Thanks for uploading. Fascinating the steps that bike manufacturers skip to prepare a frame. Just that small detail of the bonding agent could prevent a heap of trouble
''in the factory they don't do it'' This is true, I've had two very expensive Cervelo frames ruined by them not doing this very simple process. Luckily both were warrantied on other matters, but they did not consider the degrading of the frame through this corrosion a significant matter although it ruins your frame aesthetically and mechanically. I can't believe I paid top money for such shoddy manufacturing. I sold both new frames on and purchased well made bikes frames instead. You know what Cervelo told me to do....''Put some vaselline over the corrosion and delamination '' !
I've often thought, Raoul could start a franchise for repairing carbon frames. If I was in need of a carbon repair I wouldn't feel confident with anyone else doing it.
Hi Raul - Thank you so much for producing an excellent series of videos. Why is it so ridiculously common to see the use of stainless bottle mount bolts which offer unneeded high torque up and release setting ? Also why is it that little if ever use is made of thread sealants on bicycles and not thread locking compounds as thread sealants perform much better than greases. Greases are easily removed by detergents - High pressure water jet cleaning - Corrosion - Atmospheric contaminants and variances inTemperature conditions. THREAD SEALANTS can offer a variety of superior performances over greases - Typically : Reduce galvanic corrosion in dissimilar parent metals - Provide Complete insulation from Atmospheric conditions - Offer specific torque up and release settings relevant to material requirements and assist in keeping cohesive integrity and longevity of materials and sealant.
I had this frame in the same colour ways. Sold it to get a disc bike with wider tyre clearance. Kinda wish I hadn’t. This was my favourite bike I’ve ever owned
What's the point of using epoxy? you can't insulate it from behind and the way the rivnut works is to mechanically crimp so you won't get any insulation from it. Unless I've missed something.
The alodine is an anti-corrosive coating for the aluminum. It works similar to anodizing. The epoxy does help, when the rivnut is pulled and the inside mushrooms out, the adhesive oozes out with it and incapsulates the “mushroom” tip. You only need a few thou of adhesive to provide isolation. Finally, it seals the installation so that no electrolyte can get there. If you wanted to have an alternative you could go with duralac for permanently/semi permanent fasteners or lanocote for temporary/serviceable assemblies.
I could be wrong but where does the Galvanic Corrosion circuit come from?? You have a Carbon Frame - Neutral & some Aluminium Rivnuts : -ve Are the rivnuts just not corroding due to the salty sweat and leaking water bottles sitting on top of the rivnuts causing them to corrode?? There is nothing on the bikes where an electrical circuit is being set up to cause the electrolyte solution to create some very small electron wizardry. If this is the case then Stainless or another higher resistant corroding metal should be used. Either way, I still enjoyed your video :)
Exactly. I also in doubts if metall pkus carbon may corrode with water or some. Carbon is neutral. Metall may coorode or two different metals may corrode together as galvanic pair while both stay in water. Probably this happen as pair with bolts. Moreover just aluminium alone in water or weak acid takes protections film of its oxide and will not corrode further. I am not chemic but root cause here is the question.
aluminum and carbon is litterally the worst-case for galvanic corrosion. Ti and carbon has essentially zero galvanic issues. 316 ss is also a great option.
I had an old Trek 8900 frame that epoxied threaded external posts to the carbon tubes instead of drilling them so you'd use nuts instead of bolts to affix the water bottle. No compromising tube strength, no galvanic corrosion. Superior design by far.
Interesting video. Thanks. What are your thoughts about leaving press fit by some manufacturers? That means more aluminium is the frame with the risk of corrosion??
Hi, I have a problem on a CUBE MTB. The Bearing of the chainstay has play, in an aluminium frame Iwould go ahead an glue it in with Loctite 648. Can I use the same method on a Carbon frame?
Outstanding content! Thanks a lot for sharing. I have a question, I want to drill new holes on the lower tube for a bottle cage, I know I will be cutting some of the carbon threads, but isn't it like the manufacturers do? It seems like they mold the frames and then drill those holes, isn't it?
Is it not somewhat counterproductive to bond the rivnuts in? The bonding could make it difficult to replace the rivnut the next time. Depending on the strength of the adhesive and the thickness of the bead you might be forced to use excessive force to remove it and risk delamination. Even if the insert is less likely to fail due to corrosion, it still might need replacing - due to stripped thread for instance. I almost stripped the threads on one of my bottle cage inserts (I presume they were overstressed during installation, I felt them starting to go and left off immediately). I was thinking about replacing them, first passivating the rivnut in some way (oxidising with some kind of acid) and using something like silicone sealant to prevent ingress into the interface. Also, painting the rivnut before installing could provide some insulation from carbon. In other words, you've shown us how to replace inserts the correct way, but it would be useful if you showed us how to do it the half-decent way, for people who don't have access to airspace-grade compounds and sealants, and specialist tools like rivnut pliers. For instance, one could use a bolt and nut of appropriate dimensions to pull on the threads of the rivnut and so tighten it.
