acrylic

Hi Smitty,

Why does it have to be aqueous? Nylon is hydrophobic - water does not "wet out" on Nylon (and many other polymers as well). Unless it is solvent-based, the solution will have a hard time penetrating the spaces between the fibers of the twine knot which, as you have stated, needs to be rock-hard.

If you can do it, I recommend solvent-based. The lower the viscosity of the component mix, the better.

Mike

This is interesting. I'm tempted to experiment with this myself. Try different amounts of liquid detergent in water and mix it with water based varnish to see how it works with respect to how well it soaks into nylon cord and how hard it dries. I can only guess at the outcome.

Ed Weldon

What type of water based varnish would be best. I have tried the type used on wood flooring and it hardened but not nearly to the degree I had witnessed. However, i used it full strength and with out any detergent.

I have seen a solution 15 years ago that was water based and thicker than just plain water.

When mixed 50% with water it was coated on nylon knots holding netting to a rope for an outdoor base ball batting cage.

In 30 minutes the knot was so hard it could not slide at all ( even with great effort of tugging) on the rope . In fact it required some effort to cut the knot.

I only know it was called 'acrylic' by the man selling it.

I'd like to see if there was some way to try and duplicate as there is no way to find this person or his product, at least where i tried.

Mike,

The petro based solutions available do not hold up as well as this "mystery" water based stuff I saw years ago.

I realise nylon does not hold water but when this solution dried off, what it left was so hard the knots didn't budge.

the petro based coatings on the market today are sooooo expensive and the end result is that they do not seem to hold up as well as this mystery solution of years ago.

Plus, no smell, no fumes, no vapors, no fire hazzard and the mystery stuff cleaned up like latex paint....except when it was put on NYLON (PA).

Strange stuff which is why I am asking here on this forum.

Thank you.

If You dont mind, I would like to know the purpose of such undertaking. What is purpose of this knot and why You think there is need to make it stone hard?

There are many kinds of knots available, and as any fishermen can tell you there are knots specially suited for Nylon. If You want to avoid untying of knot made, then choose some fisherman knot. Such knots need no further interventions like this as they are tighter more they are used, so there would be no failure in use.

Some kinds of ropes made of knitted threads could be melted and pressed together to form connection strong as rope itself, if not stronger, and there is way to limit connected area, which is hard. I dont know whether it would be applicable in this case, but if it could be done then the knot would be smaller than before this operation, not become bigger blob that You want to avoid.

If You need to do it on many knots, then appropriate tool could be devised that would heat it on proper temperature, and maybe before melting one layer of same kind of nylon thread could be added to preclude that under pressure some strands become squeezed in half, at least on rope going in and out of knot......

If You make the tool, then it should be made of Brass to prevent gluing of Nylon to tool.

For one time job, high temperature air blower could be used carefully with simultaneous slow horizontal turning of knot under treatment and cooled with cool air or by dipping or spraying by cold water.

I hope this help.........

This twine is slightly less than 3.5mm . It holds a netting that is 4mm in dia. and it goes around a 10mm dia. Polyethylene rope to hold (base ball) netting.

There are numerous knots used but as the ball hits the panels they all work themselves just a tad bit loose and then they slide. They slide just a little but it does look ugly after a few weeks of hitting.

There are numerous petro based coatings and some water based coatings. They all harden the strands of the knot (which have a 5 wrap design). However, after a while they wear or or become bleached out due to UV or weather and the nylon loosens.

The solution I saw 15 years ago went on with a 50% mix of water and hardened the knot strands so much that the knot stayed mostly in place for years....weather, sunlight, heat, cold or UV. No staining, no vapors to speak of, no smell , no volatile fumes....nothing negative or dangerous..It washed off with soap and water until it hardened....then it was a little harder to get off your hands but eventually wore off like a latex paint would.

It DID NOT wash off the nylon twine and remained rock hard and kept the twine in a perfect , non-slip knot for years!

The petro based product has so many EPA restrictions it is extremely costly and still does not work as well as this mystery water based, not smelling solution I saw years back.

Sorry, but melting and pressing are not going to happen. Too time consuming over a 70x14x12 foot box shaped net with a knot every 4".

Thank you for any ideas .

Honored sir,

It cannot take more time than to paint it all because You would have to make several layers, but never mind that now.

