Bolton No.2 Mill Engine

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Beautiful ! I just recently finished 4 very similar valves for a Tiny power
Twin. 4 required $35 each without shipping. Well that is motivation.
Yes it equated to about <5$ an hour for labor. I used steel for the
male portion. I didn't bother with the square portion, does it really matter. ? I feel your joy and appreciate your work. Thanks.
I think you could probably get by with some loctite on the retaining nut. The keyed shaft is much nicer though and it works really well. The more of these I make the quicker and better they get. I've done about 5 now. I get a kick out of wasting days of my life to save a few dollars. I'm fond of making washers too!
 
The time has come to paint the engine. I thought about this quite a lot and decided to try Japanning. Japanning is what used to be used on old tools such as hand planes. It is a very hard very black paint made from something called Asphaltum which is a dark brown powder.

To make asphaltum paint you mix it with 1/3 turpentine and 1/3 boiled linseed oil. Then after giving it some time to disolve and mix together it is painted on with a normal paintbrush.
IMG_1342.jpg


Once everything is painted it is then baked in a convenient oven. I have an old toaster oven which I found in a skip which I use for this kind of thing. It's important to do it outside as it SMELLS pretty much like a road resurfacing machine.

IMG_1345.jpg


It's important to bake it slowly. I started at about 120C and gradually ramped it up a few hours at a time to about 240C or so.
Initial results were pretty awful but after another coat and more baking it turned out quite nice I think. The finish is very much like a baked enamel. Very hard and durable and very very black!

IMG_1350.jpg


I thought some pin striping might look nice so I had a go at that using a fine white paint pen from the local stationary shop.
It's not too bad I think.

IMG_1351.jpg
 
I thought this engine needed some oil cups to keep the bearings and slides nice and oily.
I started out by making a little form tool from HSS and proceeded to form little cups.
I held them in a collet to drill the hole in the top. This was a bit tricky and as always I had to make sure I had a nicely brassed off drill bit to ensure no grabbing.

IMG_1354.jpg


I put a 2.5mm thread on the end and drilled a 1mm hole
IMG_1355.jpg


Maybe they are a bit out of scale, I'm not sure. On the whole I think they look ok.
IMG_1356.jpg



I'm not a fan of lids as they tend to get lost instantly. They seem to work ok.
IMG_1360.jpg
 
I hadn't seen this thread before, but I went back and read the lot. Nice work on a great engine! It's looking fantastic.
It's amazing how many good workholding (and other) tips you can pick up on this forum.
 
This looks absolutely awesome. I am very jealous of your machining skills.

With the world on a slow-down at the moment, I may crack out my Stuart S50 kit that I have in the bottom of my lathe cabinet. Although, it won't look as good as yours.

Great work. Do you have a nice video of it running available anywhere?

Best Regards,

Del
 
This looks absolutely awesome. I am very jealous of your machining skills.

With the world on a slow-down at the moment, I may crack out my Stuart S50 kit that I have in the bottom of my lathe cabinet. Although, it won't look as good as yours.

Great work. Do you have a nice video of it running available anywhere?

Best Regards,

Del
Hi Del,
Thankyou for your nice comments!
I don't have a video of it yet. I want to add a couple of more bits of bling and then I will make a nice video.
I'm currently just about finished making a displacement lubricator and then I want to make a nice steam valve for it.

Definitely have a go at your S50. Too many engines sit forever in drawers waiting to be built.
You can always get spares if you make a mistake so why not give it a go!
 
Thank you for all your effort in taking and posting photos and text! I've really enjoyed seeing your work. Nice explanation of setups, and an even bigger thanks for not hiding the bits that are tricky (crosshead). So often you KNOW something was tricky, knowing that that's the case lets you relax and plan on doing something else if not fresh and energetic :)
 
I hadn't seen this thread before, but I went back and read the lot. Nice work on a great engine! It's looking fantastic.
It's amazing how many good workholding (and other) tips you can pick up on this forum.
I agree. I found this thread today and read the lot. Picked up quite few work holding tips. Great job.
 
