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Author Topic: Edea screw substitutes  (Read 7350 times)

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Offline Bill_S

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Edea screw substitutes
« on: March 29, 2022, 11:57:02 AM »
I haven't worked much with Edea skates yet. Edea specifies their own double-helix screw for their plastic soles. Here's a link to their page about their special screws...
https://edeaskates.com/en/ice/why-edea-is-so-special/more-confidence/blade-mounting-screws/

Frankly, I wouldn't put a zinc-chromate plated screw into a new boot. The photos on their page show screws of marginal production quality too.

If I were to mount a blade onto a Edea boots, I'd use a stainless steel version of those screws - https://www.mcmaster.com/plastic-screws/high-strength-410-stainless-steel-rounded-head-thread-forming-screws-for-brittle-plastic/

This leads me to my question - has anyone here replaced damaged or corroded Edea-supplied screws with something like the stainless screws in the link? If so, how close is the thread pitch, and are there any notable differences in the thread angle?
Bill Schneider

Offline supersharp

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Re: Edea screw substitutes
« Reply #1 on: March 30, 2022, 12:13:09 PM »
Thanks for bringing this up, Bill.

 I have been thinking along the same lines as you- I might order some of these to compare. So many of the boot manufacturers are using plastics for sales now, and the standard screws I've always use are more likely to strip or crack the soles.

Offline Bill_S

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Re: Edea screw substitutes
« Reply #2 on: March 30, 2022, 01:22:50 PM »
Without having direct experience, I think that a careful comparison is about the only way to see how interchangeable they are.

If you undertake this, I would be very grateful.
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Offline Kaitsu

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Re: Edea screw substitutes
« Reply #3 on: March 30, 2022, 01:42:02 PM »
Edea´s boots are very popular here in Europe, so I have seen quite may pairs of them during the years. In my opinion zink coated screws are major problem only on boots with leather soles. Even some boots does have protective layer / film on sole, which should prevent leather to suck moisture, it does not help on screw issues. Even I used glue, moisture will enter in to the screw holes and cause severe corrosion to the screws. I do not know why the the leather soles are so bad for the zink coated screws, but its almost same like using zink coated screws on impregnated wood. I do have acid resisting stainless steel screws for leather soles, but no-a-days I do not use them so much, when also Risport recommends to use only their screws which are Zink coated. Most of the boots here are either Risport or Edea.

In Edea boots I use Edea screws. You can see some oxidation after some years, but hardly ever I see any more severe damage. I believe it is thanks to full plastic soles which are not sucking any moisture. Due this property, I love Edea boots. Does the Edea boots have any other benefits, that can be another story. At least too often there is huge gap between the blade and sole, which causes own troubles.

It happens way too often that the green screw bag which should be in the same box with the boots, has been lost before boots and blades arrives to me. For this reason I have purchased these screws in bigger bags so that we do not need to wait several days to get screws from the skate retailer. Before I did have my own stock of Edea screws, I use those stainless screws, zink coated screws or screws which are delivered together with blades. I have never seen any issues even the screws has been "wrong type". In the other hand all skaters are basically children's with less weight and lower grade jumps. I would ensure that screws are long enough so that they enter to that white plastic "insole" in toe plate area.

Air is pretty dry in my country, so I cannot know how Edea screws works on areas which has more tropical ambient conditions than we have. Personally I do not have any plans to change using stainless screws on Edea boots. On Risport boots I have considered stainless screws.

 

Offline supersharp

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Re: Edea screw substitutes
« Reply #4 on: March 31, 2022, 12:04:30 PM »
I live in a rainforest, so I am constantly dealing with rusting screws.  Only a couple of skaters wear Edea boots here, one who has left for college and one skater who moved from Jackson to Edea in October and has decided to go back to Jackson because she does not like the feel of the Edea boots... so I don't have much experience seeing if the Edea screws corrode.  Good to hear Kaitsu’s experience on this.

