How does one measure the CCS numbers of a rod built with the XO Skeleton seat/grip?

In a build with a conventional seat/grip set, where the blank goes to the end of the grip, the CCS measured before and after the build are virtually the same.

Take for example a NFC MB724-1. According to my measurements, the CCS numbers are 71 degrees and 583 grams.

If I build this rod with the XO Skeleton seat/grip, how do I measure the final build CCS? Do you put the handle in your support device at the rear end of the grip? If you do, that is going to change the length from 7' to ~8'+/- and CCS numbers of the final build. How would you estimate the CCS of this final build without having the XO skeleton seat/grip in hand?

If you have the XO Skeleton seat/grip in hand, how would you secure the blank in the seat/grip to do the measurement without gluing it? I think without gluing it, the attachment would not be secure enough to prevent small movements and skew the numbers.

I want to know the final CCS number. That is a high priority target in any build.

If you change the rod by adding a handle that extends the rod then just treat it as a single unit. The butt of the handle now becomes the butt of the rod. Shim it with tape or whatever and take the measurements as you would normally do. You can changed the length so the numbers will also change. REmember the deflection distance will also change because the overall rod is now longer.

You can also do a double dowel rig with the front dowel under the rod and the rear one over it. Tape it to hold it from slipping. When the load is applied it will be stable. The dowels should be placed at 10 % of the length of the rod. If the dowels are sunk into a piece of plywood, it can be placed in a vice's jaws to hold the rig, then leveled as necessary. Measure from the tip to the floor, don't need the big sheet of particle board. This rig has advantages and disadvantages, but might be something you might use.

Mike,
I understand your answer. I use a backlash device for my measurements and am pretty anal about the details, use a level, measurements down to the mm, and weights down to the gram. I'm just trying to get a feel for how the numbers will change.

If someone is building a rod with the XO Skeleton, can you post the before and after CCS numbers for comparison?

The numbers should not change, in my opinion.

I have a spinning rod that I built using the XO skeleton grip. I took CCS numbers for the bare blank, and sometime today, I'll take CCS numbers for the completed rod. I'm also into the process of building a casting rod using an XO skeleton grip. As with the spinning rod, I took CCS numbers for the bare blank, and I'll take numbers for it at the same time I take them for completed spinning rod.

Here is the thing about the XO skeleton grips. How powerful the blank is, and how you need to, or how you decide to use the blank, is going to have a bearing on the CCS numbers you get.

Let's say you're using a light powered blank that bends deeply into the butt of the blank, and you pass the blank completely through the XO skeleton grip, the grip stiffens the butt of the rod. The rigidity of the grip is going to not allow the blank to bend as deeply into the blank's butt. Power numbers should increase, and AA should increase.

If you need to trim length off the butt of the blank you're using in order to be able to insert the blank into the grip, how much the CCS numbers would change from those taken on the bare blank is going to depend on how much you had to take off the blank. and how far you inserted the blank into the grip. As for the MB 724 blank mentioned in the opening post .......... I have an MB 724 X ray blank here at the house, and it will not fit into the end of an XO skeleton casting grip. I believe if memory serves me correctly, the casting and spinning version of the XO skeleton grip have the same ID at their respective thread barrels. I do know that both of them can use a size 16 reel seat hood from Pac Bay, Forecast, and Fuji reel seats.

Anyhow ...... how much you take off the butt and if you're using the grip to increase the length of the blank, is going to affect CCS calculations, and numbers.

As I said, I'll take some numbers later today. Once I do I'll be sure to post them here.

Thanks David. Please also include how much of the blank you inserted into the XO Skeleton.

Ed

Ok, I just got done checking the CCS numbers for the spinning rod I built using an XO skeleton grip. And a casting rod I'm building using an XO skeleton grip.

For the spinning rod I used an MB 733 X ray blank. I had to trim length from the butt of the blank to get it to fit into the thread barrel on the XO skeleton grip. I took 7.375" off the end of the blank, and have 7" of the blank stuck inside the XO skeleton grip. Total length of the finished rod from the end of the tip top to the end of the butt cap is 86.625". CCS numbers for the bare blank in its' stock form. IP 557 grams, AA 76.4. CCS numbers for the completed rod. IP 571 grams, AA 76.4. A very slight change in IP, and no change in AA.

The same cannot be said about the casting rod I'm building using an XO skeleton grip, and an MB 725 C6O2 blank. MAJOR difference in CCS numbers. I was so shocked by the difference that I pulled the blank out of the grip and tested the bare blank again to make sure I didn't make a mistake when I checked it when I first got it. I had a 5 gram difference from the very first CCS numbers I took for it. I put the blank back in the grip and tested the rod again. Same numbers I came up with the first time I checked it.

Numbers for the bare MB 725 C6O2 blank. IP 712 grams, AA 75.3. CCS numbers for the blank inserted in the grip as it will be when the rod is finished. IP 796 grams. AA 77.8.

