Rick Wianecki builds 
the Frank-n-liner

By Rick Wianecki
 1-Design and mold     2-Fairing    3-Subframe    4-Tub    5-Drivetrain    6-Attach Top   7-Bodywork   8-PreRace
Drivetrain, steering, seat
Sept.1, 2006

Several weeks have passed since I had some time to work on this project and it is time to get this thing running so it can be raced at the Ohio races in early October. I need to bond the adjustable bottom bracket sub-assembly into the front sub-frame. I clamped a piece of wood to one side of the opening so I knew the bottom bracket assemble would be flush with that side and positioned the sub-assembly in the opening in the carbon fiber.
To hold everything in place I cut up some carbon fiber scraps in ½” to ¾” pieces, these pieces will be mixed with epoxy and will be used to bond the bottom bracket in place. I call this mixture “Dragon’s Hair” (DH). I know Dragons do not have hair but if they did it would be just like this stuff when the epoxy cures.
Once the CF scraps are mixed with epoxy I use it to fill any gaps between the BB sub-assembly and the carbon sub-frame. The holes drilled in the square tubing are there to provide areas for the DH mixture to bond to. When everything is set up the High spots will be sanded smooth.
Now it is time to press the spindle bearings into the shell. The bearings fit up against a machined boss at the center of the bottom bracket shell. An aluminum spacer the thickness of the boss is added between the bearings.
 
After both bearings are pressed in I and insert the spindle. To do this I placed the spindle in the freezer overnight and it slid right in.
This picture shows the chain ring side crank arm placed on the spindle. Several spacers will be used to get the required clearances. The crank arm bolts are used to tighten everything together and to keep the bearings from sliding out of the shell.
 
Several spacers were made before one with the correct thickness was found to provide the proper clearances. 
While assembling the bottom bracket and crank arms, the clearances required special attention. Everything rubbed at first. All the connecting bolts spacers and washers had to modified or ground down to get the assembly to spin smoothly. This took a very long time to get sorted out.
 With everything mounted one can see the chain barely clears the front sub-frame. I think there will be some noise from the chain hitting the carbon. I will see about mounting some rubber pads to absorb come of the noise.
I am now going to try and get the rear sub-frames mounted to the tub. I cut several pieces of .10” plate on my horz/vert band saw. Then holes were drilled in the plates to provide additional bonding areas. 
The plates were then brazed to the support tubes that I fabricated earlier. I ended up making sliding end sections so I could get the ends in the proper position for bonding to the tub.
This picture shows one of the rear sub-frames fitted to the tub. This was the final fitting before the main tubes were painted.
 
After the tubes were cleaned and the mounting surfaces covered in tape the remainder of the sub-frames were painted silver.
A string line, level and tape measures along with a lot of visual sighting were used to make sure the rear wheel was centered and level in the tub.
Is it straight yet? 
After the alignment was checked numerous times the sub-frames were attached to the tub with some of the “Dragon,s Hair” Mixture. Additional layers of carbon cloth will be added over the mounting points later.

 
Sept 08, 2006
Before I bond the front sub-frame to the tub the attachment points for the step-up gears and the chain idlers need to be determined and inserts fabricated. I need 2 hard points in the CF sub-frame. I decided on machining them from 1”round 6061-T6 stock. The stock will be turned down to ½” leaving a I” diameter 3/16” thick boss on one end and threading the other end with a ½”x20 die. I then made a knurled threaded end piece to hold the insert in place on the sub-frame. This picture shows one of the two inserts with an additional spacer. 
Here I assembled the insert and spacer with the step-up gear set to see how everything fits. 
This picture shows what the cured Dragon’s Hair looks like before sanding at the top of the head tube. In this state caution needs to be taken in handling to prevent fine carbon needles from entering ones skin. These areas will be sanded with 80 grit sandpaper to smooth the surface before a layer of carbon cloth is added.  
After all the areas have been sanded on the front sub-frame carbon cloth is added to reinforce the areas and the sub-frame is placed in a vacuum bag to insure bonding
Once the additional carbon is cured on the sub-frame ½” holes were drilled at the locations for the Inserts. 
The inserts are shown here on the drive side or the sub-frame. 
Here is the backside of the inserts. The knurled nuts are tightened to hold the inserts in place. During the final assembly epoxy will also be used to secure the inserts. 
This picture shows the components assembled on the sub-frame to check the fit and clearances before the sub-frame is bonded to the tub. 
I mixed up another batch of carbon scraps and epoxy. 
The mixture is applied to the bottom of the sub-frame. Before I did this a sanded the bottom of the sub-frame and the bottom of the tub with 80 grit sandpaper and wiped everything down with acetone. 
The sub-frame is placed in the tub and additional “Dragon’s Hair” is applied to create a fillet between the sub-frame and the tub. 
Before the epoxy cures, the alignment of the sub-frame and the tub is checked and adjustments are made as required.
The sub-frame will be braced at the bottom front. Two ½” foam stiffeners were cut and fitted to the shape of the tub. The stiffeners were covered with a layer of carbon cloth. 
The stiffeners were wetted out with epoxy and placed in a vacuum bag to cure overnight.
The stiffeners were attached to the sub-frame and tub with strips of carbon cloth and epoxy. Additional strips of cloth were added to the entire connection of the sub-frame and tub. 