I see a lot of rusted screws on the older Jackson boots with plastic soles (Artiste, Mystique) and also on the newer PVC soles.  it might just be that our climate is particularly hard on skates.  I use stainless screws on everything that I can, but I’m finding that the plastic soles seem to strip very easily, so the hi-lo thread stainless screws seem like they would be worth trying.

McMaster-Carr charges outrageous shipping to Alaska, unfortunately, so I will have to do some shopping around to see if I can find the screws elsewhere.

Offline Query

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Re: Edea screw substitutes
« Reply #5 on: April 01, 2022, 04:24:14 PM »
Do I understand correctly that Edea uses their double helix screws so that they can use thinner sole boots, to save weight?

Perhaps double helix screws make sense to increase surface area contact to those of you with an engineering background. But it isn't intuitively obvious to me that you couldn't do the same thing by using more threads/inch.

At one point in time, an Edea rep told me they drilled all the way through, which I thought meant they used a nut and washer inside the boot to secure a bolt, which I would have thought meant they don't need threads, unless the threads are mostly there to slow moisture penetration, or to add extra hold. Maybe that isn't true now? Or did I guess wrong, or has that changed?

BTW, fascinating that Alaska has rain forests. It must be so beautiful there, a place of great contrasts. Do you love it? Do you ever skate outdoors?

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Re: Edea screw substitutes
« Reply #6 on: April 01, 2022, 07:21:12 PM »
Query - These screws are sometimes called Hi-Lo screws because of the double threads. If you want more information about them, try this link - https://www.wclco.com/threaded-fasteners/screws-for-plastics-and-other-low-density-materials/hi-lo-fasteners/

supersharp - I hear you about McMaster-Carr shipping costs. Even here it is very high compared to most vendors, although I'm sure it doesn't compare to what you experience in Alaska. In my case, one benefit for  shipping $$$$ is turnaround time. I usually have orders to my door in less than 24 hours after ordering from McMaster. Unfortunately, there is no option for slower shipping if I want to save money.
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Re: Edea screw substitutes
« Reply #7 on: April 01, 2022, 07:50:15 PM »
At one point in time, an Edea rep told me they drilled all the way through, which I thought meant they used a nut and washer inside the boot to secure a bolt, which I would have thought meant they don't need threads, unless the threads are mostly there to slow moisture penetration, or to add extra hold. Maybe that isn't true now? Or did I guess wrong, or has that changed?
You got it wrong.  Drilling through the sole was not intended for a nut and bolt.  The sole is thin, so you need to maximize the depth of material for the screws to bite into.  And unlike standard sheet metal screws, which have a pointed tip, Edea screws have a blunt tip to minimize risk of piercing the footbed.

Offline Kaitsu

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Re: Edea screw substitutes
« Reply #8 on: April 02, 2022, 06:39:24 AM »
Picture of different screw types added

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Re: Edea screw substitutes
« Reply #9 on: April 02, 2022, 07:46:30 AM »
Picture of different screw types added
The Edea screws are obviously different from standard sheet metal screws.  But do you notice anything different about the Risport screws (that is not evident from the photos)?

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Re: Edea screw substitutes
« Reply #10 on: April 02, 2022, 08:11:37 AM »
supersharp - I hear you about McMaster-Carr shipping costs. Even here it is very high compared to most vendors, although I'm sure it doesn't compare to what you experience in Alaska. In my case, one benefit for  shipping $$$$ is turnaround time. I usually have orders to my door in less than 24 hours after ordering from McMaster. Unfortunately, there is no option for slower shipping if I want to save money.
Yeah, I've used McMaster-Carr since I was a grad student working on my dissertation project (and later when I was working in industrial R&D).  This was in the Pre-InterNet days, when they had a thick printed catalog.  They are primarily a business-to-business (B2B) supplier; large in-stock inventory and quick delivery are paramount.  The only inexpensive delivery to Alaska is via US Post; but they use private carriers.  And there are even more unexpected $$$$$ delivery charges if the order ships in multiple packages (e.g., items shipped from more than one warehouse, or if an item is temporarily out of stock):  there is a (relatively high) minimum delivery charge per package.  Quite a shock for shoppers weaned on Amazon.

