My Bandsaw Circle Jig actually started out as an idea for a disk sander jig I saw in one of my woodworking magazines. They used a sliding arm with a screw adjuster to fine tune the diameter of the circle. I thought this was neat and it slowly evolved into the arm I made for my bandsaw jig.
I already had an arm with T-slot track in it from the bandsaw project, so I figured that would get used in both jigs. You could cut on the bandsaw, then fine tune on the disk sander. The construction method I used before applies well here too. 3D print a runner to go in the miter slot, start with a base of 1/4″ MDF, then attach 3/4″ MDF on top to guide the sliding arm. I CA glued the runner in place with it all aligned, and then screwed it in from underneath.
I don’t have any features to keep the adjustment arm locked down because the disk sander’s movement should push the work piece into the table and keep it stable. Hopefully that theory continues to work out for me.
The new thing here is the adjuster. The wood magazine had something with a T-nut and bolt. It was fine, but I figured a printer could do better. The knobs were something I had designed earlier. Each holds a 1/4″-20 coupling nut. The adjustment screw is a bit of threaded rod with a coupling nut bonded to one side. The other was rounded via a drill and bench grinder. The knob will glue on to the nut and the rounded end will push up against a hard stop. Having it rounded should mean there is only point contact and will make for smoother more even adjustment.
The adjuster uses a bolt in the t-track of the adjustment arm to clamp itself down in the rough position. I added a block to the bottom of the jig and bonded a big fender washer down for the head of the adjustment screw to contact. It should be a very firm stop and won’t wear easily.
Putting it all together, and with a few coats of polyurethane to keep the MDF stable, I tested it with another sharpening wheel. My last one was a little small, so I made a new bigger thicker one. The only thing to note is that doing heavy sanding in one spot will load up the paper badly. Sliding down the table occasionally will help even out the wear.
I have a router circle cutting jig from milescraft that works pretty well. It screws down a center and uses your router on an adjustable arm to make big circles. It does take a bit of setup though, and anything under about a foot in diameter is pretty awkward. There are loads of bandsaw jig ideas, so why not add mine to the pile? I think I have three things that are slightly unique in this design. Not revolutionary, but a bit different.
1. I started with a 3D printed miter slot runner. It is T shaped so once you slide it in the jig can’t come up off the table. Most folks make wood runners. Those are fine, but with printing it is a lot easier to dial in a T-slot so that the jig can’t lift. It comes with countersinks for #6 mounting screws.
2. The jig needs some kind of sliding arm to hold the piece being circle cut and set the circle radius. Dovetail slots and all sorts of things are employed. I took a T-track and glued it into a piece of 3/4″ MDF. Even 1/2″ screws would have been too long, so I just used epoxy. It holds well. A look from underneath shows that a bolt and knob let you lock down the circle radius arm in position.
3. To hold the work piece, most jigs use a small nail sticking up from the adjuster arm. You would drill a small hole in the part and pin it on the nail in the jig. Instead, I wanted a more flexible solution. I cut a 1-1/4″ hold in the end of my adjustment arm so I could put in 3D printed holders. One is 1/2″ in diameter so I can cut a MDF circle for my buffer. The other has a countersunk hole so I can screw a small #6 screw into the work piece. Optionally, there is enough space there to double sticky tape the puck down and use the center hole for alignment. I can print all sorts of posts or pins to suit my cutting needs.
To put that all together, a piece of 1/4″ MDF was CA glued to the runner (temporary) and pushed into the saw till it reached the middle of the jig. I glued a little stop in front so it would hit the bandsaw bed and stop in the same place every time. I then glued on 3/4″ MDF around the centered adjustment arm. That gave me enough material to screw on, from underneath, the glued runner. That all got pushed in again to the saw to cut through the new 3/4″ MDF.
I did some measuring, marked our the rough radius locations, and coated everything in a few coats of thinned polyurethane. It struggles a bit with anything under a few inches in radius, but a different blade would help. Up to 2 foot circles are possible. Above that and I will go to the router jig. To try it out, I made a sharpening wheel for my buffer out of 3/4″ MDF.
Set the runner to the appropriate radius and lock the knob
Install the square of material to be cut on the peg
I haven’t done a print grab bag in ages and realized I had a pile of fun and useful prints bouncing around. Let a montage of 3D printed goodness begin!
