thousandwords

Hi,

I have an open question for those who would not mind replying- I was wondering what are your favorite tubing family for your gravel builds.Especially for the down tube and head tube, but not only. Something that would not dent that easy, would take some rough terrain well, etc. Weight not as much of a concern.
I prefer Columbus but if you prefer something else I would appreciate any input.
Thanks a lot!

guy153

I usually use Reynolds 631 for everything. But if you want improved dent-resistance you could consider a heat-treated tube like 725 or 853 (and I'm sure Columbus have some too).

thousandwords

Really appreciate it! I know nothing about Reynolds but will look into it for sure! It seems to be many a builder's favorite tubing manufacturer!

Xyphota

Related question, what tubing do most people use for chainstays and seatstays? Do you guys mostly purchase pre-formed, pre-bent stays? And what wall thickness would you use for road vs mtb?

thousandwords

I will chip in with my super beginner two cents when it comes to gravel. It might apply less to mountain.

As far as I can tell the stays are not as much abused as the down tube and head tube so tubing choice is a lot wider. For my first custom frame (a project soon to be started) I bought pre bent stay and my understanding is that that would be desirable.

Those of you with actual real life experience in this stuff- please feel free to contradict me on any of the above, as I do not speak from experience but from randomly acquired third party, unverified knowledge.

Andrew R Stewart 

Headtube- Will you be making the fork? If not what is(are) the fork(s) you are considering steerer specs? Will you want, be able to use, a traditional external cupped headset or Zero Stack/internal one?

Frame- Little is more dent resistant then thicker walled tubing, smaller diameters does help too but not as much as wall thickness. Not that I expect "modern" people to chose tubing specs that are from a past generation...

Stays- I do agree that these see far less dents (chain suck and kick stands excepted). This only reinforces what I said about thicker walls and smaller diameters to a degree.

I don't claim any one brand allegiance. When True Temper was still in the bike tube business I did like them for the wide range of diameter/wall thickness, butt placement choices, USA made and the affordable cost. The differences between similar speced (heat treated and air hardening being different categories IMO) tubes from the current brands are pretty small once brazed up. I would choose based on the specs and not the brand if cost is not an issue (sourcing a couple of tubes from a few suppliers costs more than all the tubes from one source). There are times I have decided on a brand because of other items that supplier offers, just as I have added a few tubes to an order that was motivated by other fittings availability too.

I just finished my first "grovel" bike frame (grovel as a dig at what is a rehashing of a style/use that was common in the 1950s-1970s). All steel, no high end tubing of not huge diameters (28.6 TT, ST and DT) with .9..6 and .8/.5 walls depending on tube. The stays are Deda double curved, but really didn't need to be. Built up with my usual 9x3 system of Campy/Shimano mix, classic Cinelli 64x40 bars, TRP Spyres, and self built wheels (DT parts all) running Panaracer 650Bx42 tubed tires. 24.25 pounds. Pretty close to my road bikes made with similar choice types.

I'll say that even though I've been in the bike industry for decades I have not placed much importance in stiffness or aero aspects and instead focused on what works with little fuss and will make my rides more enjoyable. Andy

thousandwords

Thanks Andy!

Yes I am planning on building the fork myself, in fact it will be the first step in the project, and if it turns out I am not able to do a proper job I will transfer the project to a local willing frame builder. I hope learning curve will be manageable though and I will do a decent job with the fork. For headset I am thinking tapered, integrated.

And yeah, I guess my only general idea for the down tube was thicker walls. something like 0.9/0.6/0.9 or in the vicinity of it. I do like the idea of an oversized down tube (40-44 mm) but you might have changed my preference, it does make sense that smaller diameter does not dent as easy.

I do not care about aero either, but would not mind learning how to account for "compliance"/ride quality when I choose tubing. It's such a vague term though, although apparently is what differentiate a custom made frame (made by an experienced builder that is) from a factory one.

unterhausen

I think Spirit is pretty dent resistant, even though it's pretty thin. I have only used Spirit for lugs, I don't know about the other varieties.
The gravel bike I'm going to start on any day now is going to have a zona main triangle. They have an extended butt version of zona.

thousandwords

Thanks for input, in fact before I started this thread I was thinking zona more than anything else. Zona is not that thin though, I think.

