Here it is, fresh out of its clamps, the two halfs finally fixed together with the metal bits and the rear stays all in ONE PIECE!
The frame all in one piece for the first time.
And a vid of the frame.. all in one piece for the first time.
What this really means is that the project has taken a massive step into the final phase. Sanding off all the resin seapage, and final smoothing to make it ready for varnishing.
I could put it together and attempt to ride it, but really I need to put the saddle in and the final strengthening bolts in the topof the stays. Its going to be tough, but I am going to resist.
I got to a point of no return, having got all the metal work finished, the final laminating of the main frame was upon me.
Prepping for the final epoxy fix on the main frame.
It meant a lot of guess work around the amount of resin I would need to mix up for the job, and in the end I was slightly short and had to do a hasty additional mix. The west system epoxy I have been using has been great, really easy to use at every stage. I put in the metal head tube and bottom bracket sections after the initial 'wetting up' and from there there was no going back. It was just lining it all up and clamping it into position, then cleaning down any excess epoxy after clamping from around the metal parts that I would nor be able to sand back later.
All clamped up, just need to wait for it to go off.
Head tube with decal, fixed in, no going back.
I also managed to get the back end all lined up, and fixed with epoxy the day before. It was slightly less nerve racking, although I don't know why because technically it was harder. However it all worked out. I had drilled small holes in the inside of the metal drop outs where they join the hanger to allow excess epoxy to squirt out, as the fitting with the wooden frame was too tight at the join to let it out. It allowed me to put plenty in and not worry about a dry join. When I was fixing them together I measured from the center of each stay where it joins the frame, to the end of the drop out to get them centered. I also delicately popped the wheel in to see how it lined up, it was good.
Back end all epoxied together.
Next steps are to fix the main frame and back end together, to have THE WHILE WOODEN FRAME together as one for the first time. Then to do final shaping and sanding ready for the posh yacht varnish I have procured.
A bit of progress. Firstly I cut some rear stays and tacked them onto the main frame. The main reason for doing this was to ascertain whether the crank would clear the bottom stay. I am pleased to say it does. See the vid.
Crank clearance test.
The other reason for tacking on the stays was to see if they lined up and would actually fit. They did, so I made four more. Each stay will be made of three layers of the 12mm birch ply.
Rear stays all cut.
I spoke to the resident mechanical engineer at work about giving me some help with the fabrication of the bespoke metal fastenings. He had a great idea about how to connect the stays to the drop outs. I had always been worried about weakening the stay by drilling it, his suggestion was to make the end of the stay round and slot it into a metal tube that in turn would be welded to the drop out. I like it, quite simple and will maintain the strength of the stay.
After my last post, I did get the epoxy I wanted, even if I did have to cycle to the other side of town. I bought a small kit of West System Epoxy to learn how to use it. So the first thing I did today was to mix up a small amount (30ml) and have a go at laminating three strips of off-cuts. I found it easy to use thanks to the very clear instructions. I haven't gone back to see how strong it is but I am confident it will be fine.
Epoxy Resin test.
But the big job today was to split off the two outer layers of the main frame and to reduce weight by cutting out as much as I dared. The idea being that when the outer layers are laminated on top it will create a box section and maintain strength but loose weight, as the frame is really quite heavy at the mo.
Drilled out.
Shapes cut with jig saw.
I drew on the shapes I wanted then drilled out the main cavities. I then trimmed out the remaining bits with a jig saw. What I didn't do was weigh the frame before and after, but it has made a huge difference. I like the look of it. My son asked why the whole frame couldn't look like this. Its a good question, I think it would look great, but I don't think it would be strong enough. I think the box section idea is vital, as I think the frame would flex too much if opened up like this. Also I would have taken more care on the cutting had that been the plan. Next time maybe.
Just the curve around the back wheel, head set groove to drill out and the rear stay shaping to do to complete the wood work. Metal work next. Then fix it all together.
So I did it I took the saw to my quite expensive piece of ply wood. It is the bit I have been looking forward to the most in this whole wooden bike building project. The first cut. I used the card board templates to mark out and just got stuck in. As it turns out I have enough ply for a second attempt if I make a boo boo on this first attempt.
I cut two pieces from the same template, which are now mostly the same shape. Next I need to temporarily fix them together so that I can shape them to be exactly the same shape. This will also include detailing and trimming to reduce weight.
I also marked out a rough template for the rear stays, but they are not cut out yet, the video shows the two parts of the frame, cut and lying together.
I have decided to use West Systems Epoxy in my build. It looks like it will do everything I need. Most of all they put out a really great info booklet and DVD to help first timer like me. The main place the epoxy will be used is to join my two halfs of the frame and probably to reinforce internal sections I router out for weight saving.
