how to on louvers?

[ChuckD]

I'm not sure this belongs here, but, here it goes.
How would a guy go about making louvers by hand? This is a learning exercise, so I would like to try this with the minimum of tools, if possible!
I was thinking
1st: carefully cut slit with grinder.
2nd: shape louver against dolly with hammer.
3rd: planish with slapper.
Or
Build a hammer form?

Any thoughts, ideas, opinions, techniques appreciated!
Thanks, Chuck

[anders nørgaard]

Chuck,

I'd build a hammerform/louver die. If you slit with a grinder, the gap in the louver will be way to wide :!:

Anders DK

[ralph]

Chuck,
There is a great discussion on low buck louver tools here:
http://www.metalmeet.com/forum/viewtopic.php?t=222&start=0

Also Mike Rouse has some great pictures from his louver die and press build beginning at the bottom on page 3 of his gallery album here
http://www.metalmeet.com/photopost/showgallery.php?cat=500&si=&page=3&sort=1&perpage= 20&password=&ppuser=56&what=&name=&=

You'll find a lot more discussion and pics by doing a search on louver in both the forum and the gallery :idea:

[ChuckD]

Thanks guys.
I see I over simplified the process a little! :shock: I was "hoping" there was a method where a guy could do this with simple hand tools and simple hard work(my project only has 3 louvers).
The links Ralph posted has given me some ideas though.
Thanks again, Chuck

[Gene_Olson]

Chuck,

Of course there is, but it would involve specially shaped hammers, stakes, maybe a hammerform and a lot of practice with them before you start on the panel. :twisted:

Once you get the first one done the other two will be harder, at least they will be if all three are supposed to be the same.

I would guess that you could use a slitting chisel sharpened on one side for the cut.

I would not be surprized to find that a simple jig exists. Look at the way the Pakistani metalshapers make hinges, I used to think that was something that had to be done in a big hydraulic press with thousands of dollars in tooling.

I would bet on a small hammerform with a simple half oval punch and a bit of gentle persuasion.


Gene.

[Gene_Olson]

of course on the other hand if what you want to do is put shark gills on the side of your fairing (to facilitate airflow to the cyl heads of course) Then hand cutting louvers in a curved surface would probably be just the ticket.

http://www.metalmeet.com/photopost/data/3497/320outside2.jpg (http://www.metalmeet.com/photopost/showgallery.php?cat=3497)

These were cut with a slitting chisel on a lead block and formed with a sheepsfoot shaped tool like Chase #0302 on this page
http://www.chriswilsonstudios.com/thestore.html
except a lot bigger.

if you were doing a bunch of them it would be better to cut a wood or aluminum form instead of the lead.

Total time including shaping the unhardened tool and sharpening my chisel was about 20 - 30 min.

Gene

[Prostreet]

Hi Guys
Boy is this a post For Stan Lobitz . Look in his gallery I think there are some photo's there. I think Stan has made every louver there is to be made . :D :D :D :D
Steve

[Gene_Olson]

I think these pic's that Wray posted are some of the ones you mean?
http://www.metalmeet.com/forum/viewtopic.php?p=765#765

G.

[Prostreet]

Hi Guys
Thanks Gene those are the ones I almost forgot you've hammerd out quite a few by hand your self . :lol: :lol: :lol:
Steve

[ChuckD]

Gene,
Shark gills!, learned something new today, thanks. Thats exactly what I was thinking, 3 to 4 louvers on a cycle fairing. They'll be on a curved surface, approximately 3" - 4" in length and roughly 2" or so apart. I'm still working on the specifics on that one.
The sheepsfoot tool is a nifty solution as well, I could probably grind one out of an large punch or large bar stock? Just a thought!
Do shark gills get progressively larger as in your picture( I like it!)? I'm not to sure what a slitting chisel is though? Is it similar to a carpenters mortising chisel?
Thanks for the help, it's much appreciated.
Chuck

[CCWKen]

Another tip; if you have the roller dies, make the slit first then go back and roll the louver. I found that trying to slit and roll the louver in one step gives a wavy crown.

Apparently, the louver porton starts to stretch the metal too close behind the slit. Set the dies to slit and off-set the cut by just about 2X metal thickness. This will also act as a guide for the louvering pass and die will just bend the shape.

Also; Start inboard of the slit start and roll back to the beginning. Continue forward to the end of the louver.

[Gene_Olson]

Gene,

The sheepsfoot tool is a nifty solution as well, I could probably grind one out of an large punch or large bar stock? Just a thought!
Do shark gills get progressively larger as in your picture( I like it!)? I'm not to sure what a slitting chisel is though? Is it similar to a carpenters mortising chisel?
Thanks for the help, it's much appreciated.
Chuck
Bar stock would work fine for a more than 3 louvers :)
An old punch would give you a tool that probably won't ever need to be redressed.
A slitting chisel is just a thin chisel that has a curved edge. That is the center of the chisel touches the metal first. The outside ends are off the surface.
In this case I used one that had one flat side and a tapered face with the tapered side toward the louver. I cut from the back of the panel.