p7 build-last min questions

ok the moment of truth has come. ive looked at every p7 build thread i can find but i still have a question or two.
https://www.candlepowerforums.com/threads/195358

1. in the p7 build thread above he goes into detail with circuits but im doing a dd off 3d's. do i just find the positive from my switch and wire it to pos on the led and skip all the stuff in the middle. if so, do we happen to have a p7 dd build thread. i've looked. it would be nice to see exactally what i'm doing cause i have no creativity in this field

2. glue vs compound
http://www.dealextreme.com/details.dx/sku.4579 glue
http://www.dealextreme.com/feedbacks/BrowseReviews.dx/sku.4593 comp

i assume i use a thin layer of glue to seat the led to the heatsink, and compound i just goup in between the heatsink and the body of the light to disipate heat. well can i add just a little compound to the glue for future mods, say 80%glue/20%compound so it wont be impossible to replace led in the future. if so, does it work the opposite where i can add a little clue to keep the compound in place.

thanks,
jason

I have a question. Do you have an anodized heat sink?

I would sugguest using some Artic aluminumn to mount your P7 regardless, compound would be used between the HS and thmag body. Make sure you check for continuity if your HS is not anodized.

Three D alkalines will not hold up for long with such a high drain and will sag quickly. If you want to build on the cheap use a DX board at 2.8 with NIMH batteries. If you were using 1 D Li-ion the DD would work. 3 NiMh batteries do not have enough volts and 4 are too many for DD.

Waiting for your reply.

jasonsmaglites said:

ok the moment of truth has come. ive looked at every p7 build thread i can find but i still have a question or two.
https://www.candlepowerforums.com/threads/195358

1. in the p7 build thread above he goes into detail with circuits but im doing a dd off 3d's. do i just find the positive from my switch and wire it to pos on the led and skip all the stuff in the middle. if so, do we happen to have a p7 dd build thread. i've looked. it would be nice to see exactally what i'm doing cause i have no creativity in this field

2. glue vs compound
http://www.dealextreme.com/details.dx/sku.4579 glue
http://www.dealextreme.com/feedbacks/BrowseReviews.dx/sku.4593 comp

i assume i use a thin layer of glue to seat the led to the heatsink, and compound i just goup in between the heatsink and the body of the light to disipate heat. well can i add just a little compound to the glue for future mods, say 80%glue/20%compound so it wont be impossible to replace led in the future. if so, does it work the opposite where i can add a little clue to keep the compound in place.

thanks,
jason

Click to expand...

Q1 Yes
Q2 OK for none critical low heat applications no good for a P7 use AA
P7s get hot don't shortcut anything to do with heat sinking, use Arctic Alumina epoxy you won't regret the $s. :twothumbs
Norm

Actually many have made a 3D P7 Direct Drive Mag that runs fine off of 3 NiMH batteries. I done it without any problems. Elektrolumens also sold modified 3D Direct Drive Maglites before. So it can be done. In order to use the cheap KD 2.8A circuit board, you need to use it in a 4D (4.8V to 6V) Mag for optimal performance.

yea, i dont know much but i know i'm pretty much gonna be ok with 3d dd. maybe my next one will be a 4d with resistor for a slight overdrive, or better yet, i'll wire a circuit or control board in between.

so you guys are saying scrap the glue i just got from dx? that sucks, it took so long to get all the parts here. does it break down under the heat? if you think it will do for my first build, or even that i'll be able to redo it later i'm going for it. but if you're thinking it wont get the heat to the heatsink and overheat my led, well i really dont want that. either way i'll order the artic aluminum, but let me know why you're thinking this glue wont cut it.

I have made plenty that run off 3c nimh cells. I would recommend getting high quality cells though like 3500mah or above...

Definitely use straight Arctic Alumina for the emitter. You can use any thermal grease for the sink/host. I make a mixture of grease and AA so the sink stays in good but can come out with force if needed

I just dont trust that thermal silicon stuff because there are no heat transfer specs

spc (and others),

thanks for the advice. the mixture of glue and thermal paste is exactly what i was trying to confirm i should do. i want enough glue in there so it's not just goop lying loosely around in there.

it does however really seem silly not to use this glue since its here now and paid for. it says its for thermal coupling of electrical device to heatsinks. high thermal conductivity low bleed stable 50ml. if it took IT'S word for it, it would be fine,lol. i guess just no one has used it to know if it performs well?

What bin is the P7? I or J?

you will do fine with the 3D NIMH, I use 10000mah tenergy and get close to three hours run time. They now make 15000 mah batteries that will last even longer and yes that is about all Electrolumens uses.
The driver for P7 take more juice than you have just to funtion.

As they have said use AA for the emitter or a combo of AA and Arctic Aluminum as some do. The best stuff for putting on the surface of heatsink where it slides in the host is Artic Ceramique it does a great job and allowes removal of the sink.

