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-   -   NEW! Ultimate C/S Prop Wrench Anti Splat Aero (https://vansairforce.net/community/showthread.php?t=82592)

gasman 02-20-2012 08:32 PM

Quote:

Originally Posted by Rv8ter (Post 631224)
all this discussion has the basic principle of torque changed?

In most wrench applications the force relationship may be expressed by the following formula:

F x D = T
FORCE x DISTANCE = TORQUE

Where:

F equals turning force in pounds applied by the Operator.

D equals lever arm or wrench handle in inches or feet.(Whatever the distance)

T equals total force applied to wrench head in pound-feet, kilopoint-meters or Newton-meters

I'll just continue to keep it simple!
My money is with Allan on this one! ;)

The argument is not over the basic principle of torque.............

The argument is over "How A Torque Wrench Functions."

PerfTech 02-20-2012 08:54 PM

Quote:

Originally Posted by gasman (Post 631387)
The argument is not over the basic principle of torque.............

The argument is over "How A Torque Wrench Functions."

I am not making any statements as to how anyone's torque wrench functions, where they should grip it or advocating the use of a piece of pipe on the end of it. I am saying how to properly use our tool or any torque adapter and will try to shoot a video tomorrow night. In this case "IT aint over till the fat guy makes video":D

380mxc 02-20-2012 09:17 PM

The disscusion
 
Quote:

Originally Posted by PerfTech (Post 628818)
All foot lb. torque wrenches are the same regardless of handle overall length. The overall length only effects how hard you need to pull on it. on a foot lb. torque wrench the .8 multiplier is exactly and always the number. It is not rounded off and it never changes as long as the crows foot or our tool is 3" and in installed straight.

This statment is the one in question. And the safe use of torque wrenches longer than 12"

Safety first.

PerfTech 02-20-2012 10:11 PM

Quote:

Originally Posted by 380mxc (Post 631410)
This statment is the one in question. And the safe use of torque wrenches longer than 12"

Safety first.

You don't need to talk safety to me. If you have been to our web site you would be aware that all of our offerings are pointed to improve safety. We have invested many thousands in developing and importing products for the RV community. I intend to address this safety issue is my video that will be up in a few days. After posting the video, I will put the prop wrenches up again in the classifieds, for now I won't sell any more until this is put to bed. Allan

WAM120RV 02-21-2012 05:25 AM

Good Guys
 
Hey Allan you will always be one of the Good Guys in my book!

Keep developing items like this, dont let this little side show stop you coming up with good engineering solutions.

I think your nose job is great and I might be in a position to order one next month, hopefully Peter will have got his through the UK system by then.

444TX 02-21-2012 03:06 PM

x .8 ?? debate
 
The debate here is the accuracy of using the x .80 conversion for getting the desired fastener torque when using a 3 inch torque extension regardless of the torque wrench effective handle length.

Any debate on where to grip the torque wrench or adding extensions to the handle has little merit. The wrenches are calibrated with the handle pulled at a particular spot and videos show that final torque can be effected by hand position. Using a different technique would require verification to show accuracy. Just because it clicks or indicates a value does not mean that the indicated value is the same as the fastener actual torque value without verification.

The industry standard is to use the formula in FAA AC 43.13-1B (chapter 7), instructions that come with the torque wrench or the formula posted in this thread. They are all the same. The result of the formula is different for different torque wrench effective handle lengths. When using a 3 inch extension the .8 formula only works with a 12 inch effective handle length.

I have a digital Snap-On 1/2 drive torque wrench with an effective handle length of 22.18 inches (total handle length, center of square to handle end, is 25.375 inches). Using the 43.13 formula when torquing a Harzell prop to 65ft/lb the S-O wrench would require a 57.25 ft/lb indicated setting/reading when using a 3 inch torque extension. If the .8 formula was used with the S-O wrench, the indicated wrench setting/reading would be 52 ft/lb (65 x .8). When taking the 43.13 formula and converting the indicated 52 ft/lb (from the .8 formula) back to the actual torque at the fastener the result is 59.03 ft/lbs. If the widely accepted formula is correct, the fastener would be under torqued by almost 10%.

