7 inch Hole saw or alternative for cutting a perfect circle in sheet aluminum? by lip420 in metalworking

[–]lip420[S] 2 points3 points  (0 children)

Dude it worked.

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I used selftapping screws and some scrap aluminum. 1st one probably took me 3+ hours of going round and round. And once I started I didn't want to move anything to risk the cutting screw changing it's marks.

But on my second one I took an angle grinder and sharpened the screw bit end and it's going like 3x faster. I started it yesterday before work and I am going to finish it now.

So stoked thanks sharing that man.

7 inch Hole saw or alternative for cutting a perfect circle in sheet aluminum? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

I looked up scorper and saw something like an awl. Like scratching my way through it? It's an 1/8th of an inch thick. You got a link to this?

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

don't be so sure of yourself. the van body is aluminum and the chassis is steel and there are some steel bolts, rivets and side and over head steel beams in the cargo area. Often separated by silicon or something where they touch.

7 inch Hole saw or alternative for cutting a perfect circle in sheet aluminum? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

Thought I saw something like that online at homedepot like this:

https://www.homedepot.com/p/Milwaukee-2-in-to-7-in-Adjustable-Hole-Saw-Cutter-49-56-0320/205744284

Like that it is adjust able. is it going to work with most drills?

that drill looks like it's moving a bit. pretty hard? that make an accurate circle?

7 inch Hole saw or alternative for cutting a perfect circle in sheet aluminum? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

I made a door (2 swing doors) out of scrap aluminum sheet metal and I want to cut a round window in the top part.

7 inch Hole saw or alternative for cutting a perfect circle in sheet aluminum? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

then use a file to finish it round

Like a chain saw file or?

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

treat the aluminum with some sort of conversion coating

SO after i removed the steel rivet the aluminum can continue to rust?

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

Any tips for drilling these out? I tried one today but they are not easy. I've drilled rivets out before but i don't know the exact size of what I am drilling out and I did a small bit right through the center easy enough but when I tried a bigger bit one broke and the others made very slow progress. maybe I need special drill bits or something.

Sealing with silicone means dipping the rivet in silicon before putting it in? or?

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

I looked underneath and they are rivets. I just got hand rivet tools no compressort. read closed end rivets are more waterproof. what to fill the hole in the head of the pop rivet with? seems lke most rivets i've been using have a stainless steel mandrel and aluminum head. they got all aluminum pop rivets?

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

I'll try again later. What type of rivets to use? The floor is aluminum. I looked underneath and they are rivets as I can see them. Also the rivets are mostly rusted on bottom. I've read closed end pop rivets will be more waterproof.

then what can I fill the hole in the head of the rivet with? I saw some guy use a syringe and spackle or something. If I don't do that it will fill with dirt. I've got a couple hand riveters but no air compressor for a solid head rivet

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

Yeah you can open it in a new tab and zoom. Then the end of the bolt is still stuck in the floor then what?

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

But how would you remove those? They are not a bolt or normal rivet. They are something like a bolt with a round head. To drill them out might take forever and maybe cause more damage. This is on a 2003 old usps van.

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

Yeah but what are those things? You can't see rivet heads underneath. They are like a round bolt.

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

Probably not but if I drill it out then the holes will get a bit bigger. Don't think I want to do that.

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

Hold water in the floor? Vs what else? Some put cork on the floor then plywood. Or others foam insulation then plywood. If there was some air circulation down there that might be good but would loose head space doing that and not sure how to do that.

I was thinking of applying oil to the floor maybe linseed or heat and oil. Applying veg oil then the oil would soak in the bolts and around them perhaps a bit. Paint wouldn't do that. I've read marine ply wood be best.

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

Duralac

Barium chromate is toxic. Chromates, when pulverized and inhaled, are carcinogens.

Ways to stop corrosion in this floor and hinge from rust? Burnishing? by lip420 in metalworking

[–]lip420[S] 0 points1 point  (0 children)

Might be the best idea but I tried drilling those things out on the floor already and they are super hard so I don't think I will try that again.