Kitchen Party Build Log

Kitchen · June 22, 2023, 5:30pm

Welcome to the Kitchen Party Build Log!

Intro:

I intend to use this space to share my experiences with bike/component design and fabrication in hopes that some of my successes and failures can be helpful for others. Since I currently do not intend to ever sell any frames I’m going to share all my Fusion 360 and any other applicable files. This will likely include an excess/overshare of information/images, but I just want to put it all out there. During my day job I rarely get to share any of my work, so sharing all these details is a refreshing exercise. If you have any questions please reach out and I'll do my best to answer them.

Plug for day job

The Range: 2021

Link to F360 file

Let’s start with the Kitchen Party Range build. Named after a kitchen range, you know, like a stove. For my first frame I wanted to get the basics down with a relatively straightforward allroad/gravel build. I’m definitely more of a mtb guy and really don’t have a great grasp of bike geo for this category so I loosely based the geo on the specialized diverge. Also I just want to get it out there that I am aware my welds are atrocious. This bike was the first thing I’ve ever welded beyond practice joints so there’s a lot of room for improvement.

Design Goals:

12 x 142 thru-axle compatibility
UDH compatibility
Aggressive amount of water storage
Mounts for a strapless front triangle frame bag
Flat mount for modern hydraulic brakes
Rugged frame so I can huck curbs and fly down sketchy mtb trails
Full internal cable routing
Internal dropper post compatibility
Frame weight is just a mindset

Frame Components Purchased

For the longest time I started all my designs in CAD software and felt like I would get too caught up in the details of sketch constraints and it really hindered any creativity. For this reason I’ve been trying to take the approach of starting all designs with iterative sketches to get the overall design form and all ideas out there. Industrial design is a bit of a passion of mine and an area in which I would like to improve.

To build this frame I had to first build a frame fixture. I chose to base this off the cobra frame fixture V1 and got about 90% through the build before I found his instagram and saw he was working through the V2 and planning to start selling them. For this reason I’m going to leave out any details regarding the fixture build, but will strongly recommend his tooling to anyone in the market. In hindsight, I wish I had just purchased a frame fixture from him as that would have saved me a ton of time, would have resulted in a much nicer product, and in the end building my own wasn’t as cost effective as I had anticipated.

CAD model of the frame build. Take a look at the linked F360 file if you’re interested. I was also happy to see that my modelling process closely resembled what @Daniel_Y put together in his awesome tutorial!

I turned a seat tube collar, aligned it with v-blocks and fusion welded it together.

Serial number engraving on the BB. Number chosen for obvious reasons.

I turned a straight head tube on the lathe and engraved it on the 3-axis cnc mill. This was a bit of a tricky process to figure out to engrave a specified depth on the head tube. I ended up creating a surface tangent to the top of the HT at an offset equal to the tool radius minus the engraving depth. Then used a split surface to map the toolpath to the surface.

Cut and mitered tubes as you’re all familiar with.

Drilled holes for bosses and milled slots for internal cable routing. Slots were milled at 0.25" width and 0.75" center to center distance. Slots were then hand filed at expected angles for internal tubing.

This photo always cracks me up. I can’t not see a surprised fish face. Anyway, internal brass tubing was fit and silver brazed in the top tube. This was brazed with the white flux purchased from framebuilder supply. I used a mapp torch for this process and kept cooking the flux to the point where it would no longer accept any filler. In a later build I found that this brown flux from McMaster Carr was far superior and I had zero issues with it.

Test fitting water bottles to verify boss locations prior to welding.

Some of the miters were halfway decent!

Welding BB junction with aluminum foil argon dam.

Fully welded front triangle.

CNC machined rear dropout plates. First time CNC machining any steel.

UDH adapter plate. Machined using tape and super glue fixturing method. I cannot recommend this method as I’ve violently thrown enough parts across the shop this way. Apparently I didn’t take any photos of the non-drive side adapter plate machining, but it was done in a similar fashion, but in two operations.

