I’ve always assumed it was one of the unwritten rules we’re not supposed to talk about.
Despite what Ed says, I’m in the market the S170 is top of my list and i might have some funds for a frame when our house sale goes through in a few weeks… if my wifenancial advisor gives permission of course.
Wouldn't be surprised if the novelty of bonded frames is a marketing/sales benefit over welding frames... A factor of standing out from the crowd and a...
Wouldn't be surprised if the novelty of bonded frames is a marketing/sales benefit over welding frames... A factor of standing out from the crowd and a possible justification for a higher price (thus possibly a higher margin).
Guys who are tech geniuses aren't always the best marketing guru.
I get why Atherton came out with the alloy/alloy bonded frames. It's on brand. Visual...
Guys who are tech geniuses aren't always the best marketing guru.
I get why Atherton came out with the alloy/alloy bonded frames. It's on brand. Visual & design cues match what people expect from the brand.
Producing a welded bike would be just one more welded bike.
And we've seen Pivot not be able to translate the aesthetic of DW-Link bikes that was so popular with Iron Horse over to their alloy frames. I can't imagine an Atherton buyer getting even slightly stoked by "one more alloy frame".
They'd just put it next to an Ibis or Pivot and pick it apart.
Spot on, for this brand to make a welded frame makes no sense from a brand/marketing lens. The aluminum lug keeps the DNA and the exclusive feel that they started.
it also seems that Atherton is really pushing the S170 as a park, rugged bike you can beat up and it will last. It’s a cool angle because that’s how I feel with my unpainted steel bike. Just throw it in the truck, mash it, no worry for scratch or dent carbon.
Even more so: "The concept of endurance limit was introduced in 1870 by August Wöhler.[15] However, recent research suggests that endurance limits do not exist for metallic materials, that if enough stress cycles are performed, even the smallest stress will eventually produce fatigue failure.[7][16]"
It's the cyclic nature of the loads that mean an aluminium frame will crack sooner or later. It's not a years thing, it's a number of cycles, severity of the loads and the design that dictate when a crack will start forming.
Anyone know what the fatigue life of 7075 is?
I’ve been under the impression that an aluminium frame will have a usable life of 5 years...
Anyone know what the fatigue life of 7075 is?
I’ve been under the impression that an aluminium frame will have a usable life of 5 years before it starts to get “brittle”.
Is 7075 the same/similar in that respect?
Every aluminum frame I've ever owned has cracked, even my scandium Konas. Clearly, in practical applications for mountain bikes, 7075 isn't lighter than traditional welded 6000 series aluminum, so I hope it does have a longer "endurance limit" for mountain bike applications.
Overall ultimate tensile strength is the benefit of 7075 which in turn makes the fatigue limit higher, meaning it will deal with either higher load severity with the same number of cycles or more cycles at the same load severity.
Welding is the biggest liability and point of failure on an Al frame. Avoiding welding removes a factor that relies on human skill and is hard to control, although before the switch to C, Al welding and forming was getting much better, the top end Al frames ~10 years ago or so were pretty nice and it looked like many welds were automated. These days though, Al is made heavy and cheap.
I agree with Primoz about 7075, UTS is much higher, this can definitely be used to increase reliability or cut weight. I don't understand the thought that 7075 doesn't offer some major advantages over 6000 series Al.
IMO, outside of high end automated welding and forming of Al, which nobody does anymore, avoiding a welded Al frame makes a lot more sense to me.
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames...
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
7005 (and some others in 7000-series) is weldable, when welding 7075 is "not recommended" (can't exactly explain why tho'...).
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames...
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere did it. But it might be decades until that is proven to be reliable, or it might never prove to be reliable. I'm not a betting man,but I'd bet on flying cars being available before welded 7075.
So uuuhm, how come noone’s talking about the high-pivot 180mm Lapierre Spicy someone posted 2 pages ago?
It was supposed to be realased last autumn but didn't. And they were on the catalogue before the team ride's it... On another note, I heard that Lapierre and the Accel Group are in financial struggle
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing claims, for mountain biking? The other (in)famous brand using it is Pole, and since their frames are machined Leo can be much more flexible in his shapes and local frame geometry, spreading out stress loads, varying wall thickness, using smarter shapes, avoiding joints that can cause load peaks, etc. But his frames are heavier than traditional aluminum welded frames and they seem to break more. This Atherton frame likely is also heavier than most traditional aluminum frames. What if we returned to the 2009 era and just used thicker aluminum tubing with less hydroforming and more gussets until the weight was comparable?
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing...
