8 Oct
2011
8 Oct
'11
10:57 a.m.
On 8 Oct 2011 at 20:27, Matti Nummi wrote:
Has anybody experience and instructions how to replace
aging and
breaking plastic parts. I would prefer replacement with metal parts
not to repeat the problem later. The problem is in parts like sledges
etc. but not in running mechanics.
I sure others will have lots of advice, but speaking from my own
experience, if the part has any level of detail, I like working in
brass. Brass is relatively strong, non-magnetic, ductile, easy to
machine, can be soft-or-hard ("brazed") soldered and will take a high
polish and will naturally form a film of protective oxidation over
time. It's comparatively expensive, but how much are you going to
use? There are many alloys, some of which are easier to work with
than others, so pick your stock carefully.
I've made replacement parts for disk drives (one is a part on the
latch mechanism for Tandon TM-100 disk drives that seems to break
frequently.)
Where mechanical strength matters, mild steel is just about the only
practical alternative. If I need a flat plate of some sort, aluminum
is always an option.
But don't discard the idea of plastics entirely. Acrylics machine
very well and will take paint readily. Polyester casting resin can
be used to duplicate parts that can be expressed as a moldable shape.
To do any job well, the proper tools are a necessity. Be prepared
for some sweaty-palms dry-mouth moments. Even used quality machine
tools aren't cheap.
--Chuck