Saturday, July 4, 2020

Additional Horsepower

When starting out in woodworking, most think they will never be able to afford all the tools they need/want/desire. But with patience, and the accumulation of years, the gaps fill to a point where, at least I don't feel limited by the tool set I have. In some cases, that means that while I might have multiples of some things (shiny planes & shaves) I might be missing some basic functionality that many others assume as first rung tool ladder purchases (power miter saw, plunge base router). I often find it surprising to compare tools with other woodworkers, and find we often have odd gaps where our tool paths diverged either from specialty, ethics (power/hand), space, or finances.

This is a long way to say I don't have sawhorses. I've never owned them. Whenever I needed them I had always somehow made do with some other temporary support and thought "I should get some saw horses" and then do nothing until the next time they would be handy... Of course there are numerous great designs (intrigued with the knock down burro design,) and they can even be purchased, but that all seemed like something I'd get to someday, but never did.

What I did have was a crazy PVC pipe monstrosity. This bulky, ugly cage was something I knocked together a couple of years ago when I was enamored by the material and I was getting into Gymnastic Strength Training. I made this contraption to do parallel bar dips. I never really liked it, but figured, "no problem, I'll be up to using rings for everything in no time!" Narrator: He did not quickly progress to rings. (Rings are hard). While I do hope to get fully on to those ring progressions, I finally decided the cage had to go and I needed something better. I landed on Krenovian parallel bars.

To be honest, I had not really liked the design before. They always seemed a bit too precious and complicated and light duty for the somewhat rough, disposable nature of sawhorses (though certainly not the most complicated I've seen) Still, I landed on them because of the lack of protuberances in the undercarriage interfering with their (or rather my) action.  I also admit they look nicely stored away, and would certainly match my emerging shop vibe once burned "finished".

While I'm pretty sure I could have come made them from memory, or customizing based on an image search, I recalled an old Fine Woodworking article on the topic. I found the one I was after (with of course some time rummaging through adjacent articles as one does when going through FWW) and found the one I remembered.

It was by Anissa Kapsales I didn't recall this fact, in fact at the time I read this originally, I didn't "know" her at all. If you don't, she is a delight and adds a lot of fun to Shop Talk Live podcast which is a must listen if you are this far into this post and not bored to tears. I got no little kick out of this,  it was like finding out the interesting person you met as an adult, actually was in your high school and you just hadn't known them then.

I did make a few alterations to the design; it seems the designer had prioritized their function as sawhorses over gymnastic parallel bars, weird. This would not do for me, but I did compromise and make them a little shorter than initially planned so they can (with a simple plywood top panel) also stand in as out feed support for my table saw. (Yeah, the irony of another simple thing that I've somehow avoided) I also raised the lower stretcher a bit to better balance the split and to align with my saw bench height. I used some different thicknesses based on scraps I already had on hand, and I rounded the top edges and added an angle cut to tweak the feel/look to taste.

draw bore pegsNow that I've completed the pair, I have a newfound appreciation for their design. They are pretty smart, a functional tutorial along the lines of a traditional bench sawhook that is slightly more complicated than it needs to be, but has benefits beyond its intended function. Heres why; in building a pair, a new woodworker would make 4 blind mortise and tenon joints (I draw bored mine), 4 through wedged M&T joints and 4 (pinned) lap type joints. This is all in the context of very economical material usage that really can be made from short odd scraps in a variety of thicknesses that I almost guarantee you already have on hand. This is an ideal project for someone new to joinery looking for practice in a project with some leeway on the end result.

Beyond the simple project that packs a lot of learning in, Krenov's design reminded me about one of the goals I'd hoped to achieve with this blog.

It's hard to believe that in the seven-ish years I've been occasionally blogging, I've never really discussed what I may be most qualified to talk on. In my secular job, my expertise, such as it is, is in the field of engineering, applying and analyzing geometric dimensioning & tolerancing (GD&T). In this realm, there are numerous problems that engineers often try to solve by over constraining a design (think, wobbly 4 legged table vs stable tripod) sometimes it's obvious, but unavoidable, sometimes it's less obvious but by taking a constraint theory approach to looking at the system, the root cause of the problem (and often then the solution) emerges.

