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Lynn Matteson

Joined: 10 Jan 2006
Posts: 2778
Location: Grass Lake, Michigan

Posted: Tue Feb 17, 2009 11:34 am Post subject: Seasonal change reminder

A reminder to check those wooden props for proper torque values. I  

installed a new Sensenich wood prop on Dec 11th, and on Feb 11th or  

so, I re-checked the torque, and found it was half of the original  

setting of 160 inch-pounds. I had put about 15 hours on the engine.  

This was apparently all due to humidity changes. When I first  

installed the prop, I torqued to 160"-lbs, test flew it for a half- 

hour, and re-checked torque, then planned on another check at the  

next oil change...25-30 hours. What tipped me off was seeing just the  

faintest of faint dust marks around the periphery of the prop-drive  

hub, and on the prop itself at that point. When I wiped it with a  

white cloth, I knew what it was...paint dust from the prop. It had  

apparently been shuckin' and jivin' a little bit, and rubbed some  

paint off. You can bet I'll be checking that damn thing more often  

than just at oil changes from here on out. Maybe it was partly due to  

humidity changes from Florida, where it was built, to Michigan, where  

the humidity is low in the winter.



Lynn Matteson

Kitfox IV Speedster, taildragger

Jabiru 2200, #2062, 605 hrs

Sensenich 62x46

Electroair direct-fire ignition system

New skis done and flying

_________________
Lynn
Kitfox IV-Jabiru 2200
N369LM

n85ae

Joined: 14 Mar 2007
Posts: 403

Posted: Wed Feb 18, 2009 7:23 am Post subject: Re: Seasonal change reminder

Mine stays pretty constant after 5 years. The wood compressed a bit the first year or so but rechecks fine now. I check every 50 hours. I also have 

a Sensenich.



Located near Chicago, so pretty much same weather you have over

in Mich.



Jeff

Lynn Matteson

Joined: 10 Jan 2006
Posts: 2778
Location: Grass Lake, Michigan

Posted: Wed Feb 18, 2009 12:30 pm Post subject: Seasonal change reminder

Good to hear, Jeff. I think maybe mine was swollen with humidity  

coming from Florida, then shrank after it arrived.



Lynn Matteson

Kitfox IV Speedster, taildragger

Jabiru 2200, #2062, 605 hrs

Sensenich 62x46

Electroair direct-fire ignition system

New skis done and flying





On Feb 18, 2009, at 10:23 AM, n85ae wrote:



 	  Quote: 	
		   



 Mine stays pretty constant after 5 years. The wood compressed a bit  

 the first year or so but rechecks fine now. I check every 50 hours.  

 I also have

 a Sensenich.



 Located near Chicago, so pretty much same weather you have over

 in Mich.



 Jeff





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p 30827#230827

_________________
Lynn
Kitfox IV-Jabiru 2200
N369LM

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Wed Feb 18, 2009 3:10 pm Post subject: Seasonal change reminder

Are you guys using lock wire on your prop bolts?  When I got my Ivo I called

to see if they forgot to drill the heads of the bolts.  I was told they

preferred to not drill the heads because too many people don't like to cut

lockwire and the bolts whould be torque every ten hours (or so) with a

calibrated wrench.  Personally I think the big thing is to make sure your

wrench is calibrated with in an inch Lb. or so of true.  



With me it goes against the grain to see those nude bolt heads sitting there

with no lockwire on them but I do as I'm told and check the torque often.



Now I've got a warp two blade prop to install does anyone know where I can

find the manual?



Noel



--

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

Lynn Matteson

Joined: 10 Jan 2006
Posts: 2778
Location: Grass Lake, Michigan

Posted: Wed Feb 18, 2009 3:25 pm Post subject: Seasonal change reminder

At the rate that I'll be doing torque checks from here on out,  

there's no way that I'd use lockwire. In fact, Sensenich doesn't  

recommend it for their wood props, if I recall correctly. Metal props  

I could see wiring, but not wood. In fact, I need to inquire of  

Sensenich whether or not to back off the torque if it gets too high.  

They say not to loosen to check torque, but they don't say in their  

printed info what to do if the torque checks out too high.



