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dsavarese0812(at)bellsout
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 Posted: Tue Jun 18, 2019 2:52 am Post subject: What is the cylinder torque value for the nuts at the base. |
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Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
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Cliff.Coy
Joined: 03 Mar 2007
Posts: 46
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| Posted: Tue Jun 18, 2019 5:57 am Post subject: What is the cylinder torque value for the nuts at the base. |
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Common torques are attached.
[img]https://drive-thirdparty.googleusercontent.com/16/type/application/pdf[/img] COMMON TORQUES.pdf
On Tue, Jun 18, 2019 at 6:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
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--
Clifford Coy
Border Air Ltd.
C-Parts Inc.
629 Airport Rd.
Swanton, VT 05488
802-868-2822 TEL
802-868-0035 FAX (MANUAL RECEIVE)
Skype: Cliff.Coy
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JB Soar
Joined: 19 Apr 2019
Posts: 22
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| Posted: Tue Jun 18, 2019 6:05 am Post subject: What is the cylinder torque value for the nuts at the base. |
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Can someone provide a picture of the cylinder base nut wrench? Thank you!
On Tue, Jun 18, 2019 at 9:03 AM Cliff Coy <cliff.coy(at)gmail.com (cliff.coy(at)gmail.com)> wrote:
| Quote: | Common torques are attached.
[img]https://drive-thirdparty.googleusercontent.com/16/type/application/pdf[/img] COMMON TORQUES.pdf
On Tue, Jun 18, 2019 at 6:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
Archive Search & Download, 7-Day Browse, Chat, FAQ,
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--
Clifford Coy
Border Air Ltd.
C-Parts Inc.
629 Airport Rd.
Swanton, VT 05488
802-868-2822 TEL
802-868-0035 FAX (MANUAL RECEIVE)
Skype: Cliff.Coy
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dougsappllc(at)gmail.com
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| Posted: Tue Jun 18, 2019 9:53 am Post subject: What is the cylinder torque value for the nuts at the base. |
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I do believe the question was asked but maybe missed by some of us.What is "wet" torque? What exactly does this mean? If I interpret the cut n past from the net correctly then torquing the cly base studs to 304 to 330 inch pounds WET is way excessive.
From :https://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html
When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below.LubricantTorque Reduction
(%)No lube0Graphite50 - 55White Grease35 - 45SAE 30 oil35 - 45SAE 40 oil30 - 40
On Tue, Jun 18, 2019 at 3:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
Archive Search & Download, 7-Day Browse, Chat, FAQ,
http://ww==================
http://forums.matronics.com
http://www.matronics.com/contr========================
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dougsappllc(at)gmail.com
Guest
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| Posted: Tue Jun 18, 2019 10:29 am Post subject: What is the cylinder torque value for the nuts at the base. |
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Also, from Mark Pennington, this is interesting:https://mail.google.com/mail/u/0/?tab=rm&zx=vl5ywvgzpugl#inbox/FMfcgxwChJkxdFPJVWFSFZcLkGTCcGrW?compose=DmwnWrRnXVSjzwCjrftdqMTFtpZNSfCdPxQgNrBwDsFKJDZfWGgpgdvcrDhTRrHnqLgLwBlQDDDL&projector=1
On Tue, Jun 18, 2019 at 10:52 AM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: | I do believe the question was asked but maybe missed by some of us.What is "wet" torque? What exactly does this mean? If I interpret the cut n past from the net correctly then torquing the cly base studs to 304 to 330 inch pounds WET is way excessive.
From :https://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html
When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below.LubricantTorque Reduction
(%)No lube0Graphite50 - 55White Grease35 - 45SAE 30 oil35 - 45SAE 40 oil30 - 40
On Tue, Jun 18, 2019 at 3:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
Archive Search & Download, 7-Day Browse, Chat, FAQ,
http://ww==================
http://forums.matronics.com
http://www.matronics.com/contr========================
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pennington.construction.i
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| Posted: Tue Jun 18, 2019 11:16 am Post subject: What is the cylinder torque value for the nuts at the base. |
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The video I sent to Doug didn't work on the email. I have attached the link here.
Basically the video illustrates that torque is directly related to clamping force. Most torque specs that I have seen are related to a lubricated bolt or fastener. You will see that achieving a torque value does not guarantee clamping force. Clamping force is the value for a bolt or fastness in an assembly or attached part. Torque can be seen as the resistance to a nut rotational force, not tightness.
