[Note: Updated this post to include the calculator tool - just download and click on the formula you want to use- requires spreadshheet program compatible with microsoft .xls format]
Thought I would share some findings on the amount of force generated on the main gear shaft for a conventional reel. This is useful for determining the amount of force on the anti-reverse mechanism (dogs or AR bearings), as well as the main gear and handle shaft.
Opinions/corrections are welcome.
1. Here is the formula:
R: radius (not diameter) of spool including line
F: Force (drag setting at reel)
G: gear ratio
Torque = R*F*G
Simple enough.
2. Example: Let's apply this to a popular size small to medium saltwalter reel sized reel. Let's say we have a reel spool filled with line to a 1.25 inch radius (2.5 inch diameter) a 8 lb drag setting, and a 5:1 gear ratio.
Torque (lb-in) = 1.25*8*5 = 50
It is probably more useful to translate the torque number to more common units:
lb-ft (AKA ft-lb) = lb-in/12 = 50/12 = 4.1667
N.m. = lb-ft* 1.35582 = 4.1667* 1.35582 = 5.6493
3. Lets look up some one-way bearings for fishing reels on the Boca site: For shaft sizes 10-12 mm- we are looking at a range of 2- 6 Nm, depending on the bearing. If we want a bearing capable of handling more- we need to have a shaft size of 14mm- where they move up into 15+ Nm ratings
4. Observations:
a. These are theoretical numbers- any friction in the system will decrease the torque some, but it should be close enough for or our purposes.
b. Anyone familiar with using a torque wrench will recognize that the amount of force being applied on the anti-reverse mechanism of a typical reel is relatively small. These components fail because of design choices, not unmanageable load for the reel's basic dimensions.
Agree/disagree?
-J
Since I didn't understand a word I agree. I can't add 2 and 2 without making a mistake. I know you are being serious but my trying to make sense makes my eyes glaze over. Dominick
The line doesn't stay at the same place on the spool when fishing. Just to name a few: boat speed, wind conditions, type of line used, type of rod and position of that rod all come into play. There are other factors to take in consideration, you could get close but that's about it.
Most manufacturer will mark line retrieve on their new reel boxes, lets say line retrieve is 34" per crank, but they don't tell you where the line sits on the spool when getting that number. Those figures are worthless to me, as soon as you drop a couple hundred feet of line in the water, those figures go with it...just my opinion.
Quote from: Alto Mare on May 23, 2015, 11:09:42 PM
The line doesn't stay at the same place on the spool when fishing. Just to name a few: boat speed, wind conditions, type of line used, type of rod and position of that rod all come into play. There are other factors to take in consideration, you could get close but that's about it.
Most manufacturer will mark line retrieve on their new reel boxes, lets say line retrieve is 34" per crank, but they don't tell you where the line sits on the spool when getting that number. Those figures are worthless to me, as soon as you drop a couple hundred feet of line in the water, those figures go with it...just my opinion.
I agree that real field observations beat calculations, but sometimes the calculations will help you find out things that take too much trial and error otherwise.
As the spool decreases the drag setting goes up accordingly, so I think these even out. boat/wind/current speed, rod angle etc. affect the pressure that the fish may feel, but not the maximum torque on the dogs/ one-way bearing/gear sleeve to handle junction, etc. This is controlled by the drag setting.
I will give you a few examples of usefulness.
1. If someone wanted to add an aftermarket one-way bearing to a reel- this would help them determine the specifications for the bearing.
2. For the Baja Special dog enhancement you are working on- you could have Lee cut you out a bridge sleeve to hex-head adapter. I think you could bolt the bridge assembly to a work bench. use a torque wrench and observe the amount much reverse pressure it takes before the dogs start tweaking when the sleeve is aligned, tilted out of alignment etc. You can convert the torque number to an approximate drag setting with the posted formula. You can compare any improvements you make against this the same way. It will not 100% prove that it will be fixed in the field, but it might make the process of getting to the right solution faster.
(BTW- I think the Baja Special dog/ratchet project is a great idea. It can most likely be a component level fix, and should apply to the US Senator line as well.)
3. It helps provide me some sense of the amount of force on the reel components. The changes in manufacturing and materials capabilities allow for some new designs that could meet these forces without overbuilding the reel as is done today. This also applies to reel modifications, but to a lesser extent. For example, it shows that the dog/ratchet assembly on the Baja Special should be able able to withstand much greater pressure than it does today, as long as the components can be kept in alignment.
