I purchased an 8 foot length of kitchen countertop for my basement workbench.
Braced and supported at either end by some old sturdy wood cabinets and some 2x4's
It'll outlast me.
My "Bench" is a 15$ table from Ikea. At least it was 15$ when I got it...
LINNMON / ADILS Table, white, 393/8x235/8" (100x60 cm) - IKEA
LINNMON / ADILS Table, white, 393/8x235/8" (100x60 cm) - IKEA
The quick "fix the workbench" moment has snowballed into a rebuild the whole basement lab kinda thing.
As of now the original bench is fixed, but I'm still moving stuff around to get things where I want them. It will be used mostly for tube stuff and other large or heavy things.
The old "leaning tower" equipment rack got some bracing....so I could stuff more equipment in it. It is now bolted to both benches as well.
The corner bench got it's shelf raised several inches and some extra bracing added for better load management. The short side, the rack, and the corner is for RF work. The long side and the Ikea table next to it (not visible) is the synthesizer lab where analog, digital, and mixed mode sound generation experiments get turned into synthesizers or modules.
The bench tops and shelves are both covered in random samples of hardwood flooring, hence the different colors. It has gotten scratched, but it takes a beating. Hey, it was all free.
There are also two large benches from a school lab. I got them for $20 each. One is currently unused but will probably host a 3D printer. The other is where stuff gets assembled and soldered.
There are also two more Ikea tables, all oddballs from their clearance section. The long skinny one hosts an old Roland JV1000 music workstation from the 1990's that's been waiting for me to rebuild it for several years. The roll around table is still unassembled. I'm not sure what I'll do with it.
As of now the original bench is fixed, but I'm still moving stuff around to get things where I want them. It will be used mostly for tube stuff and other large or heavy things.
The old "leaning tower" equipment rack got some bracing....so I could stuff more equipment in it. It is now bolted to both benches as well.
The corner bench got it's shelf raised several inches and some extra bracing added for better load management. The short side, the rack, and the corner is for RF work. The long side and the Ikea table next to it (not visible) is the synthesizer lab where analog, digital, and mixed mode sound generation experiments get turned into synthesizers or modules.
The bench tops and shelves are both covered in random samples of hardwood flooring, hence the different colors. It has gotten scratched, but it takes a beating. Hey, it was all free.
There are also two large benches from a school lab. I got them for $20 each. One is currently unused but will probably host a 3D printer. The other is where stuff gets assembled and soldered.
There are also two more Ikea tables, all oddballs from their clearance section. The long skinny one hosts an old Roland JV1000 music workstation from the 1990's that's been waiting for me to rebuild it for several years. The roll around table is still unassembled. I'm not sure what I'll do with it.
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LOL... what you and I found out the hard way is a little number known as Area Moment of Inertia. It's a measure of stiffness used extensively in engineering, and is expressed in units ^4. Yes, I know it's weird but it all works out in subsequent calculations.
For a rectangle the formula is I = (b x h^3)/12, so for a common 2 x 4 placing the stud on edge yields an I of 5.35 in^4 (223 cm^4) if you ignore the corner roundovers and use the finished dimensions of 1.5" x 3.5" (3.8 x 8.9 cm). Placing the material flat yields an I of 0.98 in^4 (40.7 cm^4), a decrease in stiffness of over five fold. Oof!
Punching shear was the failure mechanism behind the 1995 Sampoong department store collapse. I don't think I've ever heard of a workbench failing in that manner, but I'm glad nobody was injured. It's a shame about the equipment damage though. And lest you get the idea I'm on some sort of high horse here, I can assure you I've likewise found ways to royally screw up.
Looks like the rest of your area is coming along quite nicely.I incorporated one of those on my own workbench immediately after reading the electrical safety section of your website. Thank you!
And for the sake of staying on topic, a small repair today. Swapped out a defunct DVD player in my media PC. Not a big deal perhaps, but hey... it is what it is.
Oh dear, I'm lucky it wasn't that! It was a strange wire, but easy enough to solder when I figured out what it was.
I thought about using a laminated kitchen countertop for my bench. It's basically bulletproof, but it's tricky to find anything much deeper than 30" at surplus. I knew I wanted my bench to be closer to 40" deep.
