Problems with Leon Paul GT points

[FenceForFun]

(I wanted to add this to an old "The Best Foil Point" thread Joe Biebel started, but it wouldn't let me)

Overall, I like the LP GT points when they work, but they are not without problems.

In my experience of using them for about 6 months, it seems the 5mm slots, necessary for tightening the barrel unless you have a specialized tool (which apparently LP uses, but doesn't sell), weaken the barrel and makes it prone to cracking.

So far I cracked 4 barrels while rewiring. These were already used barrels. Externally, they seemed in good shape. In my judgment, I didn't use excess force. The problem seems to be that these barrels tend to expand at the base upon the first installation (and maybe in use). When reinstalling, I first tighten with my fingers and then use the LP 5mm spanner. In all four cases, I hadn’t even make a half-turn with the spanner - and it was turning very easily - before the barrel cracked, close to where one of the slots are machined.

It's possible that the blades themselves are a contributing factor; if they are a bit too thik below the thread. But I am using Vnity blades, which is one of the brands LP sells, so presumably LP staff would have reported problems with Vnity blade + GT barrel combination.

The reason I had to rewire is another LP problem - the wire. Joe Biebel mentioned the wire pulling out of the contact when wiring. I experienced that too. But apparently it can also happen in use. In two of my weapons, after they started to give me off-target lights, I found little pieces of wire inside the barrel, indicating that perhaps the crimping was overdone and weakened or broke the wire inside the contact. Eventually the bottom part of the wire pulled out and the little top piece - about the size of the brass contact nipple, ended up in the barrel. In another weapon, the wire just pulled out of the contact completely when the blade was really bent in a lunge. That would be the case of under-crimping. The reliance of crimping seems to be a design weakness that leads to manufacturing problem, as it is easy to over-crimp and break the wire inside, or under-crimp.

The brass contact base is not glued to the plastic cup. It has little teeth presumably to keep it in place by friction, but they don't do that 100%. That might be a contributing factor to the wire breaking out of the contact: the tip turns in action, which in turn turns the spring which puts a turning force on the brass contact, potentially twisting the wire inside.

I decided to start attaching contacts to the wire myself, with a couple modifications:
1. Glueing the brass contact into the plastic cup.
2. Putting a bit of low-voltage conductive glue on the wire before inserting into the contact and crimping (with round nose pliers to minimize the chances of weakening the wire inside).
3. Leaving a longer piece of wire to stick out of the contact, and then bending it down along the nipple, then back up and wrapping it around the contact nipple and itself. This definitely prevents the wire from pulling out when re-wiring, but I haven't used the two weapons I wired this way long enough yet (about 4 club nights so far and one competition) to report how it all holds up in long term use.

I also have to report that the sleeves still separate, despite the LP post that the problem was solved months ago. (BTW, what is lactate [glue] Barry Paul suggests can be used to re-attach?) Unless LP is sending me tips manufactured before the fix. Which is not out of the realm of possibilities, as I recently ordered GT barrels and received regular ones (I can tell by the color) instead. (LP Quality Control disappoints at time too: I received G-Pro wired blade with the wire glued visibly above the grove. But the Customer Service is responsive: they made up for it.)

So still some problems to solve in the quest for a perfect foil point and a perfect equipment manufacturer :-).

[forethought]

Originally Posted by FenceForFun

(BTW, what is lactate [glue] Barry Paul suggests can be used to re-attach?)

I believe what he's referring to is LocTite, more specifically the blue colored thread locker. Loctite is a brand that includes many adhesives and lubricants, but the more common product amongst fencing armorers are their thread lockers; you apply to the threads and once the liquid cures it adheres the two pieces together somewhat so that, typically, the barrel does not work itself loose quite as easily.

The Loctite thread lockers come in two common "flavors", blue and red. Most people use the blue kind, which, as advertised, requires merely some form of mechanical leverage when trying to undo two things that have been adhered using the thread locker; the red kind, however, is a bit stronger, and instructions for loosening two things joined with this include the application of direct heat first.

Hope that helps clear that up.

[larkmaj]

Originally Posted by forethought

I believe what he's referring to is LocTite, more specifically the blue colored thread locker. Loctite is a brand that includes many adhesives and lubricants, but the more common product amongst fencing armorers are their thread lockers; you apply to the threads and once the liquid cures it adheres the two pieces together somewhat so that, typically, the barrel does not work itself loose quite as easily.