Not super original, you can find a zillion of these online, but I wanted my own. First up, they are nice and big for me to read, and secondly, there is always something you have that isn’t in the list given online. The first set were just white with black paint marker coloring. I later started doing batches and swapping to black on the right Z layer to make the lettering pop.
I always keep a big exacto blade and a few deburring tools around in my shop. They tended to float on my messy table top and get lost (part of the reason I have two deburring tools). In an effort to keep that area clean I made a tool holder that screws to the underside of the shelf. Previously unused space now keeps me better organized. It tilts back 10 degrees to keep them from vibrating out when I slam the door on that wall. No unexpected falling knives please!
Sticking with the shop theme, I have a supply of semi-disposable items I always keep around. Popsicle sticks of various sizes and acid brushes are really useful for mixing, spreading or applying different substances. I used to keep them in loose piles or cups, but now I have a custom dispenser for each.
The basic design is the same in all, but with some modification to dimensions depending on what was being dispensed. The front wall slides in and has custom text for each one. A lid keeps the dust out and allows stacking. I printed them with 5% gyroidal infill and a hole in the bottom. That let me use sand to add weight, capping with epoxy. I have been using this trick a lot lately and love doing it. I used hot glue on the bottoms of each, then smashed it down on a silicone mat to make quick non-skid bottoms. The weight from the sand and the non-skid bottoms keep them from moving around easily. You wouldn’t want them to fall off the high shelf they are on.
Shark Bite Remover
Shark bite fittings are a great plumbing invention. They fit over the 1/2″ cpvc plumbing in my house and mean the fittings can be replaced without cutting the pipe. I had a supply valve go bad in one location, and wanted to switch orientations in another location. No cutting required! The trick is, getting them off is a beast. You have to push in on the release sleeve, twist and pull. All while being gentle and not stressing the pipes too much. They sell little C clips to make it easier, but I lose them and they aren’t comfortable on your fingers. Enter some printed ones.
I printed LOTS of these and sprinkled them throughout my plumbing supplies. They have more finger surface than the store bought ones, so you can get a better grip. Plus they are thinner. I found myself having to replace a fitting that didn’t have much pipe sticking out. These thin ones got in there, the store bought wouldn’t fit.
Moving from the shop into the house, my wife has been playing chess a lot recently. She wanted a chess set so I made one out of sparkly galaxy black filament and marble filament. I printed each one hollow, filled with sand, and capped with epoxy. The board is a set of 4 tiles printed with a color change from black to white. I put it all on a piece of MDF. That part wasn’t brilliant. I started with black polyurethane then tried to move on to spray paint. I still don’t have a good MDF painting technique apparently. The edges endlessly suck up what ever you put down. That part will probably get remade at a later date.
To hold all the chess pieces I made a box with sliding lid. The fit is good enough that it kind of blends in when fully assembled. Embossed along the sides are a symbol of each chess piece type.
This moon lamp design comes in many flavors online. Thingiverse My implementation isn’t that unique. I did copy the spline shape used to attach the moon, and made my own base to hold the bulb. The base was once again filled with sand and capped. Now the lamp is quite hefty. The main challenge of this job was that the moon print took about 3 days. I accidentally interrupted one attempt when it was 90% complete… oops. The base is 6.5″ in diameter and the moon a little over 8″.
Monitor Picture Holder
Last but certainly not least, I got this cool frame for fathers day. I wanted to keep it close by, and for some reason the top of my monitor jumped out at me as the perfect location. A simple print later, and there was a perfect space for the frame to sit. The little guy is always on my mind, and now always on my monitor.
I have been working on this project slowly in the background since probably October. Early on, I was unable to finish printing the parts because of a mysterious heat creep issue. After a few months I had that sorted, and went on to figuring out how to smooth my prints. That went through a few iterations, then it was on to painting. Lots of trial and error, but with really good final results. Over this project I learned a lot about the hot end of my printer, came up with a new-to-me smoothing technique, and picked up an airbrush and taught myself to use it.
