Nice job on both pieces.
PeeWee V4 slow build
- Thread starter Cogsy
- Start date
Help Support Home Model Engine Machinist Forum:
- Joined
- Sep 19, 2015
- Messages
- 274
- Reaction score
- 80
Cogsy that look an absolute treat mate .
John
John
Cogsy
Well-Known Member
I finally had cause to try out the Alum dissolving ferrous materials trick :wall:, so for anyone interested I thought I'd post my results.
For starters, I can't find anywhere in Australia that actually stocks Alum, and I've always meant to import some to have on hand, but haven't gotten around to it yet. However, the kids have a couple of Chemistry and Crystal Growing kits and I managed to find the stuff in both of these kits under it's chemical name (which I can't remember off the top of my head), so I stole theirs and promised to replace it later.
The saga (as it turned out to be) started with breaking off a very small drill bit in quite a deep hole, in a part I thought I had too much time in to start again. Actually, the part wasn't that difficult to make but I wanted to recover the base material that did take me a lot of time and effort to get. So I made up a solution of Alum and water, saturated at boiling point, and dropped the part in. In the picture, the hole closest to camera has the bit in it.
Once I had the mixture simmering away, the reaction started and I eagerly awaited the result. In this next picture, the 'milky' stuff coming from the hole is actually a stream of very small bubbles coming out of the hole with the drill bit in it.
Even though the reaction seemed quite vigorous, it took a really long time to get anywhere. Obviously the end of the drill bit was quite a small area and I imagine the flutes were full of chips and the Alum couldn't get down to the full length, so it was slowly eroded from one end only. I had to keep topping up the water and scraping the gunk from the bit out of the hole. In the end this took a solid week on the stovetop for a few hours every night, and made quite a mess of the stovetop and surrounds. Eventually though, it removed all the drill bit and left the brass/bronze? work piece almost unaffected. It changed its appearance to a copper tone but this was just a surface effect and easily removed. In the end, I should have just started again as it was more trouble than it was worth, however I would use it again for either a very complex or expensive part. I would expect it to work better with a tap or bit that wasn't fully choked with chips and allowed for more contact with the Alum and let it work faster. This pic shows the piece straight out of the Alum and the pretty colour it became.
And finally, here is the intake manifold I whipped up one day while I waited for the Alum to work.
For starters, I can't find anywhere in Australia that actually stocks Alum, and I've always meant to import some to have on hand, but haven't gotten around to it yet. However, the kids have a couple of Chemistry and Crystal Growing kits and I managed to find the stuff in both of these kits under it's chemical name (which I can't remember off the top of my head), so I stole theirs and promised to replace it later.
The saga (as it turned out to be) started with breaking off a very small drill bit in quite a deep hole, in a part I thought I had too much time in to start again. Actually, the part wasn't that difficult to make but I wanted to recover the base material that did take me a lot of time and effort to get. So I made up a solution of Alum and water, saturated at boiling point, and dropped the part in. In the picture, the hole closest to camera has the bit in it.
Once I had the mixture simmering away, the reaction started and I eagerly awaited the result. In this next picture, the 'milky' stuff coming from the hole is actually a stream of very small bubbles coming out of the hole with the drill bit in it.
Even though the reaction seemed quite vigorous, it took a really long time to get anywhere. Obviously the end of the drill bit was quite a small area and I imagine the flutes were full of chips and the Alum couldn't get down to the full length, so it was slowly eroded from one end only. I had to keep topping up the water and scraping the gunk from the bit out of the hole. In the end this took a solid week on the stovetop for a few hours every night, and made quite a mess of the stovetop and surrounds. Eventually though, it removed all the drill bit and left the brass/bronze? work piece almost unaffected. It changed its appearance to a copper tone but this was just a surface effect and easily removed. In the end, I should have just started again as it was more trouble than it was worth, however I would use it again for either a very complex or expensive part. I would expect it to work better with a tap or bit that wasn't fully choked with chips and allowed for more contact with the Alum and let it work faster. This pic shows the piece straight out of the Alum and the pretty colour it became.
And finally, here is the intake manifold I whipped up one day while I waited for the Alum to work.
Nice work Cogsy, won't be long before you have it running
Cogsy
Well-Known Member
The actual parts I was attempting to make when I broke the drill off in the hole are the exhaust flanges. I started with hacking out a chunk from this old firehose fitting. I assumed it was brass by the look of it, but I have others that are definitely bronze (one of which became the outer ring of my Rupnow Vertical flywheel LINK). This one was absolutely terrible to machine, with blue curly chips coming off at times it and it seemed really 'hard', so I'm not sure what it is. You can see from the picture I've had several attempts to cut pieces out of it before (with a hacksaw) and gave up. This time, I used a slitting saw and got it done, but it took a while. Roughing it into a rectangle took far longer than I thought it would too, as it was so tough to machine I was restricted to light cuts. I'm wondering if it's possibly aluminium bronze or similar, which I've heard bad things about.
