best method for interfacing linear square rail to 80/20 framing?

[louieatienza]

I've had better luck using collars on the router base as opposed to a flush trim bit with BB pilot. Only thing is the template would be undersized by the differential between the bit and rub collar diameter, divided by 2. If you use a flush trim bit I'd recommend using one with the bearing on top, this way the fan of the router blows the chips down and away instead of into the bearing and embedding into your template. But you have to be mindful that if you push the bearing into the template, it will be spinning at whatever speed the router is set up and will heat up fast, enough to ruin the template and the work. So you have to sneak up on it, so to speak.

[QuinnSjoblom]

I've had better luck using collars on the router base as opposed to a flush trim bit with BB pilot. Only thing is the template would be undersized by the differential between the bit and rub collar diameter, divided by 2. If you use a flush trim bit I'd recommend using one with the bearing on top, this way the fan of the router blows the chips down and away instead of into the bearing and embedding into your template. But you have to be mindful that if you push the bearing into the template, it will be spinning at whatever speed the router is set up and will heat up fast, enough to ruin the template and the work. So you have to sneak up on it, so to speak.

So when you used the collar in the router base with the undersized template, were you just cleaning up the edges of an aluminum part that you already cut close to the finish size? Or did you actually cut the aluminum out of a large piece? It really would be convenient to be able to just mill some of my more conplex parts out of a sheet of aluminum. What type of cutter did you use? Just a wood router bit? Or an actual end mill?

[louieatienza]

So when you used the collar in the router base with the undersized template, were you just cleaning up the edges of an aluminum part that you already cut close to the finish size? Or did you actually cut the aluminum out of a large piece? It really would be convenient to be able to just mill some of my more conplex parts out of a sheet of aluminum. What type of cutter did you use? Just a wood router bit? Or an actual end mill?

I used an aluminum cutting endmill. You can cut as much as possible with the table saw and chop saw, then use a jigsaw for the complicated parts. For aluminum, you want a TCG blade with zero or negative rake. It also helps to wax the blade, get a wax closet ring for toilet bowls, and make a couple slices on it with the blade before cutting.

[QuinnSjoblom]

I used an aluminum cutting endmill. You can cut as much as possible with the table saw and chop saw, then use a jigsaw for the complicated parts. For aluminum, you want a TCG blade with zero or negative rake. It also helps to wax the blade, get a wax closet ring for toilet bowls, and make a couple slices on it with the blade before cutting.

OK thanks. I was thinking I would buy a diabolo non ferrous 80t blade. It seems to be optimized for aluminum. I'll also make sure to keep it will lubricated. When I pick an end mill, what is going to work best for running 23k rpm? I'm assuming less flutes for higher rpm? Maybe a 2 flute and not very large diameter? I'll probably just order a bunch of cheap Chinese endmill to experiment with to see what works best

[ger21]

Get a single flute "O" flute for aluminum.
https://www.toolstoday.com/solid-car...uter-bits.html

[QuinnSjoblom]

Get a single flute "O" flute for aluminum.
https://www.toolstoday.com/solid-car...uter-bits.html

OK thanks. Here's a crazy idea if 23k rpm is just not gonna work, seems aluminum is usually milled at much lower rpm. I could buy my spindle first which will come with the clamp, and build an mdf base for it to use as a router with variable speed control. Bad idea?

[NIC 77]

OK thanks. I was thinking I would buy a diabolo non ferrous 80t blade. It seems to be optimized for aluminum. I'll also make sure to keep it will lubricated. When I pick an end mill, what is going to work best for running 23k rpm? I'm assuming less flutes for higher rpm? Maybe a 2 flute and not very large diameter? I'll probably just order a bunch of cheap Chinese endmill to experiment with to see what works best

The diabolo blade isn't necessary, any carbide tipped blade will do it, and all of the blades I've used are carbide tipped, I'm guessing most are. I just use an old carbide tipped blade and clean up the edges with my small mill when I cut aluminum.

I'm guessing it will give a better cut finish though.

Go slow, and for a chop saw, when the cut is through release the power and wait for it to stop before lifting. This prevents damage to the carbide teeth when lifting, but, really, might not be an issue. Someone told me that once and I've done it ever since.

I am aware of boat builders using routers to cut aluminum sheet, it can be done. I doubt the cut quality is great, but for an edge that will be welded after it doesn't matter so much.

