Screw Lengths for Threaded Inserts

[Angel]

New initiative:
I'd like help cataloging the various versions of look/rossi bindings. Can anyone suggest a good way to refer to the various versions? right now, I'm using
FKS geze 4 hole
FKS/FKX
FKS reissue

It appears that there are two versions of the reissue, perhaps it could be split into p18/FKS180 and p15/FKS150?

Reissue 18/180
Reissue 14/140

There are no Reissue 15s unfortunately. Although it is the same mounting pattern for both toe pieces, the screw head type and length are different for the 14s. 18s use the same size screw/head throughout (including front two heel screws). 14s use longer toe screws with a small head/button style in the front two screws and flat head in the rear two screws.

Looking at some of the older models, I think you are going to see this pattern in previous gens as well. Anything with 14 din and under has the larger screws, higher housing. 15 and up have the all metal toe.

[Angel]

Measured my screws. I'm using 10mm threads in the toe piece screws and the first two heel screws. I am using 16mm buttonhead in the rear two heel screws. I ordered the FKS reissue kit from Jon and had to modify the screw set to fit. I think it is more designed towards the 14s/140. Technically, right now I am using 14mm flathead and smallheads along with the 10mm buttonhead, but the thread depth is the same on each. I had to grind down the flatheads to get a fit. I would use 10mm buttonhead for all toe screws and the first two heel screw. I would use the 16mm buttonhead for the rear two heel screws. There is no need for smallhead or flathead screws with the 18s/180s, unlike with the 14s/140s. Will post pics later.

Modified screws to fit 18s/180s. First three all have the same thread length and are interchangeable within the toe piece holes and front two heal piece holes.

[jondrums]

Thanks a ton Angel. That really clears up some confusion. I don't have the reissue 18/180s. I updated the front page and doc to reflect your setup.

I'm guessing that we probably need to split up the FKS/FKX category into 12,14,15,18 as well. Anyone have more input on this topic?

[jondrums]

Added Look PX14

[auvgeek]

Anybody else have problems with the re-issue FKS screw kit with an FKS 140? If the kit seems to work for others, I'll take it up with jondrums privately. But the smallheads sent with the set are much too short (don't extended past the binder).

I'm happy to measure all the screws and get what I think are the correct lengths, but I don't want to waste my time if everyone else thinks the kit is correct and maybe some screws just got mixed up or something.

[jondrums]

Can you list the fasteners you have, and the fasteners you think you need?

[auvgeek]

Sure. Will try to do that later tonight or tomorrow. I don't have a pair of digital calipers at home, but I may borrow them from work. If not, I'll get as accurate as a can with a little millimeter ruler.

[critical-motion]

Just measured screw length for Look PX14 Racing (short, worm drive heel) using my digital calipers. I think the PX14 you have listed is the "Racing" version like mine because the screw lengths listed by jongdrums () are similar to what I measured:

Toepiece:
16mm (14mm) smallhead
16mm (16mm) Flathead

Heel:
10mm (8mm) buttonhead
26mm (25mm) buttonhead

Photo of PX14 measured:


A rare, non-worm drive PX12/PX14 is available without without a lifter but I think it was a European marked model and not the one you have listed:


PX12 and PX14 (non-worm drive heel) generally come with a lifter and use longer screws. I measured my PX12 w/lifter and found:

Toepiece:
22mm smallhead
20mm Flathead

Heel:
18mm buttonhead
30mm buttonhead

PX12 measured as pictured:


I add the caveat that I have not yet tested these screw lengths but will be doing so in the next month or so.

[dschane]

I'll keep it at 14mm for now, since that should still get 4mm of engagement. If someone else can confirm a mounted working setup with 16mm, I'll update it.

I had used Alpinord's revolution method . . . I installed the inserts slightly deeper than flush and had approx. 5.75 revolutions with the 16mm flathead screws, so I went with those (I could get only 3 revolutions with a 14mm flathead screw). I have about 10 days of use on the X2 bindings installed with the 16mm screws and all seems perfectly fine.

