THE REQUEST: I have a number of working qrp rigs, both homebrew and made from kits. They could do with the finishing touches to their aluminium (aluminum) panels and cases. My question is, does anyone on the list have a pet way to make 'em look beautiful? Maybe there's a method which does not use paint or other special treatment. I'm sure this must be a much asked question, and information on how best to do this will likely be of use to others reading this. Hope someone can suggest something really neat! I'm all ears. AND NOW, THE ANSWERS! Regards to all.....72/73 Brian g3mbn From: "Peter Vaughan"Thanks for the above ideas to those who contributed.
The following is the way I finish my front panels thought it may be of some help. 1. Try to make the front panel detachable if possible, this makes any artwork easier to apply. 2. Apply spray paint primer, white primer for a white finish or grey if a dark finish is required. Apply sparingly repeating coats at fifteen minute intervals. When the panel is covered allow to dry thoroughly rub down with fine wet and dry paper and wash with soapy water. 3 Apply finished colour as above, if the finished panel is to be black or white matt spray paints are available from car accessory shops. When finished use cutting polish 'Tcut', 'Brasso' etc to provide a smooth surface to apply artwork 4. Apply rub down lettering is available at all good art shops, I use 2.5mm high 'Decadry' lettering which is available in both black and white for about £1.50 a sheet. I have also used 'Lettraset' lettering but this is expensive as the sheet size is larger. Be patient when applying lettering any mistakes can be removed using a sharp scalpel. To ensure lettering is straight fine pencil lines can be used these can be removed following completion. 5. If lines are required on the panel, e.g. RIT and Vol indication I use a 'Rotring' lining pen 0.7mm dia. Rotring ink is available in both black and white. 6. When artwork is complete it can be sealed using clear lacquer, again available car accessory shops. Again be patient applying several thin coats. A word of warning, test the lacquer with the lettering I once used some lettering that reacted with the lacquer turning the lettering to liquid! 7. When complete the lacquer can be polished to a gloss finish using cutting polish. What you will end up with is a hard wearing panel and although time consuming it is well worth it giving a professional finish providing the process is not rushed. Regards Peter G4TCQ Hi Brian: With regard to lettering of the panels I have had a good deal of success with the Brother P-Touch labelling system (not sure if you have them in the UK). Here in the USA the basic machine can be gotten for about $50 with a couple of tape cassettes. I use the clear tape for the lettering, which puts black letters against the panel surface. There is a choice of fonts and font sizes, so you can be a little creative. Perhaps the price for the machine is a little high for some, but I use it for other things too in my home office so that handles the expense side for me. Cheers! David Gwillim KB2TQX RE: Front Panes You would think someone out there would have made, perhaps they have, a clear sticky backed film for use with computer printers. For a long while A4 sheets of acetate have been available for use with Overhead Projectors (OHP's) and marker pens. They also come in versions which are heat tollerant for putting through photocopiers and laser printers, and there's a variant for inkjet printers (so the liquid ink doesn't run off!). Vinyl cutter printers attached to Pee Cee's use stock which is like sticky backed plastic. Perhaps someone knows of a source of this material which is clear and suits the range of printers out there? 73 All G0SBN / Glen / G-QRP 9024 I use a wire brush in an electric drill. This gives the soft aluminium surface a texture that does not show subsequent scraches. As to labelling the controls - this is still a problem. Dymo tape is OK for some things (but not tuning scales for example), but looks pretty naff! If you have the patience (and you'll need it) and have access to a PC with a simple drawing software package (or maybe even 'Word'), then the entire front panel can be designed and labled and printed out on to thin card. The tricky bit is getting the holes in the chassis to match up with the scales on the card if you do it in the wrong order! A few coats of varnish wil protetct it from dirt and damage, and then stick it onto the aluminium front face. If the surface was already treated as described above, Pritt Stick type glue is sufficiently strong to stick it on. If you then need to change it, it can be peeled off and any bits still adhereing can be removed with warm soapy water. Ian Liston-Smith G4JQT Labels: The materials and technique for making VuGraphs, (Overhead projection transparencies) may be adapted to Panel labels for rigs. This worked well for me with the small front and rear panels of the SST rig. I just made a vugraph on clear film, that makes the control words and symbols a colored ink, and then cut the vugraph panel to fit. The SST and Wilderness rigs use the Control hardware to hold the connectors and pots to the panel, thus you punch out holes for those shafts and connectors, and use the control and connector nuts to keep the plastic overlay against the metal. 72, Stuart K5KVH GQRP 4943 MS Paint, Word etc. will all produce the required text on coloured paper from a Laser or photo copier. This can be laminated with a clear and very tough plastic film by using overhead transparency sheets. Coat the transparency with white pva wood glue and apply to the printed sheet. The PVA dries clear, a little more applied to the laminated panel can also be used to glue it on. The sheet should glued on WITHOUT any holes cut. Once dry a scalpel will pierce any pot/mic hole etc. and allow a very clean cut to made around the circumference. Injets are not suitable for this application as both varnish and glue will cause the text to bleed. To give alloy cases a nice finish, with out the hassle of paint, use Fablon from your local DIY outlet. Fablon is a coloured plastic sheet (paper thickness) with a sticky back. Do not attempt to remove the carrier completely, instead just start a strip about 10-15mm wide and then place and peel. De GW8ELR Hi All, In my apprenticeship we used the following high tech method, to get that once popular circular effect on aluminium. Depending on the size of the circle you need, cut off a piece of dowel about two inches long, into one end cut a fine slit about one quarter of an inch deep, across the diameter, into this slit goes a flap of emery paper, use the grade of emery to suit the finish, the flap is folded across the dowel (rough outermost). The dowel is held in the chuck and lowered onto the panel. Experimentation on an offcut may be useful. Our panels were fixed to the bed of the machine and we could wind them across with the vernier adjustment for an even, accurate placing of the circles. Hope this helps. NC Allison When I visited the Grass Valley Group factory, in the days when they made video equipment with ''brushed aluminum'' panels, they simply fed the aluminum under a huge drum sander to get that 'brushed' look. Seems to me they made two passes, then they anodized the panels. Maybe for QRP you could just spray the sanded panel with clear flat Krylon. Another lo tech approach that gives a nice finish to take the finished panel to a shop that cleans spark plugs and use the glass-bead sand blasting machine they use for cleaning the insulators. Many operators will let you drop in during off hours and use the machine. This technique gives a very fine grained velvety look that takes rub down letters well. Overcoat with flat lacquer for durability. Bob Bruner WB4TAJ/9
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