Andrew R Stewart 

"would not mind learning how to account for "compliance"/ride quality when I choose tubing" 1000words

I don't know of any simple formula that results in what the rider thinks is compliant or stiff. But the rider has that final say to what the bike will be labeled as, not the builder. The usual method is to have a standard or understood base line of some other bike(s), and given those specs modify the geometry and tube choices to try to change the total package to what you think the rider is wanting. An engineer type could calculate the torsional or beam stiffness of the raw tubes but once you start to fabricate them into triangulated forms this gets pretty complicated. The opinion that fit and geometry (along with wheels and tires) impact the total feel is one that I have embraced long ago.

So I would ask what bikes (steel and of somewhat similar fit) you have had time on and your thoughts on them as a start. What are you good with in this next bike not doing well? How competitive are you and do you ride with others often?

I'm glad to read that you will try to make your own fork. But I will offer that a tapered (assumed to be a 1.125 upper and 1.25 lower) steerer will be rather stiff. How much do you weigh, what's your max sprint wattage? (This somewhat tongue in cheek). Many/most tube questions are about the frame, not the fork. But I feel that the fork has a large contribution to both the compliancy and stiffness of a bike. more than most will consider. If you really want an uber stiff (and thus less comfy) bike I have a Pego Richie UOS fork kit (blades, steerer and crown) I would sell. My 150 lbs will never need it. Andy

unterhausen

The tubes I'm using are double oversize, .7/.5/.7 There are a lot of variations of Zona though. Spirit is usually .45 in the center. Actually, for your first several bikes, it might not be a good idea. Most people with experience would suggest .9/.6/.9 I think. I have always thought for your first couple of frames, spending more than you have to is just a waste of money. I suggest the cheapest possible tubes, which also tend to be thicker

dsaul

For a first frame, I would use Nova Cycles house brand tubes. I've used their tubes for many frames and never had any problem with them. For gravel frames, I use a 34.9mm 9/6/9 down tube, 31.8 8/5/8 top tube and an external butted seat tube for a 27.2 seat post. I use Paragon 44mm head tubes, because you can run any steerer size by changing the headset and they are thick enough for a beginner to deform them and still ream it back to size.

I use straight walled .035" 4130 tubes for chain and seat stays. I use 3/4" for chain stays and 1/2" for seat stays on gravel frames (MTB frames get 5/8" seat stays). You would be better off using pre bent stays for the first few frames

Trakhak

No one, I believe, directly addressed the OP's saying something about how it's common knowledge that the ride of a frame built by hand by a skilled builder is "obviously" going to be superior to that of a factory built frame, even if both were built with the same geometry, the same tubing, etc.

Coincidentally, there was a Framebuilding thread a while ago where a poster reported proposing that same point of view to a veteran framebuilder. The framebuilder replied, in short, no, that's not necessarily true. A custom builder, he went on to say, can build a frame that is closer to the ideal for a given rider, if that rider's proportions or preferences can't be easily accommodated by an off-the-shelf bike, but there's nothing inherent in hand-building a bike that makes it intrinsically superior. (The guy who had that conversation was astonished by that take and came here to ask for opinions. As I remember, everyone who weighed in here agreed with what the framebuilder had said.)

That said:

Back in the 1980s, Bicycle Guide magazine commissioned the building of seven frames with identical sizes and geometries and with seven different Columbus tube sets and had a number of cyclists ride the bikes (unlabeled except for numbers---bike 1, bike 2, etc.) and then describe their impressions of how the bikes rode. The published results surprised me and, I would guess, most who read the article.

It's a terrific read, but for the impatient, here are a couple of salient details. Toward the end of the article, the writer says, "To be honest, I couldn't tell the difference between an Aelle frame---with straight-gauge tubing and weighing in at 4 pounds 12 ounces---and an EL-OS frame---with double-butted, oversize thin-wall Nivacrom tubing and only 4 pounds of heft." He goes on to say, "If the numbers on the bikes were switched around and I were to test each bike again, my guess is that I'd come up with different tubing preferences. I think my ride preferences were essentially random."

guy153

Here in UK I can only get Reynolds and Columbus and Reynolds is a bit cheaper. But it likely costs more in US. Very find tubes but I don't think significantly better than any quality seamless double butted Cromoly. That's what you're really looking for, from any manufacturer, and for added dent resistance heat treatments may be available.

niknak

I have no allegiance to any tube manufacturer. The hardened tubes from any manufacturer can be drawn thinner. The more basic chromoly will be thicker. You're not going to notice a difference if your DT is from Columbus or Nova or Reynolds if the tube profile is nearly the same.