[skis_the_trees]

Jon - I am questioning if the Dynafit Vertical row is correct? I have verticals mounted on (my home-made) swap plates and they take 4 M5x10 button heads for each heel piece (=8 total). This column is not demarcated and I think the flat heads are erroneously marked in the chart instead.

[Alpinord]

A customer reminded me about a 're-tapping' technique after you modify a screw's length. This was added to post #7:

When you cut off or grind down a screw, often the end needs deburring and sanding to allow for smooth threading. One technique is to put one or two nuts onto the screw before you cut, grind or file the end. After the modification remove the nut(s) to 're-die cut' the screw end.

[Angel]

Just to add a little footnote. I drilled some skis a few weeks ago, but didn't tap because I was waiting for more inserts and my guide block. I began tapping about two weeks after drilling and noticed after the first few holes that it didn't seem to be tapping as far as it should. Sure enough the wood had expanded. I redrilled the holes I hadn't tapped yet and no problems there, but I'm left with dremmling three inserts (less than a mm high) to make them flush. Providing I don't want to helicoil them, which I don't. Balls.

[lynchdogger]

Hey Jondrums,

Thanks for the quick shipment. Any info for screw lengths for Hammerheads - older blue model (forget exact year maybe 2005-06?). Thanks.

[jondrums]

Any info for screw lengths for Hammerheads - older blue model (forget exact year maybe 2005-06?). Thanks.

I have notes that suggest the following:
22 Designs: HammerHead qty16 buttonhead M5x14

I would appreciate a confirmation if this is right or wrong.

[jondrums]

I have verticals mounted on (my home-made) swap plates and they take 4 M5x10 button heads for each heel piece (=8 total)

A you sure these aren't comforts? I have FT12 verticals and they take flatheads in the heels.

[jondrums]

Just measured screw length for Look PX14 Racing ... I measured my PX12 w/lifter and found:

awesome, thanks! let us know when you've tried the PX12/14 lifter lengths out.

[SaSSafraS_LTK]

So apparently at some point the rear heel screws on the Salomon 914 were changed. I was mounting a pair of 2007/2008 vintage 914 bindings (the ones with the sliding AFD). The packaged button 25mm buttonhead screws were about 12mm past the base plate. (The ones in the photo are actually backups from the hardware store, but other than being phillips + slotted instead of 3mm allen are identical.)

I cut about 8mm off, leaving a 17mm screw, and they seemed about right, with around the minimum of 4mm protruding into the insert. I think you might have to either split the 914/916/STH916 kit into two, based on year or include 4 more 16mm or 20mm button heads in it.

The rest of the screws seemed fine.

Edit: Actually, on further examination, the 14mm flathead screws for the rear toe holes are also too short. They only have about 2mm of protrusion. The ideal kit for these would be:

4x 16mm small head (front toe)
4x 18mm flat head (rear toe)
4x 12mm flat head (front heel)
4x 20mm button head + 2mm washer (rear heel)

[SaSSafraS_LTK]

If you use two nuts on an M5 screw to install the inserts you can use a lot more force than you can with Jondrum's tool (especially if you're using a big phillips M5 screw instead of the 3mm allen head). If your holes were close you could probably have just forced them in that way.

I had to do that on two of my holes that I accidentally drilled too deep then intentionally tapped short because I was scared of spinning them too far down into the hole.

Just to add a little footnote. I drilled some skis a few weeks ago, but didn't tap because I was waiting for more inserts and my guide block. I began tapping about two weeks after drilling and noticed after the first few holes that it didn't seem to be tapping as far as it should. Sure enough the wood had expanded. I redrilled the holes I hadn't tapped yet and no problems there, but I'm left with dremmling three inserts (less than a mm high) to make them flush. Providing I don't want to helicoil them, which I don't. Balls.

