Apc props and the Nelson LS Q40 motor  
View related threads: (in this forum | in all forums)

Tower Hobbies
Enter up to 4 keywords or Tower stock numbers
Logged in as Guest



Users viewing this topic: none
  Printable Version
       

All Forums >> RC Airplanes >> Pylon Universe - RC Pylon Racing >> QM-40 Racing >> Apc props and the Nelson LS Q40 motor
Page: [1] 2   next >   >>  

Login
Message << Older Topic   Newer Topic >>
Apc props and the Nelson LS Q40 motor - 2/24/2007 9:34:41 PM   
Ed Smith


 

Posts: 2834
Joined: 12/29/2001
From: Brantford, ON, CANADA
Status: offline 		Am I hearing wild rumours or is it true that the new Approved APC carbon props are coming apart on the new Nelson LS Q40 motor?

Ed S
       Post #: 1

RE: Apc props and the Nelson LS Q40 motor - 2/24/2007 11:40:45 PM   
ALbert.S


 

Posts: 197
Joined: 7/13/2002
From: Roseville, MN, USA
Status: online 		Yes The word I got is they lost 7 this morning and had a meeting on what to do

(in reply to Ed Smith)
       Post #: 2

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 12:19:28 AM   
HighPlains


 

Posts: 2663
Joined: 3/2/2003
From: Over da rainbow, KS, USA
Status: offline 		So perhaps springing a new engine on the racing community along with new untested props 10 days before a large race was not the altruistic act it was made out to be. Though I think that this was timed to achieve a competitive advantage for a few, who was the benefactor?

I just hope nobody was injured.

_____________________________

In politics if you want anything said, ask a man. If you want anything done, ask a woman - Margaret Thatcher

(in reply to ALbert.S)
       Post #: 3

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 1:10:48 AM   
SCPYLONRACER


 

Posts: 84
Joined: 12/25/2004
From: , SC, USA
Status: offline 		After the first day in Phoenix there is a new record 59.24 by Matias Salar

Standing as of end of racing on Saturday.

1st Matias Salar
2nd Dave Shadel
3rd Grunk

(in reply to HighPlains)
       Post #: 4

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 3:54:25 AM   
PylonDave



Posts: 201
Joined: 5/8/2006
From: rancho cucamonga, CA, USA
Status: offline 		is everybody ok???

< Message edited by PylonDave -- 2/25/2007 4:17:31 AM >

(in reply to SCPYLONRACER)
       Post #: 5

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 3:59:24 AM   
Bill Vargas



Posts: 1554
Joined: 1/6/2002
From: Team Coldies, CA, USA
Status: offline
quote:

ORIGINAL: HighPlains

So perhaps springing a new engine on the racing community along with new untested props 10 days before a large race was not the altruistic act it was made out to be. Though I think that this was timed to achieve a competitive advantage for a few, who was the benefactor?

I just hope nobody was injured.


Pylon Racers abroad, lets not beat up on Fred. I know for a fact that any new prop that comes along is thoroughly checked out by the Contest Board before its release to the public. Fred has done an awful amount of work to keep us happy with these black props,,,

IF it wasn t for these black props, you and I would be carving our own.

I am sure once Fred concludes his investigation, he'll have a fix.

I've blown tips off before,,, and since then I've learned to Pre-Flight the Prop Before the next Flight.


BV

< Message edited by Bill Vargas -- 2/25/2007 5:44:56 AM >

_____________________________

If it ain't leaking oil, then something's wrong,,, USMC, RETIRED!

(in reply to HighPlains)
       Post #: 6

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 4:53:39 AM   
js3



Posts: 1142
Joined: 1/30/2002
From: Arvada, CO, USA
Status: offline 		Three questions:

1) Were the props that came apart all run on the LS Nelson or were some run on the old version?

2) Were there failures on the Jetts?

3) Did any of the older props fail and on what motors?

_____________________________

John
I feel a lot more like I do now than I did earlier!

(in reply to Bill Vargas)
       Post #: 7

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 4:57:05 AM   
Bill Vargas



Posts: 1554
Joined: 1/6/2002
From: Team Coldies, CA, USA
Status: offline 		Incase your wanting to know what these props are doing,,, its kinda looks like this. I found this right after one of my post flight inspections a while back.

This was a second generation 7.4 x 8.0, right after the 7.4 x 8 ran dry, on last years Q40 Nelson engine model.

So pay attention to detail,,, your planes life is depending on it


BV

Attachments
Click to see fullsize image.
Click for fullsize


< Message edited by Bill Vargas -- 2/25/2007 5:47:00 AM >

_____________________________

If it ain't leaking oil, then something's wrong,,, USMC, RETIRED!

(in reply to Bill Vargas)
       Post #: 8

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 6:24:26 AM   
Tony Pacini


 

Posts: 265
Joined: 1/11/2002
From: Prescott Valley, AZ, USA
Status: offline 		Everybody's OK, that I'm sure of. There have been no injuries.

All the failures that I've heard of have been with those using the new LS engine. Airframes seem to be a contributing factor.

I have not heard of any failures on the Jetts.

The facts will come out after the race is over. The majority of the contest board is at the race, as are Fred from APC and Dave from Performance Specialties. We'll see what happens tomorrow................





