Part Sourcing Assistance/Advice Thread

[n_maher]

Here's the full range from parts express.

http://www.parts-express.com/cat/speaker-cabinet-spikes/317

Ebay also has some interesting options.

[Earspeakers]

PCB Test point Jacks:

 

I got this one from 

 

http://www.mouser.com/Search/ProductDetail.aspx?R=11011-Rvirtualkey53400000virtualkey534-11011-R

 

Teflon post with copper center, I thought this must be for a bag (none of the documentation was clear). Nope, it's for a single jack! Mind you the jacks are beautiful, the perfect test point jack and easy too use but obviously too expensive. 

 

Any other sources? I've trolled Mouser but haven't found anything similar. 

[GeorgeP]

These are way cheaper at Newark.

 

If teflon is not a priority, these are from Mouser and work fine in the DIY T2: http://ca.mouser.com/ProductDetail/Keystone-Electronics/6038/?qs=sGAEpiMZZMsQtlBhqKq43TNyVdQaQ6rh

[johnwmclean]

I'm after some help with my latest chassis design.

It's an off board KGSSHV, in which Camexpert will be fabing all the panels and drilling the heatsinks.

Which leaves me to create all the brackets, I've bought 16mm equal angle x 3mm x 1 metre lengths.

Cutting is a no brainier, I've bought a little metal mitre box for this.

It's the accurately positioning of the drill holes is where I may struggle, with my limited knowledge and tools, this is my plan...

I have 100% accurate paper print outs of the drawings, which I'll use spray adhesive to stick on the brackets, the quick test I did last week proved to be a good technique for accurate hole location.

I plan use a Stanley knife to cut a cross for the centre of the holes in the aluminum.

Then using a automatic centre punch as starting point in the middle of the cut cross, which I'm hoping to find the exact centre by feel.

This is where I start to get nervous, I bought several #2 centre drill bits to make a pilot hole using a drill press.

From what I've read and watched, it's best not to clamp down the aluminum, instead it's best to let it float on the drill press and let the centre drill bit grab the metal and find the punch hole. Bearing in mind the spinning bit would be very close to punch proximity to enable this, doing an alignment beforehand.

Then finally a pass through with the final drill bit size, an M3 or M4, again with the piece of aluminum floating on the drill press.

That's the plan, sorry it's so long winded, am I on the right path?

[DefQon]

Here's the full range from parts express.

http://www.parts-express.com/cat/speaker-cabinet-spikes/317

Ebay also has some interesting options.

 

Those prices are so cheap. Compared to here. 

[Pars]

I'm after some help with my latest chassis design.

It's an off board KGSSHV, in which Camexpert will be fabing all the panels and drilling the heatsinks.

Which leaves me to create all the brackets, I've bought 16mm equal angle x 3mm x 1 metre lengths.

Cutting is a no brainier, I've bought a little metal mitre box for this.

It's the accurately positioning of the drill holes is where I may struggle, with my limited knowledge and tools, this is my plan...

I have 100% accurate paper print outs of the drawings, which I'll use spray adhesive to stick on the brackets, the quick test I did last week proved to be a good technique for accurate hole location.

I plan use a Stanley knife to cut a cross for the centre of the holes in the aluminum.

Then using a automatic centre punch as starting point in the middle of the cut cross, which I'm hoping to find the exact centre by feel.

This is where I start to get nervous, I bought several #2 centre drill bits to make a pilot hole using a drill press.

From what I've read and watched, it's best not to clamp down the aluminum, instead it's best to let it float on the drill press and let the centre drill bit grab the metal and find the punch hole. Bearing in mind the spinning bit would be very close to punch proximity to enable this, doing an alignment beforehand.

Then finally a pass through with the final drill bit size, an M3 or M4, again with the piece of aluminum floating on the drill press.

That's the plan, sorry it's so long winded, am I on the right path?

I struggle with this myself. Even with accurate center punches the bit seems to want to walk. Interesting concept to let the part float. I'll have to try that as I think that could help.

[guzziguy]

Here's the full range from parts express.

http://www.parts-express.com/cat/speaker-cabinet-spikes/317

Ebay also has some interesting options.

 

Thanks, Nate.  I eventually went with Dayton Audio DSS4 Black Chrome cones.

[chiguy]

I struggle with this myself. Even with accurate center punches the bit seems to want to walk. Interesting concept to let the part float. I'll have to try that as I think that could help.

