😉, good thing the iphone footage clips at a certain brightness or we’d both be in trouble.

@@CoolBikeProjects arc light on an LCD is simply white light, nothing more. Not brighter as the sun light standing right in front of the actual welding action

yo, are you serious? you're now viewing it from an lcd screen...😅

Agreed! I totally get the need of manufacturers to want frames returned for warranty work, but most of the time we were instructed at the shop to destroy them or throw them away.

@@CoolBikeProjects Yeah, it sucks that parts just get destroyed. Carbon is especially bad for this, as it's just plastic really, and incredibly difficult to find a place that can repair it unless you know an F1 team or something

Quality welders are not that difficult to find. Too many people are unwilling to pay appropriately for the work that is requested. My tig welder does not get turned on until my hourly rate is discussed and minimum is one hour. Many people do not understand that preparation is part of the job and I do my own preparation. Not comfortable having people tell me they have done the preparation.

Great point!

I am learning more and more about the process. As I understand it, the strength loss from welding can come down to a number of factors including the filler material used, the type of tubing (6061) and how quickly the welds cooled. I'll be talking with the welder soon to get more info on it. Thanks for your insight as this is all new to me.

@@CoolBikeProjects i'm glad you're doing these experiments though, perhaps one day there will be some breakthrough that makes aluminum frame repair more accessible to the average biker so that people can have the same ease of mind with alu frames as they do with steel frames

@@daddyshrek2295 7005 frame material get close to this. 5356 filler and will naturally age back close to original strength after 2-3 weeks at room temperature. Artificial ageing in an oven is more consistent, but not absolutely necessary (6h at 90° C, then 4h at 150° C). Sadly, this was a 6061 frame, so now 50+% weaker in the repaired area than it was before the failure. This could have been addressed with some reinforcement and a relocation of the dropper hole to the neutral axis of the tube.

@@danchambers1350I had also opted for a relocation of the hole and mayba adding an inforcement sheet / aluminium part. There was a reason the fram cracked at that spot. Anyway I like the repair effort, as it shows that you can save a cracked aluminium frame.

Thanks Ron!

Awesome!

Good of your dad to try and help .. even if It was a little ugly

You’re not ugly Milton 😂

I once (as a teenager) welded V brake sockets (by myself with a simple stick welder) on an old steel road bike. The brakes were excellent afterwards, unfortunately the fork was weakened after the welding, and broke at 30 km/h +. I flew 5 meters through the air, but wasn't hurt, the bike almost hit me then because it was also flying through the air. Since then I avoided any welding on bike frames ;-)

The shop I picked it up from are pretty sure the guy rode the bike pretty hard. I don’t think it was a quality control issue but who knows?

Do you think broken aluminum drop outs could be saved without heat treatment? Somone has a real nice bike with such a break near me. I could do the welds nonprovlem, but I'm not sure it would just not rip off at the haz after jumping a sidewalk.

@@rolobotoman yes you can, just let it rest for at least 30 days, at least that’s what I do at work and nothing comes back.

​@@velowelder6333 For real?! never eared of letting alu welds rest.. but I only built heavier duty stuff. poor man's heat treatment I guess. I'm really tempted to try! The place it's broken is solid (not hollow), and I think I could beef it up with more material. Thanks! getting advices from people who actually do the thing vs forum nay sayer is invaluable.

@@rolobotoman we used to heat treat repairs but would get warping problems from previous heat treatment “memory” my college instructor and metallurgist is the one who suggested the 30 day annealing time and it has worked for us for over 15 years. I’m not an expert but this is what has worked for me and my company. Btw. I work on 7005 series aluminum using 5356 alloy if that helps. Good luck to you.

Where are you guys based? I have a Mountain Cycle San Andreas with a crack on the main frame around the swing arm pivot weld and running up the side of the monocoque, told its 6061 Solution tempered. Trying to work out best bet at a weld repair, any ideas?

Yes the bend is actually designed that way on many modern hard tails in order to accommodate a larger wheel. It allows for a shorter wheelbase while getting the seat angle correct.

@@CoolBikeProjects You are right 👍🏻 it is in the original design as well, so all should be well, no geometry changes. Fracture not in a location that would cause catastrofic failure if it refractured so thats a good thing. As it is a burly frame it should come out as a good bike for trail riding! I would ride it 😀

Thanks Markus!

Great insight John. The welder commented how thin the metal was, but felt confident the crack would not spread. It should be a good experiment!

@@CoolBikeProjects Hope it works out, but I would keep an eye on the top tube and seat tube junction, and maybe the downtube near the head tube.

Yea, there is a lot of ideas and opinions like that going around to the point it's gospel. I'll take a pro welders word over internet opinions any day. A lot of "cyclists" and "bike mechanics" think they are dealing with cutting edge technology, but they don't realize there is not much out the simpler than a bike , well, maybe a hammer

Yes in the ideal world heat treatment would be nice, but not possible for most of us. No idea on the loss in strength, but obviously a bit stronger than riding it cracked :)

Sorry no connections down in Texas

@@CoolBikeProjects I found someone, thank you.

Will do. That is part of the experiment. Thanks for watching!

Was that follow up video ever made? I have an interest in understanding this outcome and the long term prospects of this repair.

@@CoolBikeProjects how's this 2017 Felt? frame repair experiment going? Can't find the follow-up. Failure is still worth documenting - very good for credibility too.