Complete UDH dropout assembly!

Machining bending dies for 3/4" tubing out of 1" x 2" x 4" 6061 Al. Plan was to use a similar bending process with an arbor press as seen in Paul Brodie’s legendary YouTube videos.

I apparently didn’t get any good images of the bending process, but here are the three dies required for bending. The center die would be inverted in practice and fixed to the head of the arbor press. Hopefully you get the idea.

Created a 2D drawing with bending distances for reference and drew out a 1:1 scale in-plane bent tube sketch on our 2-axis fabric cutter (pen tool). I bent the tubes until they looked good overlaid on the full scale drawing. Then milled out pockets for tire and chainring clearance.

I cut out three patches from 0.032 4130 plate and engraved the model name “RANGE” on the chainstay clearance patch. These patches were shaped by the Paul Brodie inspired “cardboard aided design” method. Once the patches were welded on, they were ground and sanded down to produce smooth contours.

Creative fixturing to hold the patches in place for tack welding.

Similar method was used to create these contours for the rear dropouts. They didn’t work out as well. They were rushed as I was growing impatient. This lead to poorly fitting slots for the rear dropout plates. This caused an issue when the novice welder was trying to fill a 1/8" gap between 0.25" plate and 0.035"WT tubing…

The clearance plates came out pretty great!, And yes, I definitely overcooked the welds.

Jumping a bit ahead here, but I also brazed in some brass tubing in the seat stays for the rear shifting line. I wasn’t able to insert the bent brass tube into the bent seat stays. I also wasn’t able to bend seat stays with the tubing already inserted. How do people typically do this with bent tubes? I ended up bending the tube, cutting the slots, cutting the drive side seat stay in half, inserting the bent brass tube, welding the tube back together, grinding and sanding the tubing flush with the outer surface. I can’t believe it hasn’t broken yet.

This is another place where I realized I really fucked up. This whole time I had it in my mind that the rear brake cable routing was similar to mtb routing where it would make sense to run down the seat stay. whoops. I was too far in the process to make any changes, but luckily hadn’t inserted the internal tubing on the non-drive side yet.

I shamefully got creative.

Finished welding and test fit in the office.

Head tube

Drive side dropout.

Assembled frame in the machine shop.

Top tube, seat tube, seat stay junction as seen from the non-drive side.

Bottom bracket junction.

I bought a paint tent and suspended the frame and fork from the deck of my friend’s house.

I used paint from spray.bike to paint this frame and I used vinyl stencils I cut out using a Silhouette Cameo 4 vinyl cutter. The vinyl cutter was pretty rad and worked great. The spray.bike paint on the other hand, did not work as anticipated. The process took longer than expected and it got cold and humid into the night so the paint did not adhere very well.

The four-burner pattern peeled off some of the paint.

I ended up removing the initial paint with acetone, bringing the frame back into work and trying again with controlled environmental conditions. I probably should have left it with this paintjob, it looks sick.

Masked off for a third coat of paint. This paint job came out much better, but the paint was very fragile. Overall I am not a big fan of spray.bike’s offerings. I found that loctite would even act as a solvent against the paint.

So I decided to make a custom “ride wrap” coating for the frame using 3M scotchguard clear protective tape. I realize this is probably a bit of a faux pas in the custom frame world, but I knew this paint would get beat to hell the way I ride bikes. I was able to model the wrap patterns with relative ease for all the tubing. The fork gave me some difficulties. I ended up tailoring a piece of kraft paper around the fork, cutting away material until it covered the fork. It came out less than ok, but the rest of the frame looked great. The glossy film really made the previously matte finish frame pop and shine.

Finished frame in the shop.

Finished frame in the fixture.

Showing off the frame fixxxture angle plate.

non-drive side dropout with integrated flat mount.

Drive side dropout

Channeling my inner Kris Henry @44bikes.

Range appliance graphic.