My first challenge was to smooth out the prints. The head came in 3 parts and I decided to smooth each one individually, then glue them together. Probably would have gone better the other way as we shall see. I spent a lot of time with sanding sponges, power tools and air erasers. Nothing worked well to bring down the surface roughness. My printer issues were really starting to bite me. I hit upon an idea with epoxy coating. They make special two part epoxies for over-coating FDM prints. I figured a slow two part I already had available was probably good enough. Below is one of my tests. Left side bare, right side coated.
Two part epoxy works well, but has a few draw backs. You tend to have to mix big batches, then really get working once they are cooking. It adheres well and is thick enough to hide most layer lines. Drips are an issue and once you have it in place, it can run and sag till the stuff starts to kick off. It was way better than endlessly sanding and priming, but still had some issues. Another test piece below.
I did some more research and found that printer resin is another possible option. I picked up a small bottle and a 405nm light and got to work. The results are great. It a good thickness as is, but can be thinned with IPA if desired. The trick is that you want to completely coat an area, then cure. Painting on more resin will make it hard to blend as the new stuff stays on top of the cured stuff. The resin has as much working time as you want, so you can take your time, go thin, then cure when you are ready. The part should be wiped down with a bit of IPA afterwards to clean up the sticky residue. The resin used below is black, but is transparent enough it is hard to see the effect.
With the major parts coated and smooth, I glued everything together. There was some bed warp, so I had major gaps to fill. I used bondo spot putty. It is hard to apply smoothly, and takes a bit of sanding to get flush. It sands much faster than the resin parts, so if you get too aggressive, you make valleys. Plus, resin doesn’t stick to it, so this part was pretty tricky. I need to find a better gap filling solution. UV resin won’t cure deep enough and is too thin.
I sanded and thought it all looked good, but the bondo still wasn’t smooth in spots.
You can’t hide anything once the primer goes down. That flat color shows all. After countless rounds of filling, sanding and re-priming I got it good enough. Next came the paint.
I am not much of an artist, and this is where I got out way over my skis. I had some basic craft paints, so I tried to make a bone color. The first was way too dark, and the second went on looking like streaky junk. My paint strokes were adding up and looking really awful.
Some peas for help on the internet got me the idea that I needed to try airbrushing. I had never done it before, but a basic cheap airbrush was about 40 bucks, and I already had the compressor. Plus, the cheap paints I was using had very little pigment. I went to slightly better craft paints that came in the color I wanted. The results were becoming much better.
Airbrush puts down a soft subtle amount of paint that you can easily add to. The acrylics were very matte, and that matched the bone look perfectly. After getting a base layer of everything down I went ahead and mixed a darker color for shadows.
After that I mixed white with a glossing agent and made the teeth whiter and shiner. It didn’t show as well as I had hoped, but the effect is still there a little in the end.
Lastly, I mixed up a really thin dirt color and started doing a weather/wash coat. I got a little carried away and the thing ended up being more dirty than I had originally set out to use. It was hard to stop though, it looked so cool. I spent extra time cleaning off the high spots and ridges so they looked a little polished, while the valleys were dirty.
I had the head and mouth parts complete, but needed a mounting plaque. I found a design on thingiverse someone made, but needed it a lot bigger. I cut the print into multiple parts. Instead of trying to glue them together and hide the seams, I taped them down to MDF, and used the print as a router template.
I used the slicer to cut off those raised bits, with a few alterations, and printed them separately to glue on later. They need to be smoothed, but I already had a plan for that. To keep them from getting to saggy or organic looking I used my airbrush to spray on the resin. It could be very thin and juuuuuust fill in the lines without breaking up any crisp edges. You have to make sure the fill job is good, once the primer goes on, resin won’t stick, so you have to fill and sand the rest of the way.
The MDF took paint like a thirsty beast. I eventually had to use bondo filler on the edges to seal them up.
Finally it got some silver spray paint with a few black brushes and accents. I am getting better at this whole painting thing! The head was glued down and hanging hardware added.
I have been watching this guy on youtube recently called Jigsaw Nation. He makes a lot of cool big signs out of plywood. Mostly car stuff, video games, and whatnot. I got inspired and decided to make a pair of NASA logos for my dad and I for Father’s day.
