Homebrew PCBs

It is hard to know the real amount. The spray etchers of that time only include some a few specifications.

The Kepro BTE-202 and BTE-201 used a Little Giant pump model CP-6500, Product #540004. That part is not manufactured anymore. It is replaced by model CP1-115.

The original CP-6500 has the following specifications:
PRODUCT #540004, MODEL CP-6500
FOR COOLERS UP TO 6500 C.F.M.
115v. 60 Hz, .85 amps, 1 PH

The new model available is:
PRODUCT #540005, MODEL CP1-115
1/70 HP, 115/127v., Capacity 307 GPH@1', 5000-7500 CFM

According to specifications and graph table (which appears in the Little Giant catalog) the newest pump moves about 300 Galons per hour, for a typical 50 cms of head above the sump of the etchant to the spray bars.

Those figure may be considered with care, since I remember that none of the spray etchers manufacturers specify that measure in their units.






--- In Homebrew_PCBs@yahoogroups.com, "Andrew Volk" <amvweb@...> wrote:
>
> What is the volume of etchant that has to be pumped, say in Gal/Min?
> 
>  
> 
> From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
> On Behalf Of jcarlosmor
> Sent: Monday, August 20, 2012 11:37 AM
> To: Homebrew_PCBs@yahoogroups.com
> Subject: [Homebrew_PCBs] Re: Kepro bench top spray ectcher
> 
>  
> 
>   
> 
> 
> Hello Tom,
> 
> Thank you very much for your detailed information. I agree with you that the
> pumps in this unit get damaged very soon, and need continous replacement.
> 
> Also, I am planning just to build a new spray etching tank form scratch. In
> the web there are some pages about that. I believe some detailed
> construction plans are in the "instructables" site, and some german web page
> also details construction, but for a central rotary spindler etch machine.
> 
> Most etching tanks of the 80s were made of PVC, but Polypropylene seems also
> a good choice now. ¿Does anyone knows if PP can be cemented, like PVC, and
> how well can whistand the FeCl and CuCl? Most PP tanks are welded instead.
> 
> The beauty of the old Kepro spray developers amd spray etching tanks was
> their simplicity. No sophisticated noozles, no adjusting pipes, etc. Just a
> tank with very simple spray bars, the mesh diffusers, and even at ambient
> temperature your double sided 12x12 inch PCB was ready in a less than five
> minutes.
> 
> Tom, some photos of your Kepro spray system also would be very helpful for
> everyone interested in building their own DIY spray etch. I understand that
> the construction of such device may not be worth the time and money for the
> ocassional DIY PCB maker with only a few PCBs per month, but if you have
> some space in your basement, and often you make PCBs in a regular basis, the
> addition of a spray etch system it would be very helpful.
> 
> Regards.
> 
> --- In Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com> , "twb8899" <twb8899@> wrote:
> >
> > In my last message I tried to show how the spray manifold drill pattern
> would look but it didn't post correctly. This time I'll add some hyphens so
> it spaces properly and I think you will get the idea.
> > 
> > -----------------------------------------------------
> > O------O------O------O------O------O------O------O
> > 
> > ---O------O------O------O------O------O------O
> > 
> > O------O------O------O------O------O------O------O
> > -----------------------------------------------------
> > 
> > If this doesn't post correctly I'll make a drawing or take some photos and
> post them later.
> > 
> > Tom
> > 
> > 
> > --- In Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com> , "jcarlosmor" <jcarlosmor@> wrote:
> > >
> > > 
> > > 
> > > 
> > > Hello Tom,
> > > 
> > > I had obtained a used Kepro bench-top etcher. It is a very old machine
> (mid-80s I believe), but I had seen those machines in action many years ago
> and the performance is outstanding for fast etching of batch PCBs.
> > > 
> > > The problem is that some parts are missing and/or require fixing. The
> two spray bars are lost. That is no problem because I can buy, cut, and
> cement 1/2" PVC as the originals manifolds. The problem is that I do not
> remember how many holes were in every spray bar. I remember that the hole
> size is about 1/16" ¿Am I correct?, since I used a drill bit of this size to
> clean of debris in the spray bars in those etchers many years ago. Do you
> recall how many holes, what distance between them, and the angle of up/down
> orientation in your Kepro etcher? I know that these details are very
> important to obtain the maximum performance of these units.
> > > 
> > > Thank you very much in advance for any help.
> > > 
> > > 
> > > 
> > > 
> > > --- In Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com> , "twb8899" <twb8899@> wrote:
> > > >
> > > > Grant,
> > > > 
> > > > You could try using one of the Little Giant pumps. I haven't bought 
> > > > one of these pumps in years but they used to cost about $25 from WW 
> > > > Grainger. Kepro uses this small pump in their etchers. They modify 
> > > > the pump by removing the metal impeller and installing one made from 
> > > > PVC plastic. There are two pumps in the machine, one for each side. 
> > > > The manifold is made from 1/2" CPVC pipe. The pipe has about twenty 
> > > > or so small holes drilled to give the spray pattern. A piece of 
> > > > plastic window screen hangs between the manifold (spray bar) and the 
> > > > part to be etched. This screen is used to disperse the spray pattern 
> > > > across the board for even etching. It works pretty good with 1 ounce 
> > > > copper taking about 4 minutes to etch with ferric chloride.
> > > > 
> > > > Tom
> > > >
> > >
> >
> 
> 
> 
> 
> 
> [Non-text portions of this message have been removed]
>