Good illustration. You can apply this information to your own work on your plane as needed.
https://www.youtube.com/watch?v=O96AUlIBkU8
Mark Pennington
N621CJ
On Tue, Jun 18, 2019 at 2:33 PM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: | Also, from Mark Pennington, this is interesting:https://mail.google.com/mail/u/0/?tab=rm&zx=vl5ywvgzpugl#inbox/FMfcgxwChJkxdFPJVWFSFZcLkGTCcGrW?compose=DmwnWrRnXVSjzwCjrftdqMTFtpZNSfCdPxQgNrBwDsFKJDZfWGgpgdvcrDhTRrHnqLgLwBlQDDDL&projector=1
On Tue, Jun 18, 2019 at 10:52 AM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: | I do believe the question was asked but maybe missed by some of us.What is "wet" torque? What exactly does this mean? If I interpret the cut n past from the net correctly then torquing the cly base studs to 304 to 330 inch pounds WET is way excessive.
From :https://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html
When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below.LubricantTorque Reduction
(%)No lube0Graphite50 - 55White Grease35 - 45SAE 30 oil35 - 45SAE 40 oil30 - 40
On Tue, Jun 18, 2019 at 3:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
Archive Search & Download, 7-Day Browse, Chat, FAQ,
http://ww==================
http://forums.matronics.com
http://www.matronics.com/contr========================
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wlannon(at)shaw.ca
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| Posted: Tue Jun 18, 2019 1:29 pm Post subject: What is the cylinder torque value for the nuts at the base. |
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Very true Mark;
And why I included the note that torque is a quick and dirty method. Really critical fasteners eg: the pinch bolt holding our engine crank throws in alignment, the connecting rod bolts in aircraft engines like the Merlin, hub assy. bolts in large engine propellors, etc. do not use a torque value at all.
In these and other cases the amount of bolt stretch is directly measured to a specified dimension.
However, the torque method is the basic standard and I will quote from the P & W 985/1340 Overhaul Manual “ Unless otherwise specified in this Manual all nut, bolt and screw torques should be obtained with thread lubricants”
Specifically for the cylinder flange nuts “300 lb/in with lubricant.” They do not specify a lubricant but I can assure you after 60 + years in the business it is aircraft engine oil.
300 lb./in. is the specific value. There is no need for any tolerance and none is given, The nut is locked to the stud by a simple sheet metal nut designed for this purpose called a “palnut”. No f$*(# ing around with tab washers.
The only info I have seen re: our engines is a torque table from M14P. com showing a specific 304 lb/in which I now see has been modified with a max. of 330 lb/in added. No doubt to accommodate the %&#hole tab washers.
The similarity in torque values for quite different engines is interesting but not particularly surprising. The stud size is 0.018” inches larger on our engines with a slightly coarser thread which translates to very similar thread root dia. Stud strength is likely to the same aviation standard. The major difference is simply the number of studs.
Walt
From: Mark Pennington (pennington.construction.inc.1(at)gmail.com)
Sent: Tuesday, June 18, 2019 12:15 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: Re: Re: What is the cylinder torque value for the nuts at the base.
The video I sent to Doug didn't work on the email. I have attached the link here.
Basically the video illustrates that torque is directly related to clamping force. Most torque specs that I have seen are related to a lubricated bolt or fastener. You will see that achieving a torque value does not guarantee clamping force. Clamping force is the value for a bolt or fastness in an assembly or attached part. Torque can be seen as the resistance to a nut rotational force, not tightness.
Good illustration. You can apply this information to your own work on your plane as needed.
https://www.youtube.com/watch?v=O96AUlIBkU8
Mark Pennington
N621CJ
On Tue, Jun 18, 2019 at 2:33 PM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: | Also, from Mark Pennington, this is interesting: https://mail.google.com/mail/u/0/?tab=rm&zx=vl5ywvgzpugl#inbox/FMfcgxwChJkxdFPJVWFSFZcLkGTCcGrW?compose=DmwnWrRnXVSjzwCjrftdqMTFtpZNSfCdPxQgNrBwDsFKJDZfWGgpgdvcrDhTRrHnqLgLwBlQDDDL&projector=1
On Tue, Jun 18, 2019 at 10:52 AM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: | I do believe the question was asked but maybe missed by some of us. What is "wet" torque? What exactly does this mean? If I interpret the cut n past from the net correctly then torquing the cly base studs to 304 to 330 inch pounds WET is way excessive.