The jigsaw dude I follow projects onto the plywood and traces his designs out. I wanted to produce two of the same thing, so I opted to print a template and route instead. The AS was too big to print, so I cut it up into two parts with an alignment stitch between them. I doubled up the plywood and used my bandsaw to remove most of the waste. These letters are around 6 inches tall.
I went to the router table and ran into an issue. My pattern bit only has about an inch of cutting depth. Oops. I’ll have to split these up and do one set at a time.
I wanted these to look really clean and crisp, so I proceeded to use filler to make the edges solid and smooth. I tried mixing up goodfillas, plasticwood, and bondo spot filler. They each are kind of OK I guess. I didn’t end up taking pictures of that process because… can I still use the dad brain excuse? Same excuse for the background. It is a 2ft wide piece of plywood with the edges rounded and filled. For paint I did a number of coats of primer/filler to get it all as smooth as possible with sanding in between where needed.
I still need to work on my spray painting skills. I think I get going too thick and it leaves little puckers and attracts dust. When I go super light though I don’t see the gloss I want. Practice I suppose. To get the kerning right I printed the space between the N and A, and another between the S and A.
Once the glue was try I was all set. Dad was visiting at mother’s day and already has his hung up outside his rocket building control room. Mine is up high in my shop where the paint imperfections are hard to see!
My side table is a mess. It kind of always has been, but now I have a small one crawling around and yanking on every cable he finds. I can see a job as an electrician in his future. He loves wires! Here is the horror.
I can’t even bare to show the top side, it is not safe for the internet. In order to cleanup and keep my little guy safe from random power cords I started moving things to the underside of the table. The first step would be to anchor the power strip. Everything else would revolve around that. I measured the mounting hole spacing and made a drill template on the 3D printer.
Now I could start putting down wire anchors. Some of these are closed loops you can use with zip ties or velcro, others are open, and you can slip loops of wire into them. I designed my own, but lots of printed options are available online. I made a set of brackets to strap down my USB power brick. I will leave it under the table, and run the needed free lines around to the top.
As I was going, I realized I didn’t have anything for my laptop’s power brick. I found that velcro straps can make a quick flexible hold down if need be. Much faster and cheaper than printing something custom.
With the underside of the table taken care of I moved on to the top. General cleanup was in order. I wanted to consolidate as many things as possible into a single unit. This block will hold my weather station screen, has space for pens, roku remote, fan remote and echo dot. I printed it with 5% gyroid infill, filled everything with sand, and capped it with epoxy. Hot glue makes for thin grippy feet. Just squirt on the hot glue once it has gotten fully up to temp, smash the block down on a silicone glue mat. After a few when it is all cold the glue mat should peel off easily.
To help with all the speaker cables I made a box that slides around the backside of the sub-woofer. I screwed the speakers to the sides so they couldn’t be pulled out. The rear left and right speakers sit on the far side of our couches. Their wires are getting covers to keep them safe from small hands.
I screwed down some wire cover to the legs of the table. This gave me a place to run up and down the various power and connection cables I needed. The only free thing now is the audio cable between the echo dot and the speaker controller. I might either get a longer cable, or mount that to the underside of the table at some point in the future. The top looks pretty good now, and I have managed to keep it tidy for the last month. On to the next baby-proofing project!
My beloved Prusa is about to turn 4 years old. It has given me lots of years of good service with only a bit of maintenance and some minor upgrades. It is time to show it a little more love. While re-greasing all the bearings I decided to flatten the bed. Normally the bed warp is compensated for by the bed level probe. That is great, but it means the bottoms of your prints can be warped. The Mk3 printers have some simple upgrade using nylon lock nuts. The older printers are designed differently, so that isn’t an option. I do precision alignment professionally, so this should be easy.
First up, I used an octoprint plugin to see how flat my bed really is.
Gross. It is over 1.5mm off on the one corner. To fix this I am going to shim. The situation looks like this. Removable bed on top, heated bed under that, a standoff, then the metal frame. The heated bed and standoff are really tightly screwed together, the standoff was assembled to the metal frame when I built it.
I have brass washers from the hardware store. They turned out to be quite flat and 0.5mm thick. I will be slipping these in between the metal frame and the standoff one corner at a time, then re-testing my flatness.
