Custom cast lugs?
 

Does any one know of or use a reputable casting house that is experienced in casting custom lugs? I know I will have to buy quantity for economy. What are some reasonable price per quantity examples? I just can't find anyone that sells lugs and drop outs that I can modify to meet my designs.

Thanks!

Have you tried contacting Long Shen?

It is not going to happen.

and up front I want to say I am not being defensive or protecting my patch
because there is nothing to protect
so
unless
you are ready to spend $10,000 usd with LongShen for the 3 lug tools to shoot the wax? {lost wax process}
are you able to do 3D SolidWorks Drawings and have the know how of what can be done and not to do with casting small steel parts?
Also costs for Rapid Prototyping $200- $500
then the time doing this will add up to 100 to 200 even 300 hours before you have production castings in your hands
Then there is bound to be alterations to the tools and this costs.
and 3 -6 months will pass during the process
Run numbers can be 300 pieces each lug or part
Shipping costs and taxes and customs fees
yeah the part maybe be a good price, but it is the the above stuff that has to be in the $ maths verses sales numbers.
So think 3- 5years before you get a return on your investment
unless you can sell thousands of them each year.
and also factor in the $ % on the money maths put into the project
The bad news I bring
If it was that easy, every one would be doing it.

more here
http://www.llewellynbikes.com/thegal...mpactanglelugs

If you want to make some patterns for sand boxes and have a small pour done down at the local foundry, yeah, that happens, but these will be big rough castings, {maybe chilled skin}, think model steam locos and machining etc.

The motivation for my casting projects was there was nothing out there to fill my needs and directions, such as compact angles lugs for OS and XL tubes, stem lugs and socket dropouts that are nice and have 2 x M5 eyelets cast in, DT gear bosses etc .
I use them in my daily out out from my bench and also I sell them to other builders.
Direct or via Ceeway.
If I did not sell them, I would not recoup my investment over a 3- 5 year period. {fingers crossed}
and factor in funding stock on the shelf at your shop or your agent

Any questions?

Since cast lugs aren't traditional anyway, :D

You might consider either forming your own out of sheet metal, or welding or brazing them out of tubing (not sure that is traditional either). Another option is to get plain lugs and carve your own design, though that won't help you with unique geometry.

http://bobbrowncycles.blogspot.com/2009/10/tandem.html

This guy had been doing it for 51 years at the time of writing:

http://www.classicrendezvous.com/Ita...tomBiBook.html

So, what does it take to fab a lug? Just fillet braze two tubes for the sizes and angle you want, chop, and carve? Doesn`t sound that complicated to me, but as Silverbraze said about special ordering "If it were that easy, every one would be doing it". I must be missing something, especially after noting how much time it apparently takes an experienced Bob Brown to build a set. Has anybody here done it?

Quite a few builders (Nobilette, Swan, Stoic, etc.) fillet or TIG their lugs (and BB shell, crowns, they can also turn their seatstay caps, cut their drops, etc.). However I guess they are not "true" lugs, in the sense that it would be tricky to bore the socket at the OD of the tube all the way. Or perhaps they file/ream the vent hole open?

There are several ways to make lugs - or what appears to be lugs. One of the most common is called bi-laminate construction. This is where bigger tubes become sleeves that slip over the smaller frame tubes and are fillet brazed together as a unit. Claude Butler in England was famous for making his frames this way right after WWII. My apprentice Herbie is making a frame for NAHBS using this method. <http://www.flickr.com/photos/helmcycles>

The most commonly available tubes that slip instead each other have a wall thickness of .058". In other words a 1.375" OD tube with a wall thickness of .058" will slip nicely over a 1.250" OD head tube. Usually .058" is thicker than desirable so the tube can be turned down in a lathe for optimum looks to about 1mm.

There are 3 bi-lam techniques. 1. The slip tubes can be fillet brazed together to make a lug first. 2. The sleeves can be brazed onto the tubes first and then the tubes can be fillet brazed together. 3. All the pieces can be assembled into a unit and then brazed together at the same time.

Doug Fattic

Thanks, Doug. Boy, that`s a nice looking head tube! Your comments were very interresting, but leave me with more questions.