Using a 60 ft/lb desired torque (the minimum Hartzell torque value) one would only get a fastener torque of 54.49 ft/lb using the S-O wrench, 3 inch extension, .8 multiple for the desired torque and running the numbers backwards with the industry used formula. 5.51 ft/lb below the recommended minimum torque.

There is actually more going on here than simply adding a longer arm to get leverage. The torque wrench is only measuring the twisting force centered on the drive hole in the torque extention. The second force is the pressure neccessary to move the torque extension in an arc centered on the torque extension pivot point. (post #296) The 43.13 formula takes this all in to consideration.

I like Allan's tool and may purchase one. I am still waiting for his video and would hope there are torque wrenches much longer than 12 inches used in the comparison.

George
RV8

PerfTech 02-21-2012 10:58 PM

Coming video!!!!!!!
 
I set up and shot some video tonight and need to do a little editing (to long). Should post in a day or so. Regards all, Allan:rolleyes:

erich weaver 02-21-2012 11:20 PM

Those exclamation marks from Allan look awfully enthusiastic...

Erich

LAMPSguy 02-22-2012 06:32 AM

Gifts!
 
Quote:

Originally Posted by Mel (Post 631294)
Because.....IT'S A TOOL!!!!!!!!!

You don't need an excuse to buy a tool!

I once explained this to my wife, told her if she needed a gift idea, find a tool I don't have, made in USA, and buy it!

swordtail 02-22-2012 10:13 AM

if you can find it, snap-on form SS428A-3A called "Bolts, Tension and Torque"
16 pages of answers. or form SB565A titled "Torque Problems" or SS1276 called "threaded fasteners & torque" if you can get them. The formula that we used for extensions and adaptors. Lever length of the wrench is extended
reading correction required! Calculation is requiredto find new reading (NR)

NR = L X T / L + E where T is torque value required
L = length of torque wr from
hand position to center of sq drive
E= extension length from center of sq
to center of hex.
NR= dial numeral representing torque value required
formula are tough in a post but I hope you get the idea.

Bob Kuykendall 02-24-2012 09:53 AM

Quote:

Originally Posted by PerfTech (Post 630093)
...I graduated top of my class at MIT with three degrees in mechanical engineering...

Not that I put much emphasis on credentials, but just to clarify this point: When you say MIT, do you mean Massachusetts Institute of Technology?

Thanks, Bob K.

fatherson 02-24-2012 05:01 PM

I answered this question from Mike Starkey in another thread on this debate:
Quote:

Originally Posted by Mike S (Post 630311)
If I use an electric motor, with an adjustable clutch set to slip at 100 lb/ft of torque on the output shaft, and then attach the 3" tool at the end of that shaft, how much torque will the end of the tool see????

I can't see anywhere Mike's question was addressed, so let me repeat my answer here:
The nut will see absolutely no torque at all.
Think about it or try it out to prove to yourself that it's true. I think this proves the correction multipler cannot be a constant.

Hope that helps.

--
Stephen

speyers 02-24-2012 07:10 PM

90 degrees
 
For the love of mary, put the thing on 90 degrees and be done with it! Or calibrate your elbow... seriously. Does anybody really torque spark plugs, an 3 bolts, brake backing plates or mag attach nuts?

PCHunt 02-24-2012 09:09 PM

I torque spark plugs every time. One stripped thread in the cylinder isn't worth it to me. Without a torque wrench, I tend to over-torque stuff, especially AN-3 stuff.

I really have to watch it!........ :o

BillL 02-24-2012 09:12 PM

Sorry to do this, but . . .
 
Quote:

Originally Posted by fatherson (Post 632812)
I answered this question from Mike Starkey in another thread on this debate:


I can't see anywhere Mike's question was addressed, so let me repeat my answer here:
The nut will see absolutely no torque at all.
Think about it or try it out to prove to yourself that it's true. I think this proves the correction multipler cannot be a constant.

Hope that helps.

--
Stephen

Actually I was wondering when this could come up. There are two rules of statics, 1. summing forces about a point = zero 2. a pure moment can be located anywhere on the plane.