I got a couple of the laminated counter tops that are sold at Lowes from a relative that had them in his basement. I don't think that they are even 30 inches deep. I came to the conclusion that they were not deep enough for use where space is not an issue. They are now in the garage.
My big bench is 42 inches deep and the small one is 34.
My big bench is 42 inches deep and the small one is 34.
If you're going to pull everything back, then I recommend you put a sealer on those porous blocks. I recommend this. Drylok White Latex Waterproof Sealer 1 gal - Ace Hardware It's a basic white finish, rather industrial in appearance. I have painted over some of it with conventional latex interior paint with no problems and it looked really nice.
I had a "leaning tower" of my own and it collapsed. One brace had snapped and the whole thing came down. It was cheap plastic and ridiculously overloaded.
Some of my shelving is the Lowes plastic utility "pop together" ones.
I have them secured to the wall behind them for stability.
Decent for the money, though really heavy objects can cause shelf-sag over time.
That can be eliminated easily by reinforcing beams fastened underneath.
I don't deal with large or heavy things in my basement shop, except for those few monster amps and tape decks, speakers, from my neighbor.
But I cut that out since then, I'm getting to old to wrestle that, and basically stick to smaller stuff.
The kitchen countertops are standard depth 25" w/backsplash laminate, just fine for what I need them for, and the 8 foot length is plenty wide.
A 10" 3/4 thick pine board flush behind the backsplash gives me room for parts bins and some test equipment.
Other larger equipment is under-counter or on a seperate wall shelf above.
I have them secured to the wall behind them for stability.
Decent for the money, though really heavy objects can cause shelf-sag over time.
That can be eliminated easily by reinforcing beams fastened underneath.
I don't deal with large or heavy things in my basement shop, except for those few monster amps and tape decks, speakers, from my neighbor.
But I cut that out since then, I'm getting to old to wrestle that, and basically stick to smaller stuff.
The kitchen countertops are standard depth 25" w/backsplash laminate, just fine for what I need them for, and the 8 foot length is plenty wide.
A 10" 3/4 thick pine board flush behind the backsplash gives me room for parts bins and some test equipment.
Other larger equipment is under-counter or on a seperate wall shelf above.
I used some of that latex sealer paint on porous clay flower pots. I had tried painting them before without success. I had some sealer paint left over and so I gave it a try. I topcoated it with exterior latex paint left over from other projects (handy since the pots match the railings perfectly).
I did this 4-5 years ago and they still look great. A couple pots go inside in the winter and outside in the summer. One pot goes in the shed over the winter. The paint has held up great.
I did this 4-5 years ago and they still look great. A couple pots go inside in the winter and outside in the summer. One pot goes in the shed over the winter. The paint has held up great.
The benches are already back in position.
When we had the house built I discussed this with the builder who explained that they seal the block from the outside with two different coatings. The first is similar to Dry-Lock and the second is a thick black tar like substance. They recommended NOT to seal the inside.
Apparently sealing the block from the inside only can be real bad in wet locations like here. If water gets trapped inside a block and then freezes the block can shatter possibly causing a catastrophic event. It seems that it happened a few times over the years.
I have been a dumpster diver since high school. One of the stops on my "trash tour" was the depot for the local cable company. They were upgrading the system and tossing all sorts of rack mounted equipment. I just wanted the cases to build stuff in. I even got one of the guys to save me some boxes with minimal holes for reuse. I went there before work one day and the guy asked me if I wanted any racks. Most of them were ugly and rusty, but I got a couple good ones. This rack was made of the best parts of several racks.
I also had some really big and heavy 4 post racks from the Systems Engineering computer plant down the street from Motorola. They were too big to move 1200 miles, so they went to the metal scrapper when I left Florida.
I have some really nice rack mounted server cases, but I haven't used any of them yet.
I put a couple projects in very stout "Muzak" brand amplifier cases. These are amplifiers that drive multiple speakers for a building or gym. Paso Muzak Digital Music Amp DMA2060 60W 4 Channel Amplifier | eBay Of course I painted them and used nice aluminum knobs. They look very "high end" and understated. The cases are very stout compared to consumer equipment, and they weigh a ton.
It makes sense about the sealer paint. My house was not built with external sealer but a couple cracks had black tar like stuff applied at some time before I bought it.
