

In model comps the type of prop is dependant on performance required as opposed to what the engine will turn within the parameters you desire.  EG my design and manufacturered by Bolly 12.5 x 5.5  2 blade carbon fibre (with a specific twist) were heaps better than his similar sized clubman series etc.

What I am trying to say is that without the necessary computer power one cannot say what prop is better than another except by experimenting.

energyman

My Feedback: (2)

I was able to get it out by using a deep well socket that would just fit through the front of the crankcase and then pressed the bearing out by placing the whole contraption in a vise and slowly turned the handle. Worked like a charm. Thanks for all the replies. New bearings orded fromR/C Bearings.

Energyman

w8ye

My Feedback: (16)

Good job

I've done it that way also. Works nice

Craig 01

Good to hear you sorted your problem,if all else fails use brute force

Tarasdad

Pressing and pulling is how bearings on high-performance motorcycle engines are replaced. Been there, done that too many times (used to be a motorcycle mechanic).

Rudolph Hart

Hello guys and good Lord those 182's have a nice crackle on half throttle fly byes,lightens my wallet when i think how a 300 would sound