I've often thought that woodworkers have had to deal with and apply constraint theory problems over the ages (with the corollary that due to the constant wood movement changing the dimensions of parts, it is a lesson that must be learned) Many vernacular designs I have observed have (un)knowingly have addressed these constraint problems. For instance, a four legged table with a normal apron structure, the top normally has enough flex and will "hinge" across the high corners resting easily on all four legs, but an excessively stiff undercarriage will not give in this manner, introducing the dreaded wobble.

These sawhorses similarly are a light frame that is easily warped/twisted which could seem flimsy in that direction but actually will allow the four legs to rest on an irregular surface. With a load applied these easily accommodated one leg on a ¾" horse stall mat. The wedged/pinned joints will hold tight through any induced flexing of the structure, which the hardwood (oak in my case) can likewise absorb. The cutouts in the sled feet make this flexing all the more possible allowing solid ground contact, with any downward force applied. And the direction that force is applied it is incredibly strong for its weight, since the upright is directly inline with the applied force. The narrow body and unobtrusive feet are other definite advantages to the design.

Overall these Sawhorses parallel bars will be a nice addition to my space. and I wish I hadn't waited so long to make some, it was a good fun quick project that uses very little material and doesn't take up much space when completed. I hope this inspires you to make a pair, as I think they would be at home in a shop/gym, (unless you are already progressed to using just rings, in which case I hate you and hope you rot :)

Monday, December 16, 2019

It’s All Fun & Games (part 3)


You've tuned into the exciting conclusion!
(Recap: part 1 and part 2)
[skip intro]

This cabinet does not fit with my normal methods. Sheet goods, not much joinery, mostly painted and quick construction. (Insert self deprecating joke here.) Still, there were some things I was worried about, and worked out prior to construction, so I started with a (gasp) drawing. I share this information here not because this is the direction I intend to take this blog (so regular readers might skip this long post), but just in case anyone in the arcade cabinet community later finds something they'd like to borrow, I'd like to provide that resource and encouragement for them to do so.

Control Boxes


We started with the center control box because that was the part the boy needed completed for his assignment (Phase 1). The most fun part; don't do this part first or else everything will have to be made to fit around this, making the cabinet much more challenging to dial in perfectly, rather than just fitting the control box ±1/16" to fit the cabinet.... Or perhaps you should do this part first and stop there, because you have everything you really need to start having fun and the rest is a lot of work for what amounts to a fancy stand for this box.


The concept for these boxes revolves around modified traditional Japanese carpenter boxes, which are pretty genius in their design & construction. Simple, bomb proof, clever and require no hardware, yet provides access to controls if you need to get at them later. By angling the top, I made it a bit more complicated, as did the angled end surface for P3/P4. There was some order of operations and head scratching to make sure I got surfaces flush and the angles all correct (thanks high school geometry!, also block plane) This was especially the case with the tapered dovetail connection to lock the boxes together, but that's mostly a game of what shape goes where (see pictures) rather than any ubercomplicated joinery.

  

I glue the long grain joints where I can for strength, and since we charred the surface as the finish, we carefully finished all visible surfaces prior to glue/assembly. Simple finish pin nails (screws on the lid batons) and it comes together easily and sturdily.