Intext cable routing - Fake BS marketing name for my fucked up internal-external cable routing.

Chainstay clearance patch.

Rear triangle in the frame fixture

Complete bike built up.

Somewhere along the way I also cut out a seat tube clamp.

Really psyched about this supacaz bar tape.

Rear dropout in action.

Dropouts and hub interface from another angle.

I ended up hand painting the head tube logo and it came out terrible. I was so let down after the Engin cycles inspired engraving didn’t pan out after painting. This bothered me for years until I was able to recently redeem myself.

There is a bit of foreshadowing in this image. In January of 2023 I bought a sweet 50W JPT fiber laser engraver and this changed the game a bit. I realized I could possibly engrave head tube badges similar to the etched ones of 44 bikes. The badges shown above are 0.025" 6061 Al. The badges were engraved and cut out with the fiber laser. They were then painted with left over black paint from spray.bike and were sanded to reveal the metal on the outer surfaces. After that they were bent in a 3D printed fixture to wrap around the head tube.

I tried a few head tube badge materials but ended up preferring this 304ss badge with a worn look to it.

Somewhere down the road I also made a frame bag out of materials leftover from one of my previous ventures. Photo taken in Newmarket, NH right outside the old Independent Fabrication mill building.

Thanks for checking out this build and I appreciate you making it this far into the post. Overall the bike rides pretty great and I haven’t had any significant issues with it so far. Since the geo was based off a diverge with a 51mm offset and purchased a whisky fork with a 45mm offset, the trail is a bit excessive and the steering suffers a bit, but not enough for me to complain.

KWebb · June 22, 2023, 5:50pm

I especially like the internal/external routing. Looks like a fun idea and a nice job!
The dropouts also look great👍

Kitchen · June 22, 2023, 5:52pm

Thank you! The routing was definitely a happy little accident.

sikocycles · June 22, 2023, 6:43pm

Sick. Nice work.

Matt · June 23, 2023, 12:01am

Lovely - reading thru it

Something caught my eye, it’s a few years that I am missing from home so I am not 100% sure here but I think my kitchen didn’t looked like that - maybe I remember it wrong? Again, it has been at least 2y since I last visited

Very inspiring, thank you!!

Kitchen · June 23, 2023, 12:10pm

Thanks @sikocycles!

Kitchen · June 23, 2023, 12:21pm

Haha @Matt you caught me, definitely not my kitchen. I’ll have to post a photo of my tiny kitchen workshop at some point.

gschwell · June 23, 2023, 3:05pm

I like your modular dropout solution. Have you noticed any heel clearance issues by pushing the drops further out?

Kitchen · June 23, 2023, 4:57pm

Thanks and good catch. Yes I have some heel clearance issues, but I think they’re mostly related to the chainstay bend placement. The chainstays run practically tangent to the rear dropout plate on the actual bike. I should have placed the bends closer to the rear dropout and created the junction at a larger angle. Luckily I have size 7.5 feet and heel clearance isn’t an issue for me, but some of my friends with larger feet occasionally hit the chainstays when they’re not clipped in.

Seatstays hidden in image on right for clarity.

gschwell · June 23, 2023, 5:08pm

I learned the heal clearance issue on my fat bike, with my heals just barely bumping the seat stays depending on my foot orientation. It never occurred to me to check heal clearance on the seat stays.

Kitchen · June 23, 2023, 5:50pm

Ah dang that’s a bummer, hopefully its only a minor annoyance and not a deal breaker.

Does anyone know of any good metrics or framebuilder standards for measuring heel clearance? I haven’t seen much documentation on the subject and just assume everyone just eyeballs it. I’m envisioning a swept surface concentric with the BB to check for interference based on some input geo. dependent on shoe size, crank length, q-factor, etc. Might have too many variables to define reliably.