This of course presumes that my math is correct- always a risky proposition :)
Quote from: jurelometer on May 23, 2015, 11:53:11 PM
This of course presumes that my math is correct- always a risky proposition :)
I applied your formula and logic to the max drag results George got using the same 5+1 drag stacks on two 349s with different gear ratios, 349 (2:1) 29 lbs & 349H (3.25:1) 18 lbs. http://alantani.com/index.php?topic=4983.0 (http://alantani.com/index.php?topic=4983.0)
Assuming both had 1.25" of line (around 1/2" from the lip of the spool) the amount of torque the drags could hold before slipping on each reel is;
349) 1.25*29*2.1 = 76 lb/in or 6.3 lb/ft or 8.6 Nm
349H) 1.25*18*3.25 = 73 lb/in or 6.1 lb/ft or 8.2 Nm
Pretty close given the variables.
Like you said - a torque wrench would be a quick bench test of modifications, using the formula to calculate a ball park figure of what torque will be generated.
Well if you are lost a Radio might help if it is a 2 way. ;D ;D ;D
I feel my chain getting yanked ;) But this stuff isn't that tricky.
Torque is just rotational force applied at a distance from the center. So if we are applying 8 lbs of drag with the line one inch from the center of the spool, we are applying 8lb-in of torque. Gears provide a mechanical multiplier so we have to multiply by the gear ratio. Now divide by the number of inches in a foot (err... 12). Now we have ft-lbs of torque (units on your torque wrench) based on reel type and drag setting. Piece of cake.
If you have ever tightened a bolt with a torque wrench, you will know that a couple of ft-lbs of torque is not very much force. That should be useful info for all the folks customizing dog and one-way bearing setups. Also, since upping the gear ratio increases the torque, the same star drag reel will have less total drag capacity with a higher gear ratio, etc., etc.
Quote...the amount of force being applied on the anti-reverse mechanism of a typical reel is relatively small. These components fail because of design choices, not unmanageable load for the reel's basic dimensions.
Agree/disagree?
I didn't bother to check the math or anything, but it sounded about right.
Agree. I don't know offhand what force is required to, for example, break a Senator dog, but it is a lot. Many, many times over what the drag / line is capable of. In the case of one-way bearings, yes-- this is absolutely an important design consideration. This, along with wear. I met a design engineer at another company, and we started talking about unforeseen wear and real-world circumstances of the life of a trolling reel. He was wondering what would happen if a boat was trolling a lure that skipped across waves, all day long, every day, every month, for years. pull, skip, pull, skip, yank, stop, yank, stop... so he put an antireverse mechanism in his CNC machine and programmed it to do a yank/stop cycle one million times. it took a couple of weeks. (The mechanism held. He didn't say what it looked like)
Not entirely unrelated earlier thread: http://alantani.com/index.php?topic=4589.msg35751#msg35751
.
Jurelometer
I hope you don't think I was yanking your chain? I agree with you, it's not that tricky, the formula explains very well, and simply, why the same drag configuration gives different max drag with different gear ratios and diameter of line on the spool. It lines up very well with George's observations when he tested his 349s for max drag.
I have recently added a couple of modified dogs and dog posts to a couple of 349 bridges using very basic tools and techniques, hence my interest and reference to 349s and max drag. I am not all that confident with my posts in particular. With your calculation, I can now screw the bridge down and test each post and dog to the max torque that I can expect/want on the gear sleeve for the target max drag, before assembling the reel and doing any practical tests of the complete system.
For example; if I think I can find a drag set up that will provide 30 lbs on a 349H with a full spool, the calculation is;
1.5*30*3.25 = 146 lb/in or 12.2 lb/ft or 16.5 Nm.
Then, using a factor of safety of 2, the dogs and posts will need to withstand ~ 30 Nm. If they do pass the test and the reel fails practical tests later, it will not be the dogs or posts that caused it.
I'm going to find a torque wrench and try it.
Dave, you're a very smart man, I got that from the very first time I talked to you. Thank you for doing these figures for us. Calculations will get you close, but you will still need to use it on the field.
When doing upgrades, we take a short cut here, we already know that most of the vintage reels we upgrade have been made stronger than expected and some have been in service for well over 70 years, Penn already did the hard work for us.
This was a big achievement on their part and I personally believe that it won't happen with the newer models of today.
This is one of the reason we like to invest in those.
Sal
This post is more important that most realize...not for the mechanical dogs so much as I think they are far stronger than they need to be. The case of the Baja Special is a different one as the ratchet and dogs are "tippy" and can be slightly out of axis when they engage as well as the teeth being particularly fine and sharp meaning they have less handle back play but can "bite" the dog.