With proper tool and doubling of strands you can >>weld<< end of ropes together and connection would be all but invisible. This >>weld<< is so strong that rope would break sooner than joining, I tried it! Doubling strands would also make all other knots more secure and non >>self cutting<<.........

Did You try to use Cyanoacrylate glues (we have one called CyanoFix here) or transparent Nitro Lak (KEMOCEL Nitro lak KEMOCEL nitro varnish is a primer based on cellulose nitrate, synthetic resin and organic solvents. It is rapid drying, distinguished by ... www.chromos-svjetlost.hr/en/zastita-metala/kemocel-nitro-lak/kemocel-nitro-lak.html ) that is just like nail paint just much cheaper........?

Otherwise, I would reccommend that You use >>Hangman's Knot<< as it is self tightening and cannot get loose at all, because more it is pulled, stronger it hold.

When fixing knots in nylon rope, I sometimes use a flame to melt and fuse the strands to each other. This works well for many thermoplastics.

Thank you.

I have a heat gun and German made Hot Cutting gun.

This application needs a faster process.

Thank you.

It is fast enough, just try it on some spare rope. Take each end in one pliers leaving 1/2 cm out and apply flame to both free sides. It would burn in second or two. Then just press burning ends together, wait few seconds and release pliers grip in thread.

Of course, result would be nicer if you have proper tool that can press weld with two half cylindric groowes, but You can use third pliers for this also......

It just take little practice to make it perfect......

Certainly You would lose more time chasing this what You used in past, and why it has to be so fast? Do You have production line or something?

Once You do this, it would last as long as whole net would last, so what if You spend few minutes more doing it properly?

Try looking at a product made by Varathane. It is a water based polyurethane and does turn hard as a rock. The water based material is actually harder than the solvent type. It washes out with water and is UV stable - doesn't yellow. I have put it on many floors and it works well. One caveat, It takes about 30 days to completely cure, however, it is touch dry within minutes based on air temperature and humidity. The last time I looked, a one gallon container cost somewhere around $40. Check out this site for ideas that have been done using this stuff. http://www.polyclay.com/varathane.htm

OK.

Thank you.

I'll get some at Lowes and see what happens.

Smitty

Smitty -- Please let us know how this works.

Ed Weldon

I guess I don't understand. Heating, fusing, and cooling strands of nylon isn't viable because it takes too long, but putting a chemical on it that takes 30 days to fully cure is worth a try. Is there something wrong with this picture?

Yes, that puzzles me also!

Very need for >>speed<< is also in eye of beholder, as it surely wont run away, so what is not finished one day can be continued next.......

Well, I helped best I could, but man is set on one idea quite fixedly, so what can we do... :-((

I shall unsubscribe from this thread forthwith.........

Except for the heat gun, no one is allowed within 100' of this shop with even a cigarette. No open fire at all.

Curing of wood and curing of nylon twine are two entirely different things. The process I am looking for will be dry to the touch in 30 minutes.

A petro-based product can actually set up in 30 minutes, and get rained on and then still dry. A water based product can not. In fact, just sheer humidity can keep it from curing for days .

The product I am looking for would dry in 30 minutes and be rock solid in 1 hour or less. This Varathane may just react like this when we cut it with detergent.

Drying hard and curing are two different things. Concrete can dry and be walked on, but it may be fully cured for a week.

As for burning and setting these knots. the 5 wrap Seine knot we use is self tightening . It would suffice. i just want to go that extra step to make a better product. A hangman's fishing knot would never be used to attach netting to a rope...it would slide all over as there would be only one wrap of the twine around the rope.

There will be approx. 1400 knots that need to be treated. Burning a substance over each would be very tedious and dangerous. Just the fumes would cause serious harm.

The solution I saw used a decade ago was in a bucket and the worker just held it under the rope and walked slowly, with a paint brush, dabbing the very watery coating on the knots. Within 30 minutes the knots were rock hard and the net was being rolled up on a pallet ready for shipping. He simply washed the brush as you would any latex paint.

I did try some high tech glue agent but it was way too expensive and it made too much fumes in the shop.

The knot solution I saw acomplished this feat of coating 1400 knots in about 45 minutes total time.

Thank you all and I mean no disrepect to anyone's suggestions.

Smitty