Daniel_Y · June 23, 2023, 5:51pm

Wow wow! So much awesome stuff going on to unpack:

Custom engraving
Custom UDH dropouts
Full 3D CAD
Custom bending dies
DIY paint
etc…

Great work! Lots of inspiration here!

Kitchen · June 23, 2023, 6:14pm

Thanks @Daniel_Y I try to do as much of the work as I can and end up learning a few (sometimes difficult) lessons along the way.

Also, I probably should have cleaned up the F360 file before posting it. Things tend to get a bit disorganized towards the end of a project.

Kitchen · June 27, 2023, 4:51pm

Kitchen Party Processor: 2022-2023

Abstract

This time around I cooked up an enduro bike frame and I’m calling this model the Processor, you know, like a food processor. It took about 19 months to design and build from the first rough sketch to the first test ride. I finished the build two weeks ago. It might not be perfect but for my second frame build I’m pretty happy with how it came out. Thank you everyone in this forum for providing me with the inspiration and some concepts that helped me through this project. Ya'll are awesome.

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The frame was made from straight gauge 0.035”WT, 4130 chromoly steel tubing. Both links were machined from aluminum I found tucked away in a drawer in my grandpa’s workshop. He was a bit of an eccentric fabricator so it felt like a fitting use for the material. I machined the pivot mounts and dropouts on the rear triangle from 1018 steel. SendCutSend laser cut the pivot brackets on the front triangle from 0.062" 4130. I machined the idler pulley, oval chainring, bash guard, bearing spacers, and main pivot bolts from 7075 aluminum. The shuttle guard frame protector was made from 60A urethane I cast in a 3d printed mold. I painted the frame and all the components with H and E-series Cerakote and laser engraved the head tube badge and the markings on all the components I made.

The rear suspension is a DW-link style, dual co-rotating link design with a high virtual pivot for a rearward axle path. I mounted an idler pulley to the lower link to redirect the chain forces to provide favorable anti-squat characteristics for a supportive pedaling platform. It’s actually kinda neat - the pulley swings down and back with the linkage to minimize chain growth. And to answer your question, the idler pulley is supposed to look like a shredding disc for a food processor.

This build took a lot out of me and I’m looking forward to taking a break for a while. So far I’ve had about 10 rides on the bike and it super smooth and handles great. The rear suspension is a bit too progressive so I may try to re-make a link down the road. Yes, the oval chainring barely contacted the idler pulley under compression, so I swapped to a round XT 32T chainring and it works fine. I had made a last minute change to the idler pulley placement and didn’t verify clearance prior to cutting the link out. Sometimes you just need to proceed at risk if you want to make any forward progress with a project. Sometimes you make mistakes.

Frame Details

Applicable Files
Fusion 360 file
Linkage file

Design Goals

170mm front travel, 160mm rear travel
High virtual pivot design
Progressive leverage rate for coil shock compatibility
Supportive anti-squat throughout gear range at sag
Manageable anti-rise, ideally around 50% at sag
Simple linkage, supported to shock eyes close to frame to reduce torsion/sideloading the shock
Solid rear triangle for increased torsional stiffness
29/27.5 Mullet/MX wheel sizing
210mm+ dropper post compatibility.
UDH compatibility
12 x 148 compatibility
Easy to work on and maintain
Build mostly from left over tubes from Range build.

Frame Components Purchased

Design

For the overall design I really tried to keep the top tube and seat stays. I tried to keep as many parallel lines as possible and focused on having a clean and aggressive look.

Concept drawing for the Processor with a lot of details to figure out.

Relatively conservative values for 2022. I gave it a high bottom bracket for the chunky New Hampshire riding.

Screenshot from Linkage.

Leverage ratio graph

Axle path graph.

Anti-squat graph for 32-39 gearing.

Anti-rise graph.

Rendering of the completed bike CAD model. It took a while to get the model to this point. V813 in Fusion 360.

Front Triangle

All the tubes prepped to be cut and mitered. Step on seat tube collar was turned to fit main seat tube with a loose slip fit.

