Re: Water Jet

Most industrial watercutting machines that cut any steel are 30,000 to
50,000 PSI.
You could probably cut balsa wood with no problems with apressure of
2000-3000 PSI.

I have thought quite a bit about such a machine but they are too large, to
noisey and don't lend themselves to the home shop.
Dan
-----Original Message-----
From: Don Hughes <pencad@...>
To: CAD_CAM_EDM_DRO@onelist.com <CAD_CAM_EDM_DRO@onelist.com>
Date: Sunday, August 08, 1999 11:43 AM
Subject: Re: [CAD_CAM_EDM_DRO] Water Jet

>From: Don Hughes <pencad@...>
>
>
>
>>
>> You are thinking heavy industrial. I have more in mind a small hobby

unit.

>> My idea is much like Mario in that I want to cut things like balsa upto
>> 3/16" and maybe carbon laminates up to .020".
>
>When I was still in the machine shop as a shop foreman, in our CNC dept.
>we had a water jet that we used for mainly cutting 6" die steel and
>nylatron. We would on occasion have a customer want some non-ferrous
>cut, such as wood, but we found that the water spray left too much
>residual water on the surface and would soak the wood, as well as what
>seeped into the wood from cutting it.
>>
>> I have no clue what type of pressure or volume this would require. I

wonder

>> if good pressure washer with a 0 deg nozzle would be enough? I somewhere
>> remember reading that they use a polymer additive in the water to reduce

the

>> divergence of the spray. Anyone know anything about this? Also, I am not
>> quite sure if cutting balsa how to support it? I imagine that you need to
>> have no obstructions under the material being cut in the path of the

water

>> stream?
>
>Please don't quote me here, but I will take my best shot at it. If
>memory serves me right we used a two-stage compressor for the water
>pressure. The first stage built the pressure to 1000 psi. and the next
>stage took it to I believe 3000 psi(and here I could be very off base)
>at the cutting tip. Our tips were ceramic because of the sand used in
>the water. Now that I have mentioned sand, it gets all over the place,
>in the air, on the controllers, and the bed of the machine has to be
>cleaned out every month. On our machine we had a 1/8" wide x 4" tall
>grid work that all materials rested upon to be cut. These had to be
>replaced as well as the jet would eventually cut away the steel bed and
>not have too flat a surface anymore. The next area of concern came in
>trying to keep the rails of the machine clean. The sand would get into
>the Thompson bearing and just literally tear them apart, and we had
>covers on all the rails, the sand will get everywhere. We also had a bit
>of a problem in keeping all the wiring dry near the cutting tip for the
>controls. This is some of the trials and tribulations that I encountered
>with the waterjet. Overall for what we did with it, it was a great
>workhorse for us and was running 20 hours a day. Another thing we had to
>contend with was the noise. Our machine was very noisy for the other
>shop members.
>
>I cut balsa wood myself, and I have decided to go with a CO2 laser as it
>will vaporize and not saturate the wood. Balsa has different densities
>and if it is of the lighter density, will absorb most of the water
>applied to it and warp. I did not want this.
>
>Hope this helps,
>
>Don Hughes
>
>>
>> More things to play with and no time.
>
>Don Hughes
>
>--------------------------- ONElist Sponsor ----------------------------
>
>GET WHAT YOU DESERVE! A NextCard Platinum VISA: DOUBLE Rewards points,
> NO annual fee & rates as low as 9.9 percent FIXED APR.
>Apply online today! http://www.onelist.com/ad/nextcard1
>
>------------------------------------------------------------------------
>Welcome to CAD_CAM_EDM_DRO@...,an unmodulated list for the

discussion of shop built systems in the above catagories.

>To Unsubscribe, read archives, change to or from digest.
>Go to: http://www.onelist.com/isregistered.cgi
>Log on, and you will go to Member Center, and you can make changes there.
>bill,
>List Manager
>