Rusted t-nuts with stainless bolts?

[kjl]

So, I went to install my FinTecs today and when I took off my old heels I noticed the t-nuts were a little rusted. The threads actually look completely shiny, but the "tops" of the t-nuts (the flat base visible if you look down through the boot after you remove the thin plastic insert) look really bad.

Was this my fault? Instead of using the black bolts that came with the old Intec heels, I was using stainless steel bolts. Was there galvanic corrosion going on? Or is this just something that happens no matter what? i.e. next time should I use the black bolts that come with the heel or can I continue to use stainless?

If the threads of the t-nuts are shiny can I continue to use them, or should I remove them somehow (looks like a huge pain) and replace them? And if I replace them, should I get new stainless steel ones, or should I use the black metal t-nuts that used to come with old intec heels? (I have a few baggies of those left over)

Thanks!

[bschurman]

Ken,

The tee nuts in the boots are actually zinc plated and I find that the only thing that will prevent that rusting is to take out your liners and dry out your boots every time you ride. Also, you can put some white lithium grease on the bolts when you put the heels on and that will prevent moisture from penetrating to the metal. Not a cure all but it will help.

If I were you, and this is just me, I would replace those tee nuts. I would just feel safer.

->Ben

[kjl]

If the t-nuts are zinc plated then that implies that the structurally important parts are probably still fine?

Hmm, I wonder if I could put a zinc washer or two on the bolt as a sacrificial anode when I put the heels on to forestall more rusting on the t-nut. Stainless runs a current, right?

[KingCrimson]

:lol: Good stuff Ken.

I'd go stainless and fuggetaboutit. Trying to cheeseball such a thing isn't a good idea, especially if you're running intecs since they are stress bearing fasteners instead of just holding the heel on for walking.

[bschurman]

I'm no materials expert so I can't say for sure about the structural integrity of the tee nuts in there. Since they are cheap, I would just replace 'em. But you'll have a hard time finding stainless ones in metric. At least McMaster didn't have them in m5 last I checked.

And if you do add the washer, make sure you put a longer bolt in there. The factory ones, as I'm sure you know since you replaced yours, are m5x20mm.

->Ben

[kjl]

My only real resistance to changing them is it looks like they may be hard to extract... maybe. I may be able to just stick a bolt halfway in there and hammer them out, but it looks like the plastic has been molded over the outer edge of the top of the tee nuts, meaning I'd need to dremel away some material first. Hard to tell.

Are you sure the factory ones are M5s? It's been years since I bought my lifetime supply of intec heel replacement bolts :D but I could have sworn they were 10-32s. In any case, if I replace the tee nut and the bolt I can get them both in my choice of standard or metric...

[bschurman]

My only real resistance to changing them is it looks like they may be hard to extract... maybe. I may be able to just stick a bolt halfway in there and hammer them out, but it looks like the plastic has been molded over the outer edge of the top of the tee nuts, meaning I'd need to Dremel away some material first. Hard to tell.

It is kind of a pain, but yes, that is exactly what you'll need to do. The Dremel is not necessary but a good hammering is. :)

Are you sure the factory ones are M5s? It's been years since I bought my lifetime supply of intec heel replacement bolts :D but I could have sworn they were 10-32s.

I am very sure that they are m5.

In any case, if I replace the tee nut and the bolt I can get them both in my choice of standard or metric...

Touche

->Ben

[csquared]

...hello rusted T nuts.

Yeah, its your fault. You probably have not been following what should be standard procedure by now. Most of us that have disassembled our boots directly after riding are aware of the very significant quantity of snow build-up between boot and shell in places that you could not even imagine snow getting to. If you just leave the liner in place, the moisture usually ends up collecting somewhere near the T nuts. As Ben said, you must remove the liners from your boots every time you ride and dry both boots and liners. I turn my boots upside down and lean them against a hot water rad after riding. The zinc plated T nuts will give long and corrosion free service this way. Also, stainless steel and steel are reasonably close on the table of nobility so there would only have been minor galvanic action in most circumstances.

I agree with Ben that you will be lucky if you can locate M5 T nuts in stainless steel. Even in Europe it might be challenging. Your best bet would be to replace them with zinc-plated but black oxide finish T-nuts can be okay if you make a good effort to keep the boots dry. Another option that you might wish to consider (and I have done this for safety reasons alone) would be to buy some slightly longer M5 screws and M5 nuts. Using the longer screw will give you some overthreading past the top of the T nut (for which there is space in the bed of the boot) and I have installed M5 nuts over the T-nuts. The M5 nut acts as pull-out security (I had a problem with metal fatigue fracturing the retaining flanges off my T-nuts with 3 of 4 gone on my rear boot before I discovered the problem) and also as a lock-nut to stop the screw from turning. This would give you the security of stainless steel without a fruitless search for SS T nuts.