The Loctite thread lockers come in two common "flavors", blue and red. Most people use the blue kind, which, as advertised, requires merely some form of mechanical leverage when trying to undo two things that have been adhered using the thread locker; the red kind, however, is a bit stronger, and instructions for loosening two things joined with this include the application of direct heat first.

Hope that helps clear that up.

I think FFF is referring to the problem with LP GT tips were the metal sleeve becomes seperated from the rest of the point and slides up and down, this makes the tip not function. Both of the LP tips I use in my foils have developed this problem. I just use a dab of superglue then vicegrip the collar to the top of the tip. The only other problem I've had with the LP points is the wire tends to strip more easily than other wires. At least in my experience. I love the classic italian point design and the epee screws.

[forethought]

Oh, wow. I haven't heard of that problem, and of the four weapons I have wired with LP GT points, thankfully I haven't experienced this.

My bad, I thought he was still talking about the barrel problem, I guess that's what I get for skimming.

[Jvanhousen]

Originally Posted by forethought

... the red kind, however, is a bit stronger, and instructions for loosening two things joined with this include the application of direct heat first.

Luckily the area of contact that fencers worry about (tip threads) is so small that heat is not required to overcome its (RED Loctite) gluing strength.

[Blakeian]

I haven't experienced any of those problems and I've been using GT Pro tips since they phased out the older, stubbier, version. At most I tend to have a mystery white light problem which is fixed by cleaning the barrel or just unscrewing and rescrewing the screws. Blade wise I use BFs and Flickmasters but as soon as my last flickmaster breaks I'll be using BFs exclusively until I see something better.

That said I'm about to trial the FWF Next Gen point and see how it compares.

[Alex_Paul]

Thanks for your posts

Feedback is something we thrive on.

We put barrels on using a modified drill chuck rather than a spanner.

I have seen a lot of blades where after the thread they suddenly get wider at the tip. This is probably causing the splitting. If you check out the rules you will see that there is a requirement for a counter bore on the points m12.1.6. To my knowledge no other manufacturer does this making all of their points illegal! not that anyone notices or cares of course...

This counter bore means that if the tip of the blade isn't finished properly to 3.5 mm then as you tighten the GT point down the non threaded part of the blade pushes out on the counter bored part of the point and splits the point. The two solutions are to grind the blade down to 3.5 mm or grind the counter bore off the point.

You shouldn't have to do this but I think it is a blade problem rather than a point problem.

Re wires, in response to feedback here we are looking at re designing them with solder instead of a crimp. The pre stretch that is common in the USA is not in the UK so there has never been a problem with friction or interference fits on the wires here before...

Re tips seperating, this shouldn't really happen but it doesn't affect the function of the point as either inner or outer surface can act as the bearing surface.

Thanks again for the feedback.

[forethought]

Originally Posted by Alex_Paul

We put barrels on using a modified drill chuck rather than a spanner.

Alex, just something that I've come across, in that when I tried using a spanner on your GT barrels, the barrel is just ever so slightly larger than 5mm at the two spanner points. I tried two different 5mm wrenches, one of which I ordered directly from you, but neither wrench would fit over any of the six GT barrels I tried (though they did work on the German barrels I had on hand). In the end I filed down the opening of one of the wrenches in order to have it fit your barrels, but I was wondering if this was a manufacturing oversight, or do you intentionally have the spanner points on your barrels slightly wider than 5mm?

BTW, it's between 5 and 6mm on all my barrels, because I have a 6mm wrench as well, and it was too big.

[Alex_Paul]

Just verified this with calipers! OOPS... It shall be sorted ASAP.

Sorry,

Alex

[larkmaj]

Originally Posted by forethought

Alex, just something that I've come across, in that when I tried using a spanner on your GT barrels, the barrel is just ever so slightly larger than 5mm at the two spanner points. I tried two different 5mm wrenches, one of which I ordered directly from you, but neither wrench would fit over any of the six GT barrels I tried (though they did work on the German barrels I had on hand). In the end I filed down the opening of one of the wrenches in order to have it fit your barrels, but I was wondering if this was a manufacturing oversight, or do you intentionally have the spanner points on your barrels slightly wider than 5mm?

BTW, it's between 5 and 6mm on all my barrels, because I have a 6mm wrench as well, and it was too big.

I can usually get a 5mm spanner to fit by sliding it up from under the barrel as opposed to sliding it in from the side. The major problem is that the flats are not large enough so the spanner will often lose its grip and rotate around the barrel.

[HDG]

I find that a small adjustable wrench does the job quite nicely.