Classtime 

In this video, the modification is via welding.
Do you think it can be done brazing with propane which I have?

Andrew R Stewart 

Sure, but that's a lot of cobbed up work to do. I see this as more about doing a project than what you end up with Andy

unterhausen

I think welding would be a lot more durable.

Classtime 

But what I have is Oxy-Propane.

My son would like a lugged steel fixie and this seems less reckless wrt the stays than removing the dropouts.

Andrew R Stewart 

"But what I have is Oxy-Propane."

Then use that and let us know how it went. You asked, we answered. Sorry if the replies are not what you want to hear.

Are we to assume that the bike already has horizontal dropouts as the vid's has? If so are they not long enough to allow chain tensioning adjustments? Andy

unterhausen

Exactly, if it has horizontal dropouts, it's ready-made for single speed. Single speed may be why horizontal dropouts lasted so long.
People used to switch to single speed for winter training. During all my years of riding single speed, I never had rear-facing dropouts.

Classtime 

Thank you for the answers and we don’t have an frameset yet. I always assumed that conversions were done by removing the road dropouts and replacing them with track dropouts. This modification of the road dropouts appears to better preserve the integrity of the original construction and it is nice to know brazing will work. AND projects are enjoyable. Oftentimes for kids these days, it is not about utility but style.

GrayJay

Entirely do-able using brazing and an oxy/propane torch assuming frame was originally brazed and not TIG welded.
The only caution I would have is that if your using the small disposable O2 canisters (like home depot sells) instead or a refillable welding tanks or O2 generator, you will consume the small tanks in matter of a few minutes, the O2 and fuel for those get expensive quickly.
Hacksaw the old dropout in half so you can heat and pull the 2 pieces out of the SS and CS tubes separately without damaging the tubing. You would probably be better off fabricating your own track dropouts from plate steel so they exactly fit your frames inherited geometry. Trying to retrofit pre-made dropouts might not match all the existing angles as well as what you can easily make for yourself, just need to trace out a pattern then go after the plate steel with drill, hacksaw, files to make a nice custom dropout.

Edit- I watched the linked video after above reply. I doubt that their method of modifying the existing DO would work as well with brazing (they used TIG for that). They avoided removing and re-brazing/welding the SS and CS tube connections but I think it would be easier & cleaner just to entirely remove the entire existing DO and start over with a new track-end DO. Brazing flat DO ends to a CS/SS tube is pretty quick and easy.

unterhausen

I think both Henry James and Pacenti had conversion dropouts. I used the Pacenti d/o to convert the first frame I ever built, which I continue not ride. This has been true since I made it in 1975.
I recall that it was an easy conversion, but that may not be true for a novice. I feel like there are still some conversion dropouts out there in people's junk pile. The problem is shaking them loose. It would be pretty easy to get some laser cut. A set of campagnolo (or copies) track dropouts would also work on most bikes.

Andrew R Stewart 

One detail of the Henrey James conversion to track drop outs is that they were offered in three different version. The base version was pretty close in size to Campy's. The next two versions added some material above and ahead of the slot, basically enlarging the tabs. This allowed for a lot of old stay end location WRT where the slot was needed. The larger versions also allowed for some stay end trimming off of.

Making slotted (no der hanger) dropouts is fairly easy and quite doable with simple hand tools. Andy

bulgie 

Yeah or just buy them, sometimes available cheap. Like these, I'll sell them for $30/pair shipped in the US:



Look to be laser-cut. Knockoffs of the old Zeus track ends, which were also sold under different names, dunno who actually made them.
I vaguely remember buying these knockoffs, maybe from Poland? They're ~5 mm thick. The existing slots in the stays probably aren't that thick, so they will need to be filed wider to fit these, some filing skill required. Sorry, I don't have a youtube showing how its done!

squirtdad 

fwiw first fixie I made with my son, used his grandma's old univega frame, removed cable guides, stripped and painted it and kept the dropouts. Key was to use nut's not QR to ensure wheel stays in position.

79pmooney

Is this bike going to be ridden on the velodrome? Or is it road only? If road only, why? Horizontal dropouts work far better. Proper nutted hubs don't slide in plain steel dropouts when the nuts are tight. (I cannot slide them in a much more slippery titanium dropout. I tighten them with a standard "peanut butter" wrench. When I was much younger, much stronger and much tighter on budget, a 6" Sears crescent wrench served me for years.) And road dropouts allow quicker, easier wheel removals.

Yeah, I know - the young have to have what's hip. Boring and practical need not apply. This is a fun project. And my run of convincing perhaps two people that road dropouts actually work better on the road will stand another year.

Edit: on the use of quick releases on fix gears - again, keep it simple. Don't. It's not a slippage issue. QRs just make it harder to set the chain slack and room between the chainstays properly simultaneously. With nuts, you pull the wheel back, slightly tighten one, center the wheel, check slack, and then you can "rock" the wheel, loosening one nut at a time to adjust the slack very easily and accurately. Sounds tedious. Trust me, in any situation where you are down brain cells, it is FAR easier. Also, if the road dropouts are one of the better ones, it will have the dropout screws. If you don't change cog sizes, you can set the screws to a centered wheel and proper slack. Makes late night wheel replacement in the rain and after beers really easy. (Down brain cells - the common state after riding your fix gear in a 42-23 gear up a tough hill. At the top you flip the wheel to the 12 tooth for the descent. But, many of those brain cells are back there on that last climb. And you are thanking yourself that you didn't go to the track ends - except you are too spaced to remember.)

JohnDThompson 

Laser or water-jet cut from steel plate, I'd guess. The Zeus Pista dropouts were forged, and the tabs tapered to better fit in the stays. Still, some of the nicest-looking track dropouts made.