Lynn Matteson

Kitfox IV Speedster, taildragger

Jabiru 2200, #2062, 605 hrs

Sensenich 62x46

Electroair direct-fire ignition system

New skis done and flying





On Feb 18, 2009, at 6:09 PM, Noel Loveys wrote:



 	  Quote: 	
		   



 Are you guys using lock wire on your prop bolts?  When I got my Ivo  

 I called

 to see if they forgot to drill the heads of the bolts.  I was told  

 they

 preferred to not drill the heads because too many people don't like  

 to cut

 lockwire and the bolts whould be torque every ten hours (or so) with a

 calibrated wrench.  Personally I think the big thing is to make  

 sure your

 wrench is calibrated with in an inch Lb. or so of true.



 With me it goes against the grain to see those nude bolt heads  

 sitting there

 with no lockwire on them but I do as I'm told and check the torque  

 often.



 Now I've got a warp two blade prop to install does anyone know  

 where I can

 find the manual?



 Noel

_________________
Lynn
Kitfox IV-Jabiru 2200
N369LM

jcrowder(at)lpbroadband.n
Guest

Posted: Wed Feb 18, 2009 4:01 pm Post subject: Seasonal change reminder

Lynn,

How do you know when it is too high?



Jim Crowder



[quote] --

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Wed Feb 18, 2009 4:59 pm Post subject: Seasonal change reminder

Just out of curiosity what is the beef with lockwire?  The only thing it

guarantees is the bolts won't back off.  That close to the centre of

rotation weight is not a factor at that rpm.  I keep feeling I'm missing

something here.



Noel



--

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

Lynn Matteson

Joined: 10 Jan 2006
Posts: 2778
Location: Grass Lake, Michigan

Posted: Wed Feb 18, 2009 5:04 pm Post subject: Seasonal change reminder

If you have a "bending bar" style, it's easy to tell...but I  

don't...not in the inch-pound size anyway. If you have the "click  

type" it's only possible to set it at the maximum and if it goes  

there without clicking over, it's at that maximum or too high. I like  

to use the inch-pound, as it's newer, but I may start to use the  

bending bar ft-lb wrench, and check at 10-13 ft-lbs, but that's at  

the low end of the scale and I can't be sure of its accuracy at that  

low a setting. I should probably get it calibrated, but how many guys  

do that?



Lynn Matteson

Kitfox IV Speedster, taildragger

Jabiru 2200, #2062, 605 hrs

Sensenich 62x46

Electroair direct-fire ignition system

New skis done and flying





On Feb 18, 2009, at 6:59 PM, Jim Crowder wrote:



[quote] 

 <jcrowder(at)lpbroadband.net>



 Lynn,

 How do you know when it is too high?



 Jim Crowder



> --

_________________
Lynn
Kitfox IV-Jabiru 2200
N369LM

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Wed Feb 18, 2009 5:07 pm Post subject: Seasonal change reminder

Next question: How do you check if the torque is too high?  The only way I

know of is to loosen the bolts and then re-torque them to spec.  If the good

folks at Sensenich have a method to do this without first loosening please

let me know.



If a bolt is too loose then checking the torque is no problem, just torque

it to spec.  I agree with you humidity certainly can change the pinch on a

bolt. Therefore the torque the bolt sees.



One of the things they made us do in our first year of technical school was

to do stress tests on bolts.  Before pulling apart a bolt will actually

noticeably stretch...  It's called necking ( just like in the back seat of

the 68 Mustang ) but the bolt gets noticeably thinner at the point where it

stretches.  Funny thing is I can't remember seeing a nut giveway. 



Noel  



--

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

Lynn Matteson

Joined: 10 Jan 2006
Posts: 2778
Location: Grass Lake, Michigan

Posted: Wed Feb 18, 2009 5:48 pm Post subject: Seasonal change reminder

No beef with it as far as I'm concerned, but you have to remove it  

every time you want to check torque, and it really doesn't do  

anything to hold the torque setting. It just keeps the nuts from  

rotating off the bolts. With a metal prop and no humidity changes to  

consider, the torque check on a metal prop is how many hours?(Actual  

question...I don't know, but I'll bet it is around a 100 hrs) With a  

wooden prop, and humidity changes occurring possibly weekly, removing  

lockwire is a pain in the ass.



