1.In order to cut aluminum with a dremel, what cutting blade do I need?
you can use the 1.5" reinforced cutting disks for Metal. The original screw on type, or the EZLock system (which I recommend) work wonderfully
2.Is there anything I should know before cutting the metal?
(answering based on using a Dremel) yes, steel and aluminum behave differently when being cut. Alu is softer than steel and will try to bind the blade more often than steel (if all other factors are constant). You will experience more run-overs and partial binds when cutting alu as opposed to steel. Hold the tool firmly at all times, do not cut blind (where you cant see the cut happening due to view angle or obstruction, and always cut from your right towards your left. The dremel spins clockwise so you want to cut in the opposite direction of the way the wheel is attempting to "roll". Right to Left not only is more efficient, but its safer (less binds/run-overs) Press lightly and make many even passes to cut lines, avoid power-plunging.
3.What kind of Acrylic do I need to buy for a window?
Normally cast acrylic is used, both for its durability and the options it allows when cutting.
4.What is special about cutting Acrylic?
its an acquired art-form as most will tell you. there is no set formula for it, it really depends on what tool you are using but the goal is always to avoid melting and cracking. First best way to avoid these damages is to put blue painters tape on both sides before cutting, even if it is paper backed. I did a test the was causing some minor melting, I added tape to both sides and changed nothing else (tool had variable speed spm setting unchanged) and the taped cut had no melting. The tape helps cool the blade. Yeah I didnt believe it at first either. Trust me its true. In my experience so far with it, for drilling holes, go slow (lowish rpms) and let the weight of the drill and gravity do the pressing, you only need add a hair's-pressure. For straight cuts and for freehand cuts I invested in a good scroll saw. I cant tell you how absolutely wonderful that tool is for cutting acrylic (among other materials like wood and metal). Its worth looking into.
5.How do I polish cut acrylic?
theres better people to answer this, so I will defer to their experience
6.What is 'Wet Sanding?'
exactly what it implies, sanding a surface with special sand paper (3M Imperial WetOrDry comes to mind) using (usually) water with a drop or two of dish soap. The water and soap keep the sand paper from clogging. Always wet sand in one direction and wipe the surface with a damp cloth every few sand strokes to remove grit and keep the paper healthy longer. (tips hat toward Bill Owen)
7.How do I get rid of spray paint drips?
this is an easy one, avoid creating them in the first place. If drips are forming then the technique being used isnt right. Usually from either being to close or not moving the spray stream across the material fast enough. I'd suggest watching some videos on mnpctech and watch Bill paint. If that doesnt inspire then I dont know what will
8.Should I sand the metal before painting?
yes absolutely, and clean it. Sanding with a semi-coarse grit like 240 or even 320/400 will give the surface just enough "roughness" for the primer to grab onto, but wont show any scratches thru, even when using a thin primer like self etching primer, on metal. For other materials the grit needs match the application. ie how you would prep acrylic vs how youd prep untreated steel, etc. After sanding I clean metal with a blower, then use Rubbing Alcohol 91% or you can use Denatured Alc, or acetone. Let evaporation happen for 15 mins before any priming begins
9.What sort of file should I use to smooth my cuts?
I find that double-cut bastard files work great. I have a few shapes and sizes but your best bet is to have a half-round on hand. It will have a flat side and half round side, so you can debur not only straight cuts, but fan hole cut outs and cuts with arcs etc. Also a small chainsaw file is good for drill holes that are too small for the half round.
Any extra help?
SAFETY GOGGLES ALWAYS. and get a pair of rubber ear plugs for those long metal work cutting sessions, you ears and eyes will thank you by performing flawlessly for years to come.
10. Has anyone used Black & Decker rotary tool, instead of a Dremel? Can Dremel attachments (particularly circular/straight line guide) be used on it? (B&D tool costs half as much)
cant say that I have but I think I recall that the dremel mandrels and bits can be used in the BD. Dont quote me tho, check into it
11. Syrillian mentioned carbide sideways (spiral) bit. Could you let me know which specific one you use? I tried the multi-purpose bit, recommended by a rep at home depot and it was making very uneven cuts and broke when I used it on aluminum case panel
the one the dremel comes with is not bad but I wouldnt ever cut metal with it, at least not to any degree other than a small notch or something, if I needed to. I will defer to others here on this one tho. Might work ok in acrylic at the right rpm.
sorry to ramble - hope that helps you
off to the shop now, cyaEdited by CattleRustler - 8/18/08 at 4:41pm