[TheForge] Nazel 4b

[Cameron Stoker]

I work in the same shop with Helmut, and use his Chinese hammer quite a 
bit. I'm curious what they mean by double oiling system. The hammer in 
question does have a double valve 'pneumatic oil pump' with a separate 
hose for the drive & work cylinders - I guess that could be a double 
system. The issue with it is that the check valves that keep the 
lubricant from slipping back down the tubes don't check. You have to 
prime the oilers every start-up or it just lubes with air for the first 
20 minutes. The other issue with it, is that the oiler box vibrates 
loose every two to three weeks. The bondo beneath the mounting bolt 
bosses crumbles out and the loose-tolerance bolts don't play well with 
locktite.

We've been meaning to replace the sloppy check valves with some little 
viton-seal plastic ones, but haven't gotten around to it yet.

The other lubrication issue is that the feel of the hammer is coupled 
with the oil viscosity and temperature. You have to adjust the amount of 
wd-40 and warm-up time for the type of forging you want to do. Hot & 
thin oil give you hard, fast and wild blows - cool and thick oil gives 
more precise blows for small stock, but lacks a lot of the oomph. We've 
learned how to deal with this over the last two years, but it's always a 
fiddly process.

After having used this hammer for about two years, I'd really look at 
acquiring and rebuilding an old piece of nazel or chambersburg iron if 
the prices were within the same ballpark. Of course, the machine work on 
a #300 hammer can easily run $15000 if it needs much.



Justin Fellenz wrote:
> Huh. The striker adveises a "double oiling" system, whatever that is,
> so it indicates they realize it's an issue. Were the problems your
> friend ran into lubrication issues, or something else?
> 
> J
> 

-- 
		Cameron Stoker
		Cameron at stoker.net
		"May you run like a vicuna!"
		pgp key: http://keys.stoker.net