Personally, I think you may find it easier to cut as close as you can using Chop saw or table saw, then use a belt / disc sander to fix the edge finish. Of course, it's easier if you buy aluminum that is the width you want so you are only cutting perpendicular to the correct width.

[louieatienza]

The diabolo blade isn't necessary, any carbide tipped blade will do it, and all of the blades I've used are carbide tipped, I'm guessing most are. I just use an old carbide tipped blade and clean up the edges with my small mill when I cut aluminum.

I'm guessing it will give a better cut finish though.

Go slow, and for a chop saw, when the cut is through release the power and wait for it to stop before lifting. This prevents damage to the carbide teeth when lifting, but, really, might not be an issue. Someone told me that once and I've done it ever since.

I am aware of boat builders using routers to cut aluminum sheet, it can be done. I doubt the cut quality is great, but for an edge that will be welded after it doesn't matter so much.

Personally, I think you may find it easier to cut as close as you can using Chop saw or table saw, then use a belt / disc sander to fix the edge finish. Of course, it's easier if you buy aluminum that is the width you want so you are only cutting perpendicular to the correct width.

Well, usually on a chop saw for wood,an ATB blade is used, and those sharp points can be on the fragile side. A TCG blade does not have the pointed teeth that ATB has, so I'd say it's a bit safer.

[NIC 77]

Well, usually on a chop saw for wood,an ATB blade is used, and those sharp points can be on the fragile side. A TCG blade does not have the pointed teeth that ATB has, so I'd say it's a bit safer.

You're right. But anything with carbide teeth will do the job. I use old blades I don't care about, I don't do it too often, but often enough, and I have knocked a couple teeth off one of them but I think that was mostly due to the piece coming loose when I was cutting it. If the aluminum is securely clamped or held in position then I haven't had any issues. Also I haven't had any issues cutting sheet on a table saw. All with carbide tooth blades intended for wood.

Not disagreeing with you at all BTW. I'm poor so I just use what I can scrounge.

EDIT: Safety glasses are always a good idea. Forgot to mention that.

[louieatienza]

You're right. But anything with carbide teeth will do the job. I use old blades I don't care about, I don't do it too often, but often enough, and I have knocked a couple teeth off one of them but I think that was mostly due to the piece coming loose when I was cutting it. If the aluminum is securely clamped or held in position then I haven't had any issues. Also I haven't had any issues cutting sheet on a table saw. All with carbide tooth blades intended for wood.

Not disagreeing with you at all BTW. I'm poor so I just use what I can scrounge.

EDIT: Safety glasses are always a good idea. Forgot to mention that.

I try to be resourceful too. But at the same time I'm careful what I suggest to others. We may be more aware of the risks.

That said many cabinet shops use TCG for things prone to chip out like 2-sided melamine or oak plywood, etc. If the OP has the means to obtain a blade for non ferrous materials, then I suggest he do so.

[NIC 77]

I try to be resourceful too. But at the same time I'm careful what I suggest to others. We may be more aware of the risks.

Have you guys ever used hand held routers to cut aluminum? It sounds a bit precarious to me. Just saying. Not saying it's safe or unsafe, but it's something I would be way more concerned about than what kind of saw blade is used in a chop saw.

I don't think what I suggested is unsafe, even if not the best blade to use. I have only lost teeth (from the blade, not mine) once, and as I said, this was because the piece came loose while it was being cut. Probably because I was trying to cut something too narrow, and as such didn't have it clamped down and wasn't able to hang onto it. So yeah, that was a mistake I made, and I recommend to others not to do that. Safety glasses are a good idea for any work with power tools. There is a greater risk of accidentally chopping a finger off than to be hit with flying teeth when cutting aluminum in my opinion. But if buying a new blade specifically for cutting aluminum, then your advice is definitely valid.

Standard legal disclaimer: I don't recommend following my example and will in no way be held liable, for negligence, bad advice, gross negligence, or by any other method of legal reasoning.

There, now I'M safe, even if the OP isn't.

[QuinnSjoblom]

Sounds like many blades will work, but most likely I'll invest in a non ferrous blade. Sounds like it will be useful even beyond building my machine, like being able to rough cut a piece of aluminum for machining with the cnc.

