Midknot Rig

[DaFrogman]

I decided to move this from the "Midknot Strength" Thread over to this one.

Right, here is the rig guys.... Please don't laugh too much, 'cos its really simple and not as flashy as the bobbiny thingy you can whirl around...

Component wise....
1 piece of 1x2.5ft flat wood (in this case some Ikea pine shelving bits)
3x SS Steel Right Angle Shelving Supports
8x Tie wraps
12x Self Tapping Wood Screws (0.5")
3x Woodworking Fast Clamps

Basically the key to it all are the Woodworking clamps. They are very easy to use, tighten by squeezing the lever and loosen by pressing the little orange button. The clamps come with nice plastirubber covers on their jaws so that clamping mono and braid does not cause any damage even when clamped tightly.

The two furthest apart clamps hold the mono for the main part of the knot tying and the third clamp offset in the middle holds the braid at a perpendicular angle to the mono like in these pics...

Pics continue below...

[DaFrogman]

The next series of pics shows the stages of a midknot being tied with the rig. The fact that I could take the pic myself in the middle of the knot without growing an extra set of hands and without breaking the guiness book of world records for contortions speaks volumes for how easy it is to tie a knot with this rig.

This series of pics starts with;

1. the first set of wraps, 30 in all,
2. then the second set of wraps going back down the 1st set,
3. then the 1st set of alternating half hitches over the braid and mono

Saimee

[DaFrogman]

The next set of pics are the finishing parts of the knot.

1. After the 1st set of half hitches, I remove the lines from the rig to do the "pull till shoulder joints go click" procedure to tighten the wraps prior to cutting the mono tag and melting the end.
2. I then put the knot back in the rig, but this time clamp the mono mainline on one clamp and the braid on the other clamp.
3. I then start the alternating half hitches over the braid probably 10-15 of them and then finish with a blood knot type of knot using a big carpet needle or a piece of brass tubing, trim the braid tag end and melt it off neatly too.
4. I then remove the knot and do the pulling test again to see if anything pops aside from my wrist bones

A bonus advantage I have found with this rig is that you the base clamps flex slightly and maintain a nice tension on all the lines which assists me greatly in keeping the knot tight and even.

[DaFrogman]

A final set of pics of the rig. The rig is very portable and usually lives on the top shelf of one of my shelving units in the workshop.

I have included a pic of the modified right angle shelf supports that I use to secure the clamps to the wood. I went a bit further by bending one end of the supports right in the middle of a screw hole and then cutting it off and a bit of minor grinding and shaping with my Dremel. I did this to make sure that the clamp shaft was securely held both laterally as well as vertically.

Also included is a pic of the gloves I use to tighten the braid and also the grooves left in my hands after tightening the knot, even with the gloves on..

I reckon that there are tons of ways of building rigs like this one... I just used what ever I had lying around my little workshop. I am sure you guys will figure out better ways of building it.

I would welcome any suggestions to improve it.

Regards,

Saimee

[Makaira]

Dude .... I really take my hat off to the extent you guys go to for tying a knot ....... true devotees & passionate about your hobby!



I am not worthy!!!!! I use the uniknot for practically everything.

[DaFrogman]

Ahhh KK,

When I get a bit stressed out , I've found that tying a new confusing knot or something like the midknot keeps my mind off whatever is pissing me off...

So there is a somewhat dubious thereaputic side to the insan ...oopps I mean obsessi ....oops I mean passion for the sport... That plus a mysterious addiction to using power tools means that I tend to build all kinds of stuff from the junk lying around the workshop...

Coming maybe next week, a simple rig to turn down the outer diameter of Carbontex washers....

Saimee

[tmlim]

Saimee,

Thanks for sharing the design of your rig. I appreciate it certainly requires some brain storming sessions to develop this thing. It surely makes light work on the weaving in and out of braid, while tying the half-hitch knots. These knots sometime cause me to start tying all over again on a rocking boat.

I am also impressed that the SS Steel Right Angle Supports can withstand the pulling and compression forces applied on the knots. To provide a clearer picture on the procedures taken, I suggest that you label the steps besides the pics.

Although wise man thinks alike, I would like to share with you my conceptual design of the mid-knot’s rig drawn a year back. It is composed of a SS fork to hold the braid, and then the mono line is secured onto two small diameter pipes at both ends. The handcuff-knots of the braid are created by oscillating the fork (similar to BBQ chicken wing action) in the CW and CCW directions, i.e. below and above the mono line as shown in the second pic.

While your rig is already a tested one, I am still too busy to complete fabrication of this mid-knot tying rig … still dreaming of creating something small, so that I can bring it onto the boat. I also have to agree with you that the bobbin rig someone posted is indeed a clever design.