 

Same struggle as well.  I've been using a hand drill to start the first hole and then using the drill press to enlarge.  I'm also using a cross slide vise on my drill press to allow adjustment while having it clamped down. 

[dsavitsk]

Why don't you have Camexpert drill them if they need to be so precise?

[kevin gilmore]

when i do them, its a 3 step process per hole. which is why it comes out so nice.

even though i'm using full up commercial NC mills, if i just drilled the holes single

step, it would not be perfect.

first you use a centering drill

then you use a small drill bit

then i machine each hole round with the mill bit

now it really does not have to be this perfect, but its only a few minutes extra per

bracket

[JoaMat]

/

Edited November 11, 2015 by JoaMat

[n_maher]

first you use a centering drill

 

 

The step alone helps a lot, at least in my experience.

 

That said, I'm with Doug.  For something that has to be dead-nuts, just have someone with the right equipment do it and don't drive yourself crazy.

[luvdunhill]

I use a jig, similar to what people use to drill holes in bookshelves. It's cut from stainless steel and has different diameters for through hole, tapped holes, etc. I simply do one hole by hand on either end, then screw in the jig and go down the line.

[Craig Sawyers]

when i do them, its a 3 step process per hole. which is why it comes out so nice.

even though i'm using full up commercial NC mills, if i just drilled the holes single

step, it would not be perfect.

first you use a centering drill

then you use a small drill bit

then i machine each hole round with the mill bit

now it really does not have to be this perfect, but its only a few minutes extra per

bracket

Yeah - that is the way to do it.  I have a box of different size centre drills depending on the final hole size.

 

But since I don't have any NC malarky and only have a precision drill press it is important to mark the hole centres accurately.  I use a digital height gauge with hardened spur to scribe lines in precisely the right place.  I then use a magnifying glass to get a centrepunch right on the scribe marks.  Then the centre drill and final drill size.

 

Time consuming, but it sure is nice when everything fits together just right.

[nopants]

Damn I feel like I'm in the stone age with my non-spring centre punch and hammer, with which I also get questionable results

[johnwmclean]

Thanks for the tips guys, I had time today to work on these brackets.

Punching and using a centre drill bit worked a treat, as well as leaving the jig floating on the drill press, this also saved a crap load set-up time between holes.

They’re fairly accurate... I’ve accounted for some margin off movement with the panels CamExpert are fabbing, but I won’t know for sure until I do a final fit.

 

[wink]

Just imagine if all those holes were 2mm out.......    

[DefQon]

Where does one go with the not so cheap route and obtain a fabricated L plate with TO-3 transistor template holes cut out? Almost a dozen on each side and I think its a painstaking process if I did it with the drill press. 

[n_maher]

I'd try these guys - http://www.cam-expert.com/.

[PretentiousFood]

Any recommendations for a nicer soldering station that's not quite as pricy as the Oki stuff? My damaged his Hakko 936, and his birthday is coming up.

[Pars]

Damaged in what way? One of my cats chewed through the cord on mine, and the rep sent me a new one free of charge. Since you are in Canada, that might not be an option though...

[PretentiousFood]

Damaged in an embarrassing way is all I know for sure. I think he was soldering a live circuit, and it shorted through the iron. I haven't used it, but he says the temperature has been unreliable since. It's also certainly no longer under warranty-- he modded it to install LEDs, so that he wouldn't forget to turn it off.

 

 

(The dead batteries are to keep the sponge moist.)

[mwl168]

Has anyone purchased hard-to-find transistors from pacificsemi in Vancouver Canada before? Are they reliable?

Looking to buy a few pairs of 2SK216/2SJ79. Found them at BDent and pacificsemi. BDent price is 50% higher than that of pacificsemi.

Thanks!

[luvdunhill]

The question really is, do you have a way to verify the devices and what is the return policy?

[G600]

Not exactly part sourcing, but I need an advice.

 

I'm planning to put my DAC in a case, but it's using an old fat EI-core transformer.

I would like to take the 2-boxes way, but where am I putting the PS boards and chokes ? Boxed with the transformer, or with the signal stuff ?

I read that chokes are sensitive to EMI...

I'm looking to keep the PSU's impedance as low as possible.

 

Any idea ?

Edited May 14, 2015 by G600