What readily available wood prop is best for this engine? I've used the APC 11.5 x 4 exclusively on my .46's forever. I need to remove some weight from the nose and I figure a wood prop would be the best way to go. I've added about 1.5 ounces to the tail already.

Perry
I never found a wood prop I was happy with when I was flying LA's and once we discovered the Thunder Power props. That was the best prop and the golden ticket IMHO.

A Xoar prop might be worth a try.

https://www.ebay.com/itm/227311341495?_skw=xoar+pja+11x5&itmmeta=01KX649QV8G1PKVDE732BFQJCR&hash=item34eccfcfb7:g:f8IAAeSwfLxp6BLw&itmprp=enc%3AAQALAAAA8GfYFPkwiKCW4ZNSs2u11xA%2F8V4%2FLUnEh8tQ4QXQvtn0F7839sv41edQ27K%2F15yxnWJlZvPqtBdHwibOyq953tg97dh%2FuhEdSfZZxQzQpwFZul1CJCCywnbPR7TjsZn0rgxd1KABEB0FhqEVN1PQFXvHKVoC%2Fdo0NAIUR6HGvNxECJGv7Z9XBvFYiCEdPzVugp%2BhQQcL75s93l85HvwZnQqJF1dQpTp4pdRw0GIdR%2BIrlQ6uw7BATuNrcs5CspPvZ9TIYHxpLaqGPX%2FLGC51uaMlfCJ8luaaEpGV8brzn4k%2BdNMiy7h79l4wL5qTKnkqbQ%3D%3D%7Ctkp%3ABk9SR-r9psTpZw

  I had a Brodak .40 in a ARF Nobler that I used the APC prop and the magic Thunder Tiger 11-4.5 ( I think) that everybody liked to the B-.40 and the .LA.46 but had the same issue that you have, needed a better turn but didn't want to add more tail weight. So I copied the Thunder Tiger props in wood using one of those Rev-Up 12-5 drone props that have been turning up for years as a blank to start with, and by matching the blade shape and thinning the wood blade to match the TT prop, it came out almost an ounce lighter than the TT prop weighed. I put up some flights to accurately check take off RPM, measured the fuel load carefully, recorded the run time and lap times as a reference. Then I just changed props, nothing else. Take of RPM Was the same almost exactly. Run time and lap times were within a whisker of each other, and I got the turn I was looking for!! I have a theory that it's the blade shape and the thickness that makes the TT prop work so well. I detailed in a thread here on Stunthanger also. I remember seeing posted also that some guys were using the Rev-Up 12-5 drone props cut down to 11 and 11.5 with good results also. As the props sits, it's probably closer to 4 inch pitch. If you can find any of those or any Rev-Up 11 and 12 inch props that you can modify, it doesn't take very long. I would also consider the Xoar props also in the 11-4 and 11-5 range, and maybe start with a 12 inch prop and cut down. let us know what you use and the results you get.
  Type at you later,
   Dan McEntee

I have a Vector 40 model w/ OS 46 LA engine that is quite heavy at 62 oz. I acquired the model already built and had no control over the final weight.

I have tried a bunch of different props and settled in on a BY&O 12-3 wood prop (from Brodak) for my model (at 10,000 rpm on the ground). I was quite surprised that it would even work out due to the low pitch, but it does. The BY&O prop design has a very wide airfoil. I believe the combination of a wide low-pitch prop spinning fast was best to pull my heavy model.   

Colin

Thanks guys.

The Master 12x5 scimitar has been a good one for me on the LA .46.  Might be a bit lighter than the  APC.

We've found the LA .46 doesn't 'have to' run as fast and hard os say the FP .40 etc. with a low pitch prop.  It has some cycle break capability with more pitch.  We have one here flying well with the old Tigre .46 fav RevUp 11 1/2x 6.  These are harder to find but you might try 11x6 and open your needle a bit.  Even the old Top Flite 11x6 Power Prop seems to work.

Dave

Quote from: Dave_Trible on July 11, 2026, 05:02:46 AMWe've found the LA .46 doesn't 'have to' run as fast and hard os say the FP .40 etc. with a low pitch prop.  It has some cycle break capability with more pitch.  We have one here flying well with the old Tigre .46 fav RevUp 11 1/2x 6.  These are harder to find but you might try 11x6 and open your needle a bit.  Even the old Top Flite 11x6 Power Prop seems to work.

Dave

Dave

I realize that the 46 LA doesn't have to necessarily spin fast to work out in general.