With AR Beaings however, we see them fail often as they are on the handle side and the gear train (closer to 6:1 in most recent reels) multiplies that force considerably. Combine that with 15lbs of drag and you end up with 90lbs on the bearing. Most are not "rated" for this load and really only function reliably due to their having a "safety margin" over their rating (typically 100% or more).
This is why so many fail in conjunction with corrosion due to their exposed position in the handle in conventional reels. A little corrosion, a hesitation to bite plus a force greater than the bearing is designed to manage and the handle goes knuckle buster.
This is why they all have back up dogs now.
As well, the AR Bearing being placed in the handle so that the gear train experiences the forces first causes unnecessary wear, whereas for example in a spinning reel they spare the gear train all force (unless you try and crank against the pressure) as they stop rotation before the gear train experiences it.
Final upshot: In a conventional reel the handle side is the convenient place for an ARB but they are highly stressed there due to the effects of gearing and exposed to corrosion. Understanding the forces is key to understanding why back up dogs are there.
MHC: sorry- didn't want to include you with the chain-yankers. I am curious as to how you plan to attach the torque wrench to the bridge sleeve. Btw - I think you skipped a step in your unit conversions for the 349- the Nm number should be much lower.
Also an interesting question- what kind of torque measurement tool is reasonably accurate at these low settings. Not sure I would trust the one that sets my lug nuts.
Reel224: all in fun. Does my head look that pointy? Honest- it's just the hair ;D. If you just want to know the drag setting, use a drag scale on the line. This is more about the forces on the other end of the system.
Robert: thanks- some interesting data. I think that the Q in the post you referenced was really about force and not torque. The easy answer would have been use a scale on the handle and then adjust for new handle length.
Sal: agree with everything except the "smart" part :). The testing and innovations you have contributed to us all are the basis for some of my ideas. The classic Penns have a consistent design that was effective for the customer usage and manufacturing methods of the 1930s. 80 years later these are still viable reels with some part upgrades. I think the key to getting a better dog system is to keeping the parts flat and aligned- this is what the numbers tell us, and this is where the baja special design is "challenged".
John: agree. I am curious as to the effect of slipping on one-way bearings in terms of longevity. Also, if stacking one way bearings really distributes the load evenly. Since the inner race has to jiggle and rotate for the bearing to lock, it would seem that only the first one to grab would lock completely...
MHC: Just thought of something. You could use a crescent wrench and a spring pull scale for measuring the torque at the gear sleeve. Just stick the scale hook in the hole in the cresent wrench. Divide the force by the distance of the lever.
Anybody looking for a serious upgrade, should consider one of these. Max torque 8450 Nm ;D
Regards
Mark
Quote from: jurelometer on May 24, 2015, 05:16:21 PM
Btw - I think you skipped a step in your unit conversions for the 349- the Nm number should be much lower.
Correct, I skipped lb/inch to lb/ft and have now fixed it thanks - no really, it is a simple calculation ;D ;D
I haven't got round to thinking about the torque wrench connection, but I like your idea of a wrench and pull scale for the low torque.
Quote from: Reel 224 on May 25, 2015, 01:21:52 AM
Jurelometer: I was being serious with my second post, it was a question more then a comment. As far as the torque wrench is concerned it would be one that is calibrated in inch Lbs. Your knowledge in the theory of force applied to the drive gears is beyond my knowledge, and I'm more then happy to admit that. As I said you are supporting knowledge to this site that I can appreciate even though it will never be of much importance to me personally. If my question or comments did offend you I do apologize, they were not meant to at all.
No offense whatsoever- all in fun. Rib away!
Quote from: MFB on May 24, 2015, 07:39:19 PM
Anybody looking for a serious upgrade, should consider one of these. Max torque 8450 Nm ;D
Regards
Mark
Well that would be handy for stump pulling :)....
Quote from: Reel 224 on May 24, 2015, 04:31:44 AM
No disrespect intended, but I agree with Dominick.....for once. You guys have to much free time on your hands.You guys need to take into consideration the variables that come to play in force = resistance+Radios< > * distance Etc. Now I'm lost ??? :o
i've been chuckling at this the whole time! i have to agree, you guys do have too much time on your hands! ;D
I actually thought it was very interesting, not for me though, I use old reliable gear, wagon and bricks ;D. This type of thing would sure help improve some of the new gear available today.