So . . . Mike's pure torque of 100 will result be resisted by an equal torque at the nut. There are no force couples involved. the distance is not relevant since there is no force couple involved.

OK, all ready to pull your hair out now?

Think about it . . . if you applied a pure torque to that wrench and it was not attached, what would happen - it would spin, right? So the reaction at the nut can NOT be zero and the real answer is it is equal to that applied.

For the extension - use the FAA and torque wrench book formula.

Why? Lets say the FAA is correct - the factor is not fixed at 0.8 . But I use the 0.8 anyway. The prop torque needs 60-70 ft-lb of torque. I usually use the middle number since i don't know which way my tool may be inaccurate. So let's use 65 ft-lb. If I use a 16.5 inch wrench ( my real number) and using the .8 factor, I will be actually 6.7% low, according to the FAA formula. What if my click wrench is 4% low? Then I am 10.7% low now, or only 58 ft-lb of real torque on the nut. That is 2 ft-lb below the low end of the range. Is that enough to worry? I don't know, so I will be using what my engineering training, experience, and the FAA formula tells me.

Wayne Gillispie 02-24-2012 10:47 PM

It is after midnight...
 
I just had to see what all the huboob was about and clicked on this thread. I read every post to page 11. I said to my aching brain...let's skip to the last page and there I will find out if the length really does matter. Okay, I can sleep tonight since I have been flying behind my prop that was torqued with a 90 deg adapter. We used the same formula that is in AC43.13 in the military. I would hate to have to go back and recheck torques from 23 years ago. I am going to bed, my calibrated elbow is hurting too.

Now I figured out why Mike Starkey was recommending to a new builder "torque wrench how-to lessons" before starting his -10 emp. I was wondering what kind of crazy recommendation was that.:D

Mike S 02-24-2012 11:56 PM

Quote:

Originally Posted by Wayne Gillispie (Post 632894)
Now I figured out why Mike Starkey was recommending to a new builder "torque wrench how-to lessons" before starting his -10 emp. I was wondering what kind of crazy recommendation was that.:D

That recommendation was to help him sleep.

PCHunt 02-25-2012 12:56 AM

Found a nice online calculator
 
It even (correctly) takes into account the angle-off of the adapter.

http://www.cncexpo.com/TorqueAdapter.aspx

Try putting an angle of 180 degrees in, see what happens. You can change the length to see the results as well.

fatherson 02-25-2012 01:00 AM

Quote:

Originally Posted by BillL (Post 632870)
Think about it . . . if you applied a pure torque to that wrench and it was not attached, what would happen - it would spin, right? So the reaction at the nut can NOT be zero and the real answer is it is equal to that applied.

You know, even as dusty as my statics and four years of physics are, Bill's counterpoint to my claim above sounds right. I'm tired and just checked into VAF for a few seconds on my way to bed, but I couldn't let my probable error stand overnight unchecked. I'll revisit this again once I have time to sketch a proper force diagram to figure out where my intuition went wrong. At least Bill and I agree that trusting the science is the right approach.

--
Stephen

scsmith 02-25-2012 01:31 AM

Both could be right! Advanced Statics....
 
Quote:

Originally Posted by fatherson (Post 632910)
You know, even as dusty as my statics and four years of physics are, Bill's counterpoint to my claim above sounds right. I'm tired and just checked into VAF for a few seconds on my way to bed, but I couldn't let my probable error stand overnight unchecked. I'll revisit this again once I have time to sketch a proper force diagram to figure out where my intuition went wrong. At least Bill and I agree that trusting the science is the right approach.

--
Stephen

Actually, depending on how you hold the impact wrench, either solution is possible.

In case 1, you do your best to hold the impact driver still. In doing so, you provide a reaction force that counters the wrench interaction on the nut. You get a force couple that cancels the moment, with no torque on the nut.

In case 2, you do not resist the motion of the impact wrench, only its rotation. The wrench will try to orbit the nut, and in doing so, transmit the pure torque to it with no force couple. This assumes it does not orbit so fast that centrifugal force throws it off the nut though! :rolleyes:

PCHunt 02-25-2012 01:46 AM

Quote:

Originally Posted by BillL (Post 632870)
............Think about it . . . if you applied a pure torque to that wrench and it was not attached, what would happen - it would spin, right? So the reaction at the nut can NOT be zero and the real answer is it is equal to that applied.