Next I will fabricate the steering linkage, handle bars and drive train components to get the tub rolling.
October 1, 2006
The steering for the Frank-n-Liner will be adjustable up and down and in and out. This will allow for a custom and comfortable fit for the rider in the tight confines of the shell.

I started out by cutting and shaping 2 -1/16” thick pieces if steel plate. These will be brazed to a 1-1/8” diameter tube to provide a pivoting support for the main steering tube. 		 
Here is the completed pivoting support tube test fit on the carbon steering support bracket. The tube has a slot and pinch bolt to allow a 1” aluminum tube to slide in and out and then be locked in place.
Next the carbon steering support bracket is bonded to the front sub-frame of the tub. Two pieces of plywood are covered with thin plastic to act as a release and align the bracket. Dragon Hair is applied to the mating surfaces and strips of carbon cloth were added in the outside. Once clamped the bracket is left overnight to cure.
A coupler nut is filed to create a groove and will be brazed to section of 1 1/8”steel tubing. The main steering assembly will be aluminum tubing that will have steel mounting brackets clamped on the ends. 
Here the coupler is clamped with a vise grip pliers to the 1 1/8” tube before brazing. I have a special vise grip pliers that is only used for this task.
I use whatever works to hold pieces in position prior to brazing. Here a piece of 2 x 2 pine is supported off the wall and rest on to a tube for brazing.


The fork steerer tube is 1’ thread less. I will use an aluminum collar clamp with an arm attached to control the front wheel. A machine screw is turned down to fit inside a 3/8” tube. These are brazed together and will be assembled to the clamp.
 
Here the collar is shown assembled with the steering arm. Also shown are some additional clamp assemblies that will be used to attach the rod ends.
To attach the rod ends to the steering tubes, special fittings were made to fit inside the tubing that are threaded to accept ¼” rod ends. The pieces were turned and then threaded on my 3-in1- tool.
The fittings were epoxied into the steering tubes. Once the epoxy cured 1/16"’ steel role pins were added to additionally secure the fitting to the tube.
This is a front view looking at the steering assembly at the fork. The collar id clamped to the steerer tube. The rod end is able to slide on the steering arm to change the steering ratio.
Now that the steering parts are all assembled some sort of front support will need to be fabricated. The rear pivot by it self does not provide enough clamping force to hold the steering position.
A U-type clamp will be positioned near the back of the sub-frame. This clamp will be able to slide up and down to provide some additional fixity. The brace is made from 1” wide 1/16” thick aluminum bent into a long U with slits cut in its sides. Here the slots are being cut.
 
Here the clamp is placed on the main steering tube and over the back end of the front sub-frame. A bolt will run through the slots and allow for adjustability.
This picture shows the completed steering looking toward the front.


Next will be mounting the seat and the rest of the chain idlers. We are putting the tub on wheels for the first time and test fitting Frank to see if he is really going to fit.
 
October 6, 2006
The seat I am using is one that Garrie Hill made to fit Frank for another project. The seat has to be mounted so it can be removable and has clearance under it for the chain and Idlers. The seat is positioned in the tub at the proper angle and portions of the seat pan were trimmed to fit inside the tub. This left about 1 1/4” clear under the lowest portion of the seat for chain clearance. 
 
