[Vince Koehn]

I am preparing to add the audio panel and SL40 to my panel and was wondering what the best way to cut the panel would be. When I made the panel I used a cutoff wheel to cut the avionics hole, but am a little nervous using a cutoff wheel on a finished-painted panel....one slip! My panel is powdercoated in a textured iron glimmer, so kinda hard to touch up with paint. Would a air saw work better, or is a cut off wheel the best option? Seems like a air saw would be a little more controllable.

 

[vlittle]

cutting panel

I used a sabre saw with a metal cutting blade. Lay down masking tape on the panel to protect the finish, make your marks on the tape.

Drill some holes with a step drill to allow you to insert the saw blade, and cut close to the lines. Finish with a file and remove the tape.

Carefully, with a paint brush, prime and paint the edges of the cutout.

It won't be perfect, but once the avionics are in place it should be ok.

Vern Little

 

[sf3543]

If it were me, I would not use anything that reciprocates to cut the panel, especially if it is already painted.
The method I would use is:
Mark and outline the area to be cut with tape. (Masking tape, etc.)
Drill the corners with a #40 or #30 drill bit, inside the corners.
Use a cutting wheel on a dremel or die grinder. I like to use the reinforced cut off discs for the dremel.
Carefully scribe along your line with the cut off, but do not cut all the way through the metal on the first pass. This will cut the paint and some of the metal. Use a second or third pass to cut through the metal completely. Be careful at the corners. You could do all four sides before you actually cut completely to the corners,
Make sure you cut inside of the line you have drawn and taped.
Follow up with a fine tooth file. File toward the painted surface. If you file back toward you, as you look at the painted side, you will probably chip off pieces of the powder coat.
When you remove the tape, pull it toward the cut and the chances of pulling up a chip of paint will be lessened. (If you pull it away from the cut edge, you may pull up a piece of edge paint.)
Wear goggles and hearing protection and take your time in doing this and you will get great results. The radio will most likely overlap the edge by a little bit and cover any imperfections you may create, but you should be able to make it almost perfect, if you take your time.
I have used this method successfully and it works for me.
Regardless of the method you end up using, good luck.

 

[az_gila]

Dremel cutting tool

If you cut with a Dremel disk - the way I would prefer (like sf3543) - then buy one of these 2 inch disks made by House of Balsa at your local RC model shop.

http://tinyurl.com/d54a9

The 2 inch diameter disk makes holding your Dremel parallel to the panel much easier, giving you a cleaner cut and is far easier to control. Dremel only makes 1 inch disks, so you must tilt the Dremel body to cut a flat sheet.

These wheels are essentially indestructible - they won't shatter like some of the Dremel ones....

gil in Tucson - been using these for years, it's my most useful Dremel accessory....