Sal
Quote from: alantani on May 25, 2015, 04:25:23 PM
Quote from: Reel 224 on May 24, 2015, 04:31:44 AM
No disrespect intended, but I agree with Dominick.....for once. You guys have to much free time on your hands.You guys need to take into consideration the variables that come to play in force = resistance+Radios< > * distance Etc. Now I'm lost ??? :o
i've been chuckling at this the whole time! i have to agree, you guys do have too much time on your hands! ;D
Et tu Brute ;D.
But seriously, This stuff should be of practical use to more than a few of us. I could crank out a spreadsheet that would take the spool diameter and gear ratio as input and would output a one-way bearing rating, or input a bearing rating and the reel dimensions, output the max drag before the bearing exceeded the specs. But not sure how I could post it. I don't want to go through the work to code up some php and host a web page. That would definitely support the "too much time on your hands" argument. :P
Ok, off to make some reel parts now. Will try to use as little science as possible :) :) :)
-J
I tried the crescent wrench with a pull scale on two 349 bridges I have modified with two extra dog posts.
(https://lh3.googleusercontent.com/-u9CaX36K6Io/VXPVFzIp68I/AAAAAAAAAdk/75-zynHrx6M/s800/DSCF2476.JPG)
My target was 30 lb drag with a 349H gear ratio of 3.25 to one & full spool. Worked out to be 146 lb/in.
The crescent wrench is 5.25 inch from the centre of the gear sleeve to the hole at the end of the handle where the scale attaches.
146/5.25 = 28lb
I screwed the bridge to a block of wood tried loading the dogs one at a time to 30 lb.
(https://lh3.googleusercontent.com/-wLV3nlZNqPU/VXPVddMlqaI/AAAAAAAAAds/WkTZPgyDock/s800/DSCF2475.JPG)
The first two posts and dogs on bridge 1 were OK to 35 lb. The third post was too close to the edge of the bridge and tilted outwards, this raised the dog and the tip causing the dog and gear sleeve ratchet to fail;
(https://lh3.googleusercontent.com/-x0pbCmSSuFg/VXPnYG1SmmI/AAAAAAAAAfU/698GMuC_4Ko/s800/DSCF2481.JPG)
(https://lh3.googleusercontent.com/-S_y4TFZvfJ8/VXPeiugV5MI/AAAAAAAAAe8/Fd_jV4JDDbw/s800/DSCF2465.JPG)
(https://lh3.googleusercontent.com/-v_NWU6k3ces/VXPep-6SWNI/AAAAAAAAAfE/nCoZK2kooxo/s800/DSCF2460.JPG)
I then tried bridge 2 with stainless dogs and gear sleeve. The three posts stood up to around 35 lb but one of my modified dogs started to bend at around 20 lb and failed at 25 lb.
The bent dog is on top in the photo, The back edge started out the same shape as the bottom dog & I had ground out the other side trying to make more room for a spring on a third dog.
(https://lh3.googleusercontent.com/-FHthBIBH9P0/VXPV1fI72UI/AAAAAAAAAd0/oGw1bkjfRWg/s800/DSCF2477.JPG)
I'm glad I tried this, thanks for the idea jurelometer.
Interesting test and results. Seems like the dog pins that are supported on both ends (sideplate and bridge), as well as those that are mounted further inboard on the bridge should be able to stand up to greater forces. Looks like it is important for the entire edge, and as much surface as possible, to squarely and cleanly align with the ratchet teeth in order to maintain maximum strength. I think I may start being a bit more fastidious with regards to replacing dogs showing any noticable signs of uneven wear or marring.
Nice test! I'm not taking anything way, I thank you for doing this.
I believe you would have had different results if the main gear was in place and the star cranked down. I understand this isn't a drag test, but the gear would have helped keeping the dogs in place.
It appears that the dogs lifted and slipped from the top of the ratchet, something that wouldn't happen in the real world.
Sal
Thanks Sal,
I agree - a gear held in place, with the pressure needed to give the 30 lb drag the test was based on, would probably have stopped the dog from lifting to the point where it slipped. That would have saved the sleeve and dog from the damage they experienced in this test. I was thinking how to do this and still be able to put a wrench on the sleeve and now, after the test, think a metal sleeve with cut out sections on each side to fit the wrench in would work - next time.
The main reason I did this was to test the dog posts (and dogs) I had installed, I was concerned the 3rd posts were too close to the edge of the bridge. The test showed me the post on bridge 1 was too close, if you look at the 3rd photo above you can see the edge of the bridge is deformed - it wasn't before the test. The 3rd post on the 2nd bridge was only a 1/16th or so further in from the edge but held up fine. It also showed me long curved skinny dogs aren't strong - even with stainless. The Penn brass and Lee's dogs were both fine.