BB engraving. Serial number chosen for obvious reasons. The Paragon Machine Works blocks worked great to hold the BB’s!

First tubing cut and already made a mistake. I got too excited and forgot to center the tool. Luckily I was able to file this out to make it even.

TT mitering for DT relief. All of the tubing for this bike was mitered with the Paragon blocks with a similar setup. A digital angle finder was used to set angle relative to vise.

The design for the downtube features a pretty significant bend. I decided to try bending the DT with the arbor press similar to how I bent the 3/4" tubing for the Range build. Here’s and image of machining the 1.5" bending die at a CLR 6.75".

I was trying to get away with using the Paragon blocks to pivot and slide on top of my existing tube bending dies. A liberal amount of copper anti-seize was applied to the bending dies to reduce friction. I knew this sketchy setup was pretty optimistic but had to give it a try. Who knows, what if it works?

It didn’t work.

So after looking through the internet I convinced myself a sand filled tube would work as a supporting mandrel. So I drove to the beach and filled a bucket full of sand, brought it to work, filtered and dried it in our oven, cut the failed tube segment at the bend, welded on an end cap, filled it with sand and welded it shut. I applied some heat to the tube this time and tried to bend it again. It didn’t work. Both of the bends took the exact same shape and they looked like they were making faces and laughing at me for thinking this would actually work. This defeat stole some serious momentum from the project and I had to take a break for a while.

I received several quotes from local shops to have a tube bent for me and even considered having a bent lug 3D printed. I eventually fabricated a bending tool that shares too many similarities with an existing product to feel comfortable showing. This tube was bent to 50.9° over a 9" CLR. If anyone is looking into bending 1.5" x 0.035"WT tubing I can attest to the bending principles of the Cobra Framebuilding TOOB Bender. Joe does an excellent job of designing tools for framebuilders.

Some questionable fixturing methods with 2-3-4 blocks were used to drill holes for the frame protector bosses on the DT.

This brass tube was bent and inserted for fully supported internal cable routing.

Silver brazed the brass tubing and bottle bosses in place.

These bottle bosses cleaned up nice.

For the dropper cable routing I tried to avoid any tight radii bends. For this reason I decided to split the DT and ST routing to run under the rear shock. Since I wasn’t able to bend the DT as much as I needed, I was more limited in dropper cable clearance than anticipated. Some rough mock-ups were performed to check for clearance. This was basically a useless exercise without any of the pivot locations defined so I decided to proceed at risk and figure out a solution down the road if necessary.

Was happy to achieve some decently tight miters!

Front triangle tubes all prepped and ready for welding.

I was about at this stage in the build when I found this forum and all the wonderful tips from users like @ben.land101, @Neuhaus_Metalworks, and many others. The frame was tack welded in the fixture then sequence welded on a table and bike stand over the course of about 4 hours. I still have a lot to learn and improve upon, but overall I am pretty happy with how these welds turned out.

It looks like I put a little too much heat into these joints and probably could have benefitted from longer post flow. I’m manually pulsing and struggle to limit the heating while forming a usable puddle.

Top tube to seat tube joint.

To make this BB-DT-ST gusset I first took a section of 1.375" x 0.035"WT 4130 and mitered it for the ST and BB connections. Then I cut the tube in half with a hacksaw. With this outer segment formed I the two outer plates by the Paul Brodie inspired cardboard aided design (CAD) method.

Outer plates were cut out of 0.032" 4130 with a band saw and ground, sanded and deburred to fit.

I taped the panels on to tack weld them, then removed the tape, cleaned the parts and seam welded them.

The panels were then sanded flush to remove the exterior weld bead. This made the intersections between panels extremely thin and difficult to weld. It took some effort to grind/sand/file these gussets to fit.

Image of inside of gusset.

Welded gusset to frame.