Once I had it rectangular it was in to the lathe and the end profile was cut, along with the first circular whatever-it's-called. I also drilled the full depth I needed at this point. As it turned out, I didn't need any of this outside profile at all but I didn't realise this at the time.
Drilling the mounting holes resulted in the whole Alum saga detailed in my last post. Once that was over, the outer angle cuts were milled in. The drill bit and circular protrusion set the required angle nicely.
Back into the lathe, I hand filed the radii required - not under power, just for ease of work holding. Then after a bit of sanding, I parted off the first completed flange. From there, I turned another circular protrusion and parted off, rinse and repeat until I had enough to satisfy me.
With the new flanges bolted to the head I could bend up some brass tubing into a somewhat exhaust-looking shape.
Once I had it rectangular it was in to the lathe and the end profile was cut, along with the first circular whatever-it's-called. I also drilled the full depth I needed at this point. As it turned out, I didn't need any of this outside profile at all but I didn't realise this at the time.
Drilling the mounting holes resulted in the whole Alum saga detailed in my last post. Once that was over, the outer angle cuts were milled in. The drill bit and circular protrusion set the required angle nicely.
Back into the lathe, I hand filed the radii required - not under power, just for ease of work holding. Then after a bit of sanding, I parted off the first completed flange. From there, I turned another circular protrusion and parted off, rinse and repeat until I had enough to satisfy me.
With the new flanges bolted to the head I could bend up some brass tubing into a somewhat exhaust-looking shape.
Cogsy
Well-Known Member
Thanks Michael. I'm hoping it will be this year, but then I was hoping that last year too. I'm about to enter one of my busiest times of the year so likely going to be taking a couple of month break soon.
Congratulation Cogsy Good work!
I'm following your building with close interest because the PeeWee will be my next project.
It is very interesting what you did to remove the broken drill bit. I did not have a clue that it could be done 'very clever"
It seem that the PeeWee is almost finished.
Edi
I'm following your building with close interest because the PeeWee will be my next project.
It is very interesting what you did to remove the broken drill bit. I did not have a clue that it could be done 'very clever"
It seem that the PeeWee is almost finished.
Edi
- Joined
- Sep 19, 2015
- Messages
- 274
- Reaction score
- 80
Hi Cogsy.
Those flanges came out well . What did you use for the tube bending as they look very neat which is something I would like to learn down the track.
Cheers
John
Those flanges came out well . What did you use for the tube bending as they look very neat which is something I would like to learn down the track.
Cheers
John
Cogsy
Well-Known Member
Thanks Edi - still a long way to go. I often rush the end of a build as I get close because I get impatient to hear it run. With the Peewee I'm going to do my best to finish it off properly. I think in theory I could have it running with only a couple of weeks dedicated work but it's likely to be far longer than that.
Thanks Johno - I bought one of those small benders off eBay, and also a set of spring benders but wasn't happy with either of them. In the end I imported some low melting temp alloy (Cerrobend), annealed the brass and coated the inside with olive oil, then filled with Cerrobend. Then I turned an aluminium disc of the radius I needed and used a ball nosed end mill to groove the OD. Then cut a matching groove in a rectangular block of ali and made a rough pivot point and handle. Clamped this hodge-podge in the vice and produced the bends you see here without too much trouble, then gently heated the tubes (after cutting to length) to melt out the cerrobend. There are a couple of marks on the tubes though, so it wasn't perfect, but for only about an hours work to make the 'bender' it was a decent result. I do intend to have a go at a better bender at some point, and maybe make a different set of exhausts. My next post (maybe today?) will show what I came up with for this set.
Thanks Johno - I bought one of those small benders off eBay, and also a set of spring benders but wasn't happy with either of them. In the end I imported some low melting temp alloy (Cerrobend), annealed the brass and coated the inside with olive oil, then filled with Cerrobend. Then I turned an aluminium disc of the radius I needed and used a ball nosed end mill to groove the OD. Then cut a matching groove in a rectangular block of ali and made a rough pivot point and handle. Clamped this hodge-podge in the vice and produced the bends you see here without too much trouble, then gently heated the tubes (after cutting to length) to melt out the cerrobend. There are a couple of marks on the tubes though, so it wasn't perfect, but for only about an hours work to make the 'bender' it was a decent result. I do intend to have a go at a better bender at some point, and maybe make a different set of exhausts. My next post (maybe today?) will show what I came up with for this set.
