So I figured I would wait until after completed to post anything about this, mostly because I have found limited threads about building FS bikes; and a good portion of the ones I can find don't seem to have an inspiring following. I will also preface with this being my first FS build I was not looking to build something amazing, but rather to see if I could do it and start to learn the process. I figured I would post what I did at least if that is somehow helpful to anyone else, and I welcome whatever comments you may have as I generally learn quite a bit through them.
The frame is 150mm, progressive rate, single pivot with a rocker mounted to the top tube and intended for a 160mm fork. I am not the best frame builder nor would I say I have an amazing grasp of bike geometry so I will be brief with this part, but the high level summary is illustrated in the below CAD + LinkageX3 screen shots:
After talking to a buddy of mine who has built many full suspension bikes, I settled on the tubing / steel selection as shown below. I was advised to use a minimum of 0.058" tubing (if not 0.065") anywhere that I pierced a pivot point, and 0.035" straight gauge anywhere I was going to tie in the shock mount.
For bearings, I chose to stick with Enduro MAX bearings because they have a reasonable selection of sizes, are specifically intended for bicycle frames, can be found easily/cheaply, and have higher static loads than typical radial bearings. I used a single bearing at each side of every pivot, with the exception of the main pivot, where I stacked two on each side.
Physically incorporating the bearings into the steel parts of the frame, and being able to jig things properly, in my mind was going to be one of the hardest things to figure out how to do. I opted to experiment with this first before purchasing any tubes/parts/etc. to make sure I had a feasible plan... In the end, what I ended up doing was purchasing 17-4 bar-stock in necessary sizes that I would turn into bearing housings. I started by cutting to length, pre-drilling a smaller hole than needed for the bearing (i.e. a 1/2" hole), and then welding this to the respective tube. After the welding was complete I would ream to final diameter via endmill + CNC.
This process was a PITA and required a separate fixture for every angle and tube size where there was a bearing, but it did work well. I have to imagine that there is a better and/or easier process to achieve this, but without spending a decent amount of money on special reamers (I already own the machine + endmills) or slitting the bearing housing and using a bolt to clamp tightly around the bearing (which I wanted to avoid) I couldn't think of a great solution... Maybe someone else has better insight here.
I will also mention, regarding the bearing housings, that to keep the width minimal for clearance around the cranks I did 'squish' the ends of the tubes to ovalize them. This probably wasn't necessary, but it was easier for me to machine soft jaws to ovalize the tubes and guarantee I had clearance than risk interference issues between the main pivot bearings and the front chainring.
After getting the front triangle welded together (same process and 80-20 jig I have used for several HT frames) came piercing the holes for the pivot points. With what I have available, I decided the best option was to make aluminum tube cradles (with constant tube centerline height regardless of tube diameter) and place the frame onto the mill table for both locating & boring the holes. Getting the frame oriented in a position where I was confident I could locate the hole positions was tedious, but did work.
For actually boring the holes, I started with a 1/16" undersized hole saw, and followed that up with an endmill to final diameter. I opted to use an endmill because I have never had a holesaw actually cut it's intended diameter (actually in this case I needed clearance to slip in a 5/8" diameter pivot axle and the 9/16" hole saw almost gave me that) and I wanted the fit to be as tight as possible to minimize my chances of pulling out of square when welding. This actually worked out very well but if anyone has a simpler way to do this, please advise.
apparently I can only add 10 images to a single post - will continue this in a reply below
The frame is 150mm, progressive rate, single pivot with a rocker mounted to the top tube and intended for a 160mm fork. I am not the best frame builder nor would I say I have an amazing grasp of bike geometry so I will be brief with this part, but the high level summary is illustrated in the below CAD + LinkageX3 screen shots:



After talking to a buddy of mine who has built many full suspension bikes, I settled on the tubing / steel selection as shown below. I was advised to use a minimum of 0.058" tubing (if not 0.065") anywhere that I pierced a pivot point, and 0.035" straight gauge anywhere I was going to tie in the shock mount.


For bearings, I chose to stick with Enduro MAX bearings because they have a reasonable selection of sizes, are specifically intended for bicycle frames, can be found easily/cheaply, and have higher static loads than typical radial bearings. I used a single bearing at each side of every pivot, with the exception of the main pivot, where I stacked two on each side.
Physically incorporating the bearings into the steel parts of the frame, and being able to jig things properly, in my mind was going to be one of the hardest things to figure out how to do. I opted to experiment with this first before purchasing any tubes/parts/etc. to make sure I had a feasible plan... In the end, what I ended up doing was purchasing 17-4 bar-stock in necessary sizes that I would turn into bearing housings. I started by cutting to length, pre-drilling a smaller hole than needed for the bearing (i.e. a 1/2" hole), and then welding this to the respective tube. After the welding was complete I would ream to final diameter via endmill + CNC.


I will also mention, regarding the bearing housings, that to keep the width minimal for clearance around the cranks I did 'squish' the ends of the tubes to ovalize them. This probably wasn't necessary, but it was easier for me to machine soft jaws to ovalize the tubes and guarantee I had clearance than risk interference issues between the main pivot bearings and the front chainring.

After getting the front triangle welded together (same process and 80-20 jig I have used for several HT frames) came piercing the holes for the pivot points. With what I have available, I decided the best option was to make aluminum tube cradles (with constant tube centerline height regardless of tube diameter) and place the frame onto the mill table for both locating & boring the holes. Getting the frame oriented in a position where I was confident I could locate the hole positions was tedious, but did work.
For actually boring the holes, I started with a 1/16" undersized hole saw, and followed that up with an endmill to final diameter. I opted to use an endmill because I have never had a holesaw actually cut it's intended diameter (actually in this case I needed clearance to slip in a 5/8" diameter pivot axle and the 9/16" hole saw almost gave me that) and I wanted the fit to be as tight as possible to minimize my chances of pulling out of square when welding. This actually worked out very well but if anyone has a simpler way to do this, please advise.

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