Park bench: mount

Today I worked on the base mount for that bench. I chose a 20 degree slope (taken from that guide) as I found it comfortably and it’s a round number too.

I fumbled a bit with some pipes but the cuts and copes to build it properly are more demanding than the time I had, so I settled on some channel iron. The math is a lot easier, I just needed to offset one cut by (channel width) * tan(20°) or 2.6 cm.

I’m very pleased with how I managed to make this weld around the corner in one pass:

Park bench: corner weld

DTMF Remote control and sequencer

Many years ago I built a remote control for our transmitter. It was pretty simple, just a dtmf decoder rescued from an old answering machine.

It served us well for a long time, however it was lost when we moved to a new location.

For the last couple of weeks I spent a while polishing the firmware and making new boards in KiCad. The original was very crude, just a simple on/off panel and delayed power sequence.

This one adds an RF sense and automatic restart, so if one of our amplifiers bails out on a power dropout we don’t have to do anything about it.

Yesterday I etched the boards. I ran out of toner and had to ask a friend to print the transfers. They came horrible but work fine nevertheless.

It’s amazing that nowadays buying an arduino and a preassembled dtmf decoder is cheaper than the single chips (and not counting the time to layout a more complex board).

All the design files are here: https://github.com/fm-futura/dtmf-remote-sequencer

DTMF remote

C Clamp

Just a small Sunday project.

Here at the Uni lab we have a nice articulated lamp that lacks a base. It’s been sitting on a corner for ages so I set to make a new clamp for it.

The frame is just a bit of T beam with a nut and some square tubes welded.

For the handle I used a bit of 3/8 threaded rod and a big washer I had lying around. In order to fix it I decided to make a hole along the axis and tap it to M3. After center punching the rod I screwed it to the drill press, using a center drill to align it. The plan was foiled when I tried to drill, as I left the base loose and it moved. But it’s good enough.

My initial idea was to use another nut and a locking pin behind the front washer but that used up a loot of the available space inside the clamp. After a bit of head scratching I ground a small taper and added a small washer to push the bigger one instead of a nut. I’m quite proud of how it turned out.

Homemade C clamp
Homemade C clamp

Park bench

A while ago we were given a bunch of weathered wood from a deck. Some of us have been thinking of installing seats on the sidewalk and this looked like a good opportunity.

I looked around Core77 and there’s an entry just about seating that produced this helpful guide:

I built a simple frame with square tubing and used one of the wood packs to try it out. I need to select the best planks but it’s comfy and with a bit of paint will look good.

Assorted clamps

The last two days I finished the welds on those clamps,  built some to hold the other end of the ropes and four sturdier to screw to the roof trusses. All the screws are paired with either a nylock or two nuts locked to each other.

I painted the pieces for the bottom frame with black enamel and the ones for the roof with white to match the rest of the room. I know they’ll rust in some weeks but I left the blued surface exposed. I never tire of looking at them.

Side table iron legs

We had a nice wood slab from the kitchen remodelation and wanted to make a small table with it.

I did a quick sketch and started to build the base. I goofed a bit when cutting the intersections but it ended up fine and level on the first time anyways.

Sometimes I flunk on the easiest of the welds and others, I make a perfect one in a very hard spot. I did this one on a single pass with a bent rod and even had slag peel:

Ceiling lamp fixture: now on steel

For the last couple of weeks I worked on building a steel version of that fixture in order to hang some cable trays and a couple of other things.

After a bit of measuring I prepared all the cuts. For the sides that aren’t at a square angle I left a bit of extra material to fold over the corner. The clamps for the trays will be made with cutouts from square tubing to have a consistent size and some flat stock. I spent quite a bit of time on this phase but I’m pleased with the outcome.

For this welds I tried as much as possible to either manipulate the rod with my left hand only and sometimes with the right, but I still need a lot of practice with that. Some were awful, but others like this one are quite passable:

Lamp fixture: corner bracket, weld detail

A quick test fit and everything fell into the right place. I love it when a plan comes together.

Lamp fixture: trial fitting

Grandpa’s 504: The beginnings

During the last week I began to clean and dismantle the engine of that Peugeot 504 using whatever spare time I had.

I started by removing the battery plate, water and vacuum reservoirs and the hoses connecting them. I took a couple of detailed pictures so I don’t forget how to put it back together later.

I spent a while trying to figure out how to remove the radiator, it’s bolted to the car frame and there’s a plastic cover around the fan blades that doesn’t let it move up. The most obvious way seemed to remove the front grill and the body panel behind it but in order to do that I would have to tear apart the original glue and make a couple of cuts. I kept looking and feeling around until I discovered that the air guide is only held by two nuts on the top and locking pins on the bottom.

After removing them, it glided freely upwards and then to the back. With nothing else holding it, the radiator also came out.

That freed up some space in the engine bay. I moved on to the belts. This is a very good time to take note of how everything is installed.

Then I moved onto the hoses. Some were hard and brittle and others felt like new. But all were filled with rusty mud.

The water pump was no better, the impeller stayed inside the block.

The radiator has a lovely copper corrosion growth. After draining it I poured hot water on one side and let it flow, touching along the fins to see if there were clogs. Except for a small hand sized area on the bottom everything seemed fine.

Grandpa’s 504: hydraulics

This happened in between the last installment in the series.

Both the brakes and clutch didn’t work (besides not having fluid, the cylinders were stuck) so I set up to dismantle them.

After some contortions I managed to free the mechanism. A couple of hard lines broke around the fittings and part of the servo assist snapped while I was pulling.

The air filter in this unit is an oil bath one and was perfectly full. After draining it I used lots of gasoline, kitchen cleaner and boiling water to remove every trace of grim and oil. But now the filth migrated to the sink.

I also removed the valve cover to take a peek inside. It looks surprisingly clean and neat for a car of this age. The gasket was torn apart, that may explain the amount of oil on the block.

Peugeot 504: valve train

First run in 20 years.

Today I bought a used battery and decided to crank this old Peugeot 504 to see if the engine was seized or other problems lurked.

It’s been sitting there since 1998 but the diesel in the tank did not smell funny so I used the little pump on the filter until it became hard. On the last strokes I heard a subtle noise and there was a tiny leak on the line.

When connecting the battery there was a small spark and the position lights turned on. I let the glow plugs do their job and tried to crank.

Nothing, just a small click of a relay inside the dash. After a couple of times it turned with some effort but refused to start.

I let the battery rest for a moment and tried again. This time it roared as I pressed the accelerator, puffed some smoke and then idled calmly. I can hardly believe it awoke from a two decade slumber just like that.

Now I have to fix the water circuit (the hoses are dry and crumbling) and the clutch so I can move it around with a bit of ease.

Pouring a concrete floor

That shed I was cleaning needed one thing really bad, a decent floor. It was already made of concrete but with the years it broke down, revealing the soil and gravel underneath. And also wasn’t level.

So for the last couple of weeks we (my dad and I) worked together and made a new one. The next step is adding some tiles on top of that.