rootboy 

Update on the home made brass bar plugs prototype I started in the bar end plug thread. Another one of those projects that may turn out to be a fool's errand. Not very practical. Heavy. And a bit tricky to make to proper size. Cutting the slots in the insertion section turned out to be less than satisfactory as I couldn't really get the wall of the brass thin enough to "flex" when inserted and still be thick enough to accommodate the grooves cut for the O rings.

Based on Iab's cool computer graphics I did spin out a pair of these, with concentric rings cut into the face.



The look pretty neat on the Frejus, giving a bit of a custom touch. Being brass, however, they match nothing else on the bike.
Though they will probably oxidize to a nice patina. Polished aluminum may look better. I have some 1 1/16th aluminum bar stock on the way, just for more fun and games.





I would have taken a light table portrait of the pair but tried the first one in the bars and....ehem ...couldn't get it out! I guess that answers my question about fit.
As it turns out, the outside diameter of the O rings needs to be nearly exactly the same as the inside diameter of the bars. The deflection of the O rings is almost negligible so it needs to be very close. Which will make it nearly impossible to make these a generic fit for many brands of handlebars. Unless I have an exact measurement of the bar diameter.

A fun project. Mostly because I just love the experience of turning brass on a lathe. Soft and forgiving, it turns easily and finishes nicely. The process can be mesmerizing. I've transformed a few short lengths of one inch bar stock into a huge pile of chips.

rotharpunc

I hope you can work something out to make those work, they are very pretty.

due ruote 

Very pretty and nicely crafted, like all your work. I can appreciate the inherent material problems though. I think aluminum might be an improvement. Have you thought about making some with a Velox-like attachment, maybe using a flat head socket bolt for the tightener? They even come in blue; not sure if it's Frejus blue though...few things are.

JPZ66

Wow, those look awesome...though I am not surprised considering the source ! Couple of thoughts/ questions.... If the ID was thin enough, would the material bend or just deflect and remain in tension ? I suppose that might depend on the hardness or treatment of the stock used..... Next, if you did turn the ID thin enough, couldnt you reduce the groove depth and still hold the o-ring ? Is the OD section that fits the tube consistent diameter or is there a slight taper ? I think if that section was tapered, and you moved the o-ring further back as well as made it a single o-ring,, that it might be easier to use, allowing for differences in bar tape, etc. Dunno...just some quick thoughts...... Also, that fact that they are heavier than plastic is not bad...it may help dampen vibration in the bars.

Nice looking pieces RB .....

Joe

spacemanz

I tried to tell you, get the Cinelli plugs. Just $15, & they'll even throw in some free bar tape. But you get an E for Effort, anyways....

Michael Angelo 

Nice work.

gaucho777 

Those look awesome, RB. Very classy way to dress up your bike. I could also imagine some paint fill on the grooves of those plugs.

KonAaron Snake 

Dude - GORGEOUS! RB - you are truly an artist.

rootboy 

Thanks Due Ruote. I did think about the velox type arrangement. Couldn't find the hard rubber stock with a hole bored through it. I even thought of buying a full card of Velox plugs and cutting off the rubber! But, that might be a bit much.

rootboy 

Thanks. Funny you should mention that. I considered world champ color infill, but I'd need more grooves. With 3 grooves I could always do Italian, French, Belgian, German...tri colors, etc.

surreal

These look awesome. In continuing our discussion from the previous thread, I found this crap recently: https://www.mcmaster.com/#rubber-hollow-rods/=p6d8uz I'm thinking the "Extreme-Temperature Silicone Rubber", while more expensive than most options, would probably ave the best characteristics for a plug--- ie, it would compress and get fat, rather than break. 3/4" OD=19.05. 36" length of that, cut into 3/4" lengths per side, would be 70cents per pair, in terms of rubber cost. I'm thinking of getting some to test out the bottle-cap/bolt/serrated washer/nut cheap DIY bar plugs. I'm sure you could machine some awesome endcaps and make something lighter and more easily extracted than what you posted above, but it would look just as hot (or, almost as hot, accounting for the bolt in the center.)

This is, of course, assuming the rubber will be pliable enough....

rootboy 

Thanks Joe. You're a thinking man, I can tell. Brass is inherently not a good candidate for flexing, even if I cut it thin enough. I was afraid of it fracturing. I think this stock is 360 free machining alloy. Not sure. Aluminum might flex a bit better but it can be brittle too. Certainly, they don't have to flex much if I get the OD dialed in correctly. I could make the O rings grooves shallower but I noticed that with a shallow groove the rings tend to roll up out of their grooves when pressure is put on them. I wanted to make the groove depth as close as I could to half the cross section of the rings in order to hold them in place.

Cross section of the piece has no taper. Pure cylinder. Really tough to turn a taper on a short piece held in a 3 jaw chuck. That was the limitation that also kept me from trying the tapered wedge design, like a Cinelli stem, etc.

