Berk PROTO-TYPE Composites

[Berk]

Something new in process - handlebar/stem combo.



As you can see there will be used a Zipp handlebar and stem.
If possible I'll also try to make my own stem bonded to a handlebar, should save some weight. Because by bonding the serial stem with the handlebar I won't really save any weight. But it willl add a bit of stiffness and probably "the most important" are the aesthetics. I'll also cover the stem with 3K plain look, because it's for a friend who has my combo with the same beauty look, so it may add a few more grams, but it will look much cleaner and will match the saddle/seatpost combo

Here it is in process - already a bit sanded, and glued together to the right position:



Now I'll remove the faceplate and sand/cut the excess material around the joint, and then continue with the carbon work,..I'll keep you updated!

[BmanX]

Jure, I wish I knew you would do this before I started my stem/bar combo in the US.

[Berk]

I'm sorry to hear that, who in US will make it for you? I just get the chance to make it and finally started with it.

[Werdna]

That is going to be a beautiful combo. Stiff too!

[RyanH]

I'm sorry to hear that, who in US will make it for you? I just get the chance to make it and finally started with it.

Calfee is usually where people get it done in the US.

[hetchins68]

I'm sorry to hear that, who in US will make it for you? I just get the chance to make it and finally started with it.

Calfee is usually where people get it done in the US.

Predator Cycling makes em too

[Berk]

Already some more progress:



...the reinforcements are already laminated, also the "beauty layer" as you can see:



As soon as I make some more progress I'll keep you updated. Tomorrow I have an exam so that's all I managed to do today.. Otherwise I tried to keep the minimalistic look of the joint.

During the work I couldn't resist the idea to get an used bar and make my own stem for it. So I'll most probably try to make it if I found an used carbon bar that fits me. Probably it would be interesting because there could be saved some more weight and still keep great stiffness

[steff]

too strong

[MrIzoard]

Seems like very nice work as always!

//Ulf L.

[1spd]

Lookn good so far!

[plpete]

This is going to look super clean! Great work!

[Elrey]

You know i love this

[dereksmalls]

A fully all from scratch custom Berk bar/stem combo would be killer. Making each part yourself and not anyone elses pieces like your seat combo is the way to go I reckon. Do the whole thing yourself!

[Brandt]

Looks really good Berk! It's obvious to see that you have skills and that you're using professional grade materials. It's a pleasure to follow your projects.

In this case with the stem/handlebar combo, have you made some calculations to guide you in the layup?

[Berk]

@steff, MrIzoard, 1spd, plpete, Elrey

Thanks! Hope you'll like it once I finish it, it will have a gloss finish


@dereksmalls
That would be for sure nice! But it's again a quite specific part (there are different stem lenghts, drop/reach of the bar etc.)..maybe I could make some special moulds where I could adjust at least the lenght of the stem, that would be possible...but for the handlebars I would need to found a compromise.
It's for sure more interesting to start those projects where you can offer something new, and a custom bar/stem combo would be maybe interesting.

At this moment I'm slowly working on some moulds for my first monocoque frame project. The moulds will be made with composite materials, so I'll make them completely by myself. Why? Unfortunately I can't afford metal moulds (too expensive) and just started with my own moulds. Unfortunately I can't yet share any photos, but as soon as I'll be able I'll post them.
Why I mentioned that - I could make the moulds for a bar combo also by myself, so it would make sense to try it. I would prefer to make it monocoque, because the weigth/stiffness ratio would be better. And maybe I'm on that level where I would dare to start a project like this. It's worth to think about it! The only problem would be then what type of handlebar? I would go with 42cm (c-c), I guess it's the most used..And then there is the drop/reach - what would you guys prefer? I know quite a lot of people who like bars like Ritchey Curve etc.,...


@Brandt
Thanks!
Yes I made the calculations for the layup, and it has quite a lot of extra material. I could make it "on the limit", but don't want to (as long as it's not for me ).
If I wrote in %, for example if we say that my combo has 100% reinforcements, then this joint has around 240%. So mention that the combo holds most of your weight, also when you sit on the saddle nose,..but the forces are a bit different here, and there isn't a lot of extra weight if you add 50% if you know what I mean. Otherwise I could make it lighter, the same is also for the combo, but I rather add some more weight to make it really reliable.

Probably an interesting fact - when I only glued the handlebar to the stem, I tried to put it apart. I fixed the stem and hanged with my weigh (almost 70kg) on the bars, and also "jumped" on it and couldn't snap it off. I was really interested to see how strong actually the glue is. So it's very strong also if it's only glued. I use also a glue that is licensed from Boeing for their repairs, and also from our army,...and the Zipp stem is "closed", so there is a flat area around the complete clamping area and the bar is really good bonded with the stem also if it's only glued. But of course after that I made some more carbon reinforcements, and also add a "beauty layer" on the stem. If I wouldn't cover the stem and the area from the joint of the handlebar to the handlebar tape with the "beuaty layer", I could save some more weight, but it's for the aesthetics . If I would keep the UD look I could make it around 7g lighter.