I suppose by now everyone is wondering what has happened to the 6L6 SE-UL amp project. Well, so am I. Kind of.
As I said back in early August, there were a whole bunch of other tasks that were taking my time. Well, we finished the roofing project on September 2nd. The hidden fastener, standing seam, metal roof looks great. And most of my summer canning projects are behind me. So I went and got my new spray paint and had a go at finally getting the amp top painted. The finish did not turn out acceptably. In fact, not just “not acceptable” but a truly “terrible, horrible, no good, very bad” finish (à la Judith Viorst).
So I will be letting the paint cure for at least a week, buffing it out, and seeing about applying a different finish. This process has been exceptionally aggravating. And some investigations into paints and currently allowed solvents are leading me to believe that the US EPA is on a mission to destroy any and all convenient consumer finishing products. In fact, I have just about convinced myself that all future amp tops will be done through Front Panel Express just to avoid the frustration.
I’m sure that I’ll get it done soon. And when I do, the final assembly and testing should occur in rapid succession. Unlike many of my amplifier projects, this one has a home even before it’s finished, so I need to get it done.
As always, questions and comments are welcome.
13 September: A Quick Note
Do you see up there in the second paragraph where I said “And most of my summer canning projects are behind me”? Well, over the last two days I’ve put up 44 Jars of plums (Italian Prunes actually). That’s 5 quart jars and 23 1-1/2 pint (24oz) jars of plums in light syrup and 16 1-1/2 pint (24oz) jars of spiced plum halves. And I still have to put up about 7 quarts of fruit pie filing from the box of apples sitting in the kitchen. So there’s still some work to do getting ready for winter. But I’ll get back to the amp soon.
I was happy to see a post in the blog, but I was sad to hear that you are having more paint problems. Hopefully, final assemble goes more smoothly.
Yes still very busy. I spent most of today plotting stud lines and pre staining tongue & groove cedar siding. Need to get the exterior finished before the rainy season hits.
Final assembly should be a picnic compared to the paint. 😉
Hopefully you are making progress on the paint. Having done auto projects, my two cents is chassis paint or engine paint since you are doing satin black. However, because the paint is thick, it may close up the holes you drilled and require you to ream them out. In any case, I am looking forward to seeing if your goal of KT88s is achievable.
I think I’m going to try your suggestion. We’ll see how it goes.
Right now I’m taking advantage of our dry mild weather to get some outdoor projects done. When the rain starts up in earnest here, I’ll be moving inside and be back to amp work almost full time.
This question is a little off topic, but I have seen your 2-part article on tube power supplies and know you have thought about the topic a lot. I was just curious about your opinion of voltage dividers in the power supply to protect tubes at start up. I am also curious about your feeling about thermistors for the same issue. It might be a blog post while we are waiting for rain to start or for paint to dry. Thanks!
Actually home powder coating IS a viable option. The Amp chassis parts are small enough to fit in a standard home size stove/oven, I picked one up for just powder coating used for about $50.00 (you probably don’t want to use the oven you cook food in). The powder coating gun kit from Eastwood is about $150.00 and you need a small air compressor (only low psi is needed). The powder is also relatively inexpensive $15 to $25 depending on color and that should do several Amps. And I was surprised how easy powder coating is to do. My first try was successful. No fumes, Its fast (less time than it takes spray enamel to dry) very little cleanup, and the finish is amazingly durable. I built a small plywood box from plywood scraps about 3′ X 2′ X 2′ for a powder coating “booth”. The powder goes everywhere without this. My booth has 1.5″X1.5″ metal angle “slides” that the oven rack sits on while I spray the powder, the parts to be painted hang from the oven rack with wires, then I just slide the rack with parts out of the booth and into the oven for baking the powder, then after baking back into the booth for cooling. The metal slides also act as a ground conductor for the powder coat gun.
I’ve thought about doing this but the thing that always stops me is space. I figure I need about 20 square feet of floor space for the oven, spray cabinet, materials, storage, etc. And I just don’t have that available in my workshop. If I had an outbuilding, I’d do it in a minute. But I am space constrained to the point of stacking things on top of one another in my workshop.
Maybe stack the spray booth over the oven? (Deactivate the cook top burners) would only take up the floor space of the oven then. Just a thought.
Yep, the EPA (for better or worse) is clamping down on VOC’s like never before. Here in Pennsylvania, you ought to see the kind of air filtering required of pro paint shops (pros still use the “good stuff”) But this is probably the reason powder coating is taking over – virtually no fumes.
Front Panel Express seems like the wise choice. You design and draw, they build to your specs.