hole about 10mm dia along 20mm thk ali plate 200mm through?

I have a decent Tennsmith, Harbor Freight basic 30in, a vise brake, and a hydraulic press brake. It can definitely be tricky. Also, the thicker it is the larger radius you should try to bend. You can fake this with a box brake, by setting the clamp fence back from the bending surface and sandwiching layers of pressed cardboard between the sheet and the clamp.

If you try to bend to sharp with no radius the aluminum tears.

The cleanest tightest bends I have made were by making partial thickness cuts, bending by hand across a tractor bucket or a trailer fence rail, and then making a fillet weld on the inside. The outside looks cleaner than an outside corner weld, and its easier. Bob La Londe

------------------------------------ I was taught that to fold sharp corners in aluminum outer window frame covering. Otherwise I respect the numbers in sheet metal bend radius tables. Corners on machines shouldn't be too sharp anyway.

You can bend with a radius on the 30" press brake by reversing the dies, flat end down, and using them to press a rod into the female die. The rod could be taped in place but I didn't need to. The bend allowance is negative, like conduit.

I bent vees in narrow scrap strips that pad the lower die to adjust for a right angle in different thicknesses of stock. It's easier than fiddling with the adjustments and doesn't scratch the outside as much.

The primitive squaring guide on mine now clamps a ruler to square and measure.

The rollers made stainless steel stovepipe from scrap. That alone half paid for the machine.

The order of these arrived today, to replace the brittle plastic clips that retain the trim on my car with stainless.

With flowing water you really don't need a huge internal volume for your cooling plate/s. DIY cooling plates are often functionally just a U shape passage inside the plate. They drill two deep holes from one edge, and drill a cross hole from a perpendicular edge, then plug the end of the hole. I find deep drilling tedious, and of course there is some risk of wander and blowout, but lots of DIYers with a lot less knowledge and skill than you or I successfully do it with woefully inadequate tools.

The cooling plate gets finished with all three entry holes threaded. One gets a pipe plug, and the other two get hose fittings.

Aluminum transfers heat really well. Just that small amount of water flowing continuously works pretty well. For fast cooling they will often drop a pond pump in a bucket of ice water. Mostly ice to start.

I think my point in some of my previous replies is maybe you don't need to overthink it.

Ideally you need a water passage with ways to safely get water in and out, but wet rags might do the trick instead if you aren't afraid of electrocution.

Most of the ideas presented from complex to stupid simple "can" work, but its up to you to decide/determine what falls within your resources, capability, and acceptable risk.

A job I do from time to time involves drilling a hole through 150mm of

You can bend with a radius on the 30" press brake by reversing the dies, flat end down, and using them to press a rod into the female die. The rod could be taped in place but I didn't need to. The bend allowance is negative, like conduit.

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I made another radius bend yesterday to match a car part and remembered more. The square bottom of the dies can indent the sheet metal enough to form a valley that will hold the sheet and rod in place on the lower die.

I assume that is for something like a press brake.

I assume that is for something like a press brake. Bob La Londe

--------------------------------- Yes, the 30" 3-in-1. Is that your HF 30"?

At Mitre my model shop had conventional Pexto shear and Roper-Whitney finger brake machines plus a Taiwanese 24" 3-in-1 of better than Chicom construction. Only the 3-in-1 on wheels would have been both small and capable enough for my home shop though I greatly preferred the convenience of the old American iron.

My 8" lever shear has seen quite a bit of use recently on metal too large or thick for the 3-in-1. It handles 1/8" if clamped down, 18 gauge if held down by hand. Usually I put it on the driveway retaining wall where it's handy to trim car repair parts.

No, my HF 30 is a pan brake. Its got a single bar (no fingers), but it is still a hinged platten style folder. I never use it. I have a 48" Tennsmith box and pan brake and a 12" hydraulic press brake that get all the use. Even my vise brake has been used more recently than the HF 30. I used to use it for bending stainless wires until I made and bought a couple wire and small rod benders.