A front mounting clip was fabricated to attach the front of the seat to the front sub-frame. The clip is designed to allow the seat to be moved front to back about 2”. 
A strip of sand paper was glued to the back of the seat. This will allow the forming of a foam support. 
A block of 1 1/2” foam is run over the sandpaper to form the profile of the seat back. Several blocks were formed to create the desired support. 
Two foam pads were glued to the tub and then covered with carbon to provide support for the rear seat brace. Each pad is 1 ½” wide and 3 “ long.
After the epoxy cured on the seat support pads the foam support was checked for fit. Additional foam was sanded off until the support slid on the pads freely.
The sandpaper was removed from the seat back and foam seat support was then glued in place. The foam was covered with two layers of carbon cloth and epoxy. 
The rear idlers need to be mounted to the tub to guide the chain under the seat. Two aluminum brackets were bent and attached to 2-6” idler pulleys. These were poisoned in the tub under the seat.  
A string was used to align and position the idlers for a proper chain line. 
Once the Idlers were aligned the pulleys were removed and a fixture was used to hold the aluminum bracket in place while they were bonded to the tub. The aluminum legs of the brackets were isolated from the carbon tub with 2 oz pieces of fiberglass.  
October 8, 2006
Now it is time to see if Frank really is going to fit in the tub. The clamps and alignment angles were removed from the rims and the wheels were removed from the tub. Tires and tubes were added to the wheels and placed back on the tub. The slots for the wheels had to be enlarged for the tires to fit. The Tub was placed on its wheels for first time and rolled out side into the sun.
Everything seamed to roll smooth and we did not notice any misalignment the front and rear wheels. Those strings really work!
The rear wheel is going to be a 650 with a Rohloff hub. A special set of dropouts were made to mount the wheel. One problem encountered was that I could not get the wheel into the tub with the skewer in place. So a hole was drilled in the side of the tub to insert the skewer from the outside. This picture shows the rear wheel and the seat support. 
Time to see if Frank is going to fit. From the front everything is OK. It's a little tight but this is racing...
From the side. Frank will have to get a pair of racing jeans to help with the slight clearance issues at the hips. Frank says there are no problems. 
10/21/06
Now it is time to get the tub running on it’s own (Frank’s) power. When Frank was test sitting in the tub I noticed some play in the steering linkage. This turned out to be from the threaded tube rotating in the 1”collar. I drilled a 1/8” hole and inserted a role pin to prevent any future movement.
 
Next up is to mount the brake leavers. I e-mailed Rick Gritters and asked for advice on how he mounts the center brake levers on the low racers he builds. Rick e-mailed me several pictures and some great advice. First I cut the mounting clamps off the set of brakes levers that I am going to use.
When cutting of the clamps care was taken to leave enough material for the return spring to seat.
A 3/16” steel plate was attached to a modified steering arm. I modified the steering to provide 2” of tiller and some additional hand clearance. A hole was drilled for a piece of #10 x 32 all thread rod that will secure the leavers. The bracket will receive some lightening holes before it is painted.
The levers are mounted to the bracket through the existing holes in the lever body. A locking nut is used on both ends of the threaded rod.
Once the levers are mounted they are adjusted for clearance and reach. Then sheet metal tabs are brazed to the bracket to prevent the levers from moving out of position.
The shifter and brake levers are now ready to receive their cable and housing.
When bonding in the rear idler support bracket, my intent was to use 2 - 6” idlers at the rear and 2 at the front. I ran the chain and noticed that the rear idlers were not aligning the chain properly at the rear hub. It worked but I thought the chain had too much deflection on the power side and on the return the chain barely touched the return idler.
The solution was to replace the 2-6” idlers with one 4” idler. This Idler was shifted over to align the chain with no deflection and it allowed the return chain to pass without any additional idlers.
Here is a close up of the rear Idler mounted in the existing idler support brackets.
Now the pedals work, the rear hub shifts and the brakes work. The last thing to do is to enlarge the cut out for the front wheel so the tub is steerable. A paper pattern was used to determine where the tub cut out needed to be.
After the carbon was cut away the fork and wheel were reinstalled and clearances were checked. Additional carbon was removed as required.
10/22/06
Frank came over on to test the tub with his own power. The weather was cold and wet but we decided to test the tub anyway. Frank changed into some “Racing” pants that provided him with some additional clearance in the tub, this picture shows Frank getting ready for the maiden voyage. No landing gear is planned for the bike; the front part of the top will slide forward so Frank can put his hand down to start and stop.
Frank peddled off and he slowly gained some speed. The tub appeared stable at slow speeds, and did not wobble as Frank accelerated. Frank said the bike was easy to control and had enough steering to make 90-degree corners in the subdivision.
Frank Made several trips around the block gain speed. Because of the wet conditions we decided not to push our luck and cut the testing short. The tub worked great and only need some minor adjustments.

Next step is to get Frank to finish the sanding on the top part of the bike and get it fitted to the tub on the final construction page. 

Back to the HPV projects page