That has come up real smooth. I love the attachment method with the orings. I have just twigged onto what you were doing. Very clever.
The thing I like best about this contest is seeing the creative ways that others come up with to solve design problems. You hit the nail when you said “I’ve learned a whole bunch”. It’s one of the points our builds will be judged on, trying new ideas and techniques. Don’t give up on the brazing, the learning curve is steep.
I have made very slow progress for the past month or so. Due to various reasons including design paralysis. I keep finding myself second guessing my plan and also keep thinking of new ideas that would be so cool to incorporate. Now I'm in panic mode and find myself being forced to fall back on my original basic plan. Even then, I got a ton of ground I need to cover.
Tonight, I finally successfully brazed a big piece. Thanks due to Rufusbduck, research, and practice. I discovered my biggest problem was being too timid and not using enough heat. I ended up having to buy a bigger tip and upping the flame size. Even then, I still barely succeeded. I think I got it now and am certain the copper head will now turn into a reality. I have just updated Post 2 (Head).
Tomorrow I will be hopefully be working on this light big time. So there should be lots of other updates tomorrow night.
Keep it up. Sometimes you just have to just wade in and do it. Sometimes you'll step on your d*ck. Often you'll succeed.
Regarding the torch, I've had success using a second torch when one just won't get me enough heat. I've even seen videos with three used.
Keep on Keepin on.
I like that, design paralysis. Theres no stress. Its only a light for crying out loud. Now just take your time and hurry up. 
Thanks for the encouragement. 3 torches (for brazing that is) sounds like something Evel Knievel would do. Some people must have some real long d__s to have to worry about stepping on them.
Got it MRsDNF. Don't stress, relax and stress. OK Done. i now feel quite . . . um strelassed.
Time to start crunching. Will be mixing in mowing and other chores, but intend to put the better part of the day into trying t move this build along. Hope to report back good progress tonight.
Keep it up. You are making a one of kind mega photon pump! And I´d say your progress is good :-)
Im amazed by all your great work!
Keep it coming!
Thank you Ledsmoke and RaceR86. Just finished mowing and yard work. It's quickly working up to over 100 degree F (38C) heat index today. I'm cooled down and heading out to the shed now.
I hope you get to finish it. It's an awesome build! Tell me about how you sand, using the drill and the water bath. I'm interested in the process.
My too. I'm a bit concerned about finishing at this point. It was hot today and progress was slowed by the heat. Updated the head portion. Will try to do some polishing of the fins and lapping where the emitter base will rest.
Wet sanding in water is a great way to keep the sandpaper from clogging up. Just figure out a way to mount to the drill. Start with 320 to shape the item and get rid of scratches and such. Then quick passes with 600, 1200, and then 2000 grit. I use the same process for pieces that can't be mounted in a drill. The water really speeds up the process and doesn't produce dust.
I try to have the piece partially in the water so that it draws up water and continually rinses the sandpaper. If you can submerge the piece, the process is so much quieter. Only the drill motor noise to deal with. Obviously, you want to keep the drill and your drill hand out of the water and dry. You don't want to be a conductor and get electrocuted.
The disks in my case that will be the cooling fins were shaped using the drill, but they will have to be final sanded and polished by hand as the bolt and nut to mount to the drill block access to sanding and create a high point.
For those the use oxygen to weld, braze, etc, who all uses one of these?
They work great and can save you a ton of money. I picked up the above unit for $50USD. Just monitor Craig's List and be ready to pounce when a good deal shows up.
The oxygen concentration is in the mid to high 90's I believe. I would have to look up this unit's specs to know for sure. The flame is just slightly cooler. I still keep a bottle of oxygen handy in case I need the hottest flame, but haven't used it since buying this unit. This unit can put out as much oxygen as I need. Well, I haven't tried it for cutting yet. I want to connect a buffer tank to it just in case I need extra flow for cutting. Thinking about using that small empty oxygen tank on the right for that purpose.
Getting the seam to line up is certainly troublesome. I found that if the parts line up without clamping they are more likely to end up true and that once it is brazed it’s much easier to finish rolling it to an even round tube. Especially if you can fit the part into yet another tube with a rolling bar inside of them. The better the fit of the three, the rounder the tube becomes. I have to say that working such large pieces would be uncharted territory for me so I don’t want to sound like I could do better. You’re doing well so far. Hope you figure the rest out.
So that unit replaces the oxy tank and saves on that refill?
Yes, your hose fittings will screw right to it. Direct plug and play. The unit has a flow control built in. I use that as a type of pressure control, but to be honest, I usually keep it on max as doesn't exceed like 25 psi.
Oh, my unit is the typical 5 liters per minute max flow rate. Oxygen concentration is higher at slower flow rates though. Towards max, I think the concentration drops to the 70's. That is another reason I want a buffer tank. I can set the flow rate low for higher concentration O2 and let the buffer tank give me high flow if needed.
I should have said I bought the O2 concentrator used from a private party. Generally, people want much more than $50 for them.
They are really nifty devices. They use a simple concept of porous zeolite's ability to adsorb large quantities of nitrogen under high pressure. Most of the air around us is nitrogen. After that, it's oxygen and other trace gases. Air is compressed into a tank containing zeolite. Then the free are in the tank is purged under pressure. This purged air are is mostly oxygen and is collected for output. Then the tank is then depressurized and the nitrogen escapes (deabsorbs) from the zeolite. Most O2 concentrators have 2 tanks that are 180 degrees out of phase with each other.
Well, I'm going back outside to do more mowing and yard work. Then on to the scratch build again. Hopefully, I make more progress today than yesterday, but it's going to be another hot one today. The good news is that yesterday cemented the foundation of the light. Now its a matter of the following:
- Drilling some holes
- Polishing the exterior surfaces
- Pressing in copper bar
- Building the emitter base, driver mounts, and cell holder.
- Assembling, final focusing, and testing
Lots of work ahead, but the hard part is done.
I continue to be amazed at the unique nature of each build. Individuality on roids.
Any one have some tips on how to polish aluminum that has already been polished and waxed?
I've hand polished my heat sink fins, but I'm not happy with the result of a couple of them. I know it's because I got tired and rushed. Any way to polish them without redoing the whole process. Thinking about trying a buffing wheel with polishing compound. Just worried I may ruin them. I need them to remain flat for good surface contact.
Possible a different sort of rag may help. I prefer something soft rather than a material like Denim.