[NatEE]

I'm attempting to figure out what I need for speed radicals, so I put some calipers on the heel-piece to see if I could clear that up.

Based on the above method, for the heels the numbers were: 11.6mm - 7.6 mm + 5mm = 9 mm. So either a 8mm or 10mm screw should work, but at the ends of the acceptable tolerance range.
If you can find the right 1mm washer to put under a 10mm that might be ideal, but a standard flat washer is probably slightly too large to fit in the countersink in the plastic (which is just slightly under the nominal 10mm OD for the washer).

Regarding radical toe-pieces, I was under the impression, both from store fondling and posts here, that the metal plate on speed/ST/FT toe pieces was the same. It does look like the countersinks on the speed radical are a bit too small for standard flatheads (thus making smallheads ideal), but are the screws/countersinks on the other bindings actually different?

[jondrums]

Based on the above method, for the heels the numbers were: 11.6mm - 7.6 mm + 5mm = 9 mm. So either a 8mm or 10mm screw should work, but at the ends of the acceptable tolerance range.

I found that it depends on how far the insert is installed whether a 10mm works with the radical speed, so I updated the length to 8mm. Can anyone confirm if the radical should be moved down to 8mm as well?

[dbcooper]

I had the same problem with reissued FKS 140s as 'auvgeek'. My bindings required 18mm smallheads for the front of the toe piece and 16mm flatheads for the back.

[four0sicks]

I just got back from the hardware store, and struck out finding screws to fit 2 Designs AXL bindings. The problem is the recess on the binding for the screw heads. Most pan heads are too big by a fraction of a millimeter. I fond some hex drive pan heads that fit, but they were 1 mm too long, and the M5 washers are too big for the recess in the binding as well. Does any on know a special fastener that may work? I am about to get out the Dremel, but really don't want to take power tool to a brand new binding. Any suggestions would be great. Thanks.

I will be sure to post back if I find something that works.

[NatEE]

I found that it depends on how far the insert is installed whether a 10mm works with the radical speed, so I updated the length to 8mm. Can anyone confirm if the radical should be moved down to 8mm as well?

Thanks for the clarification, I agree that 8mm is the better option in this case. I only have the speed radical so I can't confirm the heels for the regular radical, but it would not surprise me if they are a bit taller due to the brakes.

I just got back from the hardware store, and struck out finding screws to fit 2 Designs AXL bindings. The problem is the recess on the binding for the screw heads. Most pan heads are too big by a fraction of a millimeter. I fond some hex drive pan heads that fit, but they were 1 mm too long, and the M5 washers are too big for the recess in the binding as well. Does any on know a special fastener that may work? I am about to get out the Dremel, but really don't want to take power tool to a brand new binding. Any suggestions would be great. Thanks.

Have you tried socket heads? Head diameter should be ~1mm smaller than the standard hex drive pan heads. The heads are a little bit taller though, but if you can get your hands on some low-profile socket heads it should not be much taller (definitely available online if you have to go that route).

Rather than take the dremel to the bindings, I would suggest trying to file down the screws a bit. Stick the screw in a rotary tool (drill or dremel, may need to use nuts or something to hold it), and file/sand off a bit of the head. There might be some other considerations doing this that someone who knows more about machining things can elaborate on.

[harpo-the-skier]

Jon, you say:

"*Measure the screw itself as well. Subtract the protrusion length from the length of the screw. Add 5mm to that length. Find the closest size fastener that is within 1mm of that number. In this example, 13mm - 9mm + 5mm = 9mm. Either an 8mm or 10mm flathead would be appropriate for this binding."

How does that calculation change for Puder Luder Quiver Killers? I am a loyal bindingfreedom customer but have some left over QK's I want to use.

[jondrums]

At one point quiver killers had closer to 5mm of thread depth (instead of 6mm minimum depth for bf), so if I were you I'd use the shorter screw option with qk. Anyone else have more recent info? Maybe Terry can tell us how many turns of threads are in the most recent version.