(Tip: the hole for the locking pin gets drilled at the very very end)

Carcass Construction


Most arcade cabinets are made with MDF, which is a fine enough material for it's purpose, and especially given the vinyl/paint finish applied is a good fit. Despite MDF's lower cost; it's also heavier, and has a tendency to not wear as well long term when moving, plus I prefer working with plywood, so that's what I went with instead. I did as best as I could with sizing components (e.g. sides are <1/2 sheet width); I still ended up needing 3 sheets to get all the major components. (Exact quantities are not 100% clear since I have lots of pre-existing scraps in my bins that we utilized where we could.) We used 3/4" "Classic Birch", which is marginally better than paint grade BCX plywood (additional ply's and a slightly smoother surface), but it's not great plywood. (Tho' this aint fine furniture either.) In retrospect, I think I would have preferred to use 1/2" at least for the middle panels to cut some weight.
Most MDF cabinets also call for T-molding to cushion/round the edges and give a more finished edge. I chose not to, to save some expense (mostly from needing a specialized router bit to go around curved edges) this meant a simple round over, filling and sanding. T-molding would probably be nicer, but I'm not unhappy with the results and an acceptable way to cut costs if using plywood.

I'm sure there are several ways to put this together, we used glue & pocket screws spaced fairly close together. Then fill all the pocket holes with shop made plugs The most challenging bits are aligning the parts during assembly. Draw a line to show the reveal, then use clamps provide a stop so the piece doesn't shift while driving the screws. It's plenty solid especially once the "drawer" is added. 

The Big Drawer


Possibly this is the part you should start with, then the carcass, then the control panel to reduce the impact any errors might have. I did it last... It's a pretty straightforward (and hidden) pocket screwed frame with plywood shelves mounted on drawer slides. I originally intended to have stops & latches attached; but in practice it moves with just enough friction, but not too freely... lethargy wins again.

Getting Curved


If there was one thing I'm not sure of, it was using regular plywood and kerfing/bending  it to follow the line. It worked, but did create facets and personal stress during the process. The boy likes the facets, so I guess I like that about it, though a smooth curve from bending plywood or veneer over ribs seems like a better choice to me (I couldn't get bendy ply in a timely manner, so that drove the decision)

What I did learn about this process is:
  • This kerfing calculator is pretty accurate, though I felt like we needed an additional cut or two from it's suggested value. Do a few test runs on scrap.
  • The kerf show face will be dangerously thin to prevent splintering when bending. This is a problem when manhandling a nearly full sheet of plywood.
  • We utilized a T-square Circ saw jig since my rip fence wasn't wide enough to do all the cuts on the Table saw.
  • We used Polyurethane glue in the kerfs to provide a paintable gap fill with the expanding foam. This kind of worked (required some cleanup chisel work) but would have been better to just use paintable caulk afterwards

Electronics

There are many resources for electronics setup with the retropie setup, so I won't go into great detail. I will just highlight a couple of things I didn't know about.

I stressed about snap-in vs. screw buttons. A clean hole from a correctly sized carbide forstner bit (highly recomended) and the widely available snap-in will be just fine in 3/4 wood. Normal use pushes them tight into the hole so they won't pop out, and since this isn't a public arcade, I'm not worried about vandals prying them up from the top surface. It's literally fine.

I was worried that given the increased depth of the wood top panel, the joystick would need extensions. I tried them, it's better without. They aren't required at 3/4" thickness.

Inside the main box, I found it useful to snake a few extension cords for USB/HDMI/power through the exterior. This makes final connections easy. I recessed the ports and hot glued them in. It's a nice feature and makes the central unit feel much more polished than other possible solutions.

I was originally going to wire this cabinet up with the traditional socket and switch, but found a simple power strip (with longish cord) on the top shelf is hidden and fine. The cabinet construction lets you snake the power cord out easily. Then TV, Raspberry pie etc. plugs into that.
When wiring up the USB controllers, get them wired to the controls FIRST, then mount it to the box based on wire slack available. Speaking of mounting the control PCB's ...Hot melt glue is fine, like we did on the first two... but use the low temp little guns, not the upgraded hi temp gun I bought mid project and fried P3 & P4 the first time and need replacements. 

Painting

It's painted. I dislike painting, but you probably already have an opinion on that. Trim everything, fill everything, lightly sand everything, prime (always Zinsser BIN), paint it how you want.


The Plans



A few things changed from the rough drawings outlined here, hopefully they will be obvious as you see in the construction photos or read above. but these are here for reference for those that benefit from numbers.