Since you're a beginner, I'd recommend 9/6/9 top tube and down tube. Choose the diameters based on the frame size, your weight, and power. 28.6 TT is safe for everything but the largest frames and 25.4 is fine for small frames and light riders. 28.6 is my go-to for probably 90% of frames. The DT diameter should be 28.6 for small frames and light riders, 31.8 for medium frames and riders less than maybe 175lbs, and 34.9 if you're big and/or strong.

You don't say how you're constructing the frame. If fillet brazing or TIG then use an externally butted 28.6 ST. If lugs, a 9/6 28.6 tube is standard.

If you're building your own fork, go with a thicker straight HT for 9/8" steerers. No need to make your life harder by using a tapered HT. Buy a fork crown with a built in angle so you don't have to bend the blades. Find blades that have a larger lower diameter made for disc brakes. Use tabbed dropouts and the Willits IS brake mount from Paragon.

Unless you already have experience bending steel tubing, just buy chainstays and seatstays for gravel bikes. All the manufacturers have stuff for that.

Paragon makes a nice low IS mount tabbed dropout.

The biggest challenge will be getting your chainstays the exact same length and the dropouts parallel and in line with each other. With QR bikes, you could file the dropout slots if you were off a bit. With thru axle dropouts, there's no room for error.

Good luck!

Andrew R Stewart 

"No one, I believe, directly addressed the OP's saying something about how it's common knowledge that the ride of a frame built by hand by a skilled builder is "obviously" going to be superior to that of a factory built frame, even if both were built with the same geometry, the same tubing, etc." trakhak

I did try to say much the same but I tend to write like I speak and with the lack of face to face context my attempts can fall below my goals. I was trying to make the point that the rider's fit, the bikes geometry and the rest of the package (the parts) will make a huge difference, independent of the tube choices. Note that the first two are well within the builders contribution. It is common to attribute some characteristics to an element that the rider has been trained (by marketing mostly, and much of social media is just an extension of marketing rehashing what we believe in. Yes, this is a circular and reinforcing system) to believe is the cause of some perceived added value (think cost, fancy paint job or the touch of some guy on a pedestal).

Bicycling mag did another experiments with frames of different brand tubes, but with identical geometry and similar (although some slight difference in a few spots, like blade and stay butts) wall thicknesses. In this attempt the three frames were of different colors (adding that psychological aspect of color influences in our perceptions). Just as with the 7 frame experiment the test riders were unable to determine the tube brands for the frames.

The other frame fabrication article I remember dealt with joining methods. Three typical main frame joints done with lugs and silver, bronze and fillet and TiG welding. They did some lab and work bench testing and all three methods will fail but at differing points from the joint and in differing modes. As TiG was, at that time, just becoming the WAY that it had it's own failure mode was "good" to read IMO. Andy (who can't TiG)

PS- I believe I was one of the members here that posted agreement in the thread that trakhak mentioned.

unterhausen

It's a bit more of a hassle to order Reynolds in the U.S. There is something to be said for personal service from a knowledgeable builder, but it's also nice to be able to point and click and pay with a credit card and be done.

guy153

I buy preformed stays from Reynolds (which are usually "525", i.e. regular chromoly). For seatstays they have three diameters basically which kind of translates into road, touring and MTB. For chainstays I like straight and round/oval/round for a road bike and the pre-bent ones for anything that needs more tyre clearance.

thousandwords

Sorry for not answering sooner, being brand new the forum prevented me from posting more than 5 posts in 24 hours so my replies yesterday were rejected. Will try again now, hopefully the 5 posts a day rule will go away soon.

So much good info above- thank you so much, I really feel I am a lot more confident about tubing choices after reading it all.