Offline Kaitsu

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Re: Edea screw substitutes
« Reply #11 on: April 02, 2022, 12:06:24 PM »
But do you notice anything different about the Risport screws (that is not evident from the photos)?

No, I do not see any secrets on them. Thread pitch in Risport screws is more coarse and they are slightly longer than Wilson screws. Conical head is also smaller than what I used to see. nothing else. I would say that correct length is most important  feature, which secures proper blade mounting.

Finally Edea has implemented screws also for composite framed blades. It has been a bit scaring to see how conical head Edea screws has been used example for JW Revolution blades
https://edeaskates.com/en/ice/blade-mounting/

https://edeaskates.com/en/ice/why-edea-is-so-special/more-confidence/blade-mounting-screws/

Offline supersharp

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Re: Edea screw substitutes
« Reply #12 on: April 02, 2022, 02:33:56 PM »


Perhaps double helix screws make sense to increase surface area contact to those of you with an engineering background. But it isn't intuitively obvious to me that you couldn't do the same thing by using more threads/inch.

BTW, fascinating that Alaska has rain forests. It must be so beautiful there, a place of great contrasts. Do you love it? Do you ever skate outdoors?

More threads per inch makes the space between threads smaller, which seems to lead to stripping much faster on the new Jackson soles. The hi-lo screws have a wider spacing on the “hi” threads, leaving more structural integrity in the plastic.

Alaska is an enormous state with many sub-climates.  All of them are beautiful- I’m in a lush forested area and farther northwest there are some desolate areas with a stark beauty that is hard to describe.  I’m sure there is similar terrain on many northern countries.

Yes, I skate outside when I can, now that I have an extra pair of skates with older blades that I don’t have to worry about running over grit and other debris.  It’s pretty glorious to be outside but of course the ice quality is quite variable.  There had been talk about adding a seasonal outdoor sheet of ice next to outer rink, but it is next to a beach (called Sandy Beach) and when the winter wind blows, there is just too much sand that would be deposited on the ice. 

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Re: Edea screw substitutes
« Reply #13 on: April 02, 2022, 03:26:03 PM »
One difference that I see between the Risport and Wilson screws is that the Risport flat-head screws are a larger diameter than their round head screws. I wonder why they chose to do this?

In the leather soles that I have attached blades too, I use smaller size #6 screws to start with, and only need to go to a larger diameter #8 screw if someone brings a skate to me with a stripped thread in the leather.

In a rough approximation, the Risport screws would correspond with #6 and #8 screw sizes in the US.
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Re: Edea screw substitutes
« Reply #14 on: April 03, 2022, 07:40:09 AM »
No, I do not see any secrets on them. Thread pitch in Risport screws is more coarse and they are slightly longer than Wilson screws. Conical head is also smaller than what I used to see. nothing else. I would say that correct length is most important  feature, which secures proper blade mounting.
Thanks for the details of the Risport screws.  I recently replaced blades for a friend of mine.  Her boots were Risports, which I've never worked on before.  I had previously read on the Risport website that they used special screws.  There was no photo, so I thought, "Oh, they must be like the Edea screws."  But when I demounted her old blades, the screws appeared to be regular sheet metal screws (I didn't inspect them in detail).  I thought maybe her tech hadn't used the special screws.  But since she had been skating with them for about a year without problems, I plugged the old holes, drilled new holes, and installed stainless-steel sheet metal screws for her new blades.  So, thanks to your post, I have no concerns over long-term issues with the screws I used.


