mstateglfr 

I've seen a couple frames posted here before, please toss up some pics and details about what you built and why.

I've decided to build a steel gravel frame and get a carbon fork(whiskey maybe).
This will something i work on thru 2019 as i need to get more tools.

I'm thinking the overall geometry will match my current Black Mountain gravel bike, but tubing will be a bit thinner(7/5/7 maybe), it'll be lugged, and will be disc brake.
I need to sort out tire clearance geometry and decide if itll be a QR or TA rear dropout(thats a skill fear concern more than anything). Thinking S bend chainstays and need to determine what bottom bracket will allow the most clearance. Also need to decide on OS or XLOS sized tubing. Never ridden XLOS, but I'm 6'5 230, so I'm guessing it would work well and not be overly harsh for my size.

please post up some pics- what do you like about your frame? What do you wish you did differently?
hopefully there are many out there...

dsaul

Why lugs? Lugs are very limiting, especially on this type of frame, where we are trying to fit a large tire and chainring in the same real estate and the angles are going to be different than the traditional road frames that lugs are designed for.

At your size, I would stay away from 7/5/7 tubing unless you ride some really tame gravel. My personal frame(pictured above) has a 34.9mm 9/6/9 down tube and a 31.8mm 8/5/8 top tube and I am 5'7" 165lbs. Although, I do like to ride singletrack trails on my "gravel" bike, so its built more like a mountain bike.

My experience with the previous "gravel" frame and my MTB, led me to go with a long front center and a 50mm stem on this bike. I also set it up with the bars quite a bit higher and closer to me than I would run on my road bike, so the drop position is more comfortable. This has made it much more capable on single track trails, where you must stay in the drops to access the brakes. The long front center pushes the front tire further ahead of you, so you don't feel like you're going to flip over the bars on steeps descents. Basically, it rides much more like a rigid mountain bike. Those changes have had very little negative effect on its road handling characteristics.

I went with Syntace thru axle dropouts on this bike. The Syntace system uses threaded inserts on the drive side that come in 0mm .5mm and 1mm offset eccentrics to correct any dropout misalignment. If the dropouts are aligned, then you can use the 0mm offset. If they are not aligned, you can use one of the offset inserts and rotate it until the alignment is correct. I got lucky and mine doesn't need the eccentric insert.

I have the Whisky No.9 15mm thru axle fork and I've been very happy with it. Plenty of clearance with these 650 x 48 tires.

tangerineowl

No frame-only pics of mine I'm afraid.
Was my first build. Thought it would be nice to have my own tools.
Had to do quite a bit of reading on the subject.
What I did like was researching components; I could have a bike I like the look of and learnt quite a bit about what's available out there.
Did a 1x, but am now putting together a 2x component list.

https://i.redd.it/cvunj0wn2az11.jpg

mstateglfr 

first- really neat build.

As for lugs- i built a road frame last winter with lugs in a class and so its what i know and am confident using. but also, ill silver braze the frame as its what I have access to, so i cant brass fillet braze it together. If I had access to a torch that could lay brass down, i would probably use a mix of lugs and fillet brazing to allow for more flexibility in building. A tapered steerer would be the big difference if I fillet brazed the frame.
But it isnt to be, so lugs are what ill use. The lugset I am leaning towards has a 6degree slanting top tube, but is XLOS tubing. Still not sure if thatll be too stiff for what I want.
My current gravel bike and the road frame I built are both OS tubing and plenty stiff for me when climbing out of the saddle, so Im not sure if I would want even stiffer, especially considering the carbon fork will already be a lot stiffer than Im used to with my steel forks.

Columbus Zona 7/5/7 tubing in OS size is whats on the road frame I built- I figured using it on my gravel bike would be great. If I get XLOS(what your tubes are) sized Zona, the tubes would be about 20% stiffer based on size increase, if I understand correctly. I dont think I would need thicker tubes in XLOS since itd already be 20% stiffer in just the larger form. Ill for sure do more reading on this though.

Do you have a link for the Syntace system? I googled around and found a thru axle, but not a whole system for frame building. Interesting option to allow for misalignment.

As for fork, itd be a Whiskey no7 fork if I go with Whiskey as that is the straight steerer, but a QR dropout. Ritchey WCS fork is the same- straight steerer means QR dropout. Fyxation has their Sparta fork thats a straight steerer and TA, but its something like 750g which is almost the weight of a quality steel road fork. So I may just go QR with the Whiskey or Ritchey. Its a carbon fork- its already going to be quite stiff so no TA isnt a deal breaker by any means.



Question about your frame- why did you choose those cable guides? Ive seen your frame's style and also the common style where you use C shape housing clamps or small zip ties.

mstateglfr 

Is that Ti or steel? Great looking build- whats the writing on the top tube near the seat post?
also, there is a cable stop looking piece on the seat tube in back- whats that?
Lastly, you went with mounting the disc on the seat stay instead of chain stay- any specific reason?

dsaul

You can get the Syntace style dropouts from Paragon Machine Works. There are several to choose from, but they are all hooded dropouts that I wouldn't attempt to use with silver.

I don't like the look of Zip Ties and those C-clips have a tendency to pop off and get lost. I use two different styles of guides. The clipless ones on the hydraulic disc brake line are nice because they don't require cutting the hose to feed it through and they hold the hose quite securely. For shift cable, I use full length cable housing, so they get a double loop braze on guide. I think I got a bag of them from NOVA, but I'm almost out and I don't order much from them any more. I'll have to find a suitable replacement from one of my other suppliers.