Cogsy
Well-Known Member
This will likely be the last update for a while as life things get very hectic for me at this time of year, but at least I got the exhausts finished to a reasonable standard.
Following on from the last post, I had the basic pipes bent up and now I needed a way to join them. I chucked up a piece of mild steel and machined a thin walled collector with ID slightly less than the two pipes.
Next I machined 2 pieces of solid the same diameter as the pipes but with a slight taper on the ends, to use as 'formers' I guess you could call them. Using a bit of gentle persuasion (with a small hammer, that's why it was gentle) I got them both to fit, then tried to bend the sides of the collector in a little.
From there, into the vice to close them up and the basic shape was done. Parting off from the parent stock and milling of the flange end completed them.
Next I drilled and tapped a piece of steel bar as a fixture to hold the whole setup for soldering. I used liquid paper (white out) to stop the pipes soldering to the fixture and it worked well.
A few hours in a citric acid pickle and a quick scrub with some 600 grit paper and most of the solder scale was removed, but I still didn't like the look.
So I decided to try nickel plating them, and although they looked pretty good coming out of the nickel, in a few spots the coating wasn't all that thick. Instead of recoating in the nickel I went for chrome plating instead. In the pic below, the bottom yellowish coloured one is nickel plated, while the top one is chromed and, I think, looks a lot nicer in comparison. I have to say though, without the chrome to compare it to, I couldn't tell the nickel had that yellow tinge to it at all - it just looked shiny.
So that's where I've left it for now. Hopefully I'll be back at it in 8 weeks or so. Thanks for looking!
Following on from the last post, I had the basic pipes bent up and now I needed a way to join them. I chucked up a piece of mild steel and machined a thin walled collector with ID slightly less than the two pipes.
Next I machined 2 pieces of solid the same diameter as the pipes but with a slight taper on the ends, to use as 'formers' I guess you could call them. Using a bit of gentle persuasion (with a small hammer, that's why it was gentle) I got them both to fit, then tried to bend the sides of the collector in a little.
From there, into the vice to close them up and the basic shape was done. Parting off from the parent stock and milling of the flange end completed them.
Next I drilled and tapped a piece of steel bar as a fixture to hold the whole setup for soldering. I used liquid paper (white out) to stop the pipes soldering to the fixture and it worked well.
A few hours in a citric acid pickle and a quick scrub with some 600 grit paper and most of the solder scale was removed, but I still didn't like the look.
So I decided to try nickel plating them, and although they looked pretty good coming out of the nickel, in a few spots the coating wasn't all that thick. Instead of recoating in the nickel I went for chrome plating instead. In the pic below, the bottom yellowish coloured one is nickel plated, while the top one is chromed and, I think, looks a lot nicer in comparison. I have to say though, without the chrome to compare it to, I couldn't tell the nickel had that yellow tinge to it at all - it just looked shiny.
So that's where I've left it for now. Hopefully I'll be back at it in 8 weeks or so. Thanks for looking!
Alum common as up in Thailand.
We use it in the large fish bowls that have clay as a base for the water lily.
Alum settles any clay cloudyness in the water in a matter of 1/2 hour or so.
Get it in rock form just about anywhere up there.
We use it in the large fish bowls that have clay as a base for the water lily.
Alum settles any clay cloudyness in the water in a matter of 1/2 hour or so.
Get it in rock form just about anywhere up there.
Hi Cogsy!
How is your PeeWee building? Did you finished it?
Long time since your last post.
Edi
How is your PeeWee building? Did you finished it?
Long time since your last post.
Edi
Cogsy
Well-Known Member
Hi Edi, No, not finished yet, life got in the way again. I have just started to get back into it though, and surprisingly there isn't that much left to do, so I'm hoping it will run this year. The speed you're going yours will probably be finished first though!
Yes you use a split bearing
Thanks Michael-au !
Cogsy
Well-Known Member
Mine didn't turn out as nice as Michael's but you can see how I made them in post 172 - Link. The thin walls that form the thrust washer portion of the bearing made it difficult to construct them, but I stole Michael's idea of using a dummy conrod during machining of the big end bearings and it was much easier. Next time I make a center bearing I'll make up a similar clamping fixture and it will be far simpler.
.625 x .625 inch
I have a question: it's too small, so how much compression ratio ??
Thanks.