Offline Query

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Re: Edea screw substitutes
« Reply #15 on: April 03, 2022, 12:08:21 PM »
OK, it makes some sense double helix screws are better in many respects. Why aren't they more common?

BTW one of Kaitsu's Edea links

https://edeaskates.com/en/ice/blade-mounting/

is fairly informative, but a bit hard to understand, because the English language grammar and semantics are a bit unclear, and the idea that the blade length should only depend on the outsole length and geometry, not the foot,  has never made sense to me. (Though a Klingbeil rep [I think] once told me that on a properly designed fully custom boot, the optimal length for the foot matches the optimal length for the boot.) They initially say that it should be determined entirely by the boot - but the comments make it sound like they might be talking about aligning with control points on the foot.
 

So I sent them an inquiry:

Quote
At https://edeaskates.com/en/ice/blade-mounting/ you say
"Firstly, we need to choose the correct blade for our discipline and skating level.
Whatever the discipline, the length of the blade is determined by the size of the boot. This allows the contact points to line up with the “active” parts of the blades.
The rocker with the ball of the foot and the center of the heel blade with your heel for the best control and quickest response.
Longer blades do not line up, slowing response, reducing control and causing possible injuries as you overcompensate."

The meaning of this is unclear. Perhaps it is an English language translation problem? It would be helpful if you would clarify the meaning.

Is 'This allows the contact points to line up with the “active” parts of the blades.' meant to imply that the mount length is partly a structural issue for the boot and blade, rather than just a control issue?

Am I correct that you don't offer full custom boots, so it is impossible for some people to get Edea boots in which the center of the foot heel is aligned precisely with the center of the boot heal, and the center of the ball is aligned precisely with the indicated  point on the boot? Should such people get a blade length which is a compromise between that determined by the boot length and geometry, and the foot length and geometry?

E.g., Is the forward vertical line meant to pass through both the ball of the foot, and the transition point between the main blade rocker, and the spin rocker?

I doubt they will respond, but it is worth a try.

Does anyone know if the Italian grammar and semantics makes things more clear?

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Re: Edea screw substitutes
« Reply #16 on: April 03, 2022, 02:10:39 PM »
Since McMaster-Carr is mostly B2B, perhaps they sell stuff to some Alaska retail outlets - and you could cut shipping costs by buying or ordering through them, so that it was part of a larger order?

You could ask McMaster-Carr for local distributors, by contacting at https://www.mcmaster.com/contact.

Also, https://www.trustedparts.com/en/manufacturers/mcmaster-carr might list some of their distributors.

If you know the people at a local pro shop well, maybe they would sell you the Edea screws at a reasonable price. I've bought or even been given other screws at a shop where I knew the people.

I suppose your area might be too remote for Edea to send reps to local skate competitions? If not, maybe you could contact them in advance and ask them to bring some screws?

(Salt water) marine market screws are generally much more corrosion resistant, but the steels they use are softer. I don't know if that matters for this application. I've been tempted to use them. There are even aluminum (very soft) screws, and titanium screws (outrageously priced, but can be pretty strong), which are also more corrosion resistant, sometimes used in marine applications, like sea kayaks, though I've had even aluminum bolts corrode badly on sea kayaks. But if you sometimes skate on water with some salt in it, that is a marine application.

Offline supersharp

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Re: Edea screw substitutes
« Reply #17 on: April 04, 2022, 12:35:58 PM »
Query—There is no pro shop here, unfortunately.  I’m probably the only person in town that knows what an Edea screw looks like (which is not surprising since everyone else only sees the screw heads).  We don’t have any big competitions here, so no boot or blade reps ever come. Good idea to see if any of the industrial shops here order from MMC. We used to have a Fastenal store, but it closed when Covid hit

Offline Query

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Re: Edea screw substitutes
« Reply #18 on: April 05, 2022, 02:12:11 PM »
Oh.  I assumed Juneau was a dense population center.  Just looked it up. My bad.  Presumably Juneau's Play It Again Sports doesn't carry the screws you want. You could put "Juneau's Leading Skating Pro Shop!" on your mailbox, maybe you could buy at wholesale (might need a business license), but that wouldn't overcome shipping costs.