With .058 wall, in theory you get an avg gap of .0045- just about what they say is wanted for silver brazing. If you were to silver braze the laminations together, then use brass fillets to join it to another tube, would that screw up the silver?
On a related note, I`m working on my first frame now. The .035 tubing I got from Wicks actually seems to measure out at about .002 to .003 thicker, and the .049 seems to run about .001 thick. It doesn`t bother me, but is that normal? I can imagine it causing issues in a situation where diameters or wall thickness is more critical- like your bi-lam projects.

"3. All the pieces can be assembled into a unit and then brazed together at the same time. " You mean the fillet and the lamination all together? Sounds like a real handful to keep good temps on all that at the same time, unless I misunderstand.

Out of curiosity, how did your apprentice go about the HT joints in the pic? Brazed the little "lug halves" for the DT and TT to the "lug" laminate for the HT first and livered it together just like a lug? Brazed the laminates onto their respective tubes, then miter and fillet at the joints?

For a head tube, it seems to me that you could laminate your "lug design" onto it, then turn the outside if ya wanted and ream the whole thing, and finally fillet braze. Would that exra thick tube minimize the heat distortion from the fillet process?

Unless you have a tubing wall measurer, you are unlikely to get perfect wall measurements with calipers, the eror tends to be a few thou on the high side due to burrs or the jaws being high on the inside. Tubing measurers can be easily made, or you can mock one easily enough with a dial indicator and some scrap around the shop. Get a piece of say half in. bar, epoxy a bearing to it in a little dimple, and put the dial over top so it rest on the bearing (heating beariongs can occasionally be surprising, which is why I suggest the above). Mount the bar in a vise, and stick the indicator to the vise jaws. Or any of a million other options. With what calipers cost these days one could also just modify the jaws.

I would brass the lugs together if not welding, and then use silver, that should not be a problem. Due to the reheating braze takes higher heat thing, you can even use similar brazes if you have good heat control. Keep also in mind that OA will weld just like tig. Whatever the arguments against doing that with the frames themselves, there is no reason not to do it with the lugs (of course personal preference still rules).

You don't have to care all that much about heat distortion from the fillet process on the lugs since it won't create deflections in the tube, so long as your final cold finishing and sizing of the lugs gets you where you need to be.

My feeling is there is little reason, and probably some negatives to using 4130 for lugs. Lugs aren't 4130 tubing grade, whatever the alloy. They are either stamped or cast, YUCK :D. Or stainless :eek: Dom tubing should be fine, and would eliminate a range of problems such as hardening present in using 4130. Up here I can't get DOM in the sizes i want it in. But in the US it is all over online. Should make practice cheap. Overall, lugs are overbuilding at it's best anything north of paper, is probably OK. The alternatives are a tiny necklace of super heated cast like steel, a tiny necklace of silver solder, a chunky wrapping of brass. By the time you get to steel lugs, it is all good, again, look at the numbers for stainless let alone cast stainless.

Doug, any info on making stamped lugs in the small shop?

Silverbraze :beer:
I hear all that your saying and I am not going into this without knowledge or costs/investments, time and resources needed for the final product.

I do have 16+ yrs. experience in the metal working industry, cad experience and lots of design history.

One question I do have is where is Longshen based? China, Taiwan or USA? Can you send me a link to their website? Not to assume but one thing I know is I'm not looking for Chinese products. I would like to keep this in the continent.

Why do stamped lugs have such a bad rep.? I am assuming this has to do with the seem?

Has anyone heard of hot/drop forged lugs?

Just throwing out ideas atm...

Thanks for the tips on fabricating the lugs from welded cro-mo tubing but that seems labor intensive comparatively.

As a temporary alternative, can anyone post a link to a supplier of good-high quality lug blanks that I could shape? I am also looking for the socket type dropouts. I already checked Nova and Henryjames and they don't have what I'm looking for.

Thanks everyone for your help.

Cheers!

Both Dazza's and Pacenti's lugs have quite a bit of meat to them for builder shaping.

Ceeway seems to have pretty good photo's of most of what is available out there.

Long Shen is based in Taiwan: http://www.longshen.com.tw/Products_...KindNo=S000385

Stamped lugs do often require more prep work than investment cast lugs but are structurally equivalent. They are also more malleable than cast lugs, meaning you can often bend them to accommodate non-standard angles. Remember, cast lugs were not originally adopted because of superior structural properties, but because they facilitated mass-production of frames. Custom builders were late to adopt the technology.