I had a "magic waterfall" a couple times where water poured right out of a couple of blocks. There were no visible cracks; the water was leaching right through the blocks. I regraded that side of the house (tons and tons of dirt) and sealed the whole interior wall with sealer paint. It's worked so far.
There are some freeze/thaw damaged bricks on the garage.
I put a couple projects in very stout "Muzak" brand amplifier cases. These are amplifiers that drive multiple speakers for a building or gym. Paso Muzak Digital Music Amp DMA2060 60W 4 Channel Amplifier | eBay Of course I painted them and used nice aluminum knobs. They look very "high end" and understated. The cases are very stout compared to consumer equipment, and they weigh a ton.
It makes sense about the sealer paint. My house was not built with external sealer but a couple cracks had black tar like stuff applied at some time before I bought it.
I had a "magic waterfall" a couple times where water poured right out of a couple of blocks. There were no visible cracks; the water was leaching right through the blocks. I regraded that side of the house (tons and tons of dirt) and sealed the whole interior wall with sealer paint. It's worked so far.
There are some freeze/thaw damaged bricks on the garage.
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Hey anyone, I have a Kennergetics KBA-280 on the bench and have turned over all kinds of rocks looking for information on it. It was made in California. It is extremely difficult to work on and I have to find a schematic for it.
One issue is the turn on surge, much higher than can be explained by supply capacitance. It is a "Class A" design, and this one appeared in a state where I was unable to spark it up. It still blows fuses sometimes even though it has a soft start circuit from a report I have from the owner.
I'm on the fence as to whether it should be repaired or not. This person owns two of this model and the second has started doing the same thing. My feeling is that it has a fatal design flaw.
One issue is that the idiots soldered the jam nuts together on the output binding posts at the factory, so I have to break them to go any further. I do not want to subject the owner to any further costs if it can be avoided. He really wants to repair them, but if they aren't going to be reliable I have to advise him against that.
-Chris
One issue is the turn on surge, much higher than can be explained by supply capacitance. It is a "Class A" design, and this one appeared in a state where I was unable to spark it up. It still blows fuses sometimes even though it has a soft start circuit from a report I have from the owner.
I'm on the fence as to whether it should be repaired or not. This person owns two of this model and the second has started doing the same thing. My feeling is that it has a fatal design flaw.
One issue is that the idiots soldered the jam nuts together on the output binding posts at the factory, so I have to break them to go any further. I do not want to subject the owner to any further costs if it can be avoided. He really wants to repair them, but if they aren't going to be reliable I have to advise him against that.
-Chris
USB dual channel oscilloscope design.
It had steps in sine waves when viewed on PC screen.
I use a PIC micro to a2d signals via USB to a PC.
According to data sheet it should do 500KHZ max sampling rate.
I managed to get 3.3MHz sampling but got steps in the waveform.
Using interrupts to get the data slowed it down. There seems to be a bug in the PIC where it gives out 2 interrupts for one scan of the 2 inputs. This seriously slows it down.
So I used the go/done flag instead and this improved things by a factor of 2.5.
I found in the end the sampling rate was too slow and this caused the steps.
I turned down sampling steps to 1 and the steps disappeared.
So getting much more sampling rate out of PIC than they say I can or recommend.
Probably good for 100KHZ wave at best so good enough for audio or sub 100KHz square waves.
I have 2 other designs which go much faster (17M/S and 22M/S) but they use external a2d's.
It had steps in sine waves when viewed on PC screen.
I use a PIC micro to a2d signals via USB to a PC.
According to data sheet it should do 500KHZ max sampling rate.
I managed to get 3.3MHz sampling but got steps in the waveform.
Using interrupts to get the data slowed it down. There seems to be a bug in the PIC where it gives out 2 interrupts for one scan of the 2 inputs. This seriously slows it down.
So I used the go/done flag instead and this improved things by a factor of 2.5.
I found in the end the sampling rate was too slow and this caused the steps.
I turned down sampling steps to 1 and the steps disappeared.
So getting much more sampling rate out of PIC than they say I can or recommend.
Probably good for 100KHZ wave at best so good enough for audio or sub 100KHz square waves.
I have 2 other designs which go much faster (17M/S and 22M/S) but they use external a2d's.
My grandson found an enya 15D-II ( small airplace model diesel) missing needle.