I thought about a single O ring but figured at least two would hold it in place better. Three might be overkill. Without an expansion plug design the fit has to be so precise though, that it's not conducive to whipping these out for varied applications.

Vibration dampening is an interesting thought. These things must weight close to an ounce a piece, so I ought to have adequate dampening.

RubeRad

Very pretty!

Could you cut slots in the insertion part to allow some more flex?

An entirely different concept, my old falcon has red plastic bar caps that affix with a flathead-screw bolt, and an expansion plug. Could you maybe find off-the-shelf expansion plugs and drill a hole for a good-looking high-end bolt?

EDIT: oopx, looks like I took too long and somebody above gave basically teh same idea. Also I see now you describe both slots and o-ring grooves, but I don't see any slotting in the picture. Maybe 4-6 slots so the remaining insertion brass doesn't have circular strength?

JPZ66

Couple of other thoughts.....usually when inserting something with an o-ring into something else, I apply a touch of lube, so the rubber doesn't grab and roll or tear. Just like when you change oil filter on a car...you should always touch a dab of oil on the o-ring.... The expander style may still be the best way to anchor this securely. I know I would be very very unhappy if a plug fell out while on a ride ! No cheapy screw for that. The hole would have to be drilled and properly counter-sunk, so that a quality flush fitting fastner could be used. And aluminum is probably the better material choice for several reasons...but the brass sure is pretty, and much more exclusive !

Either way, I certainly look forward to and hope you push through the process and eventually come up with a design you are happy with, and that perhaps could be offered for sale. Sadly, I know the labor involved makes any sort of production a challenge, not to mention the effect on price. A program and CNC op would make it feasible though.

Cheers !

tiger1964 

That's really pretty, nice work!

I've always thought that it's a little corner of the bike that could be made to do more work, like storage inside the end of the bar (Flashlight? First aid kit? Birth control?). Hmm, could a teeny clock movement be found to inset in one bar end plug, and perhaps a matching mini thermometer for the other.

rootboy 

Hey Surreal. Good find. I must've not been using proper search criteria as I missed that stuff on MMCarr. Indeed the silicone may be the best of them, despite the red/orange color, as it seems to be the softer material. Not sure what the durometer of the velox rubber is but it seems pretty soft. Much softer than the neoprene they offer at 75A durometer, I would think. And, at 19.05 mm, would probably just work for most bars. Looking at brass socket head cap screws on that site, they aint exactly cheap, but may be workable. Thanks.

rootboy 

Thanks RubeRad. I didn't photo the one I cut slots in as I didn't end up finishing it off. I left the wall thickness perhaps a tad too thick and I wasn't getting any flex from it at all. But I'm sure I could go a little thinner, and make the O rings grooves a bit shallower, and it may just work. I'll probably try that with some aluminum caps, when it arrives. I ordered some 1 1/16 aluminum just to have a slightly larger diameter to work with as my one inch brass rod is slightly too small once I take a skim cut on it to get the whole thing perfectly concentric.

surreal

YVW. My other idea, far cheaper and easier to source, was to use vinyl tubing from the hardware store. I think i'll try that first. It's a shame I gave up drinking beer; some spare caps for test-fitting would be nice right about now.

rootboy 

Thanks Joe. I did lube the O rings before I inserted them. Really needed to on these and let me tell you, these aren't going anywhere. In fact, I'm not sure I can even remove them! Without marring the finish that is. Yes, production time id the challenge, and how it effects a price I would have to charge. These things, as are, take me a long time to make. I'm sure an experienced machinist could whip them out very quickly, but I have to plod. However, with a rubber expander plug one would only have to turn the face plate, as it were.

I might continue to experiment with this in aluminum, but, for now, on to my next whacky project! vvvv

rootboy 

Worth a try I suppose, but I don't think vinyl tubing will have the compressive properties we're looking for. Haven't seen any at the hardware store either with a wall thickness that would work, I don't think. But it might work.

JPZ66

Ok. Listen, if you need a specific durometer hardness and specific size for an insert, I can help a PM me....

As for the leather brake hoods....How Much ?? Any choices in color ? ( although the ones in the photo look great! )

Damn you do such nice work !

Joe

KonAaron Snake 

Both of you do amazing work!

It's a talented group.

Big Block

Have you thought about casting your own urethane plugs?
That way they can be tapered for ease of insertion, and your choice of hardness.
You seem well-equipped for the mold making.
and it is a chance to expand your skill base.

Our local supplier is very helpful. If there is a local supplier near you it might be worth asking, at least for future reference and other possible projects.

I like your latest leather project, and more pleasing to my eye than the style available from Japan with its prominent front seam.
are you wet molding the leather?

gomango

Agreed.

I really like the looks of these.

I would be very interested in some if that's a possibility.

KonAaron Snake 

I'd also be a buyer of the plugs and hoods.