Rinse, lather, and repeat for the seat tube - top tube gusset. It was at this point I noticed very similar looking gussets on @Bucko’s front triangle builds and inquired about welding or not welding the patch on the top facing surface of the top tube. In the end I decided to tig braze it with SiB to close the surface to prevent moisture build up while providing a more flexible interface. I don’t have any direct photos of this interface but it can be seen in some of the later images.

Also, I mitered and welded in this 1/2" tube brace between the TT and DT. Hopefully spaced far enough away from adjacent HAZs to prevent any issues. I’m not sure this offers significant strength benefits and adding it was mostly an aesthetic decision.

I made a 44 bikes inspired pivot locating fixture for the front triangle. I wish I made these standoffs about twice as long to give more space to weld the brackets on the fixture plate side.

Another angle of the pivot alignment fixture

I used a 1-2-3 block to square up the bottom shock supporting brackets. The slots on these brackets were intended to allow torsional compliance in the system to prevent the shock from binding under excessive torsional loading and damaging the shock, but I’m not sure how much that helped. I was originally thinking of going with an eleven-six shock with the spherical shock mount eyes to address this issue.

Shock gusset nut weld
A 5mm thick round M8 nut was turned on the lathe from 1018 steel and welded to the lower shock supporting gussets. A similar clearance hole support was welded to the opposing side gusset.

Front triangle welded with rocker link pivot and shock pivot supporting brackets. Test fitting with shock and rocker link. Lower link pivot mounts not shown yet welded in this image. One mistake I made here was failing to properly account for the tolerance stack in my fixturing. This effectively shifted the entire linkage over 1mm from nominal. This was not ideal, but would still clear the frame.

Originally I had similar ISCG05 tabs cut out by SendCutSent, but the laser hardened the metal and I wasn’t able to tap the M6 threads with the HSS tap so I machined one out of 1/4" 4130 plate leftover from the Range build. I think this part looks pretty rad. If I were to do it again I would just have SCS cut and tap the entire part.

The ISCG tabs were welded to the frame on the non drive side and tig brazed with SiB on the drive side to minimize any potential damage to the threads and BB face.

The pivot mounts were also tig brazed with SiB to the laser cut plates to add strength. Some of the base material melted away on the lower link axial support spacer. Should have gone with a thicker wall thickness on this component.

Rocker Link

For the rocker link I took a lot of inspiration from cascade components and Neko Mullaly’s frame build series. The link I came up with was a simplified version with a focus on ease of manufacturability.

3D printed prototype link.

Section view diagram of how the rocker link is supported, constrained, etc.

Toolpath for the rocker link plates. I machined these two 12mm thick link plates out of 1/2" aluminum with the intent of having finished parts from one setup/operation.

I made a mistake in the toolpath which cost me my trusty back chamfer end mill. I forgot to offset the internal contour finishing pass at an increased axial depth so when the back chamfer mill went to cut after that it essentially tried to slot a 0.025" axial as well as the chamfer on the part. It snapped immediately. $60 facepalm.

I machined a 15mm rocker pivot bolt on the old manual South Bend Heavy 10 lathe. The lathe won’t cut metric threads so I decided to tap them instead. Probably should have gone with a fine pitch but they seem fine.

Highlighting bearing support and offset on pivot bolt.

I accidentally walked the lathe tool into the face of the bolt and it made a ring on the conical surface. I thought it looked cool so I made another. To cut the 5mm hex I purchased a rotary broach, and a sketchy rotary broach holder similar to this one on ebay. I had never broached anything before so I thought this was super cool. Also was very pleased with the fit here!

Photo of the mostly finished link. I did not yet tap the M10 threads for the SS pivot at the time this photo was taken. You can also see the poor surface finish from the back chamfer mill on the opposing link and the spot where it broke.

Lower Link

Apparently I didn’t take many photos of the lower link fabrication. This process was very similar to that of the rocker link fabrication.

These were machined from a single sided, one operation setup. I didn’t break another back chamfer mill this time around.

