Cat-man-do said:
Brian, A nice job you did modding those old Marwi light heads. I would of sworn ... Any problems with getting the optics to fit afterwards? What optics did you use?
My bad. I beg the OP's pardon. Yes the ID is 33 mm. So it means some work squeezing the MR11 triple with Cute lens in there. I used three 10 mm round MCPCB light engines. I also used separate lenses for each LED in both lights. (More on that later).
PMing EL34 as to whether someone has stuffed the triple MR11 in one, would be a great idea.
I was thinking of the triple optic clearance and went off from there with the post. The Cute lens which would seat where the original MR11 bulb seated. Looking at the pic on Cutter, you might need to cut three scallops just behind the lip on the inside of the light body to clear the frontmost part of the three lens cones where they are widest. Otherwise, it looks like the lens would go. The lens legs should fit a bit inside of inner wall. At most a little sanding would do it.
http://www.cutter.com.au/proddetail.php?prod=cut759
The board is a different story. You'd have to take off 1.0 mm evenly all around to squeeze a triple board in there: 35 down to 33. I polished out about 0.1 mm out to get a copper to aluminum smooth contact as their are small ridges in the 'bore'. But the 1 mm aluminum is about right to spread heat over the body, so I wouldn't make it any thinner.
The MR11 MCPCB triple pic in the Cutter link doesn't show the traces under the mask, but the quad does pretty well. Judging by the quad, it looks like you'd be OK taking the outer 1 mm off the triple. EL34 will know if a customer did this and told him about it. You could use triple 10 mm boards like I did but the alignment would be critical. I'd rather fuss trimming the triple down evenly.
Cat-man-do said:
Anyway, from the pictures on the CPF site, it didn't look too hard to make a heat sink. Of course making it fit snugly looks to be the trick.
Not hard. Just patience. I found a hot plate a great way to solder assemblages. Just line it all up sit in on a burner, heat it up add solder. Done. I melted a little silver solder in the backside of the copper cap before splitting and expanding to increase the firewall thickness a bit (Troutie recommend 5 mm for AL, CU can be less, but not knowing how much less, and not a weight weinie, I opted for a bit of insurance.)
You either build up a 1" pipe cap, or slit it so you can expand it. The sanding and fitting is fiddly but the payoff is more metal-metal contact and a cooler light. The helmet light at 1 amp in flash mode in the day (daytime running light for comatose drivers, 85-95 *F or about 30-35 *C ambient, sun warming black body) feels nicely warm, like the perfect winter hand warmer, so maybe 40 C, after my cool down and a few minutes stopped shutting lights down. About skin temp while riding.
Given a 35 mm aluminum MCPCB trimmed for a tight fit in a 33 mm ID body, I might be tempted to cut the bottoms out of 2 1 1/4 " pipe caps, and grind them to fit and use thermal epoxy to fasten them in as a firewall for th MCPCB to sit on. Or use a 33 mm diameter, 5 mm thick aluminum slug.
Cat-man-do said:
If you didn't need as much throw I suppose you could use a 20mm triple if you were going to bar mount. That might be easier ( for us less able DIY'ers ..

) to work with.
If you are doing two, one bar, one helmet making one a 20 mm based light would be easier.
Borderline On topic:
My optics: My helmet light with aspheric lenses:
http://forums.mtbr.com/showthread.php?t=602133
Thrower works very well. It does not take impact well.
The triple Carclo 10417: great anti-tunnel effect, nasty on the road. Working on fixing it:
http://www.candlepowerforums.com/vb/showpost.php?p=3447006&postcount=319
Cat-man-do said:
Nice job modding those tail lights as well. ( Lots of good ideas there ). Any idea on just how bright they are lumen wise? I don't suppose they flash but would be even nicer if they did. :thumbsup:
Thanks Cat-man-do.
OP: This is OT other than the Marwi housings.
~100 lumens each. About 2 = ~1.3 x a Dinottte 140. The 12 V (AC or DC) driver is for landscape or indoor spot lighting and has no such option. A Bflex to drive both could fix that but would almost double the cost.
Lumens:
http://www.candlepowerforums.com/vb/showpost.php?p=3427754&postcount=108
Brighter than brake lights:
http://www.candlepowerforums.com/vb/showpost.php?p=3428252&postcount=109
Day video:
http://www.candlepowerforums.com/vb/showpost.php?p=3435483&postcount=46
Night video:
http://www.candlepowerforums.com/vb/showpost.php?p=3437637&postcount=48
I hope that takes further discussion of my lights off this thread. I beg the OP's pardon.