No competition, why only HWlabs?

[BaThMaN]

ok then... how much you guys are willing to pay and what dimensions you would prefer??

[pHaestus]

If you are going to make double or triple thickness cores then do two things: (1) Make the fins more widely spaced and (2) offset the fins.

You know how this works; people will be willing to pay exactly what they would for a heatercore ($20 or so)

lol

[AngryAlpaca]

People are willing to pay much more if there are proper sized barbs and a shroud. You could do $30 without much loss of sales. I think your cooler may be too large, as well. We want good, compact, cheap, pretty, easy, and quiet. Got it?

[Butcher]

My current heatercore cost £5 (about $8) from a scrap dealer, can you beat that?

[BillA]

not as long as your MTBF is 'unknown'
mfgrs can't play that game, "Sorry" won't cut it

[Razor6]

I think $40 is a good price for a large rad but $50 or $60 seems more reasonable for that huge thing that was posted. I don't understand this talk of rows in relation to heater cores though, I thought that most heater cores were single row with 1 or 2 passes. What distinguishes the rows, pics?

[Les]

Originally Posted by Cathar

and had a fin density around 10-12FPI with ~8mm or so spacing between the tubes would likely perform quite a deal better than a .

How thick the fins?
Suggest that 30FPI x 0.1 fins would be superior - 8 mm between tubes

[psychofunk]

Can you guys post some pics of a rad that fits your descriptions. I think that what you guys are saying is that with someone like myself who uses very weak fans (the super low noise papst fans) would see better performance from a 1 inch thick core as opposed to a 2 inch core, assuming that...????....it has a larger frontal area.....what else please elaborate I cannot visuallize what you guys are saying.

I am very interested in this as I have been mulling over the idea of making a plexi box under my cube case (13x17x5) to act as a shroud for a couple of rads. Air would enter through the sides, pass through the rad up into the case where it would be exhausted from the top and if I am even in the ballpark of understanding what you guys are saying then a very large but very thin rad would work perfectly. Are there any rads that you guys can recommend? Or any bad things that you see in what I am considering?

[Cathar]

Originally Posted by Les

How thick the fins?
Suggest that 30FPI x 0.1 fins would be superior - 8 mm between tubes

30FPI is pretty restrictive if the fins are crenulated like I'm imagining they are.

The Nippon-Denso cores which are prevalent here in Oz have the fins cut and crenulated as well, so even though the metal is 0.1mm or so thick, the fin's cross-section is more like 0.3-0.4mm thick.

At really low air velocities through the fins the air tends to turbulate well enough for even fairly open FPI's to keep radiator efficiency high.

If the fins were just basic flat folds, then yeah - maybe a higher FPI. Would need to keep on eye on the pressure drop though.

[BaThMaN]

i'll let the scanned pics do the talking:


thats how the fins scales to axp tbredB...

estimated costs would be around $30-40 for 120x120mm single row single pass... my main concern is how will i ship it there? (from philippines)... im afraid shipping it there would cost more

[Les]

Originally Posted by Cathar

.

If the fins were just basic flat folds, then yeah - maybe a higher FPI. Would need to keep on eye on the pressure drop though.

Kryotherm suggests for a 240x120x12.5mm design:
3.7Pa @ 1m^3/min .
h(conv) ~133w/m^2*c and finning efficiency ~80% with 8 tubes

Edit: Finning efficiency ~ 15% with 1 tube

[AngryAlpaca]

Picture's a bit dark (looks pure black at first glance, pure black with some really dark gray if I squint) $30 isn't too bad, and I'd imagine that with the cheapest shipping you could get it to the US (get a retailer there so you're shipping bulk) it would only be 1 or 2 dollars a piece. I think it would sell ok, but it wouldn't be a top seller. IT MUST HAVE A SHROUD THAT ALLOWS EASY FAN MOUNTING. This would be better than the 120mm rad at Dtek, as it would be about the same price (maybe less as the shroud prices from them are ridiculous) and easier to fit/work with.

[Silent Bob]

Originally Posted by pHaestus

If you are going to make double or triple thickness cores then do two things: (1) Make the fins more widely spaced and (2) offset the fins.

You know how this works; people will be willing to pay exactly what they would for a heatercore ($20 or so)

lol

Like this?

