Monday, July 13, 2009

Monday potpourri...

Ok, here's a quick riddle for ya.

What's green and gold and dissapears before your eyes?

Scroll down for the answer...

Yep, it's a Reynolds 531 reproduction decal.

Despite what the seller states, these water slide repros do no hold up to solvent based clears.

Mike had provided me with a two of these little guys to place on the blades of his box crown fork. Without a few test pieces, I had to trust the manufacturers claims that they were good to go, obviously they were not. It is quite frustrating to have the finish perfect and then have the decal disintegrate before your eyes. What sucked even more is that although the centers dissolved, the adhesive edges stuck fast and had to be sanded off.

The sanding left a small blemish in the color can see it on the blade just below the crown. Arrh! More unneccessary work.

So, after a bit of cooling off (me, not the fork), I broke out the airbrush and touched it up.

Nice and clean now, can't even tell that there was an issue. Mike can still have his tubing decals, it'll just have to be over the clear coat instead. With the fork repaired now, this guy is ready to go home. Look for an email from me Mike :)
With a few hours of the afternoon left today, I started a local project that I've been pushing to the side for too long. Kalten was in desparate need of a little tutoring before his Algebra finals this spring. Despite my best attempts to work him through the difficulties, the parent/child barrier could not be broached, so I put in a call to Louis who works at the local bike shop, Ride On. Louis, besides being a friendly wrench, is working on his Master's degree in Mathmatics, I felt pretty confident he could help. Anyhoo, long story short, I asked Louis what I could do to pay him for his time...he really wanted a belt drive single speed.
Well with time and budget constraints being an issue, he decided to hook into a Soma B-side 650 frame and have me put a split into it to pass the belt through. I've been tripping over the frame for months now, dusting it off occasionally so I did not feel too guilty, and finally got tired of seeing Louis's sad puppy eyes when I'd tell him, "Nope, haven't gotten started on it yet" for yet another time. So I figured with a few hours left in the shop today, I'd better get it done.

We started off by having Kalten sand off the paint for the area of the seat stay we would be adding the lap joint to.

I dug through the bar stock and pulled out a piece of stainless steel that sat just above the OD of the stay. The piece did not need to be stainless, but I thought that the non-corrosive nature and the ability to leave it unpainted would assist with keeping the joint serviceable for years.

I spun the piece down in the lathe so that it sat about .100" strong, enough that once the piece is turned down to fit into the stay, a small lip will exist to allow me to keep the silver moving down the inside of the stay and damning it a bit the other direction to keep it out of the lap joint.

I then set up the mill and cut out a section of the piece exactly 1/2 of the outside diameter. This will eventually be split and one section turned 180 degrees so that the pieces meet eachother and make a perfect unit.

The piece was then drilled, counter sunk, and tapped to accept a 5mm stainless bolt.

I then lightly sanded down all the edges, bolted it together, and chucked it in the mill to turn down the ends to fit into the ID of the seat stay.

Out of the lathe, now you can see how the piece fits all together.

The sanded frame section is then layed out to match the size of the lap joint and the section cut out with a hack saw and a bit of filing to insure squareness.

The joint was then dry fit, tolerances checked, then removed and fluxed up. We're ready to braze!

Heat control is really important on this piece as the bulk of the lap joint will take longer to heat than the thin tubing of the stay. This is one reason I left the small lip, so that despite the heat concentrated on the piece to keep the tubing from overheating, the mechanical lip will keep the silver from wanting to flow into my lap joint if I misjudge the temperature application. Fortunately, it was a moot point as the silver flowed nicely down into the tube, sealing the piece in for good.

Out of the dunk tank and hit with a bit of scothbright, here you can see how the joint allows the stay to spread so that the belt can pass.

And with the bolt in place...

The frame will get a cream fade towards the drops to blend in the work. Should be a nice economical option to allow Louis all the advantages of a belt drive system on a rocking 650b wheel platform. Can't wait to ride it :) (and before you, I will not be doing retrofits for others, this was a one time special).
Not a bad looking frame...




Sam Correa said...
This comment has been removed by the author.
IF52 said...

That's pretty nifty snifty Rody.

Sad puppy eyes huh?

Cracked Headtube said...

(and before you, I will not be doing retrofits for others, this was a one time special)

very nice work, and problem solving. I like it.

OldNSlo said...

Really cool! Very creative solution!

Anonymous said...

so simple and so sweet. i'm yet again amazed at what you are able to do. i have a long way to go.


denise garro said...

Good to see you in the pics brazing....hope you and the family are well....I look forward to using your sweet bars on a new one speed 650b with a shock....My body is ready for some softness up front...I have tennis elbow for the last 8 weeks now from pounding fence post, kayaking and fishing. it prob. doesn't help riding a ridged onespeed in rocky AZ. Its not easy getting older...We would love to see you again soon...

sean said...

Very clean. Nice work.