I had stamped lugs and BBs that required very little work to get the clearances right (as in the tubes slided in out of the box!), but others required hours of prep. Gasp.

Generally stamped lugs have radiussed junctions between the sockets on the inside. This leaves a gap/void that presumably needs to be filled. Cast lugs have very sharp junctions that leave no gaps so they can be used with very fluid low-temp fillers like 55% Cd-free silver. However perhaps 50+ silver would fill stamped lugs? Lower silver fillers? I'll try one of these days and cut it open to check penetration.

Wow, polished stainless lugs would be sweet... what would you braze em with?

I guess if you're welding or brazing together your own lugs, you can do cool stuff like turn in a tapering OD...

That's a beautiful frame... but a couple of things have me quite puzzled... what's the deal with this stuff?

http://farm5.static.flickr.com/4051/...0521a408db.jpg http://farm5.static.flickr.com/4026/...e9fcac5844.jpg

The cable entry on the stem is way trick. But then what happens? How does the cable navigate the sharp corner where stem meets steerer? And then what? Pinch bolt on the upper arm of the calliper, like a freestyle BMX? And what's the go with that slot in the stem above the clamp bolt?

http://farm5.static.flickr.com/4031/...9f21b5b443.jpg

Does that projection below the rack mounts serve a function? It's got me beat.

The front brake cable exits the stem right under the adjuster.
The slot is there to allow the stem clamp to have room to compress and clamp the steerer.
The tube in the back looks to be where the rear brake cable exits the frame.
Lots of cool things happening with that frame- way to go Herbie!

Nifty stuff indeed : )

I can't verbalize this well, because I don't build frames. Dale Saso used to (still does?) make very custom lug angles by slicing two lugs and welding the two usable halves together. He did the slicing with a mill, effictively milling away the unused portion. Talk about a black hole in time management....but it works.

Sounds like almost as much (or even more) work as welding them up from scratch...

I think I've spent 8 hours on a set of chainstay/dropout joins that I could probably have finished in less than 30 minutes, so I take time estimates with a grain of salt. It depends on how much of a perfectionist you are being and how fancy the lugs are. Last year sometime, the guy who started Speedplay had a Masi recreated, and they copied the old Cinelli stamped lugs by tig welding two pieces of tubing together. That's not a real common way of doing things.

If you get .058 wall of the next size up from your tube size, that works perfectly as a lug. Bilaminate "lugs" are made by (usually) silver brazing the lug half on to its respective tube and then fillet brazing the two tubes together.

"Sounds like almost as much (or even more) work as welding them up from scratch..."

Of course one can get the lugs with extra length to them and simple shapes and cut one's own design. So another reason to bother would be to get custom angles. Some additional angle can be bent in, but if one needed more, one could simply cut the inside/outside angle, bend further and re-weld, much faster than making from scratch. One problem with scratch is that to get perfect results one may need to both machine the inside and outside diameters, since the tubing is normally oversize for slip fits, then one has to machine the clearance hole through the tube if one want a real lug where the tubing miters seat and are silver brazed. That is quite a lot of trouble...

Of course a third reason for custom lugs would be oddball tubing sizes and that can't just be tweaked out of existing lugs. I mean something could always be done, but beyond a certain point it has to be easier to start from scratch.

That sounds like what Doug Fattic said above (his "technique #2", last part of post 7 in this thread). What comes across as odd to me was that you silver the laminations together first, then fillet the asembled laminated parts. Bronze fillets, right? I take it that once the silver is sucked into the "lug" gaps and set up it will stay there just fine even when it gets heated to bronze melting point in the next step?

it takes more heat to remelt than it does to melt in the first place. You occasionally get some to reflow, but it doesn't seem to hurt anything.

I'd say it would probably re-melt where you put the fillet. But as long as the silver at the shoreline of the sleeve doesn't melt, the molten silver near the mitre would have nowhere to flow out, and thus it would stay where it is?

The two times I have seen a lug built up, The lug was fillet brazed with a nickel-silver rod. The tubes were then brazed with 56%. Gives enough difference in heat range to avoid affecting the built-up lug

Too bad there aren't any places that make lugs suitable for making an old classic MTN bike frame.