These are made by some italian guys at http://www.air-xforce.com/
I first saw these rads about 6 months ago when they were just propotypes. I remember it was either here at ProCooling or at OCF, but I just can´t find the thread now.

Anyway, these have been designed especially for low powered fans. They also have some flowrate results with various pumps and hose size.

linky stuff:
Homepage
Description
Review

They cost roughly as much as the Black Ice here in Europe. But so far, I´ve only seen them available in Italy. But they must not have much success in sales, since they are using 1/2" nipples instead of the 1/4" threads used around here.

[BillA]

SB
interesting links, gonna have to get one of these to test
-> anyone in Italy I can paypal with ?

specifics lacking on testing, which may have been designed to produce those results
(at least I understand how they could have been different, was the other testing even done ? who knows)

[Cathar]

Originally Posted by Les

Kryotherm suggests for a 240x120x12.5mm design:
3.7Pa @ 1m^3/min .
h(conv) ~133w/m^2*c and finning efficiency ~80% with 8 tubes

Edit: Finning efficiency ~ 15% with 1 tube

Was not so much relying on Kryotherm for the suggestion. Pressure-drop seems too low for 30FPI based on Bill's real-world data.

Extrapolating from BillA's Thermochill 120.2 results offering ~10Pa of air-flow resistance at 1.0m³/min. The Thermochills have 24FPI. Even if we made the radiator single row and half as thick, at best we're still looking at ~5Pa at 24FPI, and surely somewhat higher at 30FPI.

I was thinking of optimising around the Papst 4412FGL, say at 75m³/hr, or 1.25m³/min, which that fan will push against ~5Pa. If we do some very rough extrapolation from BillA's data, for a 150x150x16mm core we're talking about ~8Pa of resistance at 1.25m³/min for a 24FPI core of that size, hence my thought to halve the FPI to ~12FPI as well.

Maybe you could run that through the finning efficiency calculator... I suspect upon revising my thoughts that perhaps the best FPI may lie more at 16FPI or so, or at least there is enough of a flow vs pressure vs finning performance tradeoff "plateau" that perhaps anything between 10 to 30FPI is acceptable.

[Edit: Bah - had misread flow charts on Papst datasheets - revised statements]

[Cathar]

Something like SilentBob linked to above would be perfect. It is pretty much exactly what I'm talking about, onlythose rads are twice as thick as I would propose. If those rads could be made single-pass and 150x150mm in size, and half as thick, then that would be perfect. They appear to be using ~12FPI like I mentioned, and the same sorts of tube numbers. I suspect that these guys made theirs for fans still slightly more powerful than the Papst FGL's though.

[j813]

What if we make it larger?
About similar to a small car's Radiator dimensions, the fan could be same as with a car's? Exaggerated?

[psychofunk]

Originally Posted by Cathar

Something like SilentBob linked to above would be perfect. It is pretty much exactly what I'm talking about, onlythose rads are twice as thick as I would propose. If those rads could be made single-pass and 150x150mm in size, and half as thick, then that would be perfect. They appear to be using ~12FPI like I mentioned, and the same sorts of tube numbers. I suspect that these guys made theirs for fans still slightly more powerful than the Papst FGL's though.

These are exactly the fans I use and all the good sounding stuff that you guys are saying makes my head hurt. Please Cathar, in lamans terms if I am using these fans then I should be using a thinner core then the 2 incher I am using now. Or is it just that I would be using the cooling ability more effeciently? Hell I will mod the heartercore to single pass if that helps as I have already done that with my caprice core. I have been looking at using (2) 2001-2002 Oldsmobile Aurora Heatercore. Help I dropped my books and I can't get up!!!!!

[Gooserider]

Hmmm.... In my brute force DIY setup I'm using a 2-342 single pass GM heatercore, which I've always thought was supposed to be the hot setup, even with axial fans (2 X 120mm, chosen for good SP #'s, but will be undervolting to reduce noise).

Judging by the stampings on the sides of the core, and what I see trying to look into the fins, it appears to be usin two layers of tubes, which are not staggered. There are 13 sets of tubes accross the 6" core width for a space between the tubes of ~ 0.5" or 12mm The fins between the tubes are thin sheets of folded copper, which appear to be sliced across (perpendicular to the airflow) about every 0.1" or so giving some trubulence, but not greatly increasing the thickness of the fin. There are about 10-11 fins per inch, not staggered that I can see (I can easily look through the core when it is at right angles to my sight)

The core is about 2" thick.