I had a past separate post specifically discussing my 'heavy' Vector 40 (wing loading at 16.7) and suitable props to try. Brett was helpful and offered the suggestion that low pitch and high rpm was the solution to my model weight issue (i.e.: best chance of success). I had tried various props all with a 4 pitch. Even the APC 12.25-3.75. Then I came across the fat blade BY&O 12-3 and gave it a try. It just pulls my model better IMO. And I'm not running the 46 LA outside of what it was designed for. Per the OS owner's manual, I find peak rpm then richen say 20-30 degrees on the needle as I notice the rpm droop a little. That's about 10k on the ground on 10 nitro VP fuel for the BY&O 12-3 prop.

Colin

Quote from: Dave_Trible on July 11, 2026, 05:02:46 AMWe've found the LA .46 doesn't 'have to' run as fast and hard os say the FP .40 etc. with a low pitch prop.  It has some cycle break capability with more pitch.  We have one here flying well with the old Tigre .46 fav RevUp 11 1/2x 6.  These are harder to find but you might try 11x6 and open your needle a bit.  Even the old Top Flite 11x6 Power Prop seems to work.

Dave

    The Top Flite Power Prop has the same shape that the Thunder Tiger "magic" props have, ( or the Thunder Tiger "magic" prop has the same shape as the Power prop!)and I pick those up any time I run across them cheap. In checking ads in old magazines it seems that Top Flite didn't make them for very long and I wonder why?  They do work pretty well when I have tried them.

  Type at you later,
  Dan McEntee

Quote from: Dan McEntee on July 11, 2026, 07:19:34 AMThe Top Flite Power Prop has the same shape that the Thunder Tiger "magic" props have, ( or the Thunder Tiger "magic" prop has the same shape as the Power prop!)and I pick those up any time I run across them cheap. In checking ads in old magazines it seems that Top Flite didn't make them for very long and I wonder why?  They do work pretty well when I have tried them.

  Type at you later,
  Dan McEntee

As I'm thinking about it I think we have taken the 12-6 Power Prop and trimmed it to 11 1/2" with good luck .  I believe that's what was on my son in laws' profile at the Nats.  I yields a little more blade area.  While these props are no longer made,  they will turn up on Ebay here and there...just keep looking.

Dave

I may have posted this before, but it seems relevant. The weight differences can be pretty dramatic. The inertia differences are too. This is one reason that you don't run a heavy plastic prop on an old engine with a weak crankshaft--like a Fox .35 Stunt.

Quote from: Dave Hull on July 11, 2026, 02:12:19 PMI may have posted this before, but it seems relevant. The weight differences can be pretty dramatic. The inertia differences are too. This is one reason that you don't run a heavy plastic prop on an old engine with a weak crankshaft--like a Fox .35 Stunt.

    I've seen the APC Prop/Fox .35 crank shaft breaking syndrome!! A guy here likes the APC 10-6, and likes to run a Higley heavy hub for balance on his Barnstormer and I think he's broken two cranks that I can remember!! As long as I have been flying stunt semi seriously, I have always wondered if a heavy prop made any difference in how an engine ran, and can't think of any time where I saw evidence one way or the other, until I made that first Thunder Tiger prop copy, and was able to get tach readings back to back flights within ten minutes of each other, and experienced no difference. Is the one ounce difference enough to influence an engine on how it runs and performs? I guess that is the question here. The above mentioned APC prop/Higley heavy hub didn't appear to affect the run on that engine, other than breaking the crankshaft!! Maybe most of the weight of a heavy plastic prop is in the hub and the root  of each blade, and being that close to the cranks shaft centerline negates any type of flywheel affects??  I like the APC props, though, when I can stand the weight in the nose of an airplane, but that tends to not happen much in my experience.
   Type at you later,
    Dan McEntee

  PS: I like the Xoar prop also, and have noticed the green dot on the hub sometimes. Hav you got any idea what they use for the balance weight? Just curious.

Weight on any engine will delay the 4-2 break because the engine needs to accelerate the weight to change rpm. This also adds stress to the crankshaft which can cause the breakage. Best to use the lightest prop possible and add weight to the nose in the fuse for balance or add a heavier muffler if you need a lot of weight then trim with weight in the fuse. You can use the heavy hub to get an idea of how much nose weight you need then put that amount in the fuse/muffler.