Yes, the adapter would spin if it was not attached to anything. Watch out, don't let your fingers get in the way!!

But when attached to the nut, it would apply ONLY a 90-degree side-load on the nut, and ZERO turning force. No torque would be applied to the nut.

In order to twist the nut with torque, the square-drive end of the adapter has to move sideways through an arc, which the electric motor with a slip-clutch can not provide.

EDIT: This was posted before I saw Steve Smith's post. I am NOT an aero engineer!!! YMMV. Do your own testing. My .02, etc. :rolleyes:

380mxc 02-25-2012 08:04 AM

Large order
 
Wrench Order

--------------------------------------------------------------------------------
...When I came in today I received a purchase order from one of the largest propeller manufacturers in the world for 250 of our tools. They requested that we stamp into the tool the multiplier < TRQ X .8 > So their customers will use it correctly and avoid any confusion.
...The purchasing agent that I spoke to said they are having quite the laughing session throughout their facility over this. He informed me that they actually have one of the on line calculators posted for people to use. He said in their instructions is that popular diagram that keeps popping up, they never dreamed anyone would be so misinformed as to not understand that the L dimension is always 12" with all ft lb tools. I'm Happy Today! Allan
__________________
Allan Nimmo
AntiSplatAero.com
Innovative Aircraft Products
Info@AntiSplatAero.com
Southern California (KREI)
RV-9A / Extra-300

Great! Which Prop manufacturer?

erich weaver 02-25-2012 08:59 AM

Allan said:"The purchasing agent that I spoke to said they are having quite the laughing session throughout their facility over this. He informed me that they actually have one of the on line calculators posted for people to use. He said in their instructions is that popular diagram that keeps popping up, they never dreamed anyone would be so misinformed as to not understand that the L dimension is always 12" with all ft lb tools."


I have quite the opposite impression when I look at all the manuals, the AC and online calculators. Laugh all you want, but I don't know how anyone could possibly think anything other than to use the actual length of their particular torque wench. The meaning of L is explicitly shown in the diagrams. I haven't seen ANY documentation for the use of torque wrenches that says that L is always 12 with ft lb torque wrenches. Either Allan and his friendly purchasing agent are very wrong, or all the existing documentation is badly misleading. I await efforts by others to present video demonstrations.

Erich

mcencula 02-25-2012 06:47 PM

Handle length does matter
 
Allan,

While I have great appreciation for the products you are bringing to the RV community and have already purchased the Nose Job and have your prop wrench on order, I humbly submit that I believe you are incorrect in your statement that a .8 multiplier can be applied regardless of the handle length of the torque wrench.

I have taken some time to demonstrate the mathematics in this analysis of the forces and moments involved. I welcome critical review of this analysis and hope it results in improved safety for all...a sentiment you expressed concern for towards the end of your video.

As an aside, I recently viewed your video and while I would agree that this is a first-year engineering student math, it's not 5th grade math. ;)

All the best,

L.Adamson 02-25-2012 07:50 PM

Quote:

Originally Posted by mcencula (Post 633142)
Allan,

While I have great appreciation for the products you are bringing to the RV community and have already purchased the Nose Job and have your prop wrench on order, I humbly submit that I believe you are incorrect in your statement that a .8 multiplier can be applied regardless of the handle length of the torque wrench.

I have taken some time to demonstrate the mathematics in this analysis of the forces and moments involved. I welcome critical review of this analysis and hope it results in improved safety for all...a sentiment you expressed concern for towards the end of your video.

As an aside, I recently viewed your video and while I would agree that this is a first-year engineering student math, it's not 5th grade math. ;)

All the best,

Your analysis shows 60 in-lbs at the bolt head, with a 56 in-lb setting on the 48" wrench. I've been enlarging the video to 800% on my 27" monitor. There is glare on the Snap-On torque gauge, and the numbers become blurry. Therefor, I put some paper against the monitor, and traced the angles of the needle from the straight on shots. It's hard to tell exactly from freezing the frame, but the needle is at least hitting 68+ on the scale. It's definitely much more than 60.

