Kirk Frameworks

[David Kirk]

Fork tip process - no matter how many times I've done this over the past 32 years I still enjoy it.

dave

[Toddtwenty2]

Thanks for sharing, Dave.

I always assumed that this task was less manual than this picture looks, particularly given how perfectly-aligned your forks are.

How do you measure the side to side requirements for the cut and align before cutting and brazing? This seems like something that would require a very precise fixture, in my head.

[David Kirk]

Originally Posted by Toddtwenty2

Thanks for sharing, Dave.

I always assumed that this task was less manual than this picture looks, particularly given how perfectly-aligned your forks are.

How do you measure the side to side requirements for the cut and align before cutting and brazing? This seems like something that would require a very precise fixture, in my head.

Surprisingly it can be done with very simple and common tools.

The first thing that needs to be done is to find the front and rear center of the fork blade so that the dropout slot is clocked properly in rotation with the oval section of the upper fork blade. I'm not quite sure how to explain how I do this without writing a book but in the end it's dead simple and takes only about 30 seconds per fork blade. The second photo shows a thin Sharpie line and that is the front center of the blade. There is a mark on the backside also just like the front.

The next two photos show where I drew more lines on the blade indicating the position and width of the slot. The rough cuts with the hacksaw need to be in the ballpark but not perfect. I make the slot a bit narrow and then file the slot into perfect alignment so that the slot/dropout are in line with the upper oval part of the blade. This part takes some skill/experience. If you just wing it the dropout will not line up and this makes life difficult. So I cut it as close as I can and then file it into a happy place so that the dropout fits snugly in the slot and the slot is aligned.

Then the bevels are ground into place on a bench disk sander. After that it's a matter of cleaning, fluxing, brazing, soaking and finishing. Once all that is done there is a final alignment task and that is bending the dropout very slightly so that when the blades are placed in the crown and the drops are at the proper 100 mm width that the dropout faces are parallel. I made a go/no-go tool for this so it takes just seconds.

That completes the dropout end of the blade. After that's done the blades are cut to length and brazed into the crown/steerer assembly and POOF....you have a fork.

dave

[madsciencenow]

Such a cool set of pics and explanation, Dave! You are a true craftsman and dare I say, artist with the forks and frames you create!


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[Toddtwenty2]

Thank you for that clear run-down, Dave. I appreciate you taking the time to explain your method. I am quite amazed that such an accurate alignment and precise appearance comes out of a process starting with a hack saw!

Hope all is well.

[David Kirk]

Originally Posted by Toddtwenty2

Thank you for that clear run-down, Dave. I appreciate you taking the time to explain your method. I am quite amazed that such an accurate alignment and precise appearance comes out of a process starting with a hack saw!

Hope all is well.

Many of the best things on life start with a hacksaw!

dave

[sokyroadie]

Great visuals and write up. How do you make the bottom horizontal cut in the slot?

[David Kirk]

Originally Posted by sokyroadie

Great visuals and write up. How do you make the bottom horizontal cut in the slot?

Good morning -

The first time I saw a blade slotted I wondered the same exact thing...and it turns out to be the most simple thing.

First you make the two vertical slots. Then you use some needle nose pliers to bend the tongue outward 90° so that it's sticking out to the front/back of the blade. Finally you take the pliers and grab the tongue and snap it off to the side...it comes right off and you are left with an open slot. The bottom horizontal part is a bit ragged but just 3-4 swipes with a slotting file squares it up nicely.

It's simple, super fast and easy.

dave

[Munger]

Dave:

In the past you wouldn't make an Onesto for a heavier rider. Does the XL model rectify that limitation?

[David Kirk]

Originally Posted by Munger

Dave:

In the past you wouldn't make an Onesto for a heavier rider. Does the XL model rectify that limitation?

Yes....the Onesto XL will happily carry a heavier rider.

dave

[David Kirk]

A few misc photos from this fall....bike stuff, riding views, and car stuff as another race season winds down.

dave

[dave thompson]

Dave, you're having entirely too much fun!

[tv_vt]

Do you race the car in SCCA races? Or something else? What category is that roadster in?

About your great fork photo series - did you leave out one finishing step where you somehow scallop the side edges of the blade tips before brazing in the dropouts? In the finished fork, there's a nice curve to the sides of the blades where they meet the dropouts.

[parris]

HAPPY belated birthday Dave.

[Tim Porter]

Was traveling last week and this blew by me. Happy Birthday Dave!! Loving my Kirk bikes! Tim