The grease you got from DX is a silcone based grease and never hardens, I had trouble with it melting and letting the sink slide in and out if the host was shaken, the other problem is I have had the silicone when it got hot leave a film on the reflectors.
You have a good handle on what to do now it is time to enjoy it you have the knowledge.

When you get that one done on the next if you want dimming you can hook a D2flex to thouse NIMH builds and have up to 8 brightness settings.

ok, guys i'm gonna need two links to proceed.

1. is there a thread posting how to do a dd 3d p7 build. i thought for sure there was one but haven't found any. the link posted above uses a driver and doesn't even show how to take the switch out of the mag host. sadly i've never done that

2. where to buy aa, artic aluminum, and artic Ceramique. (i really only need 2 of these right? which 2?)

also i've never seen 15000 mah d cells. where are they at and has anyone tested to confirm. will you get 15000 mah out of them at a high drain like a dd p7 build, or only at slower discharge rates?

3rd_Shift wrote a tutorial on the exact build your doing
Artic aluminum, and artic Ceramique can be brought in the Marketplace,
look for Photonfanatics sales thread in the Dealers section

Battery Junction or Battery Station are good places to look at the batteries. I got my Tenergy 10000MAH there and have been very pleased.

Here is a link to Battery Junction but they only have up to 12k

http://www.batteryjunction.com/dnireba.html

Dave

ok. i must be the stupidest person on this entire forum. i've never taken out the switch on a maglite and i'm having trouble. its sad being stopped this early. i found a 5/64th allen by some miracle of me wanting one of every tool to tinker around with despite not knowing how to use them. i've spun and spun the nut inside the mag switch but i still cant get the switch out. i know i'm just doing it by hand but even without a wrench or drill i must have done 100 revolutions.

(2 min later)

i've just tried using a cordless drill, even marking a spot on the inside of the switches nut with red marker to ensure that i was turning it and not in fact just stripping it. what am i missing in taking the switch out of this mag.

ok. here was my problem. i was using a bit with a 5/64th allen tip on it. the deal is it's not there on the switch where you can see that you're actually loosening it. you need a long shank 2mm (possibly also a 5/64th) to get deep into the mag body and thats where you loosen the switch.

i now have the switch off and will continue later tonight. i almost edited out my ignorance in the post above but i have a feeling that that's gonna happen to someone else and wanted the maglite switch for dummies verision to stay in case someone can benefit from it later.

LOL exactly the samething happen to me the first time I tried to
dismantle a Mag :thinking:
I thought I had the wrong size Allen key

tx101 said:

LOL exactly the samething happen to me the first time I tried to
dismantle a Mag :thinking:
I thought I had the wrong size Allen key

Click to expand...

You see that's were 3rd_shift's tutorials come in handy. In all of them, you clearly see pictures of the a 5/64 short arm hex key tool going into the switch along with his explanation of what to do. I too originally just used a hex bit before looking at the tutorials. :duh2:

See here...

https://www.candlepowerforums.com/threads/144921

https://www.candlepowerforums.com/threads/171366

https://www.candlepowerforums.com/threads/144087

https://www.candlepowerforums.com/threads/144087


You should find some helpful information here... YMMV.

Gordon aka:skillet

(pic deleted- messing thread up resolution wise and no longer needed)

hey guys. need your expertise again. here is a pic of my soldering job to the modded mag switch. i couldnt get the wires to actually touch the connections on the switch, there is a little solder in between. will that be ok? also, all i could find for wire was old headphone wire. i was eager to get started. should i double up on it. what is the downside to using wire too thin. will it not transfer as much energy. im assuming it will raise my resistance, therby giving me less voltage to the led, but increasing my runtime as a result. does that sound right? is there a way to test the led before banging the heatsink assembly into the mag?

also, im about to mix up 2 part artic epoxy to lay the led on the heatsink. i dont need ceramic or anything neutral in between because brightlumens heatsinks are annodized right? i'm assuming thats what that is there for. so i can mount right onto the heatsink. i want to test the led. once i get the switch in the mag, then i can wire the heatsinked led, then i can test it before banging it into the mag right?

i just realized the heatsink has to be installed before i test the light. so i guess i'm just banking on my solder job. (which ive never really done this before) since i dont have any other wire, should i double up on the wire, or wait till i have thicker wire, or go ahead with what i've got, it will be fine?

I dont think the wire your using is going to be a problem
By the looks of it, that bellwire is at least 18 gauge
I went on Wquiles recommendation and used 24 gauge wire
on a DD P7 Mag build ...... 24 gauge is alot thinner than that wire
your using.
What heatsink are you using ???
The sinks I have used require you to install the Mag switch first, then solder the power wires to the emitter, which has already been epoxied
to the heatsink. It is at this point you can test your light, if everything is ok then
you can install the heatsink.
A easiler way would be to install the Magswitch back into the Mag, put some batteries in and use a DMM on the wires you have soldered
Click on .... the DMM will get a voltage reading
Click off .... nothing on the DMM