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing claims, for mountain biking? The other (in)famous brand using it is Pole, and since their frames are machined Leo can be much more flexible in his shapes and local frame geometry, spreading out stress loads, varying wall thickness, using smarter shapes, avoiding joints that can cause load peaks, etc. But his frames are heavier than traditional aluminum welded frames and they seem to break more. This Atherton frame likely is also heavier than most traditional aluminum frames. What if we returned to the 2009 era and just used thicker aluminum tubing with less hydroforming and more gussets until the weight was comparable?
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere...
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere did it. But it might be decades until that is proven to be reliable, or it might never prove to be reliable. I'm not a betting man,but I'd bet on flying cars being available before welded 7075.
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as it may not fully re-form these crucial precipitates evenly, particularly in the heat-affected zone. This process can compromise the welded area's integrity and strength, making alternatives like bonding or mechanical fastening better for maintaining 7075's high-strength qualities in critical applications.
So its likely possible, eventually, just prohibitively expensive and impractical. When I asked ChatGPT about brazing 7075, it says:
For brazing a 7075 aluminum alloy mountain bike, aluminum-silicon fillers (like 4047) are commonly used, offering a good balance between low melting point and strength. Zinc-aluminum alloys can also be considered for lower-temperature brazing, but they may not match the strength and durability required for biking stresses. Ensure the filler is compatible with 7075 aluminum and the bike's usage conditions, focusing on achieving a joint that withstands the rigors of mountain biking while maintaining frame integrity.
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing...
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing claims, for mountain biking? The other (in)famous brand using it is Pole, and since their frames are machined Leo can be much more flexible in his shapes and local frame geometry, spreading out stress loads, varying wall thickness, using smarter shapes, avoiding joints that can cause load peaks, etc. But his frames are heavier than traditional aluminum welded frames and they seem to break more. This Atherton frame likely is also heavier than most traditional aluminum frames. What if we returned to the 2009 era and just used thicker aluminum tubing with less hydroforming and more gussets until the weight was comparable?
Yes, Nicolai never left the 2000s era of indestructible aluminum frames that didn't worry about weight. I said before I've cracked every aluminum frame I've ever owned, but I never owned a Nicolai haha. Plus they are beautiful.
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere...
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere did it. But it might be decades until that is proven to be reliable, or it might never prove to be reliable. I'm not a betting man,but I'd bet on flying cars being available before welded 7075.
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as...
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as it may not fully re-form these crucial precipitates evenly, particularly in the heat-affected zone. This process can compromise the welded area's integrity and strength, making alternatives like bonding or mechanical fastening better for maintaining 7075's high-strength qualities in critical applications.
So its likely possible, eventually, just prohibitively expensive and impractical. When I asked ChatGPT about brazing 7075, it says:
For brazing a 7075 aluminum alloy mountain bike, aluminum-silicon fillers (like 4047) are commonly used, offering a good balance between low melting point and strength. Zinc-aluminum alloys can also be considered for lower-temperature brazing, but they may not match the strength and durability required for biking stresses. Ensure the filler is compatible with 7075 aluminum and the bike's usage conditions, focusing on achieving a joint that withstands the rigors of mountain biking while maintaining frame integrity.
Oh, chatGPT says! Well then it MUST be true.
Aluminum brazing is already used in low strength, low consequence applications like cable ports on 7xxx alloys. Typically not for main tube joints.
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere...
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere did it. But it might be decades until that is proven to be reliable, or it might never prove to be reliable. I'm not a betting man,but I'd bet on flying cars being available before welded 7075.
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as...
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as it may not fully re-form these crucial precipitates evenly, particularly in the heat-affected zone. This process can compromise the welded area's integrity and strength, making alternatives like bonding or mechanical fastening better for maintaining 7075's high-strength qualities in critical applications.
So its likely possible, eventually, just prohibitively expensive and impractical. When I asked ChatGPT about brazing 7075, it says:
For brazing a 7075 aluminum alloy mountain bike, aluminum-silicon fillers (like 4047) are commonly used, offering a good balance between low melting point and strength. Zinc-aluminum alloys can also be considered for lower-temperature brazing, but they may not match the strength and durability required for biking stresses. Ensure the filler is compatible with 7075 aluminum and the bike's usage conditions, focusing on achieving a joint that withstands the rigors of mountain biking while maintaining frame integrity.
Oh, chatGPT says! Well then it MUST be true.
Aluminum brazing is already used in low strength, low consequence applications like cable ports on 7xxx alloys...
Oh, chatGPT says! Well then it MUST be true.
Aluminum brazing is already used in low strength, low consequence applications like cable ports on 7xxx alloys. Typically not for main tube joints.
Are you making any bikes soon? That Datum looks amazing.
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames...
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
7000 series can absolutely be welded. All of Knolly's bikes are 7000 series and I can confirm they are definitely welded, great piece of kit too
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames...