So...............is the SnapOn gauge incorrect? Are the torque wrenches incorrect? Is your mathematics incorrect? Is the time honored mathematics incorrect...

mcencula 02-25-2012 08:15 PM

Quote:

Originally Posted by L.Adamson (Post 633152)
Your analysis shows 60 in-lbs at the bolt head, with a 56 in-lb setting on the 48" wrench. I've been enlarging the video to 800% on my 27" monitor. There is glare on the Snap-On torque gauge, and the numbers become blurry. Therefor, I put some paper against the monitor, and traced the angles of the needle from the straight on shots. It's hard to tell exactly from freezing the frame, but the needle is at least hitting 68+ on the scale. It's definitely much more than 60.

So...............is the SnapOn gauge incorrect? Are the torque wrenches incorrect? Is your mathematics incorrect? Is the time honored mathematics incorrect...

I watched the video a number of times and it looks to me like the needle hits about 64, but all of the tests done in the video are done by hand, so it's hard to say how much if any of that is overshoot after the torque wrench clicks.

After reading your question about which math is right, I looked up what AC43.13-1B has to say about this. I had intentionally not looked it up until after doing the math myself from scratch. Turns out they have the exact same formula (using different variable names) as I do.

Their formula:
T*L/(L+E)=Y

Where:
T is actual torque on the bolt
Y is apparent (indicated) torque (i.e. what you set the torque wrench to)
L is effective length lever
E is effective length extension

Rearranging their formula to show the same ratio as my analysis gives:
T/Y = (L+E)/L ==> T/Y = 1+E/L

Which is identical to what I came up with. Hrm...maybe all those of years of schoolin' paid off after all? ;)

PerfTech 02-25-2012 10:59 PM

PLEASE LOOK AT THIS POST!!!!!!!!
 
Very Important!:o

http://www.vansairforce.com/communit...209#post633209

fehdxl 02-25-2012 11:19 PM

Quote:

Originally Posted by JakeLewis22 (Post 633218)
Does anyone second my request below?

Seconded.

-Jim

JakeLewis22 02-25-2012 11:29 PM

Quote:

Originally Posted by fehdxl (Post 633221)
Seconded.

-Jim

Thanks Jim but right after I posted my request on this string (a copy of post #78 on the FS: ASA Ultimate Prop Wrenches 3/4" & 5/8" forum string) I read Allan's post above and deleted it. It's no longer necessary.

Allan, your credibility just went up 10 fold. It sucks when you're wrong but it takes a big man to admit it.

vlittle 02-25-2012 11:49 PM

Allan must be crazy... like a fox!

The objective of guerilla marketing is to get noticed so you can sell more product. I can unequivocally state that Allan is the biggest guerilla on VAF!

Well done!

mcencula 02-25-2012 11:55 PM

Thanks for the cross reference
 
Quote:

Originally Posted by PerfTech (Post 633210)

Whups...I didn't see your retraction in the other thread, Allan, or I wouldn't have bothered posting. Thanks for clearing things up and bringing some great products to market.

P.S. It might be a good idea to remove those two videos from your website. :)

Bob Kuykendall 02-26-2012 09:48 AM

Quote:

Originally Posted by PerfTech (Post 633210)

There are still two minor points I'd like to see addressed:

1. The retraction linked above is a post to a thread in Classified; so the whole thread is scheduled to disappear in 30 days. That being the case, we have here a situation like many on the Internet where dangerous misinformation outlasts its debunking.

Hello.

I have been asked by the owner of the VAF site (Doug Reeves) to help enforce the forum posting rules. I deleted your recent VAF post about _____Questioning Member's Credentials_____ for the following reason(s):

_X_ Civility / Tone
__ Not RV-related
__ Commercial promotion by non-advertiser
__ Mod/Policy bashing
__ Politics / Government
__ Illegal video clip
__ eBay / Barnstormers / etc.

The posting rules are explained in greater detail at: www.vansairforce.net/rules.htm

If you feel the need, please direct comments regarding this to the owner of the site (Doug Reeves). His contact info can be found at: www.DeltaRomeo.com

Thank you.