You should see the half-assed method Jabiru came up with to insure  

the tightness of their (soft wood) Jabiru-manufactured props...they  

have you stack 6 belleville washers "tow-to-tow" (their educated  

spelling, not mine) and slide them onto the prop bolts, then install  

nylock nuts and them torque to some figure. The idea being that this  

combo of washers, like this:....()()()...will act like a big spring  

and be able to "give and take" with changes in humidity. I was told  

by the local Jab dealer that this was because the Jabiru-made  

props...not Sensenich props FOR a Jabiru...were made from some very  

soft wood found right there in Australia. Good old Jabiru, always  

willing to use crap to get something on the market...have I sold any  

Jabiru engines tonight?....always willing and glad to help. : )



Lynn Matteson

Kitfox IV Speedster, taildragger

Jabiru 2200, #2062, 605 hrs

Sensenich 62x46

Electroair direct-fire ignition system

New skis done and flying

On Feb 18, 2009, at 7:57 PM, Noel Loveys wrote:



[quote] 



 Just out of curiosity what is the beef with lockwire?  The only  

 thing it

 guarantees is the bolts won't back off.  That close to the centre of

 rotation weight is not a factor at that rpm.  I keep feeling I'm  

 missing

 something here.



 Noel



 --

_________________
Lynn
Kitfox IV-Jabiru 2200
N369LM

Lynn Matteson

Joined: 10 Jan 2006
Posts: 2778
Location: Grass Lake, Michigan

Posted: Wed Feb 18, 2009 5:58 pm Post subject: Seasonal change reminder

See my answer earlier to Jim Crowder. When I find out their method  

I'll post it, but it seems like if you find the torque going over the  

maximum, you'd have to back it off and start over. But if the torque  

is too high, then wouldn't the wood fibers already have been crushed,  

and wouldn't it be better to leave it at that setting? That  is the  

question that I'll be asking Sensenich.



In fact, there are connecting rod bolts on some engines (can't recall  

which) that are "torqued" by tightening until a micrometer  

measurement taken on the length of the bolt reveals a certain  

stretching has been reached. How'd you like to have to do this on  

every bolt in an engine?



I've seen nuts strip by overtorqueing, and it didn't do the bolt any  

good, but it wasn't necked. I've seen necked bolts too.



Lynn Matteson

Kitfox IV Speedster, taildragger

Jabiru 2200, #2062, 605 hrs

Sensenich 62x46

Electroair direct-fire ignition system

New skis done and flying

do not archive



On Feb 18, 2009, at 8:07 PM, Noel Loveys wrote:



[quote] 



 Next question: How do you check if the torque is too high?  The  

 only way I

 know of is to loosen the bolts and then re-torque them to spec.  If  

 the good

 folks at Sensenich have a method to do this without first loosening  

 please

 let me know.



 If a bolt is too loose then checking the torque is no problem, just  

 torque

 it to spec.  I agree with you humidity certainly can change the  

 pinch on a

 bolt. Therefore the torque the bolt sees.



 One of the things they made us do in our first year of technical  

 school was

 to do stress tests on bolts.  Before pulling apart a bolt will  

 actually

 noticeably stretch...  It's called necking ( just like in the back  

 seat of

 the 68 Mustang ) but the bolt gets noticeably thinner at the point  

 where it

 stretches.  Funny thing is I can't remember seeing a nut giveway.



 Noel



 --

_________________
Lynn
Kitfox IV-Jabiru 2200
N369LM

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Wed Feb 18, 2009 6:44 pm Post subject: Seasonal change reminder

I did it using a known weight hung on the handle at a specific distance ( 5

- 10 in. )  I just nipped the square end into the vice and hung 20 lb on the

horizontal handle at the appropriate distances.  I found my click stop

wrench clicked at 187 in lb when set for 200 lb.  was about 7% too high.  I

have checked the calibration since then every year Usually in the spring but

have found no changes in it.