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
7000 series can absolutely be welded. All of Knolly's bikes are 7000 series and I can confirm they are definitely welded, great piece of kit too
I've only welded with an old Hobart flux core, but Knolly's site says "we use a 6066 series hydroformed aluminum alloy tubing. It's the most advanced weldable tubing alloy available".
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat treatment.
7075 is more than just a little stronger than most Al alloys, typically 525 MPa vs 290 for 6061. So less stress per unit force applied and better fatigue life, especially without the complication and inconsistency of welding.
Like most here I've had a several Al frame failures, always from fatigue at a weld. Bonding is better and more consistent once you have a design and process that works, but that isn't trivial.
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames...
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
7000 series can absolutely be welded. All of Knolly's bikes are 7000 series and I can confirm they are definitely welded, great piece of kit too
7005 (or 7020, the EU equivalent of 7005) can, 7075 for all intents and purposes no. A higher ultimate strength limit will also make it more fatigue resistant. Stiffness wise it's basically no difference between the two.
For brazing you need enough surface area for the two parts to be joined, so you might as well glue the tubes in the lugs and be done with it.
7005 also needs to be heat treated, but it's cooled in air, 6000 series needs to be cooled in oil and thus requires a more complex heat treatment equipment. 6000 is more easily weldable though, so that's a benefit of it.
There will likely be more HP trail bikes for a few years, just like with through headset routing, if it turns out to be a flop, it will take another product cycle to clear then out (4ish years from now).
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat...
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat treatment.
7075 is more than just a little stronger than most Al alloys, typically 525 MPa vs 290 for 6061. So less stress per unit force applied and better fatigue life, especially without the complication and inconsistency of welding.
Like most here I've had a several Al frame failures, always from fatigue at a weld. Bonding is better and more consistent once you have a design and process that works, but that isn't trivial.
7005 is way more expensive than 6061, limited in tube sizes and much more costly when working with billet for machined parts. The advantage is the ease of aging/heat treating.
I’ve always assumed it was one of the unwritten rules we’re not supposed to talk about.
Despite what Ed says, I’m in the market the S170 is top of my list and i might have some funds for a frame when our house sale goes through in a few weeks… if my wifenancial advisor gives permission of course.
Spot on, for this brand to make a welded frame makes no sense from a brand/marketing lens. The aluminum lug keeps the DNA and the exclusive feel that they started.
it also seems that Atherton is really pushing the S170 as a park, rugged bike you can beat up and it will last. It’s a cool angle because that’s how I feel with my unpainted steel bike. Just throw it in the truck, mash it, no worry for scratch or dent carbon.
Anyone know what the fatigue life of 7075 is?
I’ve been under the impression that an aluminium frame will have a usable life of 5 years before it starts to get “brittle”.
Is 7075 the same/similar in that respect?
It is.
https://en.wikipedia.org/wiki/Fatigue_limit
Even more so: "The concept of endurance limit was introduced in 1870 by August Wöhler.[15] However, recent research suggests that endurance limits do not exist for metallic materials, that if enough stress cycles are performed, even the smallest stress will eventually produce fatigue failure.[7][16]"
It's the cyclic nature of the loads that mean an aluminium frame will crack sooner or later. It's not a years thing, it's a number of cycles, severity of the loads and the design that dictate when a crack will start forming.
IIRC one of the main advantages of 7075 over 6061 is improved fatigue life.
I'm not an expert, I'm sure someone more knowledgeable will correct me if I'm off base.
Every aluminum frame I've ever owned has cracked, even my scandium Konas. Clearly, in practical applications for mountain bikes, 7075 isn't lighter than traditional welded 6000 series aluminum, so I hope it does have a longer "endurance limit" for mountain bike applications.
Overall ultimate tensile strength is the benefit of 7075 which in turn makes the fatigue limit higher, meaning it will deal with either higher load severity with the same number of cycles or more cycles at the same load severity.
Welding is the biggest liability and point of failure on an Al frame. Avoiding welding removes a factor that relies on human skill and is hard to control, although before the switch to C, Al welding and forming was getting much better, the top end Al frames ~10 years ago or so were pretty nice and it looked like many welds were automated. These days though, Al is made heavy and cheap.
I agree with Primoz about 7075, UTS is much higher, this can definitely be used to increase reliability or cut weight. I don't understand the thought that 7075 doesn't offer some major advantages over 6000 series Al.
IMO, outside of high end automated welding and forming of Al, which nobody does anymore, avoiding a welded Al frame makes a lot more sense to me.
So, somewhere a couple pages back, someone stated that 7000 seres aluminum can't be welded. But I swear I've had a couple of 7000 series frames and paid a premium for them. GT's I believe? Is it just harder to weld or harder to heat treat?
7005 (and some others in 7000-series) is weldable, when welding 7075 is "not recommended" (can't exactly explain why tho'...).