I'm out of ideas.


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Re: Edea screw substitutes
« Reply #19 on: April 07, 2022, 05:05:05 PM »
Juneau's Play It Again Sports closed about 5 years ago.  Current population is about 32,000, so we are not tiny but are isolated.  We have a funny mix of some things you might not expect (capital city effect, we need to be able to keep the legislature entertained) and a lack of things that are surprising at times.  Like no skate shops even though our ice is packed with hockey players and figure skaters.

I have a business and a business license, but I'm not buying in quantity.  However, I did manage to order the stainless hi-lo screws from MMC and have them shipped to my daughter's house in Washington for only $10.  If she gets sick of looking at them, she can put them in a flat rate box and ship them to me for under $20.  Otherwise, I will pick them up and bring them back in my luggage on my next trip or she can bring them up if she comes here sooner than I go down there.

I put 4 boxes of 100 screws each (panhead and flathead in 1/2" and 3/4") and the shipping to Juneau was going to be $99.  Ouch!

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Re: Edea screw substitutes
« Reply #20 on: April 07, 2022, 10:13:49 PM »
Edea responded to my questions about blade length:

Quote
You emailed Edea about mounting and questions about Edea boots, they sent the email to me.
So I believe you are overthinking the blade length for Edea boots. Here at SkatesUS, we have a chart that tells you what the largest blade should be on an Edea boot. Most coaches prefer that the largest blade should be used for a freestyle skater. As far as centering the blade, a good tech should know how to see the center of the sole of an Edea boot to get a proper temp mount. As all blades should be temp mounted first and have the skater skate on them to see if they need to be moved and/or adjusted.

Second, Edea does not offer custom boots because all Edea boots are custom shapeable. So you can get a custom fit from a stock boot. A lot of SkatesUS dealers can custom shape Edea boots for a skater with the proper equipment. Here is a link to the SkatesUS dealer list. Just find a dealer in your area and look for the yellow blowdry icon when clicking on the dealer's name. That means they have been trained by SkatesUS for shaping. Dealers are listed by State.

https://skatesus.com/ice-skating-dealers/

Blade Chart
https://skatesus.com/product/ice-fly-90/

Let me know if you have any other questions.

Thank you
--
Tim Gordon
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Offline supersharp

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Re: Edea screw substitutes
« Reply #21 on: April 07, 2022, 10:47:25 PM »
Hahahahaha.  "I believe you are overthinking the blade length for Edea boots".   

Possibly, but it does seem a bit like this response is underthinking the lineup of the blade with the boot.  But I think that answers your question in a different way--just put the longest blade on them possible and go to the hairdryer icon people to get them shaped for your feet.  That is as custom as they get.  I know there is a limit to the amount they can stretch the boot shell, which is also true for ski boots.  If you aren't close to the width or length of the boot, they probably aren't going to work. 

Thanks for sharing this response, it is always interesting to see what the "marketed" response will be.

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Re: Edea screw substitutes
« Reply #22 on: April 07, 2022, 11:58:20 PM »
What I probably shouldn't say, since I haven't seen recent Edea boots, is that AFAIK, you can't reshape the soles, which is to me one of the most important parts of custom boots.

In particular, as far as I understand it, and I could be completely wrong, the uppers of their boots are constructed much like fiberglass or carbon fiber boats - a plastic resin bonds fibers together. And, again I could be completely wrong, I think their reshaping technique involves heating the the resins to the point of being "plastic" (i.e., deformable, creating new bonds as the old ones are broken), then stretching the material to shape by forcing the fibers slide against each other. But if I understood what the fitter said, the soles can't be deformed that way.

Or maybe everything has all changed for "microfiber" boots.