Machining the first side of the 16T idler pulleys. I decided to machine two at a time. I also use this fixture for my first op on chainrings and bashguards. It locates 6" x 6" plates on three pins and uses the mitee bite low profile knife edge clamps to hold it down. it works really well, but requires a lot of fasteners to hold down parts.

This is my new 2nd of fixture and I’m really proud of the aesthetic. The fixture features an asymmetric locating pin and bolt hole pattern so I can only put the part in the correct way with the holes lining up. This is really helpful for peace of mind while machining.

The plate was drilled and reamed in op1 and provided an excellent fit on the locating pins for op2.

After the bearing bores were cut I clamped the pulley wheels down with washers to finish machining.

I’m too cheap at the moment to buy a custom roundover tool for the teeth so I filed them to my liking.

Finished pulley wheels showing top and bottom surfaces.

Rear Triangle

The rear triangle was designed to minimize torsional compliance. On my current trail bike (Forbidden druid) there is a lot of torsional compliance. This is likely intentional and probably provides more traction, but under aggressive cornering the tire will rub the lower chain guide, so I wanted to feel what its like to ride a very torsionally rigid setup.

I machined the rear dropouts and pivot supports from 1018 steel. For the rear dropouts I drew a lot inspiration from both @WHilgenberg Albatross UDH dropouts and the Zoceli UDH dropouts. One other thing I tried to do with these is include what I’m referring to as frame sliders. These are just 3D printed inserts intended to protect components when I inevitable crash the shit out of this bike. They’re kinda silly, but we’ll see how they hold up over time.

Yet another questionable single sided machining setup. I also machined the rocker link and lower link pivot supports in an identical method, but apparently didn’t get photos of these processes.

Op2 of the non-drive side dropout using 3D printed soft jaws in the vise.

3/4" tube bending setup in the arbor press.

Bent tubes laid up on their 1:1 scale sketch prior to mitering.

These are the rear triangle supports between the rocker link and lower link pivot points. I milled down a 5/8" x 0.035" tube and cut a patch of 4130 to fit with an identical process to what I did on the Range build.

The tubing was sanded down to produce a smooth contour.

Rear triangle in the questionable and quick-and-dirty rear triangle fixture. Fixture was inspired by one I saw in a post by @colinreay.

Duct taped braces for tack welding.

Welded bracing.

3D printed brake mount locating fixture. I was planning on machining a tool out of aluminum but honestly this prototype was good enough for my one-off purposes. I tack welded and did a fit check with the actual wheel, disc, and caliper. There are enough people selling nearly identical products for me to not feel bad about sharing this image. I used a shop made bearing press from a 3D printer lead screw to align the fixture concentric with the rear axle. There was also a boss on the fixture that aligned with the dropout hood.

I clamped a rod between zip tie guides for alignment. These were attached by SiB tig brazing.

Additional Components

I made another 32T oval chainring.

Op1 of chainring finished.

I also made some more seat tube clamps. Op2 shown.

Op3 of the seat tube clamp machined again with 3D printed soft jaws.

Op4 of seat tube clamp. Really wish I had a slitting saw to do this instead. But for now it gets the job done.

some assorted machined components.

I 3D printed a mold and cast a shuttle guard out of 60A urethane. This part actually came out really great, but the urethane is very dangerous and sketchy to work with. I do not recommend using this product. The mold was printed from PLA and coated with mold release. after it cured I trimmed the flashing and punched the bolt holes. The part came out a bit thinner than I liked so I tried to make an additional part when I cast the tummy guard and chainstay guard.

I printed some additional molds for the chainstay protector, tummy guard and thicker shuttly guard. I also sandblasted the molds to try to eliminate the 3D printed surfaces and produce a satin finish. That didn’t pan out so well. I couldn’t find my black dye this time around and was running short on time so I tried to dye the urethane with stamp ink. This ended up being a fatal flaw and the urethane never fully cured and ruined the molds. For future parts I ordered some Smooth-on VytaFlex 60 that is a bit safer to work with. At some point I’ll get around to trying it out and plan to update the build log to share my experiences.