From :https://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html
When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below. Lubricant Torque Reduction
(%) No lube 0 Graphite 50 - 55 White Grease 35 - 45 SAE 30 oil 35 - 45 SAE 40 oil 30 - 40
On Tue, Jun 18, 2019 at 3:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
Archive Search & Download, 7-Day Browse, Chat, FAQ,
http://ww==================
http://forums.matronics.com
http://www.matronics.com/contr========================
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pennington.construction.i
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| Posted: Tue Jun 18, 2019 1:58 pm Post subject: What is the cylinder torque value for the nuts at the base. |
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Walt
I agree torque is the normal standard and every race engine that I
assembled along the way used a little product called "Assembly Lube"
apply the lube before the tightening phase of assembly. I am sure motor
oil on our engines is the standard as you suggest. I don't have the
experience you have by far. I have used the same oil I put in the crank
case of the M14 when I assemble things.
Question: I understand the nut welded to the special tool for the cylinder
head nuts. Does that provide an accurate torque value being offset like
it is. ? Or in your experience is the difference negligible? I can see
it would give you consistency for sure.
And yes, I will be checking my cylinder head nuts the next time both cowls
are off. I had contacted Dennis and he said the same thing, weld a nut to
your tool......... Thanks for all of the good info..
Learn something new everyday.
Mark
On Tue, Jun 18, 2019 at 5:34 PM Walter Lannon <wlannon(at)shaw.ca> wrote:
[quote] Very true Mark;
And why I included the note that torque is a quick and dirty method.
Really critical fasteners eg: the pinch bolt holding our engine crank
throws in alignment, the connecting rod bolts in aircraft engines like the
Merlin, hub assy. bolts in large engine propellors, etc. do not use a
torque value at all.
In these and other cases the amount of bolt stretch is directly measured
to a specified dimension.
However, the torque method is the basic standard and I will quote from the
P & W 985/1340 Overhaul Manual “ Unless otherwise specified in this Manual
all nut, bolt and screw torques should be obtained with thread lubricants”
Specifically for the cylinder flange nuts “300 lb/in with lubricant.”
They do not specify a lubricant but I can assure you after 60 + years in
the business it is aircraft engine oil.
300 lb./in. is the specific value. There is no need for any tolerance and
none is given, The nut is locked to the stud by a simple sheet metal nut
designed for this purpose called a “palnut”. No f$*(# ing around with tab
washers.
The only info I have seen re: our engines is a torque table from M14P. com
showing a specific 304 lb/in which I now see has been modified with a max
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n13472(at)aol.com
Guest
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| Posted: Tue Jun 18, 2019 2:27 pm Post subject: What is the cylinder torque value for the nuts at the base. |
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In reply to the earlier thread on the cylinder nuts and gaskets. The two stock Housai engines
I have both had aluminum gaskets under the cylinder’s. During an exhaust valve regrind
the re attachment kits I got had paper gaskets. After approximately ? four years / 200 hours
the first one to fail #9 . I caught it early because of a cyl base oil leak the gasket had failed and
the nuts were loose. I pulled it cyl and replaced the gasket with an aluminum one from my parts
Eng. I check the torque on the other two jugs # 4 & 7. they were ok. In another approx. 25 hours
at the Bremerton WA. form clinic the #4 cyl gasket failed completely and all 8 nuts and lock tabs
departed in flight. Only the cowling prevented #4 from departing the aircraft. I repaired it and did
not use any gasket only a new O-ring and Hymolar sealant. Found # 7 was also getting loose removed
the paper gasket and used Hymolar. Re torqued of all cyl with aluminum gaskets were tight when checked
Also used RED LOC TIGHT and lock tabs on all nuts.
I would recommend that any paper cyl base gaskets be removed. And use Hymolar and / or aluminum gaskets
Tom Elliott
CJ-6A NX63727
777 Quartz Ave
PMB 7004
Sandy Valley NV.
89019
Cell 541-297-5497
N13472(at)AOL.COM
From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Walter Lannon
Sent: Tuesday, June 18, 2019 2:29 PM
To: yak-list(at)matronics.com
Subject: Re: Re: What is the cylinder torque value for the nuts at the base.
Very true Mark;
And why I included the note that torque is a quick and dirty method. Really critical fasteners eg: the pinch bolt holding our engine crank throws in alignment, the connecting rod bolts in aircraft engines like the Merlin, hub assy. bolts in large engine propellors, etc. do not use a torque value at all.
