Tapping BF inserts on-ski

[angrysasquatch]

I recently installed some BF inserts on my Cho Oyu. I found today after the epoxy had set that one of the inserts was not actually tapped on the inside.



Upon heating and trying to back it out, the metal failed and left me with not much purchase with the screwdriver for extraction. So, try to tap it (tap and bottoming tap) to make it usable, use a reverse drill bit to extract? Not sure but I'm a bit mad at the product and myself, I noticed a few that were missing internal threads and some with incomplete cutting on the external threads. Dynafit race binding, no fore-aft adjustment so another set of rear holes would mean re-doing all of them...

[Lindahl]

Sounds like the woes of selling BF to SVST? I'd just tap the blank insert, personally. Makes the most sense.

[adrenalated]

Yeah, I've had a few of those, and well before the SVST days.

You tap metal just the same way as you tapped the holes in the ski for the inserts. You need an M5 X 0.8 bottoming tap and a tap handle. Go SLOW, and after every ~1/2 turn, turn the tap in reverse (this breaks the chip off the tap, otherwise the tap will jam and screw up your threads). It's a good idea to have some oil to lubricate the tap as well, though I've done it without lube (slow pitch).

BF should hook you up with a tap for free, IMO.

[grinch]

tap it or heat then use an "easy out"(its a reverse thread bit for extraction). ez out is ,while not necessarily ez and require a bit of fn around, is probably easiest. I have a few heli coils from bf , in worst case scenario, and the tap and bit for them if you need them . should allow you to keep those holes for your fiddle races. you're just across the pass from me so I could just send m over and just send the bit and tap back. I'd try tap first and then ez out and I'd wager you'll be gold with those

[~mikey b]

Heat with boiling water poured over it. Softens epoxy and surrounding material.

[timmaio]

I've noticed this on one out of roughly 200. Thankfully caught it before installation(and my method of installation with a M5 socket cap, 2 nuts and a washer wouldn't let me install one with this defect.)

[shafty85]

These have been the exception, not the rule. I've yet to be that upset about it because, fortunately, I noticed it before I installed the first time. I now always check that the inserts are properly threaded both inside and out. If I received a batch that had a large number of improperly/poorly threaded inserts, that wouldn't be cool. But, no companies product is 100% all the time.

Issues I've experienced include:

- No threads on the interior
- Interior threads just farked
- Exterior threads thickened, more like they had must scored the exterior, cutting very thick threads, rather than cutting proper threads

Again, the exception (so far), not the rule.

[GeezerSteve]

If you try to tap it in place there's a good chance it'll result in a spinner. 303 SS (or whatever alloy it is) is soft stuff relative to other metals but hard compared to a ski core. I think the torque required to tap it in place very well may exceed the torsional strength of the insert/ski bond. IVO the above, I'd heat it, pull it with an EZ-out and install a new insert.

[adrenalated]

If you try to tap it in place there's a good chance it'll result in a spinner. 303 SS (or whatever alloy it is) is soft stuff relative to other metals but hard compared to a ski core. I think the torque required to tap it in place very well may exceed the torsional strength of the insert/ski bond. IVO the above, I'd heat it, pull it with an EZ-out and install a new insert.

I've tapped at least 3 in place with no spinners. If they were epoxied well to begin with they will be fine.

[angrysasquatch]

Thanks guys, hopefully I can find taps in this town (literally nowhere has a #3 posi for sale). I thought about overcoming the epoxy bond, but if that happens it's a good start #2, extraction anyways. These are pre-svst, bought them direct from binding freedom. Will let ya know if I need to go that route, thanks grinch

[1000-oaks]

I'd heat it up with a soldering iron until you hear the epoxy crackle a bit, then back it out with an easy-out and replace.

And that's even though I have nice metric taps, which you won't find around town. Harbor Freight taps suck, and Craftsman are okay but not all that great. Insert M5 thread is pretty fine, so you want a high-quality tap like a Guhring. Two of them actually, one taper tap to get the threads started, and a bottoming tap to finish it. Probably $40 worth of taps for a good brand. Try Drillspot, Amazon, MSC, or Zoro.

[adrenalated]

Thanks guys, hopefully I can find taps in this town (literally nowhere has a #3 posi for sale). I thought about overcoming the epoxy bond, but if that happens it's a good start #2, extraction anyways. These are pre-svst, bought them direct from binding freedom. Will let ya know if I need to go that route, thanks grinch

Industrial supply. You're unlikely to find an M5 tap at a typical hardware store.

[GeezerSteve]

I've tapped at least 3 in place. . . .

You installed at least 3 inserts lacking interior threads without noticing the obvious defect? WTF?

[adrenalated]

You installed at least 3 defective inserts (lacking interior threads) without noticing the defect? WTF?

Yeah. Shit happens when you're installing 700+ in a season.

[jondrums]

Sounds like the woes of selling BF to SVST? I'd just tap the blank insert, personally. Makes the most sense.

Definitely not. Most likely this shipment came from before we sold, so I'd have to say that's my fault! It did happen a few times in our latest batch of inserts, and I tried to go through and sort them out but obviously didn't get them all. I'm sorry about this.

SVST put one of their guys on sorting through the inventory one by one to make sure this never happens again. Quality will improve, I can be sure of that.

In terms of a repair - I suggest that you get either an easy-out or left hand drill bit. heat up the insert with the tip of a soldering iron, then remove with the drill on reverse. Other suggestion is to get a M5 tap and cut the threads into the inserts.

[Muggydude]

I've found that a good way to check your inserts and make sure you have all the screw lengths correct is to put the machine screws though the bottom of the bindings and then thread on the inserts on the bottom (before installation). Should be snug- and then you can make sure all the internal and external threads are fine. Once all the holes are tapped just take them off one by one and install

[Muggydude]

Haha probably hit that one right on the head. I also wipe down each insert and screw with some rubbing alcohol to remove anything left on from the machining process too...

[1000-oaks]

^ Yeah, unless I'm buying a large quantity, I usually run a nut down every bolt I buy to make sure the threads are good - OCD.

I definitely check insert threads with a screw before epoxying them into a ski though, don't want to deal with any time-consuming f-ups. I put that in the same class as "measure twice, cut once" - not OCD.

[Ivan Oder]

I'm OCD with my inserts, I check the threads on the inside and the outside. Run an M5 screw in there when and note any resistance, depth issues etc. Order more than you need and throw the questionable ones back in the bag.

[angrysasquatch]

Tapping it was pretty easy, borrowed some off a buddy. Start with standard, then bottoming tap, done.

[grinch]

small victory for man vs machine. good to know

[bogusbill]

As Jondrums pointed out those inserts are from original BF stock. SVST was not satisfied with the overall quality of the existing inserts and has taken it upon themselves to have the inserts produced in the U.S. with stricter quality control. These issues will be a thing of the past.

[angrysasquatch]

Jondrums- can the original allen head screws still be bought through you or SVST? Might need odds and ends to round out this year's setups, and don't want a mixed posi/allen set of screws holding the bindings down.

[timmaio]

If jondrums does not sell those anymore, you can buy them from Fastenal. Very inexpensive and I'm pretty sure they are the exact same screws Jondrums sold.

[jondrums]

I have a huge stock of old allen head screws. I cannot take the time to part them out right now - if I had that kind of time I would still be running the business. I was planning on selling the whole lot on gearswap one of these days.