Most notable change is, there was originally a bezel that was to give some structure and mount the TV Panel to. In the end, I found the construction to be solid and it wasn't needed, so I simplified the TV mount to an articulated VESA arm, which allows re-positioning when converting 2p to 4p. The back and top are all one piece not two as shown in the drawing.  Also, originally I had ribs to support the curved top. These aren't needed given the way I constructed it., Had I used a thinner more flexible part, maybe it would.

This was a great project. We've had many good moments at this machine. It was great to work with my son on a project that we both can enjoy both from the time spent working together on it, as well as the time spent together at the controls. I hope there are many more beyond this one.






Friday, December 13, 2019

It’s All Fun & Games (part 2)

 When the boy expressed an interest in building an arcade cabinet (See exciting backstory in part 1), I was largely disinterested, because they seemed to be large and uninteresting boxes at first glance. And not to try to offend anyone, but often they are garish and clash with almost everything decor wise outside of the over stimulated atmosphere of a dimly lit arcade of days gone by. As a single father of two teens, I'm pretty sure Architectural Digest isn't swinging by for a photo shoot anytime soon, but still many arcade cabinets are just plain ugly, clunky and absolutely HUGE. Still, I wanted to support his interest and so I began delving into numerous designs so I could help guide his choices into something I'd be OK with being in my house, and would be fun to play together.

Form


One design decision that needed sorted was form factor. There are 3 main types: Free standing cabinet, table top, and Arcade-in-a-box.

Arcade in a box (with HDMI out to TV) seemed like an interesting idea plus would be portable if wanting to take it to friends houses, playing on the projector etc. But unfortunately I think this would miss out on some of the best things about arcade style controls, i.e.  the jostling that ensues from competitive proximity in 2P games and being able to lean into the joystick and buttons with a bit of solidity. The later also ruled out the table top style for me, (That and the fact that it would still need stored someplace largish or take up table/counter space.) This steered us to a free standing cabinet. Traditional freestanding cabinets are very deep some ~40" deep.

Style


One other major design choice is whether you are going for authentic with tube monitors bezels etc or not. That will drive excessive depth and extra electronics, and that we were going for a vibe rather than authenticity, we decided we would veer from traditional shapes. We were both rather impressed by the shape of this one, and used it liberally for inspiration. I was mostly impressed with the round top as it sort of lent a modern, minimal take to the side profile to my eyes, but there are many many options for shapes to consider to get a shape that looks right to you. In the end utilizing a modern flat panel allowed for the unit to be significantly less deep (24") and could be smaller still if desired, though at some point it gets tippy, which is why we chose a more square corner at the bottom.
(Honorable mention goes to an idea to incorporate a TARDIS MAME cabinet, something else we both wanted to make, but in the end it fell away)

Controls



Another major design step is determining control layout. In an arcade, there are many setups and controls optimized for each specific game. With a MAME cabinet, trying to incorporate all of them (knobs, balls, joysticks, buttons ...) often leads to the strange, cool and weird. One major decision point is the number of players. We eliminated single player from the choices since so many of our favorite games involve cooperative/competitive play. There are many interesting 4 player games, but allowing space for the panel starts to make for a very large unit. At some point we asked "what if it could convert from 2p to 4p mode?" and this is when inspiration struck, and where we had a chance to innovate in our design. 

There are some others out there with modular controls in their cabinet (It's very cool to explore what other creative people come up with) but as far as I know no others that transform in quite the same way as ours, with a removable arcade in a box style that has attachable "wings" for P3 & P4. This also necessitated a pull-out "drawer" to allow the cabinet to convert so the wings can attach. This project began taking on a life of it's own beyond what the boy could complete for the project, but it was also pulling in my interest for doing interesting things.