In these and other cases the amount of bolt stretch is directly measured to a specified dimension.
However, the torque method is the basic standard and I will quote from the P & W 985/1340 Overhaul Manual “ Unless otherwise specified in this Manual all nut, bolt and screw torques should be obtained with thread lubricants”
Specifically for the cylinder flange nuts “300 lb/in with lubricant.” They do not specify a lubricant but I can assure you after 60 + years in the business it is aircraft engine oil.
300 lb./in. is the specific value. There is no need for any tolerance and none is given, The nut is locked to the stud by a simple sheet metal nut designed for this purpose called a “palnut”. No f$*(# ing around with tab washers.
The only info I have seen re: our engines is a torque table from M14P. com showing a specific 304 lb/in which I now see has been modified with a max. of 330 lb/in added. No doubt to accommodate the %&#hole tab washers.
The similarity in torque values for quite different engines is interesting but not particularly surprising. The stud size is 0.018” inches larger on our engines with a slightly coarser thread which translates to very similar thread root dia. Stud strength is likely to the same aviation standard. The major difference is simply the number of studs.
Walt
From: Mark Pennington (pennington.construction.inc.1(at)gmail.com)
Sent: Tuesday, June 18, 2019 12:15 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: Re: Re: What is the cylinder torque value for the nuts at the base.
The video I sent to Doug didn't work on the email. I have attached the link here.
Basically the video illustrates that torque is directly related to clamping force. Most torque specs that I have seen are related to a lubricated bolt or fastener. You will see that achieving a torque value does not guarantee clamping force. Clamping force is the value for a bolt or fastness in an assembly or attached part. Torque can be seen as the resistance to a nut rotational force, not tightness.
Good illustration. You can apply this information to your own work on your plane as needed.
https://www.youtube.com/watch?v=O96AUlIBkU8
Mark Pennington
N621CJ
On Tue, Jun 18, 2019 at 2:33 PM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: |
Also, from Mark Pennington, this is interesting:
https://mail.google.com/mail/u/0/?tab=rm&zx=vl5ywvgzpugl#inbox/FMfcgxwChJkxdFPJVWFSFZcLkGTCcGrW?compose=DmwnWrRnXVSjzwCjrftdqMTFtpZNSfCdPxQgNrBwDsFKJDZfWGgpgdvcrDhTRrHnqLgLwBlQDDDL&projector=1
On Tue, Jun 18, 2019 at 10:52 AM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: |
I do believe the question was asked but maybe missed by some of us.
What is "wet" torque? What exactly does this mean? If I interpret the cut n past from the net correctly then torquing the cly base studs to 304 to 330 inch pounds WET is way excessive.
From :https://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html
When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below.
Lubricant
Torque Reduction
(%)
No lube
0
Graphite
50 - 55
White Grease
35 - 45
SAE 30 oil
35 - 45
SAE 40 oil
30 - 40
On Tue, Jun 18, 2019 at 3:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
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n13472(at)aol.com
Guest
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| Posted: Tue Jun 18, 2019 2:51 pm Post subject: What is the cylinder torque value for the nuts at the base. |
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It is not offset. It is on axis with the box end wrench.
Tom Elliott
CJ-6A NX63727
777 Quartz Ave
PMB 7004
Sandy Valley NV.
89019
Cell 541-297-5497
N13472(at)AOL.COM
From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Mark Pennington
Sent: Tuesday, June 18, 2019 2:58 PM
To: yak-list(at)matronics.com
Subject: Re: Re: What is the cylinder torque value for the nuts at the base.
Walt
I agree torque is the normal standard and every race engine that I assembled along the way used a little product called "Assembly Lube" apply the lube before the tightening phase of assembly. I am sure motor oil on our engines is the standard as you suggest. I don't have the experience you have by far. I have used the same oil I put in the crank case of the M14 when I assemble things.
Question: I understand the nut welded to the special tool for the cylinder head nuts. Does that provide an accurate torque value being offset like it is. ? Or in your experience is the difference negligible? I can see it would give you consistency for sure.
And yes, I will be checking my cylinder head nuts the next time both cowls are off. I had contacted Dennis and he said the same thing, weld a nut to your tool......... Thanks for all of the good info..
Learn something new everyday.