I have been told that the torque bar type wrenches don't have to be

calibrated as the bars don't tend to weaken.  In fact the calibration

machines they use to calibrate click type wrenches is actually a torque bar

under the panel.  I'd still calibrate it at least once just to make myself

happier.  I've also been told that the new digital wrenches, if anyone can

afford them, are guaranteed to retain their calibration for ten years.  Does

that mean at 10 yr + 1 day it gets replaced?



Noel



--

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

thesupe(at)hotmail.com
Guest

Posted: Wed Feb 18, 2009 7:14 pm Post subject: Seasonal change reminder

Hi Lynn C  can't you calibrate your bending bar torque wrench by putting the socket end in a vice with the wrench horizontal C and then hanging a known weight on the handle 12" out from the center of the socket fitting?  If you hang 10 lbs on C it should read 10 lbs on the pointer if the wrench is accurate C ect C ect.  I know I've done that.  Jim Chuk  Avid MK IV Mn

 

[quote] From: lynnmatt(at)jps.net

 Subject: Re: Re: Seasonal change reminder

 Date: Wed C 18 Feb 2009 20:03:46 -0500

 To: kitfox-list(at)matronics.com

 

 --> Kitfox-List message posted by: Lynn Matteson <lynnmatt(at)jps.net>

 

 If you have a "bending bar" style C it's easy to tell...but I 

 don't...not in the inch-pound size anyway. If you have the "click 

 type" it's only possible to set it at the maximum and if it goes 

 there without clicking over C it's at that maximum or too high. I like 

 to use the inch-pound C as it's newer C but I may start to use the 

 bending bar ft-lb wrench C and check at 10-13 ft-lbs C but that's at 

 the low end of the scale and I can't be sure of its accuracy at that 

 low a setting. I should probably get it calibrated C but how many guys 

 do that?

 

 Lynn Matteson

 Kitfox IV Speedster C taildragger

 Jabiru 2200 C #2062 C 605 hrs

 Sensenich 62x46

 Electroair direct-fire ignition system

 New skis done and flying

 

 

 

 

 On Feb 18 C 2009 C at 6:59 PM C Jim Crowder wrote:

 

 > --> Kitfox-List message posted by: "Jim Crowder" 

 > <jcrowder(at)lpbroadband.net>

 >

 > Lynn C

 > How do you know when it is too high?

 >

 > Jim Crowder

 >

 >> --

jcorner(at)shaw.ca
Guest

Posted: Wed Feb 18, 2009 9:19 pm Post subject: Seasonal change reminder

Noel



Don't like your advice here as it does not  take into consideration  

the weight of

the wrench handle.  This weight could account for your original 7%  

error which

  means you have been applying too much torque on all your fastenings.

You need to mount your wrench in the vice so the square end faces down,

then use a string and pulley arrangement with the known weight to  

calibrate.



Jim





On 18-Feb-09, at 7:43 PM, Noel Loveys wrote:






I did it using a known weight hung on the handle at a specific  

distance ( 5

- 10 in. )  I just nipped the square end into the vice and hung 20 lb  

on the

horizontal handle at the appropriate distances.  I found my click stop

wrench clicked at 187 in lb when set for 200 lb.  was about 7% too  

high.  I

have checked the calibration since then every year Usually in the  

spring but

have found no changes in it.



I have been told that the torque bar type wrenches don't have to be

calibrated as the bars don't tend to weaken.  In fact the calibration

machines they use to calibrate click type wrenches is actually a  

torque bar

under the panel.  I'd still calibrate it at least once just to make  

myself

happier.  I've also been told that the new digital wrenches, if  

anyone can

afford them, are guaranteed to retain their calibration for ten  

years.  Does

that mean at 10 yr + 1 day it gets replaced?