Tightlines666 makes a good point - the contact between the dog and ratchet teeth should be as complete as possible to evenly spread the load, particularly with higher drag settings.
Michael
Quote from: mhc on June 07, 2015, 12:26:26 PM
Thanks Sal,
I agree - a gear held in place, with the pressure needed to give the 30 lb drag the test was based on, would probably have stopped the dog from lifting to the point where it slipped. That would have saved the sleeve and dog from the damage they experienced in this test. I was thinking how to do this and still be able to put a wrench on the sleeve and now, after the test, think a metal sleeve with cut out sections on each side to fit the wrench in would work - next time.
The main reason I did this was to test the dog posts (and dogs) I had installed, I was concerned the 3rd posts were too close to the edge of the bridge. The test showed me the post on bridge 1 was too close, if you look at the 3rd photo above you can see the edge of the bridge is deformed - it wasn't before the test. The 3rd post on the 2nd bridge was only a 1/16th or so further in from the edge but held up fine. It also showed me long curved skinny dogs aren't strong - even with stainless. The Penn brass and Lee's dogs were both fine.
Tightlines666 makes a good point - the contact between the dog and ratchet teeth should be as complete as possible to evenly spread the load, particularly with higher drag settings.
Michael
Good job! And thanks for sacrificing some parts to educate the rest of us. A little mechanical engineering, a little bench testing, a little real world experience- all from different viewpoints. this is what I like!
I would think that you could add on the whole gear/drag assembly with the exception of the spacer sleeve. Tighten the drag down to the same level as when the reel is set to the target drag. There should be room to slip a small wrench onto the shaft. This is closer to real life, and a more useful the simulation as others have pointed out. Having the plate on the bench allows you to see what is probably happening inside the reel. It is probably worthwhile to know if the failure will be due to dog mis-alignment or pin bending.
If you want to estimate the force on the pin and or dog, multiply the torque on the the main shaft in lb-in by the distance (radius) from the center of the ratchet to the center of the ratchet tooth engagement with the dog.
Regarding the sync vs async multi-dog question- I have been hesitating to dive into religion, but here goes the mechanical aspects:
1. Synchronized dogs do not generally share load until something bad starts to happen. The pin/dog/ratchet system is not very elastic- so the first dog takes all the force until it starts to fail. Once it starts to fail the second dog will take a over the load- with potentially some sharing, depending on the damage
You don't get the benefit of the second dog until the first dog is overloaded. But at that point you have a better chance of all of the parts still being in place, so the reel can still function.
2. Asynchronous dogs will give you less handle backplay, but when a dog fails- it is much worse. It will fail more completely, and there will be greater impact force on the second dog as the ratchet goes flying backward. More chances of the second dog blowing out or having the first dog remnants jamming the reel.
If I was designing a reel from scratch, I would design the dogs to handle the max load, and make them asynchronous. If I was customizing a reel it is a bit trickier, and to some extent, depends on my goal.
I'm going to try to attach a calculator. It is a Word document with embedded worksheets. click on the worksheet and modify the cells in yellow to match your reel specs. Let me know if this works.
-J.
Quote from: jurelometer on June 07, 2015, 11:06:45 PM
Regarding the sync vs async multi-dog question- I have been hesitating to dive into religion, but here goes the mechanical aspects:
1. Synchronized dogs do not generally share load until something bad starts to happen. The pin/dog/ratchet system is not very elastic- so the first dog takes all the force until it starts to fail. Once it starts to fail the second dog will take a over the load- with potentially some sharing, depending on the damage
You don't get the benefit of the second dog until the first dog is overloaded. But at that point you have a better chance of all of the parts still being in place, so the reel can still function.
2. Asynchronous dogs will give you less handle backplay, but when a dog fails- it is much worse. It will fail more completely, and there will be greater impact force on the second dog as the ratchet goes flying backward. More chances of the second dog blowing out or having the first dog remnants jamming the reel.
If I was designing a reel from scratch, I would design the dogs to handle the max load, and make them asynchronous. If I was customizing a reel it is a bit trickier, and to some extent, depends on my goal.
I'm going to try to attach a calculator. It is a Word document with embedded worksheets. click on the worksheet and modify the cells in yellow to match your reel specs. Let me know if this works.
-J.
Dave, I disagreed with you about this earlier and I'm going to disagree with you again ;D. The way a fishing reel is designed, with dogs and ratchet, having the dogs engage at the same time, the force will be shared by both.