Mark
On Tue, Jun 18, 2019 at 5:34 PM Walter Lannon <wlannon(at)shaw.ca (wlannon(at)shaw.ca)> wrote:
| Quote: |
Very true Mark;
And why I included the note that torque is a quick and dirty method. Really critical fasteners eg: the pinch bolt holding our engine crank throws in alignment, the connecting rod bolts in aircraft engines like the Merlin, hub assy. bolts in large engine propellors, etc. do not use a torque value at all.
In these and other cases the amount of bolt stretch is directly measured to a specified dimension.
However, the torque method is the basic standard and I will quote from the P & W 985/1340 Overhaul Manual “ Unless otherwise specified in this Manual all nut, bolt and screw torques should be obtained with thread lubricants”
Specifically for the cylinder flange nuts “300 lb/in with lubricant.” They do not specify a lubricant but I can assure you after 60 + years in the business it is aircraft engine oil.
300 lb./in. is the specific value. There is no need for any tolerance and none is given, The nut is locked to the stud by a simple sheet metal nut designed for this purpose called a “palnut”. No f$*(# ing around with tab washers.
The only info I have seen re: our engines is a torque table from M14P. com showing a specific 304 lb/in which I now see has been modified with a max. of 330 lb/in added. No doubt to accommodate the %&#hole tab washers.
The similarity in torque values for quite different engines is interesting but not particularly surprising. The stud size is 0.018” inches larger on our engines with a slightly coarser thread which translates to very similar thread root dia. Stud strength is likely to the same aviation standard. The major difference is simply the number of studs.
Walt
From: Mark Pennington (pennington.construction.inc.1(at)gmail.com)
Sent: Tuesday, June 18, 2019 12:15 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: Re: Re: What is the cylinder torque value for the nuts at the base.
The video I sent to Doug didn't work on the email. I have attached the link here.
Basically the video illustrates that torque is directly related to clamping force. Most torque specs that I have seen are related to a lubricated bolt or fastener. You will see that achieving a torque value does not guarantee clamping force. Clamping force is the value for a bolt or fastness in an assembly or attached part. Torque can be seen as the resistance to a nut rotational force, not tightness.
Good illustration. You can apply this information to your own work on your plane as needed.
https://www.youtube.com/watch?v=O96AUlIBkU8
Mark Pennington
N621CJ
On Tue, Jun 18, 2019 at 2:33 PM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: |
Also, from Mark Pennington, this is interesting:
https://mail.google.com/mail/u/0/?tab=rm&zx=vl5ywvgzpugl#inbox/FMfcgxwChJkxdFPJVWFSFZcLkGTCcGrW?compose=DmwnWrRnXVSjzwCjrftdqMTFtpZNSfCdPxQgNrBwDsFKJDZfWGgpgdvcrDhTRrHnqLgLwBlQDDDL&projector=1
On Tue, Jun 18, 2019 at 10:52 AM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: |
I do believe the question was asked but maybe missed by some of us.
What is "wet" torque? What exactly does this mean? If I interpret the cut n past from the net correctly then torquing the cly base studs to 304 to 330 inch pounds WET is way excessive.
From :https://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html
When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below.
Lubricant
Torque Reduction
(%)
No lube
0
Graphite
50 - 55
White Grease
35 - 45
SAE 30 oil
35 - 45
SAE 40 oil
30 - 40
On Tue, Jun 18, 2019 at 3:56 AM A Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
Archive Search & Download, 7-Day Browse, Chat, FAQ,
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Cliff.Coy
Joined: 03 Mar 2007
Posts: 46
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| Posted: Wed Jun 19, 2019 8:58 am Post subject: What is the cylinder torque value for the nuts at the base. |
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The torques are for clean and dry threads.
Please reference the M14-P Overhaul Manual Pg.142-143.
The Manual is available here: http://motorstarna.com/m-14p-overhaul-manual
Overtorque of the nuts will increase the chance of the studs pulling from the crankcase leading to further leakage.
Cliff
On Tue, Jun 18, 2019 at 2:33 PM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: | Also, from Mark Pennington, this is interesting:https://mail.google.com/mail/u/0/?tab=rm&zx=vl5ywvgzpugl#inbox/FMfcgxwChJkxdFPJVWFSFZcLkGTCcGrW?compose=DmwnWrRnXVSjzwCjrftdqMTFtpZNSfCdPxQgNrBwDsFKJDZfWGgpgdvcrDhTRrHnqLgLwBlQDDDL&projector=1
On Tue, Jun 18, 2019 at 10:52 AM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: | I do believe the question was asked but maybe missed by some of us.What is "wet" torque? What exactly does this mean? If I interpret the cut n past from the net correctly then torquing the cly base studs to 304 to 330 inch pounds WET is way excessive.