Hardware


Arcade memories are interesting. I found I had distinct memories of how things were, even though after researching you find out you are mixing memories. I love the uber-clicky Happ buttons, but also the convex button shape (false memory) I also like the ball type Sanwa joysticks over baton Happ joysticks (you might have your opinion, this is mine) in the end I got some super clicky buttons for "Start" buttons to scratch that itch, but went with the Sanwa type buttons/joystick elsewhere (they still have a nice enough "click") it pays to do some reading about the mechanical differences

Button layout is another highly personal choice. There are some great resources to consider. We decided to go full 8 button layout but no roller balls or other odd bits, just because we didn't think we'd need them often enough to justify (though centipede would be fun.) This is what I decided, with some minor tweaks to make P3 & P4 to make things work either visually or mechanically. This pattern fans out nicely under my fingers and doesn't cause weird reach issues.

Finishes



Many cabinets are very flashy and colorful, which is at home in an arcade but not in many homes and comes off as an eyesore to many. We liked the monochrome effect in the referenced design as well as the character representation used. To be honest, we have another phase "planned" that would involve a similar custom combination of heroes (and villains on the opposing side) but given how happy we are with it as-is it is unlikely this design and painting will ever come to fruition.

The control panel is another thing that takes a lot of abuse and I've seen vinyl coated MDF versions worn quickly or metal or plastic versions, but I'm a creature of habit when it comes to materials (preferring wood), so I guess it's not really surprising that I ended up with a Shousugiban (technically Yakisugi) oak panel. I love the tactility it adds to projects which makes it perfect for this area of the machine. I think it also classes it up a bit. For similar reasons, we also chose low key black buttons (without any lights) for one row of buttons, to avoid the "too many buttons" look.

Design Conclusion


In the end we came to this design, it's worked out extremely well. I think if I was starting over, I might consider a wall cabinet version hung on a french cleat) just to further reduce the footprint, but it's good. Also, theory vs. reality lesson learned, I could have probably used fewer buttons on P3, P4 since 4p games never support that many buttons, but #symmetry... One other design feature that I had in my design but never executed (but may eventually get around to retrofitting) is 2 skateboard wheels in the back corners to allow it to tilt & roll since it's kind of hard to move.











Tuesday, September 24, 2019

It’s All Fun & Games (part 1)

This year my son started high school... 9th grade. You might recall that my daughter made a music stand for her 8th grade art project. and think that I didn’t help with his project...well a slacker I may often be, but not here. As is often the case, it morphed into a huge multi-phase project that took ages & ages to complete. Since I tend to only blog about projects when they are done (notice the lack of blogging...) here we are. I’m going to split this post into 3 sections (with design considerations and construction) being in their own page just to make it bearable for whatever audience this may find.

If you know this kid, or stalk me and my family via this blog, you know that he's into all things gaming, with a fondness for retro video games, so it's no surprise he chose to do something related. Initially, I was hesitant to support this, since I'm usually trying to get him to spend less time in front of a screen, not more; but after we worked out some of the designs, it seemed like a great art project, a way to learn more about programming, electronics, and woodworking. And in the end we'd have something that would fit with the current "bachelor pad" that is my life.

This project was an absolute success, we completed the main arcade-in-a-box center section in time for his project deadline nearly a year (!) ago (and got a much deserved A+). He certainly put in the time and effort on this one and was engaged well into the more challenging later phases. He was able to also showcase this project later in his computer programming class, and even at the state capitol for a young people and technology display. This was an excellent foray into woodworking, power tools and making things. We spent a lot of time together, just chatting and perhaps planting seeds for future projects when the desire takes shape.

Of course we had the shared experience of working together, but I've also found that the nature of these arcade cabinets is that they encourage socially playing together for "just one game" together that may stretch into a raucous competitive good hour. We've reconnected to classic games from my youth and some crazy "new" ones neither of us has played before. All these moments add up to a full relationship. Once again, I am reminded of just how important it is to actively do things WITH your kids and not just FOR them (big difference between playing alongside vs. delivering/watching them play with other kids.) Sometimes you do this for the practical value of things they will learn in the process and carry with them, sometimes to show them that they are capable of accomplishing great things, and sometimes because there will be shared memories and inside jokes that develop your relationship beyond "parental unit" and "offspring."