Best,   DennisT

Quote from: Dennis Toth on July 12, 2026, 08:16:40 AMWeight on any engine will delay the 4-2 break because the engine needs to accelerate the weight to change rpm. This also adds stress to the crankshaft which can cause the breakage. Best to use the lightest prop possible and add weight to the nose in the fuse for balance or add a heavier muffler if you need a lot of weight then trim with weight in the fuse. You can use the heavy hub to get an idea of how much nose weight you need then put that amount in the fuse/muffler.

Best,   DennisT

    Well, I know all of that. Fox .35 cranks can break all by themselves without any help and it's a long time known flaw of the engine, but gets aggravated by a heavy hub. The weight in addition to stress from gyro effect has a part in it. If you never do a loop or a square corner, you might not ever break one.  I've had it happen to me when just using a Top Flight butter blade prop!! But that engine had a LOT of time on it. It's never changed how an engine runs for me as far as I can tell. As I mentioned, the weight is centered pretty close to the crank shaft center, so if you WANT to add weight and have it affect the run, it needs to be out further from the center. That's why you try a bigger diameter prop on a model if you are trying to trim out a hunting tendency. Weighted cutch arms in things like R/C helicopter clutches, (if they still use those for gas powered helis) R/C car clutches for gas powered R/C cars (if they still use those) and for adjusting clutches on racing go kart engines is another example. You want those as large a diameter as you can get them so weight changes have a better effect. When you have a two stroke motorcycle engine that you want to make better power and traction  in lower RPM ranges and take advantage of available torque, you put a large diameter heavy flywheel on it, and there are some available that you can change the weights on. If you want the opposite, you go smaller diameter, most often an internal rotor,( you really can't call it a fly wheel ) that spins inside the ignition coils. When it comes to the time an engine makes it 2-4 break, a heavy prop, and I think it needs to be substantially heavier to have any noticeable effect, it will maybe slow it down or smooth out an abrupt break, but I think it needs to be substantially more that just the one ounce or so that we typically see that is spread out over the entire length of the prop, but the majority of it is near the center. But the accumulated weight of the prop, still affect the balance of the airplane.
  Type at you later,
  Dan McEntee

Quote from: Motorman on July 10, 2026, 06:45:23 AMhttps://www.ebay.com/itm/227311341495?_skw=xoar+pja+11x5&itmmeta=01KX649QV8G1PKVDE732BFQJCR&hash=item34eccfcfb7:g:f8IAAeSwfLxp6BLw&itmprp=enc%3AAQALAAAA8GfYFPkwiKCW4ZNSs2u11xA%2F8V4%2FLUnEh8tQ4QXQvtn0F7839sv41edQ27K%2F15yxnWJlZvPqtBdHwibOyq953tg97dh%2FuhEdSfZZxQzQpwFZul1CJCCywnbPR7TjsZn0rgxd1KABEB0FhqEVN1PQFXvHKVoC%2Fdo0NAIUR6HGvNxECJGv7Z9XBvFYiCEdPzVugp%2BhQQcL75s93l85HvwZnQqJF1dQpTp4pdRw0GIdR%2BIrlQ6uw7BATuNrcs5CspPvZ9TIYHxpLaqGPX%2FLGC51uaMlfCJ8luaaEpGV8brzn4k%2BdNMiy7h79l4wL5qTKnkqbQ%3D%3D%7Ctkp%3ABk9SR-r9psTpZw

Make sure you get the 3 year protection plan from Allstate for only $2.99 extra! I think it would be hilarious to submit a claim and see what happens. Personally, I'd try the Xoar 12-4, but might pitch up the tips a little and trim the diameter as needed. Probably would violate the Allstate warranty?  Steve

Quote from: Perry Rose on July 10, 2026, 06:30:16 AMWhat readily available wood prop is best for this engine? I've used the APC 11.5 x 4 exclusively on my .46's forever. I need to remove some weight from the nose and I figure a wood prop would be the best way to go. I've added about 1.5 ounces to the tail already.

  There well may be lighter props that are just as good or better, if you can find them. But - and I can't emphasize this enough - you cannot compromise the engine performance to try to save even a tiny bit of weight, and you can't compromise the trim to save weight. That is, if you find a heavier prop that works better, use that prop, use as much lead as necessary to balance the airplane properly.

    Brett

Slightly nose heavy, better than slightly tail heavy as far as total weight added is concerned. Is there any way to move the engine back?

I have a fondness for the Xoar 12x4 for the LA .46.....set the needle just rich enough that I get a noticeable RPM rise when I hold the nose straight up before take off.

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