Grinding machine – SV
Scope of application and advantages of the grinding machine
The MASS SV 200 WV grinder removes excess plugging paste from printed circuit boards and inner layers after the via hole filling process. In this way, a flat and uniform surface is achieved on the printed circuit board. The grinding wheel is driven by a variable speed servo motor. The result is a uniform surface with fine structure. This excellent grinding result is achieved by the pressure-controlled rotation and the manual movement of the grinding head in combination with the linear guides and the adjustable grinding pressure. This also minimizes the risk of possible grinding through of the copper foil.
The grinding machine for the manufacture of printed circuit boards is used in the following cases
- Deburring and grinding of drill holes in rigid printed circuit boards
- Grinding after electroplating
- Grinding after the conductive layout buildup
- Cleaning and grinding of press plates
Function and structure of the grinding machine
The inner layer of the printed circuit board is held on the aluminum work plate by a rubber mat. The work area is protected by safety glass. The grinding head can be adjusted with a setting accuracy: 0.22 μm can be lowered onto the printed circuit board. The movement of the grinding head in X-Y direction over the PCB is done manually by hand. The cooling water is delivered to the grinding head via a pump. The coolant is filtered by a belt filter installed at the bottom of the machine frame. Optional delivery with vacuum pump for thin or warped panels.
- Dimensions: Length 1,400 mm, width 1,100 mm and height 1,700 mm
- Max. PCB format: 915 x 610 mm
- Speed: adjustable 1000, 2000, 3000 rpm
- Connection: 400 V, 3 P, 50 Hz, 5 kW
Power squeegee – PS
Scope of application and advantages of the hand tool for handling printed circuit boards
The Power Squeegee hand tool was developed by MASS to fill through holes in printed circuit boards. Silver paste (conductive), copper paste (conductive) and epoxy fill (non-conductive) can be used with the Power Squeegee. The use of the Power Squeegee offers the following advantages:
- Partial plugging of holes
- No loss of the valuable silver paste
- No cleaning or decanting into storage containers necessary
- No direct contact between paste and compressed air
- At high pressure (approx. 3 bar), boreholes with large aspect ratio 1:30 can be filled safely
Function and structure of the hand tool for handling printed circuit boards
The paste is located inside the container and is pressed into the holes by means of compressed air via a diaphragm. The operation is carried out by means of a foot switch. Users use this to specifically control the pressure in order to precisely fill the bores. In one pass, the holes are filled and there is no risk of air bubbles remaining in the holes. The Power Squeegee should be stored in the refrigerator when finished to prevent the paste from drying out.
- Length: 110 mm
- Diameter: 65 mm
- Material: Stainless steel
- Weight: approx. 1200 g (including paste)
- Paste supply: 200 g (silver paste)
- Compressed air supply 6 bar, working pressure approx. 3 bar
External double-sided squegee device – ES
Scope of application and advantages of the squegee device for handling printed circuit boards
The ES external doctoring device from MASS can be used to squegee excess plugging paste from the PCB surface. For this purpose, the panel is hooked into the recess after plugging, and the automatic sequence is started by pressing a key. Driven by a servo motor, the device moves to the upper position when open and the pair of squeegees is closed there. When shutting down, both panel sides are simultaneously squegeed, always from top to bottom. The contact pressure of the squeegee is adjustable via a pressure regulator. The vertical movement is realized via two linear guides with frequency-controlled drive. From here the panel go to harden the paste. The squegee device is operated by means of a touch panel. The front area is monitored via a safety light grid.
- Dimensions: Length 630 mm, width 845 mm and height 2,067 mm
- PCB format: max. 610 x 762 mm / 24 x 30"
- Printed circuit board thickness: 0.4 - 8 mm
- Connection: 230 V, N, PE 0.3 kW
- PLC control: Siemens S7 300 with touch panel
Paste recycling system – PRS
Scope of application and advantages of the paste recycling system
With the PRS external paste recovery system from MASS, non-conductive pastes that are produced as excess during the via hole filling process and the squegee process are cleaned via a V2A filter. This offers the advantage that impurities are removed from the paste and the filtered paste can be used again.
The Paste Recycling System ensures that any excess paste produced is placed in a collection container. By switching a valve, a vacuum is created in the collection container and the paste runs through the V2A filter into the collection container. Once this process is complete, a second valve is switched to create negative pressure in the pre-assembled cartridge and fill it.
The vacuum in the collection container and in the cartridge removes air pockets in the paste (degassing). When the cartridge is full, it can be used again in the vacuum chamber plugging machine (VCP) or in the vacuum via hole filling machine (VHF).
- Dimensions: Length 300 mm x width 300 mm x height 1300 mm
- Filter for the paste: V2A, depending on paste 100 µm or 125 µm
- Compressed air: 6 bar
- Vacuum generation integrated
- Weight: approx. 40 kg
- Base frame: Stainless steel frame welded (V2A)
Cleaning unit – RE
Scope of application and advantages of the cleaning unit
This machine has been designed by MASS to clean the filling heads, attachments and tubing of the Via Hole Filling machines VCP and VHF. The base frame consists of a sturdy welded V2A frame, the outer panels are folded stainless steel V2A sheets. All plates open easily via single-key locks and can be removed or opened for accessibility. The system is designed so that all components are clearly arranged.
The filling head to be cleaned is inserted into the washing chamber and connected to the pressure port of the diaphragm pump. A cleaning process takes approx. 15 - 45 minutes, but depends on the plugging paste used. Butyl diglicol (BDG) is used as the cleaner. The diaphragm pump is switched on, the speed is preselected on the small handwheel.