7075 can't be welded*
6061 and 7005 are the most common for welded frames.
*someone's going to point out the research paper that a lab somewhere did it. But it might be decades until that is proven to be reliable, or it might never prove to be reliable. I'm not a betting man,but I'd bet on flying cars being available before welded 7075.
learnt so much about welding..
i need some mods to a trailer i have.. any takers 
you guys really love welding and brakes..
So uuuhm, how come noone’s talking about the high-pivot 180mm Lapierre Spicy someone posted 2 pages ago?
It was supposed to be realased last autumn but didn't. And they were on the catalogue before the team ride's it... On another note, I heard that Lapierre and the Accel Group are in financial struggle
The Lapidale Spekyll
So the Vital Quorum has decided that 7075 can't be welded. It also probably has better fatigue life. But is it actually better, outside of marketing claims, for mountain biking? The other (in)famous brand using it is Pole, and since their frames are machined Leo can be much more flexible in his shapes and local frame geometry, spreading out stress loads, varying wall thickness, using smarter shapes, avoiding joints that can cause load peaks, etc. But his frames are heavier than traditional aluminum welded frames and they seem to break more. This Atherton frame likely is also heavier than most traditional aluminum frames. What if we returned to the 2009 era and just used thicker aluminum tubing with less hydroforming and more gussets until the weight was comparable?
Ehm, nicolai wants to have a word with you.
ChatGPT says:
Welding 7075 aluminum disrupts its microstructure, dissolving the precipitates that give it strength. Attempting post-weld heat treatment to restore properties is complex, as it may not fully re-form these crucial precipitates evenly, particularly in the heat-affected zone. This process can compromise the welded area's integrity and strength, making alternatives like bonding or mechanical fastening better for maintaining 7075's high-strength qualities in critical applications.
So its likely possible, eventually, just prohibitively expensive and impractical. When I asked ChatGPT about brazing 7075, it says:
For brazing a 7075 aluminum alloy mountain bike, aluminum-silicon fillers (like 4047) are commonly used, offering a good balance between low melting point and strength. Zinc-aluminum alloys can also be considered for lower-temperature brazing, but they may not match the strength and durability required for biking stresses. Ensure the filler is compatible with 7075 aluminum and the bike's usage conditions, focusing on achieving a joint that withstands the rigors of mountain biking while maintaining frame integrity.
Yes, Nicolai never left the 2000s era of indestructible aluminum frames that didn't worry about weight. I said before I've cracked every aluminum frame I've ever owned, but I never owned a Nicolai haha. Plus they are beautiful.
Chirs Canfield / Vampire Bikes' (sometime) upcoming bike with CBF + CF3 + I-Track from the 'gram:
Oh, chatGPT says! Well then it MUST be true
.
Aluminum brazing is already used in low strength, low consequence applications like cable ports on 7xxx alloys. Typically not for main tube joints.
looks like a horst link high pivot (would explain the itrack patent) like the GT or new Norcos
Are you making any bikes soon? That Datum looks amazing.
7000 series can absolutely be welded. All of Knolly's bikes are 7000 series and I can confirm they are definitely welded, great piece of kit too
I've only welded with an old Hobart flux core, but Knolly's site says "we use a 6066 series hydroformed aluminum alloy tubing. It's the most advanced weldable tubing alloy available".
I just received tubes to make a couple of dozen frames. I plan on taking deposits/preorders toward the end of this month.
I think 7005 is a less expensive weldable alloy, as it doesn't need to be heat treated post-weld. 6061 is a better option but needs heat treatment.
7075 is more than just a little stronger than most Al alloys, typically 525 MPa vs 290 for 6061. So less stress per unit force applied and better fatigue life, especially without the complication and inconsistency of welding.
Like most here I've had a several Al frame failures, always from fatigue at a weld. Bonding is better and more consistent once you have a design and process that works, but that isn't trivial.
Hey Primoz!
How many HP bikes is this now, like 32 or something?
Pretty friggin cool!
7005 (or 7020, the EU equivalent of 7005) can, 7075 for all intents and purposes no. A higher ultimate strength limit will also make it more fatigue resistant. Stiffness wise it's basically no difference between the two.
For brazing you need enough surface area for the two parts to be joined, so you might as well glue the tubes in the lugs and be done with it.
7005 also needs to be heat treated, but it's cooled in air, 6000 series needs to be cooled in oil and thus requires a more complex heat treatment equipment. 6000 is more easily weldable though, so that's a benefit of it.
There will likely be more HP trail bikes for a few years, just like with through headset routing, if it turns out to be a flop, it will take another product cycle to clear then out (4ish years from now).
7005 is way more expensive than 6061, limited in tube sizes and much more costly when working with billet for machined parts. The advantage is the ease of aging/heat treating.