I can’t drop my high spot, so I have to raise up the low spot to meet it. After adding shims one at a time to the low spots I got really confused. 1 washer added to the front left, made it go down. Also, the back looks flatter than before. I added a washer to the front right because I thought the scale was maybe reversed. It made the back worse!?! I am so confused.
I kept adding and removing washers and not understanding what was happening. I don’t know how it does these calculations and builds the maps, but I am completely confused. After an hour I found another plugin that is designed for the Mk3 nylock upgrade. I don’t have as many adjustment points, but it was still helpful.
According to this I was high on the right, ok in the center and front left, and low in the back left. I started adding shims to the whole setup based on this. Instead of slipping one in at a time I had to take the bed off to get to the center. I used super glue to hold the washers in place so they wouldn’t fall out during assembly.
This worked a lot better. My back right is still a little high, but I don’t have enough shims to continue. I might pick this up later and I can sand down the washers to be thinner if needed. For now though, this is pretty flat. I will avoid the far corner if possible. The other program shows it as being all high. I guess I don’t understand how it calculates 0. Maybe that was my main problem.
Did that do anything, or did I waste 2 hours of time? After all I have been printing for 4 years without it, and that is what a bed level sensor is for. I think it helped. Large prints come out flatter, and I can see that the z stages aren’t doing much compensation as they put down the first layer. For a little time and a modest cost in shims, this was an upgrade I wish I had done ages ago.
By the way, if you do this, 1ea 0.5mm washer was ok with the 8mm screw normally used. If you put in 2, you need a 10mm long screw. The fronts can be socket head cap screws, but the backs have to be button heads to clear the frame. Might want to pick some of those up if you plan on doing this job. I used brass washers for number 4 screws. Your mileage may vary.
First up, having a kid is not good for your project blog life. Good thing it is just a hobby and not a source of revenue! I got this one done during a few nap times.
I use these little 3 and 5oz dixie cups a lot around the shop. Uses include: holding screws/parts, mixing paints and epoxies, holding glue, filling and funneling stuff, etc. A lot of the time there are pop-sickle sticks and acid brushes sticking out of the cups, and they fall over. I was trying to paint 3d printer resin (cool post coming, eventually, about this) and my cup kept falling over. I finished my resin job and got to measuring the cups and making a solution.
The cups are different enough that each required its own holder. One turned out to be snugger than the other, but they both fit well enough to prevent tipping. I probably could have left it there, but went the extra mile. I printed two sets of each with no infill. I used the slicer to make a hole in the bottom to allow filling the hollow cavity.
I always keep a big bucket of sand around for filling objects to make them heavier and damp vibrations. These all got a fill of sand until there was only a small bit of space left. Next I mixed up a little slow cure epoxy and injected just enough to flow out of the hole. I wiped the entrance, tapped the hole with painters tape, then let them cure upright.
With the epoxy cured they make for really stable dependable holders. Next time I do one of these I will try one of the open infill patterns like gyroid. The gaps might be big enough for the sand to trickle through and infiltrate all the infill areas. It will likely take a lot of shaking, but it would make for a lot stronger part. Using pure epoxy would be easier, but the sand is such a cheap way to weight things like this down.
I haven’t done much in the way of projects since the arrival of our son. Life is by no means back to normal (nor will it ever be again), but I have managed to get enough free time while working on the wee one to get some printing done. I haven’t documented any of it for lack of time, but I want to get back to doing that. With my winter break I am going to do another round of printer maintenance and upgrades. This will help in that endeavor.
I went through a few clips till I found ones that would fit well inside the hose. I liked a smaller clip a little more, but getting it stuck int he nozzle properly was kind of a pain, so I went with the bigger ones. I could still make an adapter to hold different clips in the future.
I pulled off the orange nozzle tips and chamfered the entrance to help insert the clip base. I hammered it in, cross drilled a pilot hole through the hose side, and then screwed a small number 4 screw through to keep it all in place. The clips were pretty secure from the pressure fit, but the screw makes them really solid.
With the clips figured out, I needed a base. I printed a starfish looking pattern with a cavity underneath that holds the magnet. A short wood screw holds it in place. That adds weight to the base and will stick it down to a metal surface if need be. File on PrusaPrinters.