As it has a ball bearing and old dried vegetable oil i dismounted it and cleaned the
body including ballbearing in a ultrasound cleaner. Reassemble and a drop of oil it's
ready for duty and a demonstration for next generation. Nice when young people picks
up older technology by curiosity.
As it has a ball bearing and old dried vegetable oil i dismounted it and cleaned the
body including ballbearing in a ultrasound cleaner. Reassemble and a drop of oil it's
ready for duty and a demonstration for next generation. Nice when young people picks
up older technology by curiosity.
Hi Nigel,
Honestly, that can't be a surprise. Using the microcontroller for A-D will expose you to all kinds of timing or sampling issues. You never know when the micro is going to go ahead and do something else.
So the external A-Ds will allow you to control the sampling rate, and you will know what it is for sure. It just seems safer to rely on this than having issues with the system after an innocent software change.
I had a preamp for sale on consignment. A "customer" not only ripped the ground shield off on a jack, and almost another, he messed around with the internal adjustments! Because this was a Counterpoint SA-3000, that means a difficult jack quad replacement (I was lucky to have one the same!), and the alignment process is very involved and time consuming. One idiot cost me about $320 in parts and labour time. I am upset the guy selling it exposed me to this kind of expense, and he is a friend. But because the idiot was a friend of my friend, I got ... well, took the loss between the eyes.
Sent him a pointed email. I may have to sell things myself, but I hate doing that. It isn't what I do. I am pretty upset about it. I shouldn't be on the hook for the actions of someone else.
-Chris
Honestly, that can't be a surprise. Using the microcontroller for A-D will expose you to all kinds of timing or sampling issues. You never know when the micro is going to go ahead and do something else.
So the external A-Ds will allow you to control the sampling rate, and you will know what it is for sure. It just seems safer to rely on this than having issues with the system after an innocent software change.
I had a preamp for sale on consignment. A "customer" not only ripped the ground shield off on a jack, and almost another, he messed around with the internal adjustments! Because this was a Counterpoint SA-3000, that means a difficult jack quad replacement (I was lucky to have one the same!), and the alignment process is very involved and time consuming. One idiot cost me about $320 in parts and labour time. I am upset the guy selling it exposed me to this kind of expense, and he is a friend. But because the idiot was a friend of my friend, I got ... well, took the loss between the eyes.
Sent him a pointed email. I may have to sell things myself, but I hate doing that. It isn't what I do. I am pretty upset about it. I shouldn't be on the hook for the actions of someone else.
-Chris
Hi,
Thank you.
Yeah, that is probably what happened. But this is the last time.
You're right, I think the friendships are confused. I do a lot of service work for this guy and I feel abused big time. I do his high end work. I just blanket refused to look at any more repairs he had in other places recently. I am so sick of doing cleanup work.
Thank you.
Yeah, that is probably what happened. But this is the last time.
You're right, I think the friendships are confused. I do a lot of service work for this guy and I feel abused big time. I do his high end work. I just blanket refused to look at any more repairs he had in other places recently. I am so sick of doing cleanup work.
You can be swamped, and not have time for at least a couple of months.
And have no room to store it until then.
Some years ago, a good customer bought a pair of used Luxman MB3045 amps.
After a year or two, the cathode follower stage in one amp burst into flame,
and ruined the pcb. I disassembled the amp, removed the pcb (which has tons
of wires soldered to it), and designed and built up a new replacement pcb.
After reassembly, the amp worked fine. I did this for free, because he was a good customer,
and a friend. But I would never have considered doing this for someone who had tried to
unfairly take advantage of me in some way. Certainly not like you mentioned.
You have to draw a line somewhere, and I have had to do that a number of times.
And have no room to store it until then.
Some years ago, a good customer bought a pair of used Luxman MB3045 amps.
After a year or two, the cathode follower stage in one amp burst into flame,
and ruined the pcb. I disassembled the amp, removed the pcb (which has tons
of wires soldered to it), and designed and built up a new replacement pcb.
After reassembly, the amp worked fine. I did this for free, because he was a good customer,
and a friend. But I would never have considered doing this for someone who had tried to
unfairly take advantage of me in some way. Certainly not like you mentioned.
You have to draw a line somewhere, and I have had to do that a number of times.
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