Getting the T nuts out is less problematic than you might think. There are two situations: if you installed the T-nuts then the teeth are probably not very tenaciously set and inserting a screw and hitting it a few times with a hammer should easily remove the nut. If the boot came with T-nuts molded in, you are going to have some fun but it is quite doable. However, you need to acquire a punch that matches the OD of the shaft of the T nut as closely as possible. Using the punch, you can drive the T nuts through the plastic shell and into the interior of the boot without even damaging the plastic. Dave Morgan and I did a T-nutectomy (not to be confused with a castration) on my boots with no serious damage to the shell using the handle of a T-wrench (I subsequently acquired a set of punches). Of course the replacement T nuts will have to be the conventional type.

Good luck with it.

[mr_roboteye]

If you use a stainless fastener with a normal steel fastener, the normal steel fastener will corrode at a rate higher than if it was used with another normal steel fastener. BTW, many people think that stainless steel bolts are stronger than ordinary mild steel bolts, but stainless bolts are only about half as strong as the same bolt in normal zinc plated steel. In all seriousness, see if you can find them in titanium, about the same strength as steel fasteners, but totally impervious to corrosion.

later,

Dave R.

[D-Sub]

I live near a SUPER equipped hardware store called McFadden-Dale. They have every bolt imaginable in stainless, zinc, etc. I would be amazed if they didn't have t-nuts.

I have to go soon for some stainless fasteners for my bike. I can get you something if you need it.

[kjl]

I was unable to extract the tee nuts. I turned the boot upside down, braced it from the inside with a hammer handle, screwed a bolt halfway into the tee nut from the outside and whacked it with a sledgehammer. Not a hammer, a sledgehammer. I wasn't hitting it as hard as I could, since I didn't want to shatter or push the plastic to failure, but I hit it pretty hard, and I was unable to even get the tee nut to budge.

I may try again tonight with some help from the dremel, but I'm now kind of in that place where the tee nut obviously has enough integrity to hold the bolt even through sledgehammering, and I don't want to risk damaging my boot, or stripping the threads on one of the tee nuts making it very difficult to extract and repair in time for my next trip.

I think I will probably just ride on these tee nuts for the rest of the year and do a real extraction/replacement in the summer.

I hope these are not famous last words for my knee.

As Ben said, you must remove the liners from your boots every time you ride and dry both boots and liners. I turn my boots upside down and lean them against a hot water rad after riding.

Well, I always remove the liners, but I never take out the flat plastic insert that covers up the entire bottom of the boot (including all 4 intec nuts). Perhaps I should do that and turn it upside down as well.

[KingCrimson]

Well, I always remove the liners, but I never take out the flat plastic insert that covers up the entire bottom of the boot (including all 4 intec nuts). Perhaps I should do that and turn it upside down as well.

The footboard.

I was gonna joke about busting out the 10 pound sledge, but I guess I don't have to. You could get a long M5 (think 2 inch?) and kink it .5 inches from the bottom, thread it in, let it bind in the tnut at the kink. Figure out which way the "fins" go down into the plastic, and crank it against that way and try and bend the fins, it might thread out. Did this on a t-nutted plastic storage closet that didn't need the t-nut anymore :P

[Sinecure]

Ken,

Are these Head boots or Deeluxe/other? The T-nuts in the Heads are sort of molded in there as best I can tell. You could probably get them out, but I suspect it would be hard.

[Helmut Karvlow]

Ken, if they are not broken then leave them alone. you will make yourself more of a problem.

stainless will not react with steel as aluminum will. stainless threads will not stretch when tightened,they will gaul, that's why all stainless bolts have to have a lock washer to hold tight.

if it ain't broke don't fix it.

[csquared]

If you can't get them out with that much abuse, then there is probably not much wrong with them. I think if you just install longer M5 screws and put a nut on the extra thread that projects above the top of the T nuts, you should be fine (remember that the only force on the fastener is in pull-out).

You were obviously more diligent with drying your boots than I suggested. You shouldn't need to take the footbeds out. Turning the boots upside should make any significant moisture drain.