From :https://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html
When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below.LubricantTorque Reduction
(%)No lube0Graphite50 - 55White Grease35 - 45SAE 30 oil35 - 45SAE 40 oil30 - 40
On Tue, Jun 18, 2019 at 3:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
Archive Search & Download, 7-Day Browse, Chat, FAQ,
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--
Clifford Coy
Border Air Ltd.
C-Parts Inc.
629 Airport Rd.
Swanton, VT 05488
802-868-2822 TEL
802-868-0035 FAX (MANUAL RECEIVE)
Skype: Cliff.Coy
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wlannon(at)shaw.ca
Guest
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| Posted: Wed Jun 19, 2019 8:06 pm Post subject: What is the cylinder torque value for the nuts at the base. |
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Thanks Cliff;
The Overhaul manual section you reference certainly confirms the torque value of 304 lb/in. It does not support the maximum of 330 lb/in we have seen recently from other sources.
It does not however address the question of dry or lubed and makes no recommendation in this area that I could find.
Agreed that over torque must be avoided but I would suggest that under rather than over torque is the most likely cause of loose studs. Consider that, at the correct torque, the studs are stretched within the elastic limit and as such are providing a downward load on the cylinder flange. Lets call that load 2400 lbs. With each combustion event in the cylinder the upward load (call it 2200 lbs.) is fully reacted with no resulting cylinder movement.
If the studs have been over-torqued and stretched beyond the elastic limit that 2400 buffer load is drastically reduced and broken studs are the likely result
as the over-torque has probably introduced microscopic cracking.
In the event of under torque the result is similar, The buffer load is not adequate to contain the cyclic combustion loading. Loose, cracked or broken studs will be the result.
I think under is the most likely scenario since anything placed under the flange or under the nut that is
softer than the steel flange is going to degrade the
joint and will eventually cause a problem. Including
tab washers!
Re dry or lubed it would be interesting to see the M 462 RF Overhaul Manual.
Walt
To: yak-list (yak-list(at)matronics.com) Subject: Re: Re: What is the cylinder torque value for the nuts at the base.
The torques are for clean and dry threads.
Please reference the M14-P Overhaul Manual Pg.142-143.
The Manual is available here: http://motorstarna.com/m-14p-overhaul-manual
Overtorque of the nuts will increase the chance of the studs pulling from the crankcase leading to further leakage.
Cliff
On Tue, Jun 18, 2019 at 2:33 PM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: | Also, from Mark Pennington, this is interesting: https://mail.google.com/mail/u/0/?tab=rm&zx=vl5ywvgzpugl#inbox/FMfcgxwChJkxdFPJVWFSFZcLkGTCcGrW?compose=DmwnWrRnXVSjzwCjrftdqMTFtpZNSfCdPxQgNrBwDsFKJDZfWGgpgdvcrDhTRrHnqLgLwBlQDDDL&projector=1
On Tue, Jun 18, 2019 at 10:52 AM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: | I do believe the question was asked but maybe missed by some of us. What is "wet" torque? What exactly does this mean? If I interpret the cut n past from the net correctly then torquing the cly base studs to 304 to 330 inch pounds WET is way excessive.
From :https://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html
When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below. Lubricant Torque Reduction
(%) No lube 0 Graphite 50 - 55 White Grease 35 - 45 SAE 30 oil 35 - 45 SAE 40 oil 30 - 40
On Tue, Jun 18, 2019 at 3:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
Archive Search & Download, 7-Day Browse, Chat, FAQ,
http://ww==================
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|
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--
Clifford Coy
Border Air Ltd.
C-Parts Inc.
629 Airport Rd.
Swanton, VT 05488
802-868-2822 TEL
802-868-0035 FAX (MANUAL RECEIVE)
Skype: Cliff.Coy
Virus-free. www.avast.com [url=#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2] [/url]
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GeorgeCoy
Joined: 02 Dec 2010
Posts: 310
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| Posted: Fri Jun 21, 2019 4:44 am Post subject: What is the cylinder torque value for the nuts at the base. |
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OI have confirmed with the factory that the tightening torque of the nuts that holds the cylinders to crankcase is 3.5 Kgf-m or 304 lbf-in. The threads have to be clean and dry.