What kind of torch do you have that will do silver, but not brass? I use Oxy-propane for all of my brazing.

tangerineowl

Ti frame. The writing is the brands location in lat./long. etched in the frame.

Cable stop/guide for derailleur if fitted (cable from above).

Disc mounts on the seat stay: designers decision.

mstateglfr 

I like the hydraulic guides, nice touch and simple design.

as for brazing- from what ive read, fillet brazing with propane is far from ideal due to the inconsistent flame. I haven't tried though and could definitely practice it if your experience is different.
fillet brazing the top tube and down tube to the head tube would allow for a tapered head tube and would open up more fork options as a result. Definite benefit.
I hadnt planned to use a jig though and am not sure what setup is required for fillet brazing to ensure everything is square. I'll definitely read up on this as if I can learn it and have a way to keep it square its a great option.

dsaul

6 of my first 7 frames were fillet brazed with Oxy-propane, using an oxygen concentrator and a BBQ propane tank for gas supply. It is a bit finicky to get the torch lit, but I haven't had any problems with doing fillets. I've read that the heat from propane is not as focused as acetylene, but I've never used acteylene.

As for fillet brazing without a fixture, I don't think I would attempt that.

mstateglfr 

yup, a big reason in had figured the lugged route is best.
So you just align and tack in the fixture, then fillet with the tube in a vice, correct?
I could look into one of those fiberwood fixtures or making one out of aluminum with internet directions.

Up to now I had planned on using a flat surface and some v blocks, a frame square, etc for getting the frame to be even and square.

but this is months in the future, so there is time to consider other ways.

Thanks for the info so far- its interesting and helpful.

dsaul

Yes, tack in the fixture and then fully braze in a frame stand. You could probably do the necessary fixturing with v-blocks or Paragon Machine Works tube blocks and a flat surface. A tapered head tube would make that difficult. I would go with a 44mm head tube, so you can use any steerer/headset combo you wish.

Cynikal 

I currently have a design on paper (really rattlecad) for a lugged gravel/CX racer. I'm still new at this so I'm sticking with lugs on this one. I'm using a Ritchey WCS carbon disk fork and Paragon dropouts for a disk in the rear. I'm planning on using Spirit for lugs for the front triangle and Zona triple bend 29'er chain stays with curved seat stays. I'm about to start on it and will hopefully have it together before NAHBS descends on Sacramento in March.

mstateglfr 

Sounds like a similar build!
What bottom bracket shell are you going to use, what will your drivetrain be(1x or 2x?) and what size tire are you planning for?

A Ritchey WCS fork would be fantastic and handle the issue of straight headtube for me, but the steerer is only 300mm long and my current steerer is 31.75cm(with same fork geometry as the WCS). So close, but pretty sure itll be too significant a difference. I plan to adjust my current bike to mimick a 300mm steerer and see how it feels over the course of a few weeks on a trainer.

Cynikal 

Not sure on the BB yet, I think most will work as long as it is designed for oval chain stays. Nova Cycles is local to me so I can drive over and look at the bits I need. I'm planning on a 2x drivetrain with clearance for 43mm Bruce Gordon Rock and Roads, basically planning on 50mm on fork and rear stays.

Nessism

Spirit for Lugs is thin stuff. It will make a smooth riding road bike but might be downright soft for the dirt.

Cynikal 

The Spirit tube set for lugs is .75-.45-.75 (which is on-par with Zona) while the standard Spirit is .5-.38-.5. I ride pretty light and weight just under 170 at 5' 10". Do you think I'm being aggressive?

Nessism

Yes, that's a very thin tubeset for an off road bike. Especially given the small diameters, which will lead to flexibility. I'd go to .9/.6 in the same sizes, or move up to XLOS sizes. Realize of course that the butt lengths influence stiffness as well; long butts increase stiffness. The devil's in the details.

Cynikal 

Thanks for the advise. I'll compare the buttings for the different tube sets. I'm currently riding a Lemond Poprad (OX Plat) and have for 12 years without issue.

Nessism

Are you riding it off road? Most likely .8/.5 main tubes with medium length butts.

Cynikal 

Yup, almost all off road. Raced CX on it for a decade (both SS and geared) and weekly gravel rides. In race mode it's under 20 lbs. In the past few years I built up a Some Double Cross Disk for longer gravel rides mostly due to larger tires ( 43mm instead of 40mm's) and a little more upright positioning. The Soma has always felt heavy so I'm hoping to build something in between the two.

Nessism

Hum, you might need to weigh that Lemond frame to help judge tube thickness. Measure tube diameter too although it's likely STD OS sized. Almost certainly it's thicker than Spirit for Lugs.

Cynikal 

I'm sure you are correct. The OEM OX Plat tubes were traditionally thicker from what a custom builder would spec. It's is definitely standard OS and not double OS.

Here are the old recommendations from Henry James for tube sets based on weight. I think what I'm looking at falls in line with this. I know that these are meant for road bikes but I have found little need to go much more robust than these.

fietsbob

Some Italians Built my 2 *Cross Frames.. my DIY frame build was a touring bike..

*Replaced in sequence, not had both, at same time..