I do not believe that one of the dog gets most of the load, unless that dog engages a little earlier than the other.
This would definitely be a good test to see if I'm right or the formula is, but I already have a bucket full of damaged parts, so I let someone else prove me wrong.
Sal
Interesting comments on the sync V async dogs issue. With the long curved skinny dog that bent during the test, a second dog close to being in sync might have saved it - which is what you said. The first to take the load needs to flex or deform before the second takes some of the load. The amount of flex or deformation needed would depend on how close the dogs are to being perfectly synchronized.
The link & spreadsheets work fine - thanks. Should the force on the dogs calculated in the third sheet be the torque divided by the radius ie; decreasing as the radius increases for a given torque?
Quote from: Alto Mare on June 08, 2015, 12:29:12 AM
Quote from: jurelometer on June 07, 2015, 11:06:45 PM
Regarding the sync vs async multi-dog question- I have been hesitating to dive into religion, but here goes the mechanical aspects:
1. Synchronized dogs do not generally share load until something bad starts to happen. The pin/dog/ratchet system is not very elastic- so the first dog takes all the force until it starts to fail. Once it starts to fail the second dog will take a over the load- with potentially some sharing, depending on the damage
You don't get the benefit of the second dog until the first dog is overloaded. But at that point you have a better chance of all of the parts still being in place, so the reel can still function.
2. Asynchronous dogs will give you less handle backplay, but when a dog fails- it is much worse. It will fail more completely, and there will be greater impact force on the second dog as the ratchet goes flying backward. More chances of the second dog blowing out or having the first dog remnants jamming the reel.
If I was designing a reel from scratch, I would design the dogs to handle the max load, and make them asynchronous. If I was customizing a reel it is a bit trickier, and to some extent, depends on my goal.
I'm going to try to attach a calculator. It is a Word document with embedded worksheets. click on the worksheet and modify the cells in yellow to match your reel specs. Let me know if this works.
-J.
Dave, I disagreed with you about this earlier and I'm going to disagree with you again ;D. The way a fishing reel is designed, with dogs and ratchet, having the dogs engage at the same time, the force will be shared by both.
I do not believe that one of the dog gets most of the load, unless that dog engages a little earlier than the other.
This would definitely be a good test to see if I'm right or the formula is, but I already have a bucket full of damaged parts, so I let someone else prove me wrong.
Sal
We are in agreement that the second dog cou;d kick in at some point well before catastrophic failure. The damage may be so insignificant that we could categorize is it as "settling in".
It is virtually impossible to machine ( not to mention die, laser, or water jet cut) a synchronous multi-dog/ratchet system that is so accurate that both dogs will contact the ratchet at exactly the same moment. So now we are relying on something to give way for the load to be shared. The dogs are not going to compress and expand. If a particular reel is elastic at this location (e.g. a bridge plate or dog pin that flexes a bit under load)- then you may begin to get some load sharing before any damage or wear of significance occurs -Notice that I am I am cleverly backtracking a tiny bit here ;).
How much flex there is in the system depends on the reel design. I would also go with the bucket of bricks test approach on this and not material deformation calculations :D
-J
Quote from: mhc on June 08, 2015, 12:49:58 AM
Interesting comments on the sync V async dogs issue. With the long curved skinny dog that bent during the test, a second dog close to being in sync might have saved it - which is what you said. The first to take the load needs to flex or deform before the second takes some of the load. The amount of flex or deformation needed would depend on how close the dogs are to being perfectly synchronized.
The link & spreadsheets work fine - thanks. Should the force on the dogs calculated in the third sheet be the torque divided by the radius ie; decreasing as the radius increases for a given torque?
Oops! Thanks!!! - more proof that my my math is not to be trusted. Updated the post with the corrected spreadsheet (version 2 in title).
You are correct. That is why a bigger ratchet is better (and more common on newer reels)- you can fit more smaller teeth on it (less backplay) and still have a stronger anti-reverse.
Dave, being in construction for over 40 years and building things by hand, I tend to lean towards actual tests instead of formulas, sorry, its just the way I am, so be patient with me ;D, I do enjoy all that you've been showing us.
On the dogs, giving the right amount of force and causing some flex with the dogs or ratchet, do you believe the two dogs would share the load? I believe there would definitely be some flexing and I also believe at some point the load would be shared.
When that does happen, I couldn't tell you, I'm not that smart, but I do believe it would also be related to the material used and not just the amount of force applied.
Your statement makes sense to me, about never being able to having true synchronized dogs, but under the right conditions while using the tool, it could be.