George Coy
From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Cliff Coy
Sent: Wednesday, June 19, 2019 12:57 PM
To: yak-list <yak-list(at)matronics.com>
Subject: Re: Re: What is the cylinder torque value for the nuts at the base.
The torques are for clean and dry threads.
Please reference the M14-P Overhaul Manual Pg.142-143.
The Manual is available here: http://motorstarna.com/m-14p-overhaul-manual
Overtorque of the nuts will increase the chance of the studs pulling from the crankcase leading to further leakage.
Cliff
On Tue, Jun 18, 2019 at 2:33 PM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: |
Also, from Mark Pennington, this is interesting:
https://mail.google.com/mail/u/0/?tab=rm&zx=vl5ywvgzpugl#inbox/FMfcgxwChJkxdFPJVWFSFZcLkGTCcGrW?compose=DmwnWrRnXVSjzwCjrftdqMTFtpZNSfCdPxQgNrBwDsFKJDZfWGgpgdvcrDhTRrHnqLgLwBlQDDDL&projector=1
On Tue, Jun 18, 2019 at 10:52 AM doug sapp <dougsappllc(at)gmail.com (dougsappllc(at)gmail.com)> wrote:
| Quote: |
I do believe the question was asked but maybe missed by some of us.
What is "wet" torque? What exactly does this mean? If I interpret the cut n past from the net correctly then torquing the cly base studs to 304 to 330 inch pounds WET is way excessive.
From :https://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html
When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below.
Lubricant
Torque Reduction
(%)
No lube
0
Graphite
50 - 55
White Grease
35 - 45
SAE 30 oil
35 - 45
SAE 40 oil
30 - 40
On Tue, Jun 18, 2019 at 3:56 AM A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
| Quote: |
Matt,
A torque spec is there for a reason. The "feels about right" spec is not in the spec sheet. Over-torquing is definitely not a good thing. You may want to reconsider your torquing technique in the future.
The M14 torque specs are no where near 35 ft/lbs. That is actually 25% more than the high end of the spec. The torque specs are as posted on this subject.
Dennis
On Tuesday, June 18, 2019, 1:57:39 AM EDT, woodja51 <mwuillemin(at)mac.com (mwuillemin(at)mac.com)> wrote:
--> Yak-List message posted by: "woodja51" <mwuillemin(at)mac.com (mwuillemin(at)mac.com)>
I bought an electronic torque wrench that beeps when you get close to and the again when at the correct torque. And used the Chinese spanner with it attached. I took my nuts up on paper gaskets ( there are aluminium ones there it seems as standard ?) to 35 ‘ lbs which is closer to the values on the m14 I think. They should always be wet/ lubed for torque setting I believe. I might have slightly over torqued them but would rather be a little in the high side. Matt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489701#489701
Archive Search & Download, 7-Day Browse, Chat, FAQ,
http://ww==================
http://forums.matronics.com
http://www.matronics.com/contr========================
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--
Clifford Coy
Border Air Ltd.
C-Parts Inc.
629 Airport Rd.
Swanton, VT 05488
802-868-2822 TEL
802-868-0035 FAX (MANUAL RECEIVE)
Skype: Cliff.Coy
| | - The Matronics Yak-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
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woodja51
Joined: 13 May 2015
Posts: 40
Location: MELBOURNE AUSTRALIA
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| Posted: Sun Jun 23, 2019 2:21 am Post subject: Re: What is the cylinder torque value for the nuts at the b |
|
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Agreed , specs exist for a reason ..I was talking about a Housai actually and based on the torque (I) required to break the nuts I was removing at overhaul , as these seemed pretty dang tight and required heat to loosen. I broke a Chinese nut spanner in the process actually ( split it ) The sub-30 values seemed just too light. Also , given most really accurate torques are multi step / angular or stretch based my gut feeling is that with paper gaskets ( which is what China provided ) , wet torqued ( engine oil ) compared to the dry clean M14 system maybe is why there is a difference in values / technique ? Any stress fastener engineer thoughts appreciated. I guess I will see how the overhauled engine goes once I eventually install it I thought about loctite too but my LAME said a waste of time for that situation given they are lock tabbed too. But I’m no expert of course just plugging into the forum. Of course a better/ good idea might have been to also replace the studs too but this engine was overhauled due to a supercharger failure and none of the nuts / studs were loose at all. This was a 300 hour since overhaul engine where the blower disintegrated in flight FYI
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