Cutting Aluminum Extrusion By hand

Hey guys I wondering if anyone tried cutting Extrusion by hand with a hacksaw. If one of you guys did it please tell me how straight it would be and how ruff. Thanks

Even with power tools, cuts usually aren't square when finished. A hacksaw will leave a rough surface that isn't square. If you try to build a square frame with pieces cut that way you'll have to use plates in the corners to force squareness.

I've heard that MIsumi will cut parts squarely for a small extra charge, probably well worth it because bolting the pieces directly to each other saves a lot of expense for plates and hardware.

When I build using t-slot, I cut parts a few mm longer than needed, then put them on a milling machine to square up the ends and trim them to matching lengths. When I bolt them together they come out square without any plates at the corners.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

ok thanks

I use 80/20 Inc They have many sizes already cut just select the precut sizes.

In Europe, Motedis supplies extrusion cut to size too.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

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Roberts_Clif
I use 80/20 Inc They have many sizes already cut just select the precut sizes.

If anyone uses 80/20 keep in mind they have a smaller slot size so not every drop in or slide in nut will fit. I just got some 80/20 2020 and had to order some slide in nuts that were 2 or 3 times more expensive than standard ones.

BTW if you know a cheap source for ones that work with 80/20 please let me know.

Every t-slot manufacturer has slightly different dimensions for the slot. You can buy cheap t-nuts from China that claim to fit one or another brand of t-slot, but you get what you get. A few minutes with a grinder can make nuts that are off a little fit OK. The alternative is to buy the hardware from the t-slot manufacturer and be prepared to mortgage your home to pay for them, or make your own from bar stock.

If you want to attach plates to the corners because you can't cut the ends square and bolt them directly to each other all you need is carriage bolts. 40x40 and 1.5" square t-slot has 8mm/5/16" wide slots so 8mm or 5/16" carriage bolts will fit into the slots just fine. 1" square t-slot has 1/4" wide slots, so 1/4" carriage bolts work.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Could i use a hacksaw and a mitre box to cut the extrusion

Sure. Or you could use a miter saw or a table saw with a carbide blade. But don't be disappointed when the cuts don't come out square.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I don't have access to a milling machine..but am building an all metal Delta with 330 mm printing surface and 1000mm verticals. I have a 10" radial arm saw and a drill press. I do have to print drill guides when dimensions are critical. I have evened the ends of extrusion by hand and it can be a bitch. But, I can't bring myself to spend $150 to have my heated bed plate machined when the .25" plate cost me $20. So I will cut it with a jig saw and file it to final dimension's. If you want to follow my build its posted on this forum. [forums.reprap.org] By the way, my Cartesian is made from mostly 2080 v-slot and I cut every one with my saw and squared them with a file. I spent six years in the airforce doing repairs on aluminum aircraft. Patching bullet holes in the field without machinery taught me you can get it very close with a file, square and calipers. Yes its slow, but I am retired and have the time. Have you ever ground aluminum extrusion on a table saw using the side of a metal cutting blade. Not safe but is a great way to square up a piece.

Edited 1 time(s). Last edit at 04/20/2018 03:34PM by cwaa.

I read your post completely through and I still don't know how many teeth/inch you suggest. I haven't seen so much print that said so little.

Here are some recently cut horizontal bracing for my large delta. One side is a 60 deg angle and the other side is a 30 deg cut.

My opinion is, it is only necessary that they are roughly square. (about 1 mm)

Squareness of the connection is what matters, so you connect them by an inner or outer angle. If you want, you can strengthen it by a metal sheet at the outside connecting two extrusions.

What is important: don't connect the extrusions extactly but leave a space of 1-2 mm, so the connector defines the squareness, not the (wrong) extrusion connection.

In your case, the extrusions go into some 3d part at the ends of the delta, so I would define the end by the 3d part or a stand, not the extrusion.

Edited 2 time(s). Last edit at 05/21/2018 08:06AM by JoergS5.

For cutting with a hacksaw:

mark the cutting line by holding your carpenter's angle and mark the lines with a sharp knife: on top and at the side visible to you. Saw without force and slowly at the beginning, as long as you dont't have resistance from the aluminium. You can support the saw with the nail of your thumb (but don't cut into the thumb...)

You will get experience in which direction you tend to differ from the optimal line, so you correct it by intention.

Be careful: if you saw quick, the aluminiuim gets hot.

Good luck!

Edited 3 time(s). Last edit at 05/21/2018 08:18AM by JoergS5.

Some people don't use brackets to build their frames, but simply use the center screwhole to connect the extrusions. ( crossdrilled extrusion to reach the screwhead, which slides in the T-slot)

I connected my extruders with inner angles now and it was not stable enough. I have extrusions which are exactly cut, so I connected them without space. This helped, but there is still some movement. I use 45x45 with long parts.

I remembered my experience with woodworking: if you are machining workpieces, you should fix them with two points, for example clamps. The reason is, you want to prevent spins.

I will make additional connections to my construction.

I can confirm what DigitalDentist said above - Misumi US cuts extrusion to length which is both convenient and lowers the shipping cost. I order everything this way and it's above quality.

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MatthewHall
I can confirm what DigitalDentist said above - Misumi US cuts extrusion to length which is both convenient and lowers the shipping cost. I order everything this way and it's above quality.

Are their cuts good to go as is?

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boredom.is.me
Are their cuts good to go as is?

Normally they are, at least from Misumi GMBH but all the extrusions I have looked at from them also offer a high tolerance cutting option of ±0.2mm - it is about €6 extra per extrusion here.

By hand with power tools? Or by hand tools? Either way I would hit it with a sander at the end of the cut. You wont get anywhere near mill quality without a drop saw, though. Your mates will look crappy unless hidden behind corner brackets. On that note, drop saws can come in small sizes and be cheap.