When I had an Edea fitting (years ago, and not with microfiber construction), I think by the person who owned SkateUS (he came to a competition, and customized one person after another in fairly rapid succession), I was told that my feet were too different in shape (wide toes, narrow heels, and of a size about halfway between their stock sizes) for reshaping to work. So there may be some limits.

Please don't take my skepticism as authoritative. Maybe they CAN do a good job now, and their boots can be made to perfectly fit almost everyone. That would be nice.

I thought a bit more about these double helix (hi-lo) screws. Much of the indicated advantage over just using more threads/inch in a single helix thread follows from the narrower angle (30 degrees vs 45) in the thread shape. You could replicate that angle in a normal thread - but maybe that would go against the conventions that people who use screws expect. I.E., the standard that people expect is a particular thread shape, (just like a pan head screw is expected to have a countersink, and a round is not). Whereas the convention for hi-lo screws is the narrower thread angle. People don't expect to have to check the thread angle when they replace a screw.

I do see why you can screw them in more quickly, because it requires fewer turns to screw them in. But perhaps abandoning the self-tapping feature - by having a blunt end - eliminates the time advantage.

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Re: Edea screw substitutes
« Reply #23 on: April 08, 2022, 01:05:03 PM »
When you mount Edea boots, you remove the insole and drill all the way through the sole. The front sole plate screws go most of the way through the sole, so for Edea boots, it is necessary that they be blunted to keep the screw gripping all the way to the inside of the sole. And helpful to have no pointy things stabbing into your insole as well.

For all boots, drilling a pilot hole for the screws is important.  For the newer synthetic soles, you can crack the sole if the pilot hole is too small.  On leather or LCL soles…I have seen many mountings with no pilot hole. The screw takes up space and the leather can only compress to a modest extent.  Not creating a void for the screw causes the leather to bulge, making your sole slightly lumpy. It also means you have less control over the angle the screw takes, which can result in tilted screw heads applying unnecessary tension on the boot and sole plate.  I use pointed stainless screws on leather and I use a smaller and shorter pilot hole for the front sole plate screws so the point beds into solid leather at full depth.  The stacked leather heels are much stiffer and require a bigger pilot hole.

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Re: Edea screw substitutes
« Reply #24 on: April 08, 2022, 02:21:54 PM »

I thought a bit more about these double helix (hi-lo) screws. Much of the indicated advantage over just using more threads/inch in a single helix thread follows from the narrower angle (30 degrees vs 45) in the thread shape. You could replicate that angle in a normal thread - but maybe that would go against the conventions that people who use screws expect. I.E., the standard that people expect is a particular thread shape, (just like a pan head screw is expected to have a countersink, and a round is not). Whereas the convention for hi-lo screws is the narrower thread angle. People don't expect to have to check the thread angle when they replace a screw.

I do see why you can screw them in more quickly, because it requires fewer turns to screw them in. But perhaps abandoning the self-tapping feature - by having a blunt end - eliminates the time advantage.

*  If you read the reference Bill cited in Reply #6, as well as other references giving details of screw threads, you will note that the thread angle on standard screws is commonly 60 deg, not 45 deg, although 45 deg, as well as other angles, is used.

*  A pan head screw does not have a countersunk portion.  See, e.g., https://fastenerengineering.com/what-are-pan-head-screws/:

"Pan head screws take their name from the appearance of their head, which looks similar to an upside-down frying pan. Pan head screws are a common head type of non-countersunk screw head used in wood screws, self-tapping screws, self-drilling screws, and machine screws."  <<Emphasis added>>

*  In addition to what supersharp wrote in Reply #23, note that a sharp tip is not required for a self-tapping screw.  The sharp tip is required only if you do not drill a pilot hole or if you drill a pilot hole of insufficient depth (i.e., the depth of the pilot hole is less than the length of the body of the screw).  Otherwise, the screw threads take care of the self-tapping function.