Problem would be the steam coming off it. Ali + water / moisture don't go together well (lots of blowholes / porosity) In the outboard-motor for boat case the wet rag is near the gear-shafts and sitant from the weld.

In my case the wet rag would be very close to the weld and the steam coming off risks messing-up the weld.

Can see where this is a good idea - but cannot see it working well in this case.

Regards, Rich S

Sounds good. Thought of milling wide-ish small-depth channels surrounded by a groove for an O-ring gasket. Water flowing against the weld-test-plate surface. But still sealed away from the weld environment.

Thanks again so much everyone.

Facing the difficulties, I sidestepped the whole issue. Started with bead-on-plate welds on several pieces of ali rotated around weld-and-cool. Being bead-on-plate and looking only at the run of the weld-bead can simply dip in water...

Sealed-system water-cooling would come back far in the future when getting apparently excellent welds showing good properties - and it is time to prove it. By then you'd probably be instrumenting with thermocouple(s), etc.

So again - thanks very much all of you, Regards, Rich Smith

On Thu, 16 Jul 2026 15:38:39 +0100, Richard Smith wrote: ...

Holes that deep (about 21 diameters, 200/9.5) can be drilled with gun drills. But "5083 aluminum is moderately sticky and prone to gumming up during drilling" (per google) so peck drilling and clearing chips might be pretty tedious. Maybe drill halfway from each side with a slightly-under bit, then clean up with a 3/8" bit.

Consider buying some 40mm x 200mm x 12mm water cooling blocks (US cost about $26 per pair) and using one as the work surface, or fastening several to your 5083 plate. How hot will the heatsink get? That might affect whether you could use heatsink compound.

On Thu, 16 Jul 2026 15:38:39 +0100, Richard Smith wrote: ...

Holes that deep (about 21 diameters, 200/9.5) can be drilled with gun drills. But "5083 aluminum is moderately sticky and prone to gumming up during drilling" (per google) so peck drilling and clearing chips might be pretty tedious. Maybe drill halfway from each side with a slightly-under bit, then clean up with a 3/8" bit.

Consider buying some 40mm x 200mm x 12mm water cooling blocks (US cost about $26 per pair) and using one as the work surface, or fastening several to your 5083 plate. How hot will the heatsink get? That might affect whether you could use heatsink compound.

-------------------------------------- Maybe this is a result of being sleepy. I wonder if a drill bit would tend to follow the joint between two 10mm plates bolted together. If not the line could be piloted with saw cuts. The hole would be the OD of aluminium tubing, and aluminimum foil on the cool side could shim it tight.

to follow the joint between two 10mm plates bolted together. If not the line could be piloted with saw cuts. The hole would be the OD of aluminium tubing, and aluminimum foil on the cool side could shim it tight.

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If that works a simple way to move the water is a water bed drill pump with garden hose fittings. Rubber and vinyl tubing easily adapt to straight metal tubes with hose clamps, pipe thread with barbed adapters and garden hose thread with repair fittings. A sump pump in the lower reservoir and bulkhead fitting with shut-off valve to the cooler in the upper one would automate the coolant flow and limit overpressure if a hose kinks. I've seen those fittings to modify a trash can into a rain barrel. Mine were turned and threaded on the lathe from repair ends.

I find explaining and demonstrating something distracting enough that I forget steps like turning on the water.

A hand-held drill makes pulling out the bit to clear chips and add cutting fluid simple. If you don't have a twist bit long enough a gun-type deep hole drill bit can be hand ground from hardenable steel rod, Silver Steel. Several edge shapes work, I like D bits. They dull quickly if not hardened, have little chip space and need to be pulled out often, and they don't cut as aggressively as twist drills. Besides ease of making and resharpening they are stiffer than twist drills. Aircraft and bell hanger drills have short fluted twist sections and long full shanks and may cut faster if you can find them.

Larger drill bits cut much faster with a pilot hole the size of the blunt center web.