Cut the seat post to length.

I cut my seat tube to length today, also slotted it for the clamp.Nice and tidy.

I cut it with the angle grinder and a 2mm cut off wheel.

I also have some 25mmx25mm square that I cut 2 pieces from, then cut one face off the square on each piece if this makes sense?! ending up with 2 U shaped pieces that I then filed and welded together to form a rectangle.
Its for the extension from the bb shell to the down tube, it will also carry the lower shock mount.I will join it with a cut tube mitred to the end of the down tube and then to the rectangle extension.


Square before.

And after the 2 pieces joined together.

And cleand up rough with the grinder.

And this is where it sits on the bike (a little hand filing to do yet!).

I also cleaned up the mitre on the ht/dt joint, it was pretty rough and misalined so I just have to get the centre lines of the tubes sorted and will get this brazed on.I would like to get the bb/rectangle/tube/dt all working on the drawing first before the torch comes out!Quess I could do the st brace, have to buy 2 more hole saws (28mm- 44mm) before this happens.

TT/seat tube

Punctured the TT yesterday, it took some time setting the notcher up centred and straight for the cut it was still off some but I cut it with a 25mm cutter and filed the rest to fit.


Cutting in the jig, was hard to set up.


From the top.


Another angle.

As I said it was off to one side when I had finished the cut, I can see now how a lathe or mill would be so much easier to do these cuts, having the x/y movement of the table to adjust things.


But it filed up ok, and I got the angle right! So last night proceeded with the braze which also went well it lined up good on the drawing, a little off at the bottom (1mm) but I really didn't want to file any more out, got a really good feel for the brazing, having 2 fillets back to back, found the heat control quite easy, torch on, torch off, leave the rod in the flame and near the puddle to keep it a consistant temp, also controling the puddle with the torch and making sure the fillet makes it to the root of the joint.


I cleaned up the junction with boiling water as it was a little hard to soak, which works a treat!
I will head down now and clean it up.

Over the drawing after the braze, looking good.

A little off here, though only 1mm or so.

Heres the frame sitting on my home made v blocks on the drawing.

This is my tube cutter it works well but I don't trust that it always cuts square and centered, so I check it regularly with an old bit of tube and a machinists square.For home stuff it seems good, its nicely made, but a lathe would be preferable.

Head tube/TT junction/Gusset

Well have completed this junction today, but first things first, Squashed the tt from 44.5mm to 35mm with my high tech 4x2 tube press.




I have a new respect for steel now after doing this, I had to squash it to some where around 15-20mm (gap), before the tube came down to 35mm!
Then put it in my tube nocther and cut the mitre, filed and cleaned it up checked the joint for gaps.And basically it took a little time to get them matched nicely but in the end it came up well.





looking tight!

The braze went well, had a little fun with the heat control on the tt/gusset area.The gusset was pretty thin and heated pretty fast compared to the tube below.

First I cleaned everything spotless, then fluxed the joint, baked the flux on with the torch leaving the top of the tt clean for the gusset after, I then tacked the joint on either side of the tt, checked it over the drawing which was all good then I fluxed the gusset and tt tube where it is going to sit and tacked on the gusset, then heated the whole joint and proceeded to do the tinning pass, then on to the fillet.



just after brazing

Something is up with the torch or my regs as the flame changed during the braze and had to set it the flame twice.I think the regs aren't sensitive enough for the torch, will have to set the pressure on the regs again for the next joint.

Anyways just after I had finished I checked on the drawing again and it was bang on so was pretty happy about this, its now soaking will hopefully get to cleaning it up tomorrow, and post some pics.




Hmmm stoked to see it lining up!

BB/Seat tube joint.

Today, got my bb/seat tube junction done.Was fun and kinda stressful, but cleaned up really well and am very happy with it.




Post braze and soak


Cleaned up and ready for next joint

Got my new hitachi hammer drill in the post a week ago, man its nice, and quick to get the mitres done now.
Had a super brazing session last week, blew through one of those cheap fuller holesaws in about 5 cuts!But have got the bacho ones now which seem better made and cut better also.
So I did about 4-5 joints in quick succession and really got a handle on the technique for building those nice big fillets.
Found a great tip on the frame forum the other day, grind the outside of the holesaw to get rid of the offset teeth that stick outside the diameter of the main body for a cleaner cut, it works really well.
Theres a heap of great info on that site if you need to know what the pro's are doing its all there for everyone to see, really is a great site for trolling info.Have spent alot of time there lately!

Think I need to have more heat in the tinning pass but the fillet turned out really well, still had the internal micro fillet coming up the back side of the joint which was is good to see.
Think I even got it pretty square and straight!!


Hmmm okay gotta head off, but next comes the big tube squash, have to squash the TT from 44.5mm to 35.6 so I can mitre and braze it to the head tube, should be fun!