Not related and pulling away from this, do you believe double dogs is a better choice than just one dog in fishing reels? and the you also agree that trying to get them synchronized is a better choice than alternating?
Sal
Quote from: Alto Mare on June 08, 2015, 10:33:41 AM
Dave, being in construction for over 40 years and building things by hand, I tend to lean towards actual tests instead of formulas, sorry, its just the way I am, so be patient with me ;D, I do enjoy all that you've been showing us.
On the dogs, giving the right amount of force and causing some flex with the dogs or ratchet, do you believe the two dogs would share the load? I believe there would definitely be some flexing and I also believe at some point the load would be shared.
When that does happen, I couldn't tell you, I'm not that smart, but I do believe it would also be related to the material used and not just the amount of force applied.
Your statement makes sense to me, about never being able to having true synchronized dogs, but under the right conditions while using the tool, it could be.
Not related and pulling away from this, do you believe double dogs is a better choice than just one dog in fishing reels? and the you also agree that trying to get them synchronized is a better choice than alternating?
Sal
Hi Sal
First, you are being way too modest. Second, Somehow folks have me confused with a mechanical engineer. I just play one on the Internet ;)
The engineering part of this does not replace the testing. The best result is when everything is combined in the right amounts, which is what I hope we are doing here. But whoever is doing the work gets to pick the methods.
Some imes you need to rely more on engineering and science - it wouldn't be advisable to use trial and error to build railroad bridges.
Sometimes you need more live testing: I have been working on a swimbait for over two years now. There was no chance that I had the brainpower to figure any of this out with hydrodynamics :). So this problem was pretty much solved with trial and error, and very little engineering.
Regarding materials- Agree that the materials will affect the outcome. Different flex, stiffness, impact resistance, etc. If we made the dogs out of rubber, we would get very good load sharing, but also busted knuckles :). Another example- Replacing plastic sideplates with aluminum might change which part of the system flexes or fails.
Regarding asynchronous vs sync double dogs vs single dogs.
1. if you gave me a modded jigmaster:
for big yellowtail in the kelp beds - the further I can button down the drag the better. My chances are better with sync.
for pulling big snappers out of mangroves- this is short line- u-turn bites. Async saves me a couple inches on the u-turn.
Fishing enjoyment- I marginally prefer less back play ( not enough to go to one way bearings) but this is a personal preference.
2. Designing a reel from scratch for me - I would use a large ratchet with async dogs. The engineering shows that it should be possible to properly design dog systems that can handle the load beyond what the gears can take. Having a redundant dog seems unnecessary. If you make the ratchet big enough, you can probably get away with a single dog with minimal back play in a well designed system.
3. Designing a reel to be popular - One way bearing unless the load is too large.
Correct me if I am wrong, but I think your goal for multi-dog is primarily increasing the strength of these classic reels. Decreasing backplay is less important. Exactly how much flex or failure occurs before load sharing kicks in will affect the ultimate strength, but I believe that sync dogs will probably have the best chance to meet your goals irregardless. But you already knew this:).
Jurelometer does trial and error on swimbait design (this is not even half of them-eek)
(https://lh3.googleusercontent.com/-Bk3te0DZRLU/VEAYWgGDUBI/AAAAAAAAA7c/jne3cZem_64/s640/image.jpg)
12 months later, I finally got around to testing another set of dogs - this time with a gear in place as Sal had suggested.
I had added an extra 2 dogs and a Cortez Conversions 98-155 9 tooth sleeve to a jigmaster bridge and was concerned the smaller diameter of the ratchet would put extra load on the dogs and the smaller teeth would apply that load to smaller area at the tip of the dog. (I used the 155 sleeve because the smaller ratchet gave enough room to add the dogs)
The bridge;
(http://i1243.photobucket.com/albums/gg549/mhc14/AT%20forum/DSCF2775_zps6qtxwkup.jpg) (http://s1243.photobucket.com/user/mhc14/media/AT%20forum/DSCF2775_zps6qtxwkup.jpg.html)
Using Dave's spreadsheets and assuming a spool diameter of 1.8", drag of 30 lb and gear ratio of 4:1, I got a torque of 108 lb/in.