Noel



--

Lynn Matteson

Joined: 10 Jan 2006
Posts: 2778
Location: Grass Lake, Michigan

Posted: Thu Feb 19, 2009 3:21 am Post subject: Seasonal change reminder

Yes, the digital wrench should be considered junk and should be sent  

to me for proper disposal. : )

Lynn Matteson

Kitfox IV Speedster, taildragger

Jabiru 2200, #2062, 605 hrs

Sensenich 62x46

Electroair direct-fire ignition system

New skis done and flying

do not archive



On Feb 18, 2009, at 9:43 PM, Noel Loveys wrote:



 	  Quote: 	
		   



 I did it using a known weight hung on the handle at a specific  

 distance ( 5

 - 10 in. )  I just nipped the square end into the vice and hung 20  

 lb on the

 horizontal handle at the appropriate distances.  I found my click stop

 wrench clicked at 187 in lb when set for 200 lb.  was about 7% too  

 high.  I

 have checked the calibration since then every year Usually in the  

 spring but

 have found no changes in it.



 I have been told that the torque bar type wrenches don't have to be

 calibrated as the bars don't tend to weaken.  In fact the calibration

 machines they use to calibrate click type wrenches is actually a  

 torque bar

 under the panel.  I'd still calibrate it at least once just to make  

 myself

 happier.  I've also been told that the new digital wrenches, if  

 anyone can

 afford them, are guaranteed to retain their calibration for ten  

 years.  Does

 that mean at 10 yr + 1 day it gets replaced?



 Noel

_________________
Lynn
Kitfox IV-Jabiru 2200
N369LM

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Thu Feb 19, 2009 7:09 am Post subject: Seasonal change reminder

Jim:  

Math wasn’t my big subject either.  

10lb. X 12 in. = 120 lb.in.  

I calibrated my wrench by putting 20 lb. (Javex bottle with sand in it) at 5 in  =100 lb. in.  20 lb. X 5 in. = 100 lb.in.  

20 lb (at) 6 in. =  120 lb.in.  

20 lb.(at) 7 in. =  140 lb.in.  

20 lb.(at) 8 in. =  160 lb.in....  

All the way up to   

20 lb.(at) 13 in. = 260 lb.in.  

I think my wrench is only rated up to 300 lb.in. and most of my bolts are spec. to 200 lb.in..Truth is I ran out of handle and was too lazy to add weight.  

The calibration on my wrench requires I set the wrench at 187 lb.in. for 200 lb.in..  I made out a little card similar to the compass card which I keep with my wrench.  

BTW this method while accurate is not a legal method of calibrating a wrench in Canada for use in an AMO ( U.S. FBO)  I expect the same is true South of the 49th.  

Noel  

From: owner-kitfox-list-server(at)matronics.com [mailto:owner-kitfox-list-server(at)matronics.com] On Behalf Of Jim_and_Lucy Chuk

 Sent: Wednesday, February 18, 2009 11:43 PM

 To: kitfox list

 Subject: RE: Re: Seasonal change reminder  

Hi Lynn,  can't you calibrate your bending bar torque wrench by putting the socket end in a vice with the wrench horizontal, and then hanging a known weight on the handle 12" out from the center of the socket fitting?  If you hang 10 lbs on, it should read 10 lbs on the pointer if the wrench is accurate, ect, ect.  I know I've done that.  Jim Chuk  Avid MK IV Mn

 > From: lynnmatt(at)jps.net

 > Subject: Re: Re: Seasonal change reminder

 > Date: Wed, 18 Feb 2009 20:03:46 -0500

 > To: kitfox-list(at)matronics.com

 > 

 > --> Kitfox-List message posted by: Lynn Matteson <lynnmatt(at)jps.net>

 > 

 > If you have a "bending bar" style, it's easy to tell...but I 

 > don't...not in the inch-pound size anyway. If you have the "click 

 > type" it's only possible to set it at the maximum and if it goes 

 > there without clicking over, it's at that maximum or too high. I like 

 > to use the inch-pound, as it's newer, but I may start to use the 

 > bending bar ft-lb wrench, and check at 10-13 ft-lbs, but that's at 

 > the low end of the scale and I can't be sure of its accuracy at that 

 > low a setting. I should probably get it calibrated, but how many guys 

 > do that?