As for the hand router thing, I'm trying to get a good understanding of how to do it properly. From what I hear so far, it sounds like when cutting aluminum (or any metal) you want the cutter to take a substantial bite and make chips. If it tries to take too small of a bite, it will rub and burn up the bit. One guy said between 1 to 2 thousands of an inch per tooth cut on aluminum, but I'll look into that figure more. So for a 23k rpm router, that means I need to try and hand feed between 23 and 46 inches per minute with a single flute cutter, correct? The other thing I heard is that the cutter likes to bite into a surface rather than trying to wedge it's way into a shallow tapered surface which means climb feeding when machining around the outside of a shape. I can see why this would cause an issue with trying to actually cut a shape out of a larger piece of aluminum with a cut the same width as the cutter since it can't take that good initial bite with tooth. Each cut is trying to feather it's way in starting with an infinitely thin cut.

So my next question is, how do manufacturers get around this? Obviously there's plenty of cases where multiple parts need to get cut out of a large sheet of metal, so how is this done optimally? Are there specific types of cutters that are good at taking a cut the same width as the cutter? It seems in this scenario it's not possible to actually climb cut and have the tooth enter the material without feathering into a shallow cut.

[ger21]

Have you guys ever used hand held routers to cut aluminum?

I prefer to do my cutting with other tools, and just clean up the cuts with templates, and a handheld router in a router table.

Flush trim bits like this one do a really nice job, and cut very easily.
https://www.amazon.com/CMT-806-690-1.../dp/B000K29S5G

While you can cut aluminum fine with a router, I'd recommend several light passes.
Keep in mind that cutting aluminum with any woodworking tools is rather unpleasant, as you end up covered in hot aluminum chips.

There is a greater risk of accidentally chopping a finger off than to be hit with flying teeth when cutting aluminum in my opinion.

You have control over where you put your fingers, but you don't know when a saw tooth will come flying at you at 150MPH.

Sounds like many blades will work, but most likely I'll invest in a non ferrous blade.

Non ferrous blades are safer, as the negative hook prevents the blade form grabbing the aluminum, especially on a miter saw.
When I need to cut aluminum, I try to always use my table saw, with a cutoff sled. This gives me the best results.

The other thing I heard is that the cutter likes to bite into a surface rather than trying to wedge it's way into a shallow tapered surface which means climb feeding when machining around the outside of a shape

Do NOT climb cut with a handheld router, unless you really know what you are doing. And that goes double for aluminum.

[QuinnSjoblom]

I prefer to do my cutting with other tools, and just clean up the cuts with templates, and a handheld router in a router table.

Flush trim bits like this one do a really nice job, and cut very easily.
https://www.amazon.com/CMT-806-690-1.../dp/B000K29S5G

While you can cut aluminum fine with a router, I'd recommend several light passes.
Keep in mind that cutting aluminum with any woodworking tools is rather unpleasant, as you end up covered in hot aluminum chips.



You have control over where you put your fingers, but you don't know when a saw tooth will come flying at you at 150MPH.




Non ferrous blades are safer, as the negative hook prevents the blade form grabbing the aluminum, especially on a miter saw.
When I need to cut aluminum, I try to always use my table saw, with a cutoff sled. This gives me the best results.



Do NOT climb cut with a handheld router, unless you really know what you are doing. And that goes double for aluminum.

Yes, I actually have quite a lot of experience with hand routers being a cabinet worker for 15 years. Climb cutting is required a lot of the time to prevent blowing out. Yes, it's trickier when climb cutting because it tries to grab, but when done right it's not an issue. Not saying it's the same for aluminum, but with wood, climb cutting is perfectly safe if you know what your doing and required in a lot of cases.

I'll have to experiment to see what works best when using a hand router on aluminum, but I feel that I can be safe about it given my experience.

[louieatienza]

Have you guys ever used hand held routers to cut aluminum? It sounds a bit precarious to me. Just saying. Not saying it's safe or unsafe, but it's something I would be way more concerned about than what kind of saw blade is used in a chop saw.

I don't think what I suggested is unsafe, even if not the best blade to use. I have only lost teeth (from the blade, not mine) once, and as I said, this was because the piece came loose while it was being cut. Probably because I was trying to cut something too narrow, and as such didn't have it clamped down and wasn't able to hang onto it. So yeah, that was a mistake I made, and I recommend to others not to do that. Safety glasses are a good idea for any work with power tools. There is a greater risk of accidentally chopping a finger off than to be hit with flying teeth when cutting aluminum in my opinion. But if buying a new blade specifically for cutting aluminum, then your advice is definitely valid.

