Brass

[Etacovda]

Can anyone tell me what the difference is in regards to machining vs copper? my drill press really doesnt handle copper when i get to 15mm diameter; will brass be a lot easier to drill, or worse? What alternative metals would suit the top of a block that would be easier to work with? I'd prefer to stay with metals that i can solder together, as these are obviously home made blocks.

Its been ages since ive even touched brass, barring barbs...

Apologies for my newbieness, quite tired at the moment.

[DeadEye]

IMHO brass is much easier to machine using any workshop methods.

[8-Ball]

Brass is significantly easier to machine than copper and should not pose any issues with galvanic corrosion.

It pretty much is the best option really.

8-ball

[kronchev]

it doesnt conduct heat as well does it?

[8-Ball]

No, but that doesn't really matter if he's using it for the top of the block.

I wouldn't recommend it for the whole block.

8-ball

[killernoodle]

It has been used for a base before, but it didnt turn out well. The only problem with brass is that it is fugly and reminds me of a 1800s steam engine too much. //weird

[SlaterSpeed]

Its easyer but not easy. It snatches very easly when you are drilling so be careful.

[JFettig]

I almost prefer machining brass over aluminum. its good stuff. It doesnt get stuck to cutting tools like aluminum does. The only downside to brass is that its just a little more expencive. I hope to get some soon.


Jon

[SlaterSpeed]

Yeh, I think if i ever end up making a block for sale it will be at the top of my list. Personaly i dont see any problems with aluminium but some people are relly paranoid that its going to corrode so its worth that extra outlay to gain those extra customers. Also i like having the option of soldering my blocks beacuse some are so small (mosfet etc.) that bolts would have to be stupidly small to fit.

[Etacovda]

Excellent, thanks guys the cheap drill press really doesnt like copper at 15mm diameter, takes around 10 minutes to get through 10mm of material - it grabs, it sticks, its plain annoying, even with water and/or cutting fluid - I think I'll try the brass route.

[jaydee]

Brass is good. It was designed to be machineable. There is some variances in quality (at least in the stuff we used at our shop) but over all much easier to machine than copper and even aluminum (used all three almost every day). I actually like the looks of brass when it is all polished up. But this comes from someone who worked with it for 14 months strait and at an engraving shop.

[j813]

Is it lighter than Cu?
I don't have too many Cu and Brass here to compare both.

[Etacovda]

Yeah, im partial to the look of brass as well - it looks very nice with polished brass barbs. I priced up some brass, doesnt look too expensive - its such a pity, i scored so much copper so cheaply at a scrap yard, but i guess ill just have to make more blocks, haha I managed to get 2500mm x 50mm x 9.52mm for 55nzd - about 30usd! There will be a few blocks made out of this stuff - 12 brass tops, cut to size have been priced at $10nz each, or about $6usd - total of 120nzd. Im going to look into getting them at half that thickness as well, I want to make this design somewhat more efficient.

[Butcher]

Originally Posted by j813

Is it lighter than Cu?
I don't have too many Cu and Brass here to compare both.

Standard yellow brass (C270) has a denisty of 8.47g/cc. C110 Copper is 8.9g/cc, so yes brass is lighter than copper, but not much.

[zer0signal667]

70/30 Brass also has a thermal conductivity of only 110 W/m-K, roughly 25% of that of pure Copper. I wouldn't use this stuff as a base material...

[Etacovda]

Im not, if you read my orginal post Its purely for the top, for machining purposes.

[zer0signal667]

Originally Posted by Etacovda

Im not, if you read my orginal post Its purely for the top, for machining purposes.

Yah I noticed that, but it in your last post it seemed like you were going to use it for base material too.
There is the possibility of brass dezincification, though. I'm no corrosion expert so I'm not sure how likely it is, but keep it in mind. Basically it's the removal of zinc from a brass alloy, leaving behind a porous copper piece. It can cause your brass to turn into a copper sponge and leak throgh the pores.


Conditions favoring dezincification are contact with slightly acid or alkaline water. Not highly aerated, low rates of flow of the circulating liquid, relatively high tube-wall temperatures and permeable deposits or coatings over the tube surface.

[Taken from http://www.corrosion-doctors.org/Forms/dezinc.htm]

[Etacovda]

hmmm thats not very good then... has anyone experienced this before? I originally got the idea from looking at a silverprop block, but it could well have been a plating; I didnt check.

The water will probably be slightly alkaline in a loop wont it? I'm looking at zero aeration (obviously) and flow rates which I would consider high (1.3-1.5 gpm)

When thinking about it, SURELY it wont be a problem.... we all use brass barbs, do we not? my heatercore has brass ends...

Can anyone elaborate and confirm?

[Incoherent]

Originally Posted by Etacovda

hmmm thats not very good then... has anyone experienced this before?

Yes, but not in this application.
A gate valve in the salt water cooling inlet for the A/C system on a 130' boat. The shipyard had connected stainless steel pipes to the manifold via this valve.
A very interesting and potentially ship-sinking effect. The brass was porous, leaking like a sieve.
I'd say it would rarely if ever happen in a waterblock.

[Etacovda]

Thats pretty mad, but as you say, I doubt it will happen in a waterblock situation.

Thanks for that - you learn something new every day.

[Butcher]

Given brass is commonly used in heater cores and car radiators, and they run a similar cooling solution to water coolers, I don't think it'll be too much of an issue.

[Etacovda]

Well, i used brass (got a hell of a lot of splinters, and invested in some decent work gloves, lol) and i have to say, getting a mirror shine is so much easier....

Feel free to ignore the Ralph magazine, or look at the chick instead of the blocks

[PrinceXXX]

looks real nice and shiny that does etacovda. I gather you made the same design with this block as the other one featured in your ghetto setup? Where did you get the parts for this (namely the hex screw bolts and the brass)?

[JFettig]

so how did you like your brass? I did some machining of some brass on my cnc the other day and I was amased!!! its some sweet stuff! for that reason I would use brass for tops regaurdless, it is more expencive but who cares, it cuts faster and in machining Time=Money


Jon

[Etacovda]

PrinceXXX - no, this block is a hybrid block; think TDX, whitewater, lumpychannel and some personal 'twists' to the design.

Jfettig - brass is awesome. I wouldnt use anything else; the finish is SUPERB (flat mirror is very easy to obtain; I just buff them though, generally), and im really happy with the aesthetic of the blocks.