 > 

 > Lynn Matteson

 > Kitfox IV Speedster, taildragger

 > Jabiru 2200, #2062, 605 hrs

 > Sensenich 62x46

 > Electroair direct-fire ignition system

 > New skis done and flying

 > 

 > 

 > 

 > 

 > On Feb 18, 2009, at 6:59 PM, Jim Crowder wrote:

 > 

 > > --> Kitfox-List message posted by: "Jim Crowder" 

 > > <jcrowder(at)lpbroadband.net>

 > >

 > > Lynn,

 > > How do you know when it is too high?

 > >

 > > Jim Crowder

 > >

 > >> --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

thesupe(at)hotmail.com
Guest

Posted: Thu Feb 19, 2009 7:33 am Post subject: Seasonal change reminder

Hi Noel C  I was refering to the last part of Lynn's message where he says he may start using his ft-lb wrench and torque to 10 -13 ft-lb.  I suppose I should have said hand the 10 lbs 1 foot out on the wrench instead of 12" as it may seem like I was referring to an inch-lb wrench when I ment a ft-lb wrench.  Jim Chuk  Avid MK IV  Mn.  

 

  From: noelloveys(at)yahoo.ca

To: kitfox-list(at)matronics.com

Subject: RE: Re: Seasonal change reminder

Date: Thu C 19 Feb 2009 11:38:41 -0330



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Jim: 

  

Math wasn’t my big subject either. 

10lb. X 12 in. = 120 lb.in. 

  

I calibrated my wrench by putting 20 lb. (Javex bottle with sand in it) at 5 in  =100 lb. in.  20 lb. X 5 in. = 100 lb.in. 

20 lb (at) 6 in. =  120 lb.in. 

20 lb.(at) 7 in. =  140 lb.in. 

20 lb.(at) 8 in. =  160 lb.in.... 

All the way up to  

20 lb.(at) 13 in. = 260 lb.in. 

  

I think my wrench is only rated up to 300 lb.in. and most of my bolts are spec. to 200 lb.in..Truth is I ran out of handle and was too lazy to add weight. 

  

The calibration on my wrench requires I set the wrench at 187 lb.in. for 200 lb.in..  I made out a little card similar to the compass card which I keep with my wrench. 

  

BTW this method while accurate is not a legal method of calibrating a wrench in Canada for use in an AMO ( U.S. FBO)  I expect the same is true South of the 49th. 

  

Noel 

    

From: owner-kitfox-list-server(at)matronics.com [mailto:owner-kitfox-list-server(at)matronics.com] On Behalf Of Jim_and_Lucy Chuk

Sent: Wednesday C February 18 C 2009 11:43 PM

To: kitfox list

Subject: RE: Kitfox-List: Re: Seasonal change reminder



 

  

Hi Lynn C  can't you calibrate your bending bar torque wrench by putting the socket end in a vice with the wrench horizontal C and then hanging a known weight on the handle 12" out from the center of the socket fitting?  If you hang 10 lbs on C it should read 10 lbs on the pointer if the wrench is accurate C ect C ect.  I know I've done that.  Jim Chuk  Avid MK IV Mn

 

[quote] From: lynnmatt(at)jps.net

 Subject: Re: Re: Seasonal change reminder

 Date: Wed C 18 Feb 2009 20:03:46 -0500

 To: kitfox-list(at)matronics.com

 

 --> Kitfox-List message posted by: Lynn Matteson <lynnmatt(at)jps.net>

 

 If you have a "bending bar" style C it's easy to tell...but I 

 don't...not in the inch-pound size anyway. If you have the "click 

 type" it's only possible to set it at the maximum and if it goes 

 there without clicking over C it's at that maximum or too high. I like 

 to use the inch-pound C as it's newer C but I may start to use the 

 bending bar ft-lb wrench C and check at 10-13 ft-lbs C but that's at 

 the low end of the scale and I can't be sure of its accuracy at that 

 low a setting. I should probably get it calibrated C but how many guys 

 do that?

 

 Lynn Matteson

 Kitfox IV Speedster C taildragger

 Jabiru 2200 C #2062 C 605 hrs

 Sensenich 62x46

 Electroair direct-fire ignition system

 New skis done and flying

 

 

 

 

 On Feb 18 C 2009 C at 6:59 PM C Jim Crowder wrote:

 

 > --> Kitfox-List message posted by: "Jim Crowder" 

 > <jcrowder(at)lpbroadband.net>

 >

 > Lynn C

 > How do you know when it is too high?