Standard legal disclaimer: I don't recommend following my example and will in no way be held liable, for negligence, bad advice, gross negligence, or by any other method of legal reasoning.

There, now I'M safe, even if the OP isn't.

I used to do it quite often, before my days of home CNC. The one way as Gerry mentioned is on a router table. Freehand off a template, I made a long base for my router, with a knob on one end which I placed on the other side of the cut. As Gerry says, conventional cut is the way. In actually routing aluminum can be easier because unlike wood, it has no grain, therefore no variations on density as you cut.

The table saw is the most likely place to have an accident in the shop simply because it is the most used tool. The risk of appendage loss is always there,it doesn't need to be compounded with loose carbide, or kickbacks. Add to it the likelihood that you wouldn't have the anti-kickback pawls on the saw either, especially with aluminum. Blades for wood by the way have large gullies between teeth for chip evacuation which leads to a more aggressive cut - too aggressive for hand operations. The gullies on metal cutting blades are smaller, they take a smaller chip. And the teeth are stubbier, and more robust, with a thicker rim for more brazing surface and obvious stiffer rim. I could go on further with explanations ad nauseum. Whether you think it's safe or not doesn't necessarily make it so. The danger is suggesting that it is.

Look you could potentially die from a papercut. And all tools seem safe until the day mishap occurs. I almost lost my thumb on the tablesaw on a freak accident, and my thumb never touched the blade.

[QuinnSjoblom]

Well, after watching a video of a guy zipping through a 10mm plate of aluminum with a jigsaw in a few seconds, I'm not worried about it. I'll do what I can on the table saw and chop saw with the non ferrous blade and do the rest with a jig saw, leaving parts oversized and cleaning up with a flush bit like gerry posted. Shouldn't be a problem. Even if the plate could actually be cut with an end mill in the router, there's just no way it would be as fast. I had the impression that cutting with a jigsaw would be a super slow process and foul blades quickly but that doesn't seem to be the case. Thickest parts are 12.7mm, no problem for jigsaw on the more complex parts.

Thanks for all the advice guys. You don't need to worry about me when it comes to safety. I've been working with power tools for a long time and understand the dangers. I also understand that some of the suggestions made are ways that you've tried, but not guaranteed to be safe. I will be very cautious with safety in mind

[QuinnSjoblom]

All building materials and tools arrive tuesday. Found a non ferrous blade for 20 bucks. We'll see how that does. Really underestimated the price of building with extrude. The extrude itself was only 350 with the black Friday sale but then I needed 250 bucks worth of t nuts and bolts. That was even buying off brand nuts from ebay. 80/20 wants a buck a piece and I need 300 of them lol. Also spent about 250 for all my half inch and quarter inch plate for gussets and other parts. Pretty excited to get building

[1Jumper10]

Yes, the cost of building with extrusion doesn't seem too bad. But I never looked at the cost of the hardware because I figured it was relatively insignificant. But you're right. It's not. It is easier than building with steel though. Good luck with your machine.

[QuinnSjoblom]

yep, about 800 total to build a decent frame and thats making your own gussets from aluminum plate. Would have easily been a couple hundred more if i bought premade gussets from 80/20. im also making my own corner brackets out of 3 inch, 1/4" wall 90 degree aluminum angle. ill slice it into the widths i need and drill bolt holes. I probably could have built a machine without extrude and just used aluminum tubing and plate, just would have been more work. Aluminum square tube is obviously a more efficient structure vs t slot when it comes to strength vs weight, just a lot more effort connecting everything together. More drilling, tapping, cutting, etc. Like i mentioned before, this wont be the last machine i build. Now that ill have a cnc, ill have the ability to make nice accurate gussets with precisely drilled holes, specialized parts, etc.

After talking with the ebay seller that sold me the linear motion stuff, they agreed to send replacements for the carriages that had a bit of slop in them. Out of the 12 originals, 6 were perfect, 3 were ok, 3 had significant slop. They agreed to send me 9 of them so i can pick out the best ones and send back the rest. Definitely shows that you get what you pay for, but after a bit of effort, swapping out some of the carriages, ill have a really nice setup for WAY less money than brand name stuff.

[ger21]

im also making my own corner brackets out of 3 inch, 1/4" wall 90 degree aluminum angle

Aluminum angle is often not very square, so you should check it.