Aside from the thickness, this seems to match Cathar's hypothetical description fairly well, with the thickness partly compensated for (how much?) by the slightly wider tube spacing, and the low end fin spacing.

Something like a 15x15cm cored area heater-core, that was single-row (~ 1/2" to 5/8" thick), with a nice 10-15 degree angled shroud leading into the 12cm low-speed fan that is pulling, and had a fin density around 10-12FPI with ~8mm or so spacing between the tubes would likely perform quite a deal better than a BIX when matched with the same fan.

Now for the interesting hypothetical questions....

1. Would a heater core such as I am describing benefit by cutting out part of the fins so that at least part of the depth consisted of just the bare tubes?

2. If so, how much of the finning should be removed?

3. Would it be better if the fins were removed from just one side (if so intake or exhaust side?) or approx equal amounts from each side? (I would tend to think the latter so that each row of tubes would be left with at least some fin coverage...)

4. Given typical core construction, can this be done without reducing the structural integrety of the tubes?

5. Assuming the primary concern was to reduce noise,, with maximum cooling a secondary concern, would the effort be worth it? How much would it be possible to reduce the fan speed w/o seriously hurting the cooling or how much would the cooling be reduced (if at all) at a given fan speed?

Obviously since this is a hypothetical question, exact answers aren't possible or expected, but does the theory point to any useful conclusions?

Gooserider

[nightic]

Originally Posted by Silent Bob

...These are made by some italian guys at http://www.air-xforce.com/
I first saw these rads about 6 months ago when they were just propotypes. I remember it was either here at ProCooling or at OCF, but I just can´t find the thread now.

Anyway, these have been designed especially for low powered fans. They also have some flowrate results with various pumps and hose size.

They cost roughly as much as the Black Ice here in Europe. But so far, I´ve only seen them available in Italy. But they must not have much success in sales, since they are using 1/2" nipples instead of the 1/4" threads used around here.

Just try buying one, that's when the fun starts.

[BillA]

what is it in the Italian egocentric view of the universe that leads them to the conclusion that businesses outside of Italy shut down for August ?

or perhaps to reduce their order backlog ?
we had the same with that Italian pump mfgr, strange

[Cathar]

I hunted down a nice radiator today, known as a "Honda P60".

Core area is essentially:

24cm x 30cm x 25mm (9.5" x 12" x 1"). Has 16FPI, red-brass w/ copper-fins. Dual-row core, but due to the lowish FPI and thin-ness, very, very open air-flow design.

I'm getting them to customise it into a single-pass configuration with 1/2" copper-pipe fittings, and will be picking it up on Monday.

Regarding cores like the ones that the Italians were showing with that flat-fin rather than fold-fin style, they had these available there but not in thin sizes, but could get them custom made up to order if so desired. Both of the cores I saw were 4-row cores with the rows staggered, so not exactly free-air-flowing. I asked about getting them done in a single or two-row format and with parallel rows and he seemed to reckon that it could be done. Those type of cores, so he explained, were not manufactured on the huge mass-production run machines, and so while being a little more expensive, were more easy to obtain in a custom configuration in smaller batches. I tried to press him for more information about it, but he's just a retail outlet so I could chase it up further with the core manufacturer if so inclined.

Anyways, this new radiator should mean that I can gid rid of this pair of ~35dBA fans I'm using presently and move to lower noise fans with no real performance loss.

[psychofunk]

Cathar could you possilbly post some more info, I would like to try and find this rad here in the states. Please post any info that you think would be helpful. I tried searching for honda p60 but got nothing.

[Cathar]

Originally Posted by psychofunk

Cathar could you possilbly post some more info, I would like to try and find this rad here in the states. Please post any info that you think would be helpful. I tried searching for honda p60 but got nothing.

Friday night here now. When I go to pick it up I'll get some more info on it.

[aaronspink]

Originally Posted by Cathar

Friday night here now. When I go to pick it up I'll get some more info on it.

What's the price range for it?