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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Tikvah on July 05, 2011, 03:56:51 PM

Title: Cutting Aluminum skin
Post by: Tikvah on July 05, 2011, 03:56:51 PM
I have the bus skinned, now I need to cut out the window openings.
I've tried my sawsall.  With a fine metal blade it is painfully slow.  With a more aggressive all-metal blade it's beating me to death and tearing up the blades.

I've thought of the grinder (that's how I started the hole), but I'm afraid of making too much heat..... I don't know, maybe the side-grinder with a thin blade.

I'm open to ideas.

The Aluminum is .080  6061-T6

Too thick for my air nibbler and too thick for my air sheers.

Dave
Title: Re: Cutting Aluminum skin
Post by: bevans6 on July 05, 2011, 03:59:34 PM
I use plain old wood blades for aluminium.  Yes, they do beat you up a bit.  High speed, low feed.  Don't push on the tool.  wear ear protection, it will be loud...  Grinders are not recommended for cutting aluminium, you can seriously load the disc up and it can explode.  i have scars to prove this old wives tale - five stitches!

Brian
Title: Re: Cutting Aluminum skin
Post by: junkman42 on July 05, 2011, 04:15:51 PM
Use a die grinder or any high speed grinder with cloth resin reinforced wheels.  They will not load up but if they do just run them against a piece of brick or concrete block to clean the accumulated aluminum off.  move slow and it will cut fine!  Heat should not be a problem on aluminum but could be a problem on stainless You intend to polish!  John L
Title: Re: Cutting Aluminum skin
Post by: Tikvah on July 05, 2011, 04:49:34 PM
Well, I got one window cut open.... Maybe I'm getting old  ;)  I feel like I got kicked by a horse.

It didn't do too bad grinding the rough edges off, but I'll need to buy some thin wheels to try cutting with the grinder. 


I'll let the group know what I decide to do.
Title: Re: Cutting Aluminum skin
Post by: buddydawg on July 05, 2011, 05:01:13 PM
I've done most of my cutting with a jig saw and a wood blade.  I usually start the cut with a thin grinding wheel, once it cuts thru I finish with the jig saw.  It cuts nice and easy. Debur and finished.
Title: Re: Cutting Aluminum skin
Post by: Chopper Scott on July 05, 2011, 05:16:34 PM
Try some thin cutoff wheels on your small hand grinder (4 1/2"). They generally wear out pretty fast so they won't have a problem with loading up. Practice on a piece of scrap with any option you choose. I didn't need to tell you that but you know how it is around here sometimes.
Title: Re: Cutting Aluminum skin
Post by: boogiethecat on July 05, 2011, 05:50:15 PM
I'd use a plasma cutter. It'll cut like a hot knife thru butter and go so fast that the aluminum won't even get hot... that's how I did my trailer and it was amazing...
Title: Re: Cutting Aluminum skin
Post by: Nusa on July 05, 2011, 06:08:28 PM
In general wood-working equipment works on aluminum. Ideally slow the equipment down if you have variable speed ability (jigsaws, routers) or by using smaller diameter blades on circular saws. Feed it slower than wood. Lubricants will help if you don't mind the mess. Any kickbacks will be more violent than with wood, so pay attention to safety, and keep people well clear of the kickback zone.
Title: Re: Cutting Aluminum skin
Post by: Hal on July 05, 2011, 06:30:23 PM
I used .080 also and used a router with lots of WD40 to lube the cutter. Keep it slow with a good grip on things. Its a two person job for sure, one spraying, the other cutting. Be safe, Hal
Title: Re: Cutting Aluminum skin
Post by: Fred Mc on July 05, 2011, 07:42:48 PM
I would line the al. with masking tape (to avoid scratching the surface) and then use a skill saw to cut the straight lines.. You can get a blade for al. but you could also use a regular carbide tipped blade.  Then cut the corners with a jig saw. I cut al. a lot with a table saw and a miter saw and use regular wood cutting blades.
No need for messy lubricant. Wear good ear protection.

Fred
Title: Re: Cutting Aluminum skin
Post by: skihor on July 05, 2011, 07:58:14 PM
They make a blade for a skil saw that is just for cutting aluminum. I bought one from a metals dealer when I did the diamond plate in my trailer. Many yards of cutting and still sharp. EAR PROTECTION required.

Don & Sheila
Title: Re: Cutting Aluminum skin
Post by: demodriver on July 05, 2011, 08:26:31 PM
IF I remember right we turned a wood blade around on our circular saw to cut alluminum when I used to do construction.
Title: Re: Cutting Aluminum skin
Post by: Ed Hackenbruch on July 05, 2011, 08:37:20 PM
How about a Dual Saw as seen on tv? ;D
Title: Re: Cutting Aluminum skin
Post by: Iceni John on July 05, 2011, 08:55:39 PM
For cutting aluminum I use the cheapo throw-away Russian-made cutting wheels from Harbor Fright  -  at less than 50 cents each it doesn't matter that they only last for a few feet or so.   Expensive USA-made wheels don't last any longer cutting aluminum, but I do use them for cutting ferrous metals instead of HF's wheels.   So far I've cut out three openings for extra access doors, with a fourth to be done soon, and it's easy to make straight cuts with an angle grinder.

