bykemike 

I am considering doing some business with a relatively new carbon frame repair business called East Bench Composites. I like their take on carbon frame repairs but, as yet, I can't seem to find enough reviews to help with a decision.

Anyone with information or experience with East Bench?

East Bench Composites

Andrew R Stewart 

I have no experience with them but have been involved with a number of carbon frame repairs over the years as the LBS guy handling the break down and rebuild. So take my comments with some salt...

The first thing I note is their removal of the OEM carbon about the damaged area. I suspect this is to prevent the cracks from spreading/growing, kind of like the "myth" of drilling a hole at the end of a crack in a metal frame. I know of no other outfits that say they do this. The usual repairs I have seen have had a number of wraps of carbon over the damaged areas. These result in a, usually, very minor increase in the size of the repaired area. I wonder if EBC's method is an attempt to not have any build up. If so than do they have the overlapping of the "patch/plug", with the OEM structure, on the inside of the frame?

Next is their use of ultra sound to assess the damage. This seems to me a great method. But I have never done this so don't know if it's more marketing than science.

The claim that they can read the layout schedule of each layer of carbon seems a bit grand IMO. Again, I have never heard of this being done by others before. But if true would be good data to have.

"We use only the correct prepreg carbon fiber" It's my understanding that there are a number of specs that different frame companies use for different frames and for different locations on any one frame. So EBC must have a wide range of materials, carbon row/cloths and resins to duplicate any one repair's OEM spec.

I hope my questions are already taken into account many repairs ago and that EBC is a class act that is using leading edge techniques and will get great looking and long lasting results. I look forward to others with more experience and actual hands on skills replying. Andy

icemilkcoffee 

You need to understand how a carbon fiber frame is made. It is made in a mold, with balloons inside the frame tubes, which are inflated to press the carbon sheets together while it is curing in an oven.
if the repair is not done with pressure or vacuum bagging, it is just a cosmetic repair, regardless of what OEM grade prepreg sheets they are using.

Andrew R Stewart 

Agree that knowing how a frame is made is pretty important to being able to repair one in an appropriate manor. But do know that not all carbon frames, or all parts of one, are done in a mold and with internal bladders for the compression. To not acknowledge the various techniques of manufacturing, to my eyes, indicates a poor understanding of carbon fabrication or a lazy approach to writing. I suspect it's the later.

When I first read this thread I wondered if it would get "better" replies if it had been posted in the framebuilders sub forum. Andy

jccaclimber

I don’t know the outfit and don’t have much experience in composite repair (some in composite manufacturing). That said, what I think is the post-repair picture on their web page doesn’t strike me as the OEM fit and finish.

My only comparison is Calfee, and while there might be slight growth, the repair is otherwise invisible on the Calfee post-repair photos.

bykemike 

Is there a way to get this thread placed into the framebuilders forum?

squirtdad

fyi framebuilders if pretty much steel, with a bit of aluminum

bykemike 

Thanks Dad!

Andrew R Stewart 

And a whole lot more experience at fabricating and interest in alternative methods in general. I agree that most of the topics are metal focused, mostly because that's what most newbies are trying first and the forum reacts to the threads posted. Since the bamboo trend has softened there's been little composites discussion lately. Andy

EBC

Hi Bykemike!

I hope to answer some of the questions in this thread and ultimately clear up any confusion on our processes. In the year and a half we have been in business, we have a PERFECT track record, and have repaired over 200 bikes without a single warranty claim. While our painting process are still evolving, our core competency is structural carbon repair, and in that regard we are quite confident, and we have many 5 star google reviews to prove it!

Reading this thread, I noticed some questions about our process. During our sanding our process, we do read the layup of the carbon as it was initially designed in the frame, and replicate this layup. This technique called SCARF sanding is used in aerospace industry repair to best replicate the strength and stiffness of the original design. Other companies use a single layup for every repair. This method neglects to account for the stiffness that comes from the geometry of the tube being repaired. (for example a chainstay that has a box shaped cross section that is 2"x1" can have a very different layup to a rounded one, and achieve the same stiffness. If the same layup was used for these two repairs, one would be much less stiff than the other, and neither would have the mechanical properties the bike designer intended. This is why we repair the way we do; to ensure proper strength and stiffness.
Additionally, we ensure all of our repairs are completed under the pressure and temperature requirements of the carbon/resin system being used in the repair. Our proprietary methods for doing this do not require us to strip the bike down either, saving time and money.

Please feel free to reach out to us through our website with any other questions you may have!

SIncerely
Jordan Weininger
CTO

squirtdad

your welcome kiddo

bykemike 

Hey Jordan!

I was hoping to hear from you on this forum. I will be in touch on your website, thanks for the response!

bykemike 

I spoke to Jordan @ East Bench Composites a couple of days ago. #1! He answered the phone. This is huge these days I feel. Answered my questions and explained how the repairs go.

Seems like a nice, knowledgeable craftsman type guy. I am keeping an eye on some of his offerings and playing the numbers game on how much I will spend building up a gravel bike from a frame vs.
buying one complete. It is nice to know East Bench is there for the next time I crunch a carbon bike rather than tossing it out.