I've somehow missed this build also. Great work, I look forward to seeing it running.
 
Encouraged by all your recent comments here is the latest instalment in my Mill Engine build ...

I've never built a displacement lubricator before so I thought I would try to make one for this engine. I had a look around for ideas and found some basic plans on the internet to work from.

Fortunately I had recently purchased a set of micro drills and this was a good chance to try them out. They worked very well and I managed to put six tiny 0.5 mm holes in the end of my little drain valve with no problems.
IMG_1593.jpg



I knurled a piece of brass and soldered it to the shaft after cleaning it up into a tiny disc.
This photo also shows the bottom of the lubricator which I machined with a nice curved form tool.

IMG_1594.jpg



I always enjoy making knobs and the top adjustment knob was probably the smallest one I have made so far.
I dished it out with a ball nose end mill and used a form tool to radius the edge. I then scalloped the sides using the side of an end mill and a hex collet block. This photo shows me cleaning up the threaded section trimming it neatly to fit the little 7ba nut that retains it.

IMG_1603.jpg


Here are all the parts ready to assemble. I don't think I quite got the o-ring right but it should work ok regardless.

CAE16D25-634C-441B-B20D-67B3F5E5AAAD.jpg



And here is the finished lubricator mounted on the engine. It might be a while before I can determine if it works but I think it should be ok.
IMG_1604.jpg
 
Very nice and detailed building report.
I just have a problem understanding the function of this drain valve at the bottom of the oiler - I always have a simple screw there with no holes in it. Please details.
 
Very nice and detailed building report.
I just have a problem understanding the function of this drain valve at the bottom of the oiler - I always have a simple screw there with no holes in it. Please details.

The idea of the holes is so that you can loosen the screw and the liquid will flow out through the bottom of the plug. You don't have to completely remove it to let the liquid out.
 
I understand, the cone on the screw has a seat in the body above! And the six small bores are only connected to the central outlet below.
GENIAL!
I always had dirty fingers....
 
Encouraged by all your recent comments here is the latest instalment in my Mill Engine build ...

I've never built a displacement lubricator before so I thought I would try to make one for this engine. I had a look around for ideas and found some basic plans on the internet to work from.

Fortunately I had recently purchased a set of micro drills and this was a good chance to try them out. They worked very well and I managed to put six tiny 0.5 mm holes in the end of my little drain valve with no problems.
View attachment 114611


I knurled a piece of brass and soldered it to the shaft after cleaning it up into a tiny disc.
This photo also shows the bottom of the lubricator which I machined with a nice curved form tool.

View attachment 114612


I always enjoy making knobs and the top adjustment knob was probably the smallest one I have made so far.
I dished it out with a ball nose end mill and used a form tool to radius the edge. I then scalloped the sides using the side of an end mill and a hex collet block. This photo shows me cleaning up the threaded section trimming it neatly to fit the little 7ba nut that retains it.

View attachment 114613

Here are all the parts ready to assemble. I don't think I quite got the o-ring right but it should work ok regardless.

View attachment 114614


And here is the finished lubricator mounted on the engine. It might be a while before I can determine if it works but I think it should be ok.
View attachment 114615


I've been making a displacement lubricator literally the last 2 days. (Couple of hours each day)
Been filming it in 4k too, to whack up on YouTube.

Yours is a lovely display of craftmanship.

Can you provide a few more photos of the drain valve? Am I right in thinking it is a single taper valve, with a hole 90% through the centre, then the 4 or 6 drain holes just below where the taper will seal?? Did you bother with any sealant below the threaded part??

I rushed 2 of these! Both Failed. The smaller the part, the more critical the measuring, obviously, and I made a mess of the same bit, twice.
Ended up drilling too deep on one, and the hole just went straight through the whole body.
No. 2, I didnt drill deep enough, then when I was trying to drill it again, it went too far AGAIN!!
Time to make one properly i think.

Re the taper valve seat and threaded part, did you make it in one long piece, silver soldered through the main body of the unit, then re-drill the oil reservoir once soldered, or solder the 2 parts into the main body separately? (Sorry if that didnt make much sense!)