< Message edited by Tony Pacini -- 2/25/2007 6:25:35 AM >

(in reply to Bill Vargas)
       Post #: 9

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 6:44:27 AM   
Terryoc


 

Posts: 88
Joined: 6/19/2002
From: WerribeeVictoria, AUSTRALIA
Status: offline 		Some time ago this problem surfaced in F3D when engine performance of the Longer stroke motors ( Rossi/Phelan and MB) got to a certain level , I think the main fix for it was a longer conrod so that it smoothed out the power pulses from the motor. So I wouldnt jump on the props to quick.
Terry

(in reply to Tony Pacini)
       Post #: 10

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 7:18:01 AM   
PylonDave



Posts: 201
Joined: 5/8/2006
From: rancho cucamonga, CA, USA
Status: offline 		are they failing in the air or on the ground???

(in reply to Terryoc)
       Post #: 11

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 12:31:41 PM   
Ed Smith


 

Posts: 2834
Joined: 12/29/2001
From: Brantford, ON, CANADA
Status: offline
quote:

Pylon Racers abroad, lets not beat up on Fred. I know for a fact that any new prop that comes along is thoroughly checked out by the Contest Board before its release to the public.


Come on now Bill, How were they checked? Obviously not properly.

I had a long discussion with Gary S a while ago and how the new props were rushed into use. Now we know why. They were rushed through to coincide with the release of a new engine. An engine that only a select few knew about 10 days before a major contest!

A number of airplanes were lost because of the problem. This is a minor consideration if we consider the potential injuries to people that could have happened. Thankfully there were none.

Ed S

(in reply to Bill Vargas)
       Post #: 12

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 3:12:41 PM   
Ed Smith


 

Posts: 2834
Joined: 12/29/2001
From: Brantford, ON, CANADA
Status: offline 		It would appear that Q40 racing is in for a major upheaval. A post on the NMPRA site hints that APC will not make anymore carbon props for Q40 racing. If this is the case then we will be back to woodcarving, IF we can find suitable blanks. The other alternative would be to allow the use of carbon/epoxy continous strand props. I understand the arguments against this. Some of us have the expertise and proven track records in the production of this style of prop. However, others while going through the learning process could create some real monsters.

There will be a lot of discussion I am sure. The important thing is that we all make our feelins known in a clear and constructive manner. We should try and ensure that whatever decisions are made serve the whole racing community and not just a select few.

Ed S

(in reply to Ed Smith)
       Post #: 13

RE: Apc props and the Nelson LS Q40 motor - 2/25/2007 10:08:57 PM   
bigtrev@xtra.co.nz


 

Posts: 251
Joined: 9/25/2004
From: christchurch, NEW ZEALAND
Status: offline 		Terry, fully agree with your comments, we had the same problem here in NZ with F3d..........about the time you are talking about. Changed a few things, one the engine as you describe, and the other was the layup I ued then of the carbon. I was loosing 22mm off the blade, but always the blade toward TDC. Maynot be the same problem but certainly not too dissimilar, trevor H

(in reply to Terryoc)
       Post #: 14

RE: Apc props and the Nelson LS Q40 motor - 2/26/2007 12:49:09 AM   
Tony Pacini


 

Posts: 265
Joined: 1/11/2002
From: Prescott Valley, AZ, USA
Status: offline 		Hand-laid carbon props would certainly solve the safety issue. There are even commercially available sizes that would work.

Safety, though, is not our only issue.

We've been spoiled by the availability of a consistent and readily available $10 APC prop for Q-40.

Wood props have been coming apart, too, with the new LS engines. Very few were using wood, so the limited number of failures does not necessarily indicate that there isn't as much of a problem with wood as there appears to be with the APCs.

If the rule changes to "wood only", participation will surely drop and we may be no safer. If the rule changes to hand-laid carbon, price will certainly go up and availability will suffer. There is no easy answer.

Airframes also appear to be a contributing factor, but those assumptions may be skewed by the fact that certain airframes are more common than others.

We had yet another failure this morning with a 7.4 x 7.8, only this time it was on an airframe that hadn't yet experienced a failure. The tip of the blade came right off. Again, luckily, no one was hurt.

The dust hasn't settled yet. I would guess that the failed props will be analyzed and a solution will be proposed. What happens in the meantime we can only guess.........

But let's not get too upset about this until the facts are known and the solution is proposed. Nobody meant for this to happen.



(in reply to bigtrev@xtra.co.nz)
       Post #: 15

RE: Apc props and the Nelson LS Q40 motor - 2/26/2007 1:43:18 AM   
Terryoc


 

Posts: 88
Joined: 6/19/2002
From: WerribeeVictoria, AUSTRALIA
Status: offline 		Hand laid carbon may NOT solve the problem as with F3D they were all hand layed up props with continuous filament.
Some lost tips others lost complete blades, I was using props with spinners molded in at the time and it was ripping the blade out from the hub or at least starting to.
Making one area stonger may only make another area weaker.
The props were never a problem before so you should look at why there are now and its not the prop
We used to use only the glass filled APC here I think they were the D5 on QM 40 engines with no problems then some one modified an MDS 46 which is allowed in our rules and was lucky to get 2 flights to a prop , so for safety they made the props open but full carbon continuous filament and made it mini F3D going from $10 a prop to $40.
Terry

(in reply to Tony Pacini)
  <