 >

 > Jim Crowder

 >

 >> --

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Thu Feb 19, 2009 8:59 am Post subject: Seasonal change reminder

Just what kind of a honkin' monster wrench do you think I have?  But you are

right!  The application of weight to the handle does not take into account

the weight of the handle itself.  I just crawled out through the snow drift

Ma Nature put in my driveway yesterday and retrieved my wrench which I have

weighed.  The weight on the handle when supported by  stud is 5 oz. Or .3125

lb so at 10 inches that would add 3.125lb. in to my calibration.  So at 187

lb in indicated (200 previously calculated true) I'm actually getting 203

lb. in. torque  this means my wrench is even further out than I thought.

Still within 1.5% accuracy assuming my scales are accurate to that extent.



 I have a friend in Gander who has a calibration machine  I think I'll give

him a visit.



Thanks 



Noel 



--

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

jcorner(at)shaw.ca
Guest

Posted: Thu Feb 19, 2009 9:22 am Post subject: Seasonal change reminder

Noel

You completely missed my point.  You did not take the weight of the wrench into consideration by simply adding weights to the handle.

Suppose the wrench weighs 2 lb. and is 14 in. long.  If you support that wrench at one end you have an effective torque approximately 

equal to 2 lb. acting over 7 inches which is 14 lb. in.  You can see that this is approximately what you call your calibration error.

I suggested that you were over-torquing as I thought you had re-calibrated the wrench instead of using a correction card.

Using that method, you are under torquing rather than over

Jim    



On 19-Feb-09, at 8:08 AM, Noel Loveys wrote:

Jim:

 

Math wasn’t my big subject either.

10lb. X 12 in. = 120 lb.in.

 

I calibrated my wrench by putting 20 lb. (Javex bottle with sand in it) at 5 in  =100 lb. in.  20 lb. X 5 in. = 100 lb.in.

20 lb (at) 6 in. =  120 lb.in.

20 lb.(at) 7 in. =  140 lb.in.

20 lb.(at) 8 in. =  160 lb.in....

All the way up to

20 lb.(at) 13 in. = 260 lb.in.

 

I think my wrench is only rated up to 300 lb.in. and most of my bolts are spec. to 200 lb.in..Truth is I ran out of handle and was too lazy to add weight.

 

The calibration on my wrench requires I set the wrench at 187 lb.in. for 200 lb.in..  I made out a little card similar to the compass card which I keep with my wrench.

 

BTW this method while accurate is not a legal method of calibrating a wrench in Canada for use in an AMO ( U.S. FBO)  I expect the same is true South of the 49th.

 

Noel

 

From: owner-kitfox-list-server(at)matronics.com [mailto:owner-kitfox-list-server(at)matronics.com (owner-kitfox-list-server(at)matronics.com)] On Behalf Of Jim_and_Lucy Chuk

Sent: Wednesday, February 18, 2009 11:43 PM

To: kitfox list

Subject: RE: Re: Seasonal change reminder

 

Hi Lynn,  can't you calibrate your bending bar torque wrench by putting the socket end in a vice with the wrench horizontal, and then hanging a known weight on the handle 12" out from the center of the socket fitting?  If you hang 10 lbs on, it should read 10 lbs on the pointer if the wrench is accurate, ect, ect.  I know I've done that.  Jim Chuk  Avid MK IV Mn

 

[quote] From: lynnmatt(at)jps.net (lynnmatt(at)jps.net)

 Subject: Re: Re: Seasonal change reminder

 Date: Wed, 18 Feb 2009 20:03:46 -0500

 To: kitfox-list(at)matronics.com (kitfox-list(at)matronics.com)

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Thu Feb 19, 2009 12:28 pm Post subject: Seasonal change reminder

Jim:  

Like I said math wasn’t my forte.  Apparently it still isn’t.   I should have noticed that.  I guess the reason I didn’t is generally on small planes the props are usually torque in lb.in..  not lb.ft..  