Needless to say I was shocked at that big of a difference in IP. That's why I checked it again. When I checked the bare blank this time, I looked at how much flex there was in the butt of the blank, and I was surprised to see how much flex there actually was for a blank of that power. The flex was completely to the forward blank support of my CCS jig. For the particular blank that means the forward support had 8.625" of blank behind the supports forward edge. There is 13.875" of the blank inside the XO skeleton grip. As there is absolutely zero flex in the grip, that means that 5.25" of the blank length that would flex using a normal reel seat / grip combination, is not able to flex inside the XO skeleton grip.

That blank flex contributes to vertical tip drop. Without that flex you have to load the blank more to get the tip to travel the same vertical distance.

I mentioned in my previous thread that the grip would affect the CCS numbers on light power blanks that bend deep into the butt of the blank. Seems it's not just the light powered blanks that have that much flex into them. So why weren't the numbers so vastly different with the rod build on the MB 733 X ray blank. It's a less powerful blank than the MB 725 C6O2 blank. I can only postulate as to why, but here is what I would bet on the reason to be. Blank diameter and blank taper.

At the very butt of the blank, the MB 733 blank had a diameter of .611". The diameter of the blank where it exits the XO skeleton grip is .518". The diameter at the very butt of the MB 725 blanks has a diameter of .473" The diameter of the blank where it exits the XO skeleton grip is .489" Yes, it gets larger as it goes up the blank, and you can actually see it with the naked eye. I thought it was odd when I first looked at the blank, but since it passed completely through the grip, I wasn't asking any questions. lol If I remember correctly there was talk about NFC making a length of the butt of the blanks more uniform to make installing reel seats and grips easier. Pretty sure I read that in a thread somewhere.

Anyhow..... the MB 733 blank having a larger diameter doesn't flex as deeply into the butt as the MB 725. The latter isn't a guess of mine. I have a MB 733 blank that I haven't built on yet, so I took it down and put it in my CCS jig and loaded it with 552 grams, which is the CCS number I got for it when I measured it right after receiving it. It doesn't flex nearly as much that deep into the blank as the MB 725 does. As the butt section of the MB 733 doesn't flex as much, it makes sense that the grip not letting it flex, isn't going to have that drastic of an affect.

I still can't believe the IP numbers are so much different for the MB 725 blank. But you can really see the blank flexing as I said, all the way back to the forward blank support of my CCS jig. In case anyone is wondering what my CCS jig looks like, here is a picture I took of it when I first built it. I did one modification to it since building it. I added a center dowel that I slid a light wire spring over so it would help hold up the support while adjusting the height of the forward rod support.

[www.rodbuilding.org]



Edited 2 time(s). Last edit at 03/02/2024 02:58PM by David Baylor.

David,
Thank you for the info. I was hoping you would provide it since you spent so much effort in detailing the other aspects of the XO.

For the MB733, It started as an 87" long blank. After the build, it was 86.25". So, it looks like you essentially replaced the bottom 14"+/- of the blank with the XO grip. I would propose that this is why the numbers hardly changed. The stiffest part of the blank was replaced with a stiff handle.

For the MB725, It started as an 86" long blank and after the build was, I'm guessing about the same. This time, you replaced a more flexible butt end with a stiff XO. I propose that is the difference in the numbers. It made the blank more powerful and faster.

Since you haven't built the MB725, would you please take the measurements with the blank inserted into the XO as designed by NFC. I.e. the first 3-5" only inserted into the XO. I'm very curious.

Ed

Ed, since you're aware of how I've detailed aspects of the XO skeleton grips, I hope you understand when I say, sorry but I won't do as you ask, and just insert 3 - 5" of blank into the grip to test it. I wouldn't trust it.

The casting version is no different than the spinning version in respect to how much of the blank is actually fully support by the ID of the grip. If you're not passing the blank completely through the grip, then it's only 1.75". The casting grip thread barrel may measure 1.875" long, as it doesn't open up as quickly, or to the degree that the spinning version does. I just can't trust that small amount of an blank / grip interface. Also, I trimmed length off of my thread barrel. It now only measure 1.25" Even a smaller amount of the blank would be fully supported.

If you have the blank you want to use an XO skeleton grip in hand, you can do CCS on that blank using how much of the blank you're going to insert into the grip as your forward rod support distance. If you're only going to stick 3" of the blank inside the grip, then just support 3" of the butt of the blank. To determine how much blank deflection you need to achieve just add how much length the rest of the grip will add and take 1/3 of that length as your deflection distance. It wouldn't be hard to do. But, if you are talking about the MB 724 blank you mentioned earlier, if it's butt diameter is the same as the blank I have here, mine has a butt diameter of .601, then you'll have to trim length off the butt in order for it to fit in the XO skeleton grip. According to the dimensions on the NFC web site, you'll need a butt diameter of .579 or smaller to get it to slip into the thread barrel.

Anyhow ..... sorry I can't help you out with the testing you asked about.



Edited 1 time(s). Last edit at 03/02/2024 07:05PM by David Baylor.

David,

Thanks for the response. I understand your concerns. You did offer some suggestions on how to estimate the final numbers when using the XO that got me thinking about how to do it with my CCS setup.

Ed