I hear ya, each of us need to be in charge of our own safety. if you don't feel safe riding it then please don't. My take on this video project was seeing if it was possible to salvage a frame that would have otherwise gone to the trash pile. As many others have pointed out an aluminum frame that has been compromised and then repaired should not be ridden rough. Best wished Paul!

@@CoolBikeProjects so how is the frame holding up? Do you have an update or a video on the situation?

Hi there @pinatabloom, this ended up being a bit of controversial experiment. If you read through the comments there are number of welders and machinists that have chimed in with strong feelings and some sound advice. Most of their comments lean towards the need for heat treatment after welding, which would be nearly impossible for most people due to resources. I felt comfortable doing this as a personal project. I believe the welder did a great job with it, but It is not something I would suggest for most people unless they are wanting to experiment and are okay with the risk of having a frame collapse while riding. Not a pretty picture. I'll leave it at that. Thanks for watching!

Sweet as. 30 day cool off period sounds like the go!

Been saving up for a couple parts to build this back up. I will put out an update video when it is done. Thanks!

I only speak for this project really. I paid the welder $50 for prep and reweld. If I do a single pass powder coat it’s about $100-$125 for the frame to be sandblasted and powder coated.

@@CoolBikeProjects I saw others here in the comments and another bike frame builder channel mention heat treating after a welding. I'm not very familiar with the level of risk or cost to benefit of heat treating in this situation. Is this a consideration you guys are taking into account? Subscribed and hoping to hear an update after the frame has seen some miles put on it. 👍

Sorry Tessa, I took this to a professional welder, and as described in the video, this is purely an experiment. I would suggest you contact someone locally to see if it’s even a viable option for your frame situation.

No follow-up video unfortunately, the cost of getting the bottom bracket replacement hanger and other parts was prohibitive for the project. I finance the projects one bike at a time and couldn’t keep holding up funds for it.

yeah, that would be the proper procedure but it's really costly

6061 requires a multi-stage cycle to restore strength: 30 minutes at 530C. Quench in water or water/glycol. Align within max of 8 hours. Artificial age 8 hours at 175C.) 7005 will naturally age at room temperature close to original temper in 2-3 weeks, but an artificial ageing is preferred for a more consistent result (6h at 90° C, then 4h at 150° C). Sadly this was a 6061 frame...

LOL, you people really believe bike manufacturers do this with their frames? Keep dreaming.

Yes, but I can only speak for this weld project where I saw the work being done.

Hi John, Thanks for chiming in on this. Lots of great comments from welders and metal workers. I have been saving up for some parts to rebuild this bike. As stated in the video I will not be taking this on anything serious and will not be passing this on to anyone else. I think the question of repairing bicycle frames is common because so many have seen videos on rebrazing and repairing older steel frames. Aluminum is something I wanted to dive into because repairs are almost unheard of. I'm guess I'm learning why :)

@@CoolBikeProjects steel is much more versatile. Brazing is much lower temperature than welding and one is not actually melting the steel. Also brazing is carried out at the ends of the tubes which are much thicker than the middle because of the butting/profiling of the internal tube wall. The brazing temperature will soften the steel slightly but will not re-heat-treat it as welding does. Welding thin sections can also introduce horrendous residual stresses due to contraction in the weld itself as it solidifies and cools. Welds need to be stress-relieved and I don’t often see people doing that - especially on KZfaq. I would be very reluctant to repair a carbon frame as well. Once the fibres have been snapped one would need an equivalent thickness of patch to allow the new fibres to bridge the gap and carry the loads. As the resins are thermosets it’s impossible to get a good chemical bond between the old and new resin - the weak link is the resin - Again, I’d just throw the carbon frame away. - I have been doing structural engineering with carbon for the last 20 years and when repaires are needed to carbon reinforced structural parts the design of the patch to bridge the load is quite complex. I know - too much materials science. In summary - you can straighten and braze, even weld steel subject to a few caveats but aluminium and definitely carbon frames should be destroyed & recycled.

@@JohnPilling25 It seems there are carbon repair shops in UK (and probably somewhere else too), GCN made a couple of videos about them. Recently a 787 was hit by lightning and had a hole burned into the carbon fuselage, I'm curious how they repair this since they can't just replace a skin panel like on a conventional aircraft but replacing the segment would mean taking the whole fuselage apart

Repair is complex - airplanes generally replace the entire panel - others use tapered repairs where the area around the hole is ground away very wide and new layers are added, each larger than the previous allowing shear to transfer the load gradually to the original laminate..the patches are cured under vacuum.

@@JohnPilling25 the 787 has no conventional panels riveted on frames and stringers ( unlike the A 350), they use one piece barrels. The whole fuselage is just made of 4 barrels.

Ha ha, sometimes that is the answer although I do hope we made it informative.

Not sure brand welder he was using. I had my brother film this part for me.

Hi Dan, I appreciate the extra insight you given here. Our follow up video will address some of theses issues. Hopefully the disclaimers given throughout the video emphasized the need to have a professional involved and that this is not recommended or endorsed by frame manufacturers.

How did I not find you earlier. I have a cracked intense uzzi. I have had it welded but now I need it heat treated. Do you know anywhere where I could get it heat treated?

@@CoolBikeProjectslooking forward to seeing your follow up video