John
Title: Re: Cutting Aluminum skin
Post by: Len Silva on July 06, 2011, 04:23:06 AM
I've never tried it on aluminum it I'm a fan of the Roto-Zip spiral saws and they claim to have metal blades available.  If it worked, it would give you a nice smooth cut right up against the window frame.
Title: Re: Cutting Aluminum skin
Post by: muddog16 on July 06, 2011, 05:02:10 AM
I used a dewalt 4 1/2" grinder with cutting wheels.....9 windows 4 wheels...took about an hour.  I spent more time laying them out than cutting them.....on that plasma cutter......lol........call the local fire department or have a fire watch on the other side!
Title: Re: Cutting Aluminum skin
Post by: belfert on July 06, 2011, 07:45:38 AM
I have used a saber/jig saw to cut aluminum.  I'm thinking an air powered body saw would work good.

(I accidentally called a saber saw a scroll saw when I first posted.)
Title: Re: Cutting Aluminum skin
Post by: bottomacher on July 06, 2011, 08:07:19 AM
I always use a carbide, fine tooth circular saw to cut everything from thin sheet to about 1/4" plate. Keep the saw steady and take your time. Curves require a jigsaw or sawzall (more difficult to keep steady.
Title: Re: Cutting Aluminum skin
Post by: Charles in SC on July 06, 2011, 06:36:15 PM
One of the challenges when using a saw such as a jigsaw is to keep from scratching up the surface with the foot. When using a saw it works best to use a cutting lube oil to help keep the saw teeth from loading up. A router works great. A die grinder works great but you need to find out what wheels work best.
Title: Re: Cutting Aluminum skin
Post by: robertglines1 on July 06, 2011, 07:39:06 PM
Still just use the old air chisel with the prong sheet metal cutting bit. cut radius and all. no heat ,no grinding and no warping.
Title: Re: Cutting Aluminum skin
Post by: luvrbus on July 06, 2011, 08:45:23 PM
I use a trim router with the carbide bit for aluminum cost about 25 bucks at Lowes for the bit



good luck
Title: Re: Cutting Aluminum skin
Post by: robertglines1 on July 06, 2011, 08:51:04 PM
Haven't tried the router yet sounds good. I like the air chisel even on the stainless steel -seams the stainless eats everything else and the chisel doesn't care. Will try the router on the Alum. Good idea.
Title: Re: Cutting Aluminum skin
Post by: Charles in SC on July 07, 2011, 05:45:07 PM
Quote from: robertglines1 on July 06, 2011, 08:51:04 PM
Haven't tried the router yet sounds good. I like the air chisel even on the stainless steel -seams the stainless eats everything else and the chisel doesn't care. Will try the router on the Alum. Good idea.

When you try the router, do not try to hand guide it. Set up a guide and wear eye protection. The debris from it is like aluminum snow.
Title: Re: Cutting Aluminum skin
Post by: Hal on July 07, 2011, 09:17:22 PM
You'll need to use a panel cutting router bit, it will have a ball bearing guide. Works great. Like I said earlier, I used .080 aluminum too and it worked great. Hal
Title: Re: Cutting Aluminum skin
Post by: bergdoll on July 08, 2011, 03:31:36 AM
Jigsaw. There are a variety of blades, a fairly decent, name brand one is around $50., & it's pretty easy for making the corner radius cuts.
Title: Re: Cutting Aluminum skin
Post by: Tikvah on July 08, 2011, 06:02:25 AM
Well, I ended up using my side grinder with a very thin cutting wheel.  I used the jig saw on the corners to cut the curve.  The jig saw was fine, but went through about two blades per window.  With the grinder I can do almost one window before changing wheels.  But, in the end, the side grinder gave a nice smooth cut.  It did heat the aluminum and stretch it, but when it cooled it went right back.

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi887.photobucket.com%2Falbums%2Fac78%2Fcozyheatdave%2FCoach%2F2011-07-08_08-29-52_244.jpg%3Ft%3D1310129950&hash=cfa7f378430c2aa8b2b524f04710a37bfda1f172)
Title: Re: Cutting Aluminum skin
Post by: robertglines1 on July 08, 2011, 06:05:29 AM
looks  great      next!
Title: Re: Cutting Aluminum skin
Post by: buddydawg on July 08, 2011, 06:48:35 AM
I don't know what blade you used in the jig saw to cut the aluminum.  You can try the DeWalt DW3705 it has 8 TPI and is made for Aluminum/Fiberglass.  If you use a blade made for cutting steel it will load up quickly and be useless.  In general you can use the same blades for aluminum that are made for wood.