Noel  

From: owner-kitfox-list-server(at)matronics.com [mailto:owner-kitfox-list-server(at)matronics.com] On Behalf Of Jim_and_Lucy Chuk

 Sent: Thursday, February 19, 2009 11:59 AM

 To: kitfox list

 Subject: RE: Re: Seasonal change reminder  

Hi Noel,  I was refering to the last part of Lynn's message where he says he may start using his ft-lb wrench and torque to 10 -13 ft-lb.  I suppose I should have said hand the 10 lbs 1 foot out on the wrench instead of 12" as it may seem like I was referring to an inch-lb wrench when I ment a ft-lb wrench.  Jim Chuk  Avid MK IV  Mn.  

From: noelloveys(at)yahoo.ca

 To: kitfox-list(at)matronics.com

 Subject: RE: Re: Seasonal change reminder

 Date: Thu, 19 Feb 2009 11:38:41 -0330    

Jim:  

Math wasn’t my big subject either.  

10lb. X 12 in. = 120 lb.in.  

I calibrated my wrench by putting 20 lb. (Javex bottle with sand in it) at 5 in  =100 lb. in.  20 lb. X 5 in. = 100 lb.in.  

20 lb (at) 6 in. =  120 lb.in.  

20 lb.(at) 7 in. =  140 lb.in.  

20 lb.(at) 8 in. =  160 lb.in....  

All the way up to   

20 lb.(at) 13 in. = 260 lb.in.  

I think my wrench is only rated up to 300 lb.in. and most of my bolts are spec. to 200 lb.in..Truth is I ran out of handle and was too lazy to add weight.  

The calibration on my wrench requires I set the wrench at 187 lb.in. for 200 lb.in..  I made out a little card similar to the compass card which I keep with my wrench.  

BTW this method while accurate is not a legal method of calibrating a wrench in Canada for use in an AMO ( U.S. FBO)  I expect the same is true South of the 49th.  

Noel  

From: owner-kitfox-list-server(at)matronics.com [mailto:owner-kitfox-list-server(at)matronics.com] On Behalf Of Jim_and_Lucy Chuk

 Sent: Wednesday, February 18, 2009 11:43 PM

 To: kitfox list

 Subject: RE: Re: Seasonal change reminder  

Hi Lynn,  can't you calibrate your bending bar torque wrench by putting the socket end in a vice with the wrench horizontal, and then hanging a known weight on the handle 12" out from the center of the socket fitting?  If you hang 10 lbs on, it should read 10 lbs on the pointer if the wrench is accurate, ect, ect.  I know I've done that.  Jim Chuk  Avid MK IV Mn

 > From: lynnmatt(at)jps.net

 > Subject: Re: Re: Seasonal change reminder

 > Date: Wed, 18 Feb 2009 20:03:46 -0500

 > To: kitfox-list(at)matronics.com

 > 

 > --> Kitfox-List message posted by: Lynn Matteson <lynnmatt(at)jps.net>

 > 

 > If you have a "bending bar" style, it's easy to tell...but I 

 > don't...not in the inch-pound size anyway. If you have the "click 

 > type" it's only possible to set it at the maximum and if it goes 

 > there without clicking over, it's at that maximum or too high. I like 

 > to use the inch-pound, as it's newer, but I may start to use the 

 > bending bar ft-lb wrench, and check at 10-13 ft-lbs, but that's at 

 > the low end of the scale and I can't be sure of its accuracy at that 

 > low a setting. I should probably get it calibrated, but how many guys 

 > do that?

 > 

 > Lynn Matteson

 > Kitfox IV Speedster, taildragger

 > Jabiru 2200, #2062, 605 hrs

 > Sensenich 62x46

 > Electroair direct-fire ignition system

 > New skis done and flying

 > 

 > 

 > 

 > 

 > On Feb 18, 2009, at 6:59 PM, Jim Crowder wrote:

 > 

 > > --> Kitfox-List message posted by: "Jim Crowder" 

 > > <jcrowder(at)lpbroadband.net>

 > >

 > > Lynn,

 > > How do you know when it is too high?

 > >

 > > Jim Crowder

 > >

 > >> --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

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