[physlo]

Tie here, tie there, turn here, turn there geez....so chim lah but thanks for sharing guys.

[DaFrogman]

Tm,

Dude, I never even got round to sketching out my rig.. As for the pics, they don't have labels or titles as I didn't intend to make them into a midknot tying tutorial but I might work on that later.

I kinda sat down one night to tie a midknot and got fedup trying to rig a pair of light bench vices to secure the mono without damaging it.... Then looking around the ole worktable, I spied a bunch of those wood working clamps that I had picked up out of curiosity a month before... .... one thing led to another and a bit of work later I had the rig. The stainless steel supports actually do not support a lot of tension, just enough to keep the mono tight and to prevent it from twisting under the torque of the braid wraps that are also under tension.

Looking at your diagram, I can certainly see the utility and portability in the fork system. But I wonder how you secure the mono leader. If you were to use a hollow shaft running through the bearings, I guess that would be ideal since the mono could then run through the shaft and if you threaded the shaft (no idea on the thread pitch) and the shaft receiver body, then the shaft and fork could naturally move up the mono, laying the braid as it goes along. How to get it to rotate back is another matter as is how to secure the braid in the tips of the fork so that it can feed under tension....

Hmmmmm.... sounds like fun dude. Hey its the getting there thats the fun bit.... the bonus is watching it actually work. The main thing about the bobbin that I did not like was that you had less control of the braid during the wrapping process. I prefer to wrap the braid by hand using "feel" tension and controlling the spacing of each wrap and especially the spacing of the middle set of wraps which have to leave a bit of space between them.

I have thought up a portable version of my rig, using machined stainless steel feet that you just slot the clamps into and a skeletonised scissor frame (possibly made of aluminium) that would be much smaller, lighter and easier to store.... but thats for another day when I get bored or see something in a hardware store/machineshop/workshop that would help me build the portabe rig.

Thanks for sharing your thoughts and cool ideas dude. Next time I'm in town I must drop by to see you.

Saimee

[sunburned]

Hi Saimee,

Thanks for this excellent writeup on the Midknot rig. Probably the best that I've seen after doing some searches on the web (and in a language that I can understand, haha). Give me more ideas on tying shock leaders.

Cheers,
Sunburned

[tmlim]

Originally Posted by DaFrogman

Looking at your diagram, I can certainly see the utility and portability in the fork system. But I wonder how you secure the mono leader. If you were to use a hollow shaft running through the bearings, I guess that would be ideal since the mono could then run through the shaft and if you threaded the shaft (no idea on the thread pitch) and the shaft receiver body, then the shaft and fork could naturally move up the mono, laying the braid as it goes along.

You are one tough customer to handle, dude. To be honest, I have not thought deeply into securing the other end of the mono which I normally do with my teeth. By raising this question, thankfully you have given me some lights to the problem. Yep, running the mono through the bore of the handle would be ideal to avoid collision with the fork; at the expense of a bigger handle design. At the moment I have no intention to thread the handle, however, it is designed to rotate, slide and pivot the fork … perhaps the attached picture can tell a thousand words here.

Originally Posted by DaFrogman

How to get it to rotate back is another matter

Hmmm … good question, this is best done on a CAD’s solid modeling to examine possible collision between handle/fork and mono. Hence, the best dimensions of the device can be determined prior to fabrication.

Originally Posted by DaFrogman

as is how to secure the braid in the tips of the fork so that it can feed under tension....

Another sharp question, the braid will sit in the recesses of two pins at the front of the fork. The tension on the braid can be realized by implementing a fork that resembles the one we all use to hang galas/clothes. Further continual tension on the braid is attributable to the two C-shaped compression springs placed besides the pivoting fork’s arms. In addition, two spring-loaded washers (similar to the one used by rod builder to control thread tension) compressing the braid are implemented to ensure constant tension.

Originally Posted by DaFrogman

The main thing about the bobbin that I did not like was that you had less control of the braid during the wrapping process. I prefer to wrap the braid by hand using "feel" tension and controlling the spacing of each wrap and especially the spacing of the middle set of wraps which have to leave a bit of space between them.

Agreed, but this idea is simply out-of-the-box. Incidentally consistent with your observation, the other benefit of this device is that the sliding fork mechanism allows the tension on both sides of the wraps to be balanced by stretching and compressed the braid, that is, by sliding the handle bar in the horizontal direction.

Lastly, Singapore and her fishos, surely welcome Brunei’s favorite son here anytime. Will PM you my contact, but I have trips on early May and mid-June.

Cheers
TM