Kindest Regards,

Del
 

Attachments

  • 20200327_134636.jpg
    20200327_134636.jpg
    156.1 KB · Views: 318
  • 20200327_134702.jpg
    20200327_134702.jpg
    192.9 KB · Views: 360
I've been making a displacement lubricator literally the last 2 days. (Couple of hours each day)
Been filming it in 4k too, to whack up on YouTube.

Yours is a lovely display of craftmanship.

Can you provide a few more photos of the drain valve? Am I right in thinking it is a single taper valve, with a hole 90% through the centre, then the 4 or 6 drain holes just below where the taper will seal?? Did you bother with any sealant below the threaded part??

I rushed 2 of these! Both Failed. The smaller the part, the more critical the measuring, obviously, and I made a mess of the same bit, twice.
Ended up drilling too deep on one, and the hole just went straight through the whole body.
No. 2, I didnt drill deep enough, then when I was trying to drill it again, it went too far AGAIN!!
Time to make one properly i think.

Re the taper valve seat and threaded part, did you make it in one long piece, silver soldered through the main body of the unit, then re-drill the oil reservoir once soldered, or solder the 2 parts into the main body separately? (Sorry if that didnt make much sense!)

Kindest Regards,

Del


Hi Del,
If you are having trouble drilling brass or bronze accurately you might want to try 'brassing off' your drill bits. This is a term that refers to flattening the front cutting face of the bit so that it does not dig in suddenly. It's a bit tricky to explain but Clickspring has a great video on the subject. Here is a link:

I am fortunate to own a rack and pinion style tailstock on my lathe. I made a small locking collar for that which acts as a depth stop. I mainly use it with gauge blocks to set very accurate and repeatable depths. This is a photo of what it looks like.
SkzGfDuTS3SxRhKluSDUvg.jpg

I made my taper valve in one piece complete with all the threads and holes. I then silver soldered it into the main body. Here is a photo of it before I soldered everything. I don't have a boiler yet so I have no idea if it will actually work. One day I will get that done. The copper for it is sitting on my bench.
xjPuioiSTFiw4zjS6Dcgug.jpg
 
Once I finished my displacement lubricator I decided that the engine also needed some kind of valve. I set about making a globe valve from scratch by using a form tool to cut the body.
IMG_1633.jpg


Once this was done I drilled it out and silver soldered in the center part which the handle connects to. Once it was silver soldered I drilled it out and then bored out a recess inside which is wider than the threaded section. That allows holes from the sides to be drilled to the top and bottom halves of the valve.
IMG_1635.jpg


I used the rotary table to put holes in the ends so I could bolt the flange to my engine using 10ba bolts.
IMG_1634.jpg



The top section was made in two parts which were then silver soldered together.
IMG_1638.jpg



Amazingly this worked and I was able to screw the top into the body of the valve. I'm not sure yet if this will be steam tight but I should be able to put some stuffing inside if it leaks.
IMG_1639.jpg



The last step was to make a little handle for it. I wanted something which wouldn't get too hot so I came up with this little ship's wheel design. I made it by milling out the gap between the hub and the outer rim and then drilling through the holes for the 8 spokes while it was still one piece of rod. Once all the spokes were fitted and soft soldered I parted the whole lot off and cleaned up the rear side. It's super cute!
IMG_1649.jpg



And here is the whole thing bolted to the engine. I am really happy with how it turned out.
0FEF2118-CFED-4A2A-A1CE-25BC544E7620.jpg
 
Nice, nice, nice, much work to get the radius?

Thanks!,
I used a radius dresser to make a round shaped grinding wheel for my surface grinder. I used that to make a very accurate concave lathe tool from HSS by holding it at 7 degrees compound angle in my sine vise. So it wasn't too bad really. Sometimes if they are large radius I just do them by hand with a belt grinder. Another good way is to use a dremmel. It's worth doing because you always have them and they are always handy.
 

Latest posts

Back
Top