For the head tube badge I had ordered some laser cut letters from send cut send and planned to silver braze them to the head tube. I hammer formed some around an aluminum mandrel and sanded them smooth and they actually looked great.

I shared this image in the Range build, but I purchased a fiber laser and engraved some head tube badges out of aluminum. I painted them post engraving then sanded the outer surfaces and bent them on a 3D printed fixture. I really like that these badges capture the brand, model, and major version number.

Finishing Touches

I don't have any photos of the process, but I sandblasted the front triangle, rear triangle and all components. For this process I used sand I got from the beach and blasted outside as we do not have a sand blasting cabinet. Beach sand should not be used for sandblasting and can cause silicosis. "Do as I say, not as I do." For this reason I was wearing full Tyek PPE with a PAPR helmet to filter the air.

When I sandblasted the front triangle I was pressed for time and gathered some wet beach sand after a storm. I foolishly tried to use this sand as is and soon regretted it. The salty sand oxidized on the frame within minutes. I felt pretty stupid. So I washed the tubes, oven dried the sand and blasted all the surface rust off the frame.

I coated the bike frame with H-series Cerakote, using their recommended HVLP. This coating was a joy to work with after my struggles with spray.bike.

First coating layer was black E-series Cerakote. I partially cured in the oven, then applied the vinyl stencils. I just used regular vinyl for this and not the high temp stuff and it worked totally fine.

Cerakote is pretty nasty stuff. Wearing full tyvek and PAPR with organic vapor filters. Used a HEPA filtered air scrubber to draw air out of the building.

Rear triangle cured in oven.

I’m a huge fan of Cerakote. This stuff is amazing and comparatively affordable. A $35 tester size is enough for an entire frame.

I laser engraved the torque values on all the pivot and shock hardware. Lasers are so fucking cool.

I also laser engraved the idler pulley wheel to look like a shredding disc for a food processor. I mean, its called a shredding disc, I had to do it. I’m not sure if this engraving actually looks like a shredding disc or not, but oh well I tried.

Complete Bike

Not a lot to say here. I took some glamour photos before I took the bike out for a beating.

Lessons Learned

Leverage rate is too progressive - reduce for next build/updates
McMaster urethane is a very nasty material to work with - look into smooth-on vytaflex 60
Don’t use stamp ink to try to dye urethane because you’re in a rush to finish.
Don’t sandblast with wet, salty sand from the beach.
Pay more attention to tolerance stack on pivot locating fixture
Wall thickness on machined rear triangle dropouts and pivot mounts was too thin. I blew through in a couple sections.
Wall thickness on front triangle pivot support spaces was too thin.
Work through head tube gussets/supports prior to welding front triangle.
Tube bending is difficult.
Parametric modelling easy to cause issues with active joints in F360
Verify chainring to idler clearance
Laser cutting hardens the metal - HSS taps couldn’t cut 4130.
Hayes dominion A4 brakes are fucking sick.
Sleep is overrated

sikocycles · June 27, 2023, 5:10pm

That is so sick.

RxDesigns · June 27, 2023, 5:39pm

Great work, so much to take in on this build. Thanks for posting all the details and challenges you had a long the way

Kitchen · June 27, 2023, 6:57pm

Thanks @sikocycles!

Kitchen · June 27, 2023, 6:59pm

Thanks @RxDesigns! I’m happy to share all the details and hope others can learn from my mistakes.

maxwellkeegan · June 27, 2023, 7:55pm

Really impressive build, awesome!

earle.b · June 28, 2023, 1:30am

Great build. Well documented, thanks for sharing.

I agree with your Leverage rate lesson. I’ve learned this on a couple of the frames I built. I went from too little (straight linear) to too much. The plan for the next one is mild progression about 18%.