The hose base is some kind of 1/8″ pipe thread. It didn’t match the options I found on thingiverse, thus me making my own version. Instead of trying to match the tiny threads, I just made a slip fit and then screwed sideways through the hose base. Combine that with glue and all should be secure. To give myself little foot pads, I put more glue (E6000) on the bottom and sat it down on a silicone glue mat. Everything peeled right off the mat, and it made perfect little non-skid grippy pads.
A helping tower is like a step stool you use in the kitchen with a child. It gets them up to a height to be able to help out with basic cooking tasks. Unlike a basic step stool, this has sides and a back so they can be kept in place, and not easily fall off. There are a million different examples online, but most all of them are bulky (by necessity) and end up being a bit of an albatross in the kitchen. I wanted a folding one that could be packed away easily. It took a lot of prototyping, but I did it.
I normally jump into projects, but this one was a very slow methodical trial and error build over nearly 2 months. A broken AC and baby tasks stretched that out a bit. The front frame of the device consists of two permanent uprights with an upper and lower stretcher. To those uprights, a set of folding sides are attached. The right upright is thinner so that the two fold over each other in an overlapping pattern.
The middle stretcher will hold the step and let it swing into place. I needed a strong stop that would support the step and draw the sides into the step. I used a dovetail bit on the bottom of the step to make a slightly angled groove. The stops had the same angle in reverse. Now, the more weight put on the step, the tighter it will draw the sides in.
The seat can fold up and the sides fold in. Everything is compact and easy to deploy. The stops are only 1/2″ thick and don’t interfere with the fold up.
It needed some kind of back to keep people from falling off backwards. A simple swing arm accomplished this task. It was narrow enough so as not to interfere with the unit’s ability to pack up. This had all the rough mechanics I wanted, but was narrower and not as deep as I felt it should be. Also I wanted the step portion to be adjustable as the child grows. On to the next prototypes.
I am going to use dowel nuts and binding screws to make something that was strong, but could be removed and reassembled. It would take a number of holes drilled in the right places to make that work. I planned the sizes of the parts and printed out drill guides that would hold brass tubes to act as drill bushings. The brass won’t last forever, but is easy to cut and insert, and helps keep the hand drilling accurate.
First up I clamped the jig in place and used a transfer punch to mark the centers of where the barrel nuts will go. This makes drilling on the drill press easy.
Next to accommodate the bolts, I need to drill a long hole end-on to meetup with the cross holes. This can’t vary much and the parts are too long to use the drill press, thus the drill jig idea.
With both sets of holes accurately drilled, the nuts and bolts will meet up in the correct spots.
With the folding and adjusting mechanics worked out I could move on to the real thing. I selected 1×3 pine for the uprights and spreaders. The step spreader got its holes drilled with the above jigs, and the other two spreaders received a set of fair curves thanks to my new drawing bows.
Part of the assembly folding out and being stable is having the sides only fold out 90 degrees. They must positively stop when they reach the right angle. I do this by firmly clamping the sides and uprights together and routing a small pocket for the hinges. This 3d print has a center-line mark on it and is perfectly spaced to make a tight mortise for the hinges. The result is a flush hinge and sides that do not swing out past where you need them.
I assembled the step and determined how high it could go when folded up. Too high and the step hits the top spreader. Marking those places I could make a row of holes that would allow the step assembly to adjust as needed. The sides and uprights got a set of holes placed every 2 inches.
To lighten the structure and add something fun, I printed a series of shape templates. Double sticky tape holds them down, and a plunge router cuts them out quickly. I made 8 unique shapes and it really adds a lot.
I put the center spreader in at the top most position and marked where the stops should be. Each one has two t-nuts hammered in place. Bolts go in from the outside to hold those securely. Now to adjust the height you have 8 bolts to remove. 4 from the stops, and 4 from the folding step. The final unit is light, compact when folded, looks decent (even though most of it is plywood), and should have enough room for any kid small enough to need it. The swinging back stop is made with another set of dowel nuts and binding screws. Everything got a coat of shellac as basic protection.
As a final bonus, I was able to cut the shapes out carefully enough that they all survived in tact. I rounded the edges and shellacked them as well.
I want to be able to re-create this again in the future. Here is a rough parts list with sizes. Dowel nuts and binding screws are both 1/4-20s.