Andrew- this would be a gravel bike, and my first such bike for that matter. So using present bikes as comparison basis is not that straightforward. I have several bikes, but for different uses: road, mountain, urban etc, but given drastically different riding parameters, drawing conclusions usable in building this steel gravel won't be that easy. On top of that all my current bikes are made of anything but steel: carbon, aluminum, scandium (with one exception- an old Centurion Turbo which is a steel triathlon/time trial frame) which complicates things even further.

What I am good the project frame/bike not doing well: the most important characteristic would be comfort, with a relaxed geometry to start with. I am minimally interested in such things as power transfer, snappiness, weight and so forth.

I am not competitive, and although I just started racing in the local amateur cyclocross league at the end of the season last year, this new project will not be used for any racing or competitive riding, just leisure rides, most of them by myself.

I took your straight head tube advice to heart and chucked the tapered idea for good- thank you!

I weigh about 200 lb but this will change soon once this winter is over and I can get active again. My ideal weight is about 180 lb and I should be back there at some point this year and stay there. I have no clue about peak wattage, never had a power meter, but although I am decently fit, I do not expect this frame to be abused much at all.

Lastly, even though it does not sound like it might be the ideal choice for this build, my interest got piqued on that Pego Richie fork kit, and would love to learn more about it. Would you mind sending me a bit more info on it through means of a private message? Thank you!

thousandwords

Exactly my thoughts on it too- was planning on thick tubes especially down and head, even to the point of "overbuilt" kind of thick. The reason I was thinking Zona is because I saw a Zona 1/.5/.8 down tube on framebuildersupply that I thought was a decent choice. Tried to post a link here but again it won't let me because I need a minimum of 10 posts before I can include links.

thousandwords

That is exactly the type of info my inexperienced self finds invaluable- I could not thank you enough! I will look into Nova tubing, and even if I will pick a different manufacturer like Columbus or Reynolds, the wall thicknesses will most definitely be informed by the type of info experienced builders like you kindly offer as in above.

For dropouts I have already decided for Paragon and in fact purchased one of their polydrops.

Another contributor already mentioned I should probably use a straight head tube, and your 44 mm suggestion cements it- I feel like it's the way to go and I will probably be ordering one soon.

Lastly, plan is for pre bent stays, no matter what thickness I decide for.

thousandwords

That is a terrific read indeed! And at least for me, an eye opener at that! I might actually revisit this after chewing on it for a while and allowing it to settle, cause it actually goes against my prejudices in regards to a custom made frame.

thousandwords

Thanks for all of that- as I was saying in one of my previous posts, this is the kind of stuff that would help me the most for now- actual specs I could use for starting points in my search.

I was planning on a mix of TIG and fillet brazing but details might change as the project takes shape. I initially ruled out lugs (which would be the easiest for a beginner like me) because I thought my choice of tube sizes would prevent me to use lugs (I like the idea of an oversized down tube) but seeing the recommendations in the posts like yours and others above I am reconsidering that.

Yeah, earlier posts already convinced me to chuck the tapered head tube idea...and angled crown idea was already creeping in, saw a 7 degree crown on framebuildersupply that I kind of liked and they have the straight blades that would fit it.

No experience with bending tubes so pre bent stays it is!

Planning on using a Campagnolo Ekar groupset for the build, it comes with flat mount calipers, so the dropouts will have to be flat mount. I bought a paragon polydrop set which I will most likely try to use. Unfortunately Ekar asks for 12 mm TA so yes I am really afraid of the alignment issues you are mentioning. But there is a learning curve for everything...

Andrew R Stewart 

1000words- Where are you? Some of us here are willing to help out beginners with hands on stuff. Andy

georges1

I prefer Reynolds 631/853 and Dedacciai DR Zero/DR Zero Uno. Columbus as much as it is good is some what overrated especially with some of their series who weren't that light sl,slx,brain,thron, tsx or those prone to failure like the genius, cyber or to be prone to rust like the el os,max,min max and over max. The best series from columbus are the Air, gilco design used by colnago, neuron, nemo, foco, ultra foco, spirit, xcr, hyperion (columbus proprietary titanium 3AL 2.5V), altec, altec2 and starship. Excell made also good tubes but rarely seen on bikes,those were often used by French frame builder Jean Marie Pilorget