If you do no have the correct tools don't do the job, get someone who does to do it for you. Unless you are in the middle of nowhere. Don't paint the rivnut either, as soon as it is compressed into place the paint will crack and flake off.
@@Rover200Power Sure, having proper tooling is the best option, but not having the "correct" tool has never stopped me doing the job, in case I have a reasonable expectation to do it well. For me, any kind of tool - bought or improvised - IS the correct tool if it does the job. Apropos of painting: I would have used an acrylic paint, which is quite ductile, at least until fully hardened. If it cracks, it will crack mostly in the area that is not in contact with exposed carbon fibres. Of course, it can't be guaranteed that it would protect the insert from corrosion, but it's worth a shot. Especially when you consider that the rivnuts are installed without any type of passivation or separation in the factory. One other option would be putting some thin electronic heat-shrink tubing over it before installing, but that may prove to be too thick to fit. At any rate, I find thinking about solutions to technical problems much more intellectually rewarding than simply having "pay an expert to do it properly" as an answer to everything. I like thinking about this stuff, fixing (and sometimes breaking) it.
horrovac, necessity is the mother of invention and you are on the right track. Even bike mechanics will never have the “correct” tool for all circumstances and will improvise. www.junoindustries.eu/en/products/range/rivet-nut/rubber-rivet-nut-from-specialinsert-type-rubber-nut.html www.junoindustries.eu/media/productpdf/275/rubber_nut_rev01en.pdf
Sometimes you have to improvise and I also enjoy a tech challenge, however the correct tool makes a repetitive job much easier. Paint and heat shrink are less than ideal when epoxy adhesive is readily available.
Luescher Teknik how come you dont anodize the AL inserts sd well as the obvios bonding needed? I thot that prevents the interface corrosion in general and additionally it would stop the exposed AL from oxidizing.
Is alodine more or less protective than anodising the inserts (alodine is difficult & expensive to get in the uk, & environmentally horrible). Any opinion on just using a stainless steel rivnut rather than aluminium?
Nice job but instead of problematic aluminum, I would use a strong plastic insert- if I used an insert at all (I would not.) That 0.001 layer of adhesive will wear off in about a week. Instead, I would simply use a CF wrap method e.g., use carbon fiber to wrap e.g., a flat plastic or CF bracket. This can hold the bottle holder onto the frame. It would spread the forces out better and be safer overall. If anything, it will make that section of the frame stronger. Anytime you drill, shock or introduce aluminum into a CF frame, you are making it structurally weaker.
Hi, thanks for the video 👍 I watched this as, after much deliberation, I think I’m going to install 3 rivet nuts in my Kinesis ATR V1 carbon fork to carry more water. I’ve come to the view that the 3 holes will be in the neutral axis of the fork so shouldn’t impact strength and if properly bonded as you show should be ok. But….. thought I would reach out for an opinion from a carbon expert before I make a daft move. Do you think doing this would be insane, moderately sensible or absolutely fine….. if done with care? Thanks for any thoughts, I know it’s a bit of a difficult question to answer.
Great video, thanks for sharing. I’m about to do similar to relocate a FD hanger lower on my seat tube. Can only find Aluprep and Alodine in huge quantities in Australia. Any ideas where I can get my hands on a thimbleful?
Great vid Raul! When installing new rivnuts after drilling new holes in a carbon tube, does there need to be any carbon reinforcement added to the surrounding area prior to installing the rivnuts with epoxy?
This is not a DIY effort. Don't try this at home kids. BTW, wouldn't Ti inserts last indefinitely? Is there anything we can do to minimize the corrosion and prolong the life of the factory inserts?
Yeah, use the same material for the frame as for the inserts ;-) My aluminium frame has a claimed weight of just under 1kg. I don't know why I should buy a carbon frame with a similar claimed weight or 100 to 200g less, while it costs way more money I can invest in some other lighter parts on the bike.
Can't understand that manufacturers who sale us carbon frames at very high prices saying that it's partially because it's labor intensive and they skip an operation that would cost them almost nothing and would add less than a minute of processing in a manufacturing environment. But then again, I'm not surprised by anything in an industry (not the only one) where accountants are responsible of final manufacturing decisions.
No accountant I know would risk potential reputational damage and resultant loss in revenue. It all comes back to the people who run these companies deciding that, as long as they make their money, they can live with compromised R&D and QA.
@@pam00088 Yeah. In this world, we all know accountants are the most honest people. The fact that you don't know a dishonest accountant is irrelevant. It's anecdotal evidence. I don't know accountant that is gay. Yet they exist !
Sylvain Michaud My bad. I totally didn’t realise that you have insider knowledge. Weird coincidence that bike companies with poor quality control are all owned by dishonest accountants though.
@@pam00088 Owners are the share holders in most cases. Decision are made by those nominared as CEO, CFO, ... These people need accomplices to operate in a way that generate bad products. Engineering, Accounting, Marketing, ... are involved. But in most cases, specialized accountant will make recommendation in order to reduce production costs and maximize profits against the engineers recommendations. Just like marketing will pressure for earlier production before engineers would recommend for safe and reliable products. And yes, I have been involved as a product manager (not in cycling). Most of the time, products are bring to market, to early in their development cycle with really stupid manufacturing choices made along the way. People that are in denial are generally the ones benefitting of the system or those that have a vision of the world that would collapse and prefer to be blind to reality and generally have a tendency to be right wing.
this happened to a mounting point on my carbon fork recently. a ton of white dust, almost sand like, accumulated then the insert just dislodged. my question is: is the fork still safe to ride? does it damage the carbon layup when the insert corrodes so much?