Thanks, Bob K.

fehdxl 02-26-2012 11:56 AM

Quote:

Originally Posted by Bob Kuykendall (Post 633323)
1. The retraction linked above is a post to a thread in Classified; so the whole thread is scheduled to disappear in 30 days. That being the case, we have here a situation like many on the Internet where dangerous misinformation outlasts its debunking.

I believe if it's posted like this, it will at least remain quoted even though one can't go back to the original post after 30 days.

Quote:

Originally Posted by PerfTech (Post 633209)
Wow! This is really difficult!:o
-----After seeing this post and its very close parallel to many others I decided to do a little more testing and set up our electronic load cell set ups we use to calibrate our dynamometers information gathering systems.
I didn't use it in the video as I thought it would be to difficult to see on camera and more complicated for most to understand. I immediately began to see errors consistent with some of the posts here. So! to make a long story short I decided to give up on the 5th grade math and and go to some true first year engineering school math. I truly wish I had listened to some of you in the very beginning as I could have saved myself considerable embarrassment here. The math I applied from scratch matched the little online calculators perfectly, thus proving I was wrong in my .8 with any wrench length statement. As most of you have seen the demonstration video I made at considerable expense. I sincerely hope you guys don't think I was trying to mislead or deceive you. I really was trying to do a service, not win the debate. The small errors I picked up on, I attributed to errors of mechanism or wrench design anomalies. At any rate an apology is in order to everyone on both sides of the fence. I feel pretty stupid over this one and learned a valuable lesson. I hope I didn't cause you guys too much stress. The good side of this debate is we sure are selling a lot of products, but I assure you guys, it wasn't planned like that. I hope I haven't alienated too many of you with my hard headed attitude. I Really love this forum and and all who contribute here. Best Regards, Allan:o [ed: bold emphasis added by me]

-Jim

Captain Avgas 02-26-2012 04:51 PM

Quote:

Originally Posted by vlittle (Post 633227)
Allan must be crazy... like a fox!

The objective of guerilla marketing is to get noticed so you can sell more product. I can unequivocally state that Allan is the biggest guerilla on VAF!

Well done!

Well done ?????? :rolleyes:

You seem to be suggesting that Allan Nimmo deliberately provided misleading and unsafe information about his product, knowingly tarnished his credentials, produced a deliberately falsified video of his product being tested, and willingly subjugated himself to a very public humiliation.....all to gain some exposure in order to sell a few low cost prop spanners. :confused:

As far as conspiracy theories goes this is right up there with the Apollo moon landings being faked in a studio on earth. :cool:

No doubt the truth of the matter is far, far simpler.

scsmith 02-26-2012 11:47 PM

The original video is still up
 
The original video that introduced the wrench and made the original statement about the 80% that started the whole discussion is still up on the antisplataero web site.

Allan, wondering if you might edit that?

PerfTech 02-27-2012 01:48 PM

Done!
 
Quote:

Originally Posted by scsmith (Post 633569)
The original video that introduced the wrench and made the original statement about the 80% that started the whole discussion is still up on the antisplataero web site.

Allan, wondering if you might edit that?

Thanks for reminding me of that, I have edited the video to exclude that statement. Allan:)

Mike S 03-19-2012 02:56 PM


9GT 03-19-2012 03:12 PM

PIREP
 
I got to use one of Allan's prop wrench's yesterday to take the Hartzell off my engine and I give it a big thumb's up. It cut the time to remove the prop at least in half and I am now looking forward to using it to re-install the prop in a couple weeks. Thanks for the great products you have developed and made available to us at such a reasonable cost Allan!

PerfTech 04-21-2012 09:49 AM

Quote:

Originally Posted by 9GT (Post 641289)
I got to use one of Allan's prop wrench's yesterday to take the Hartzell off my engine and I give it a big thumb's up. It cut the time to remove the prop at least in half and I am now looking forward to using it to re-install the prop in a couple weeks. Thanks for the great products you have developed and made available to us at such a reasonable cost Allan!

....Thank you so much for the kind words in regards to our tool. We are pleased that it is so well receiver and liked by everyone. Thanks again for your business. Allan....:D


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