MTB: Cannondale F600 (+/- 9.3kg)

[robobiking]

There's reason why some parts get waisted ( when damaged ) instead of repair. and cranks are on this list. You ask for troubles, other would call it "death wish".

But if you made that decision already BEST epoxy ( non comparable to anything sheer and peel properties ) is Loctite 9394. It's aeronautic glue. BUT : still just glue. You can mix it with small cf particles to increase strength. But it won't increase adhesion ( this is you weak point ( just to big forces for your solution ) .

I agree on your point when I just bounded the 5 broken parts to the crank, but .......... I didn't repaired it like it was. I did it a differant/stronger way. I have riden 250km on them and there are still strong. I did a technical MTB course last week and they worked great.

In the case of the best Epoxy, there are lots of good epoxys. Jure from Berk just pointed me to MMA 2K glue.
THen it was up to me to find a supplier here in the Netherlands who can deliver that.
I let it up to the Dutch supplier which Epoxy he thought was best for the job, and because he is a suplier of Araldite
i went with that.

I shall look into the Loctite glue

[robobiking]

Excellent work. I loved that when the crank failed you posted about it with pictures right away. As you said, very Trial & Error. I make the same mistake when gluing projects too sometimes - where I forget to leave a little room for the adhesive - and instead I clamp it down tight which squeezes out the adhesive and weaken it. So, I was there with you

I used to do a tonne of custom modifications for Honda Ruckus scooters - and all your work on the bars and stem etc etc really brought back good memories!

Thanks, I think that also is helpfull to also put a quote when something didn't workout.
But I'm glad it finally worked out,

Wauw those scooters look very nice, I can see some very nice ideas on those

[stormur]

There's reason why some parts get waisted ( when damaged ) instead of repair. and cranks are on this list. You ask for troubles, other would call it "death wish".

But if you made that decision already BEST epoxy ( non comparable to anything sheer and peel properties ) is Loctite 9394. It's aeronautic glue. BUT : still just glue. You can mix it with small cf particles to increase strength. But it won't increase adhesion ( this is you weak point ( just to big forces for your solution ) .

I agree on your point when I just bounded the 5 broken parts to the crank, but .......... I didn't repaired it like it was. I did it a differant/stronger way. I have riden 250km on them and there are still strong. I did a technical MTB course last week and they worked great.

In the case of the best Epoxy, there are lots of good epoxys. Jure from Berk just pointed me to MMA 2K glue.
THen it was up to me to find a supplier here in the Netherlands who can deliver that.
I let it up to the Dutch supplier which Epoxy he thought was best for the job, and because he is a suplier of Araldite
i went with that.

I shall look into the Loctite glue

For me it's still asking for troubles ,)

If you search for good bonding chemicals look at one place only : aeronautics . If Boeing/ Airbus / Lockheed do not use it... it's not good. Simple as that. Most of this stuff is available for public and comes from well known manufacturers ( loctite, 3m... ) however it's not cheap,and usually for special orders only ( pricey and short shelf life ).

I'm 1 phonecall from 30y of experience with /non&/structural assembling ( ti, alu, cf ) in nautical and aeronautical field, so Berk experience& knowledge is... far behind this to what I have access to, and allow me please to be very skeptical his advices.

[robobiking]

There's reason why some parts get waisted ( when damaged ) instead of repair. and cranks are on this list. You ask for troubles, other would call it "death wish".

But if you made that decision already BEST epoxy ( non comparable to anything sheer and peel properties ) is Loctite 9394. It's aeronautic glue. BUT : still just glue. You can mix it with small cf particles to increase strength. But it won't increase adhesion ( this is you weak point ( just to big forces for your solution ) .

I agree on your point when I just bounded the 5 broken parts to the crank, but .......... I didn't repaired it like it was. I did it a differant/stronger way. I have riden 250km on them and there are still strong. I did a technical MTB course last week and they worked great.

In the case of the best Epoxy, there are lots of good epoxys. Jure from Berk just pointed me to MMA 2K glue.
THen it was up to me to find a supplier here in the Netherlands who can deliver that.
I let it up to the Dutch supplier which Epoxy he thought was best for the job, and because he is a suplier of Araldite
i went with that.

I shall look into the Loctite glue

For me it's still asking for troubles ,)

If you search for good bonding chemicals look at one place only : aeronautics . If Boeing/ Airbus / Lockheed do not use it... it's not good. Simple as that. Most of this stuff is available for public and comes from well known manufacturers ( loctite, 3m... ) however it's not cheap,and usually for special orders only ( pricey and short shelf life ).

I'm 1 phonecall from 30y of experience with /non&/structural assembling ( ti, alu, cf ) in nautical and aeronautical field, so Berk experience& knowledge is... far behind this to what I have access to, and allow me please to be very skeptical his advices.

Thanks for the reply, I understand your point of view.
I understand that from your experience you would not do this.
I hope the crank will hold up.

Ronald