Hi Raoul, great video! I was just wondering why they use Aluminium Rivnuts instead of Stainless steel? Would Stainless be the better option for a replacement?
If you don't have a rivnut tool or want more robust threaded inserts, you can buy stainless M6 Tee nuts, cut the teeth off, scuff them with the rotary tool, bond them in the hole with JBweld, flat side up, and press a couple layers of CF over the top to really lock them in place. Take care and it'll even look nice.
Hi. Love the video series and helpful content. May I ask what would your choice be regarding replacing bottle cage mounts on a 6031 alloy frame. Which would you use - Alloy or 304 Austenitic Stainless steel Rivnuts ? Many thanks and happy pedalling 🙏
@@LuescherTeknik Thanks for your message Raul. There was evident galvanic corrosion between the original alloy rivnut and bottom frame tube when I removed the original rivnuts. Bare in mind this bike is only 3 years old and the original rivnuts had been sprayed with clear coat which sealed them from exterior contamination. but it didn't stop interior deterioration. Many bikes are now coming on the market with no paint job at all - Just a brushed alloy finish a couple of transfers and a spray of clear coat - This saves companies millions of dollars in time - materials and labour. Sorry I got side tracked. I removed both 5mm bottle mounts and replaced them with 6mm alloy rivnuts. I agree I would also use the two preparations but I was unwilling to pay $200 for the two bottles of prep fluids. I have simply cleaned & sterilised the Alloy rivnuts and applied epoxy to the mating surfaces - I'll be keeping an eye on them too as I know you can easily get Galvanic action from two mating components machined from the same billet. Best wishes and happy pedalling 🙏
@@LuescherTeknik Hi Raoul. I have since been able to find smaller amounts of bottled Alodine & Alumiprep in Australia which makes the whole process financially friendly - Under $80 ! Many thanks for your help and best wishes Raoul 🙏
Please cut up one of these older isaac frames, that company from the netherlands, id like to see one of their frames from the inside. I wanna know if ive been riding something thats a potential threat to me haha
I've been told by my bike store and Ridley that its up to me to do this for a stripped out rackmount after 1 year of use! So I'm hoping to do this right since my mount is inline in the seatstay so there is mm's for room for error. Was wondering where I could source good quality rivnuts online? and typical sizing?
Typical sizing is M5. They are available in almost every hardware store. Nothing special is required. Just avoid the zink coated ones. For the bling you can go straight for stainless.
No. Grease on the bolt threads would coat (and likely protect) the inner bore of the insert (the area that comes in contact with the bolt), but this would do nothing for the outer surface of the insert that comes into contact with the frame material.
Why? If they find people rich/dumb enough to buy these why should the refrain from saving a few pennies and make a few more pennies more or invest them into marketing bs? ,-)
Raoul what is your technique for dealing with rivnuts that are loose in their socket and therefore can't be drilled out? Have encountered this several times over the years, usually when the bottle cage bolt is corrodded and the force needed to remove it exceeds the strength of the rivnut/socket bond. Seems a bit of anti sieze or grease on the bolt thread during assembly would help avoid this issue.
Yes this can be a problem, I have a range of methods and have always managed to get them out, usually by careful drilling. Prevention is always better than the cure in this case.
Anodizing is a good idea and would help with the outside portion, but I suspect the surface would crack when the rivnut is compressed. So part of what the adhesive helps with.
@@LuescherTeknik Understood, but it would make a much better product with minimal cost and effort. Sealing with adhesive when put in would solve this problem ( for ever? ) Rgr
Вообще неизвестно. По хорошему должны быть нержавеющие втулки и точно такие же болты из аналогичного материала. Тогда не будет гальванической пары и если эта нержавейка выдерживает воду или соленую воду -. тогда не с чего ржаветь
Would this “rubber isolation brass threaded insert” offer a possible longterm solution; www.junoindustries.eu/en/products/range/rivet-nut/rubber-rivet-nut-from-specialinsert-type-rubber-nut.html www.junoindustries.eu/media/productpdf/275/rubber_nut_rev01en.pdf May require slightly enlarging the frame hole 8tenths of a mm to accept the insert, however it requires no special tool to install.
rkan2, I believe the same could be done as others have suggested using heat shrink tubing on an aluminum rivnut prior to installation. May still require enlarging the hole .5-.8mm. I think I will go clean the sweat off my bike now since this topic is a good reminder to not neglect the minor things that can become problematic later on. 🤨
Luescher Teknik, the 2nd link is the technical document and assembly states deformation upon tightening, so they should tighten permanently. The subject matter was a great reminder of not ignoring the small hidden details of regular cleaning. With the heat and humidity I ride in, I rain sweat all over the top and downtube.