Instead of the crescent wrench used last time, I screwed an old handle to a flat piece of iron bar with a hole to attach the spring scales 10" from the centre of the sleeve;
(http://i1243.photobucket.com/albums/gg549/mhc14/AT%20forum/DSCF2783_zps9kqnwnup.jpg) (http://s1243.photobucket.com/user/mhc14/media/AT%20forum/DSCF2783_zps9kqnwnup.jpg.html)
With a 10" lever, the force required at the spring scale is 10.8 lb (108/10). I started at 13 lb equivalent (~4.7 lb on the scale) and checked the dogs, posts and sleeve. There was a slight dimple on the face of the second dog where the point of the tooth contacts. I then applied 20 lb drag equivalent (~7.2 lb on the scale) and checked it all again and couldn't see any change.
Finally I took it up to around 30 lb drag equivalent (10.8 lb on the scale). This time the faces of the 2nd and 3rd dogs were noticeably indented by the ratchet teeth the original dog slightly marked. They still worked fine and I'm sure if they had been shaped to match the angle of the teeth there would have been marked less. The posts stood up to the load - I couldn't see any deformation and Tom's ratchet was unmarked as I expected.
After 13 lb equiv' showing slight mark in the tip of dog 2;
(http://i1243.photobucket.com/albums/gg549/mhc14/AT%20forum/DSCF2777_zpsicksqnaq.jpg) (http://s1243.photobucket.com/user/mhc14/media/AT%20forum/DSCF2777_zpsicksqnaq.jpg.html)
After 30 lb eqiv' showing more obvious marks in dogs 2 & 3;
(http://i1243.photobucket.com/albums/gg549/mhc14/AT%20forum/DSCF2782_zps2okz9b2v.jpg) (http://s1243.photobucket.com/user/mhc14/media/AT%20forum/DSCF2782_zps2okz9b2v.jpg.html)
The dogs;
(http://i1243.photobucket.com/albums/gg549/mhc14/AT%20forum/DSCF2791_zps0ipacos5.jpg) (http://s1243.photobucket.com/user/mhc14/media/AT%20forum/DSCF2791_zps0ipacos5.jpg.html)
The posts and sleeve;
(http://i1243.photobucket.com/albums/gg549/mhc14/AT%20forum/DSCF2788_zpsdomm8pya.jpg) (http://s1243.photobucket.com/user/mhc14/media/AT%20forum/DSCF2788_zpsdomm8pya.jpg.html)
Recalculating this test and changing the gear ratio to 4.8:1 the calculated drag equivalent is around 25 lbs - which is more than enough for 50 lb line.
This test has given me confidence Tom's 98-155 sleeve will work in a jigmaster with three alternating dogs and DIY dog posts. Thanks again Dave for coming up with the concept.
Mike
Great job Mike, I always enjoy homemade gadgets.
Now, are you saying that you've calculated the distance on that steel bar from the handle?
(http://i1101.photobucket.com/albums/g431/pescatore1/pescatore1021/DSCF2783_zps9kqnwnup%20.....jpg) (http://s1101.photobucket.com/user/pescatore1/media/pescatore1021/DSCF2783_zps9kqnwnup%20.....jpg.html)
If I had to figure that one out on a calculator, it would make my head spin.
I could get it done though, but it would require lots of manual labor, as drilling holes every 1" or so, set a bolt in the center and a heavy spring on the right, with a witness mark.
Thanks for all your hard work Mike, it's very much appreciated.
Sal
Thanks Sal. The 10" measurement is from the centre of the gear sleeve to where the scale is attached, the steel bar and handle are rigid - there is a screw from the underside where the handle nut lock screw goes;
(http://i1243.photobucket.com/albums/gg549/mhc14/AT%20forum/Sals%20edit%20torque%20bar%202_zpsdbl3srgy.jpg) (http://s1243.photobucket.com/user/mhc14/media/AT%20forum/Sals%20edit%20torque%20bar%202_zpsdbl3srgy.jpg.html)
I thought of multiple hole locations but it's easier to calculate the torque with a 10" lever.
Mike
PS, I hadn't noticed that 'alantani.com' logo on my wrench before - must be the camera angle. :D
haha...I softly placed that in to see if you would notice, tried to go lighter but couldn't ;D.
Thanks again Mike, great job on the dog posts as well...good stuff!
Thanks folks. But I can't see the photo f bucket pictures ..?? ???
Too much unneeded information. Its just a fishing reel...
Pretty interesting read.
Wouldn't it be great if those manufacturers of quality tackle, with the resources, would engineer reels at certain load bearing capacities without having to "overbuild" systems(too much weight & cost---but who does that these days?)or cheapen parts to save money( pressure bearing metal parts, to composite plastics).
Probably too much to expect, but shouldn't, for example, a pinion bearing on a lever drag reel last at least almost as long as the the rest of the reel?