The Post Man Cometh.

[Nick_GParticipant @nick_g]

James Coombes Engine

[Nick_GParticipant @nick_g]

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With a box of bits :-

So in the famous words of Captain Lawrence Oats. " I may be gone some time."

Nick

[Boiler BriParticipant @boilerbri]

Nice have fun. My c106 copper also came today, so I can now get with my boiler.

Not looking forwards to my credit card bill though😪

Bri

[GaryMParticipant @garym]

Good luck with the build Nick. One thing I found with the S50 kit was that some of the stock supplied is only just slightly larger than the part to be made, a bit mean considering the cost of the kits. I found it useful to have some spare stock in the appropriate sizes to give a bit more room for manoeuvre and also if I made a mistake I could have another go immediately without waiting a few days for metal to arrive.

Gary

[Nick_GParticipant @nick_g]

Posted by GaryM on 28/10/2014 21:58:56:

some of the stock supplied is only just slightly larger than the part to be made,

Gary

I have just noticed this.!

On the James Coombes there are 2 plates. The supplied stock is slightly smaller than the specified size on the drawing before I even start to square them up.

These are not critical parts so long as they are both the same. But that is not the point now is it.??? – The parts and their placement that go onto these plates however are critical.

Anyway. I have squared them up and this gave me a good excuse to have a play with the new mill and its associated sundries I have purchased.

Bad news is I have come to the conclusion I need to buy a height guage.

Nick

[Ed DuffnerParticipant @edduffner79357]

Is it finished yet?

Would a scribing block give you the accuracy Nick?

[Nick_GParticipant @nick_g]

Posted by Ed Duffner on 29/10/2014 01:27:19:

Is it finished yet?

Yeahhh, course.! ……………. I am just waiting for the paint to dry and the compressor tank to charge.

Nick

[Nick_GParticipant @nick_g]

.

Painted over a few castings yesterday with a preliminary coat of red oxide and this evening I sized up the pedistal / base.

Nick

[Nick_GParticipant @nick_g]

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It's getting taller.!

I will trim the studs that go through the top plate to make them all the same length.

Also on examination there is a casting that provides a pedistal for one of the main bearings. This is a bit banana shaped. So I rang Stuart's today and they are putting a replacement in the post.

Nick

[Boiler BriParticipant @boilerbri]

 

Wow, you don't waste time, looking good keep the pics coming.

It looks like your getting to grips with the new milling machine. 

Bri

Edited By Boiler Bri on 31/10/2014 19:23:38

[JasonBModerator @jasonb]

That's comming on well, don't polish those columns up too much, the paint won't stick

[Nick_GParticipant @nick_g]

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When it comes to boring the cylinder, which is a 1" diameter. I have a 1" machine reamer.

Is it OK to make the final pass on the bore with this reamer or is there a reason why this is not a good idea.?

Nick

[JasonBModerator @jasonb]

Assuming it came with iron rings I would bore and hone it but you could also bore, ream and hone which would eliminate any possible taper caused by a bit of spring in the boring bar.

Before you start machining the cylinder poke a bit of wire through t eports to make sure they are clear and remove any remaining sand from the cores.

J

[Nick_GParticipant @nick_g]

Posted by Nick_G on 31/10/2014 19:08:46:

.

Also on examination there is a casting that provides a pedistal for one of the main bearings. This is a bit banana shaped. So I rang Stuart's today and they are putting a replacement in the post.

Nick

.

It gives me pleasure to report that less than 24 hours later from the phone call a replacement casting has arrived from Stuart. (a straight one. )

Nick

[Boiler BriParticipant @boilerbri]

Interesting point on the honing, I had a small stainless steel 30ml volumetric pump sent back this week from a well know whiskey maker/bottler. When I manufactured it I had the bore mirror finish for the piston, PTFE to run against. Over time the PTFE was rubbing off in the form of a black paste. It had started to show in the bottled whiskey.

The cure was to finish the bore to: 16-32 micro inches which looks like it had been sanded not honed. The PTFE will over the first 30 minutes of the pump running shed and fill the pores of the metal with PTFE , this will then rub against the piston, also PTFE and solve the problem.

After a lot of years in the bottling trade I have learnt something new!

Bri

[Neil WyattModerator @neilwyatt]

If they need a volunteer to dispose of the contaminated whisky, I'm sure I can help.

Neil

<starts searching out filter papers>

[Nick_GParticipant @nick_g]

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Hi folks, back on parade with a little bit more construction. I did intend to spend the entire of last Sunday in the workshop but due to my own stupidity Sunday was a total write off due to the mother of all hangovers and I spent it lay on the sofa feeling sorry for myself while cursing myself.

Anyway, the cylinder has been attacked.

The port face had been milled prior to the boring and facing operations.

 

The flywheel has also had some disciplinary corrective treatment issued. The first side was faced and turned. Also at this setting the bore was drilled and reamed. (not shown)

 

 

Video can be seen here :- **LINK**

 

The flywheel was then flipped over and centered so the other side could be faced.

 

Nick

Edited By Nick_G on 05/11/2014 21:47:39

[Boiler BriParticipant @boilerbri]

Hi Nick. All looking good. Just a bit worried about those clamps. I thought you had to have a packing under the lower edge to make them clamp properly?

Bri

[Boiler BriParticipant @boilerbri]

Just watched the vid. What's the coloured packings ?

Bri

[Nick_GParticipant @nick_g]

Posted by Boiler Bri on 05/11/2014 22:03:12:

Hi Nick. All looking good. Just a bit worried about those clamps. I thought you had to have a packing under the lower edge to make them clamp properly?

Bri

Do I.? ………….. Ooops.

It does seem however that I 'got away with it' ………… This time.!

Thanks for the info. I shall know better next time.

Nick

[JasonBModerator @jasonb]

Looks like the clamps actually wedged themselves between two spokes rather than just the cranked end holding things down. Also make sure the bolt is near the work end not the support end like you have them.

Oh and hold your phone the other way round when doing a video, thought a photographer whould know that

Comming on wel though

[Jerry WrayParticipant @jerrywray14030]

While thinking about whiskey (whisky?)my mind went back over my own experience to recall when I was heavily involved in lining of steel drums. Our lab, probably the most expert in Europe discovered that resistance to gin and whiskey was the most difficult to achieve, more so than almost all other chemicals.

It's not the finish that's important but the characteristics of the polymer.

Jerry

[Ian S CParticipant @iansc]

Nick, on the flywheel casting there should be packing under the spokes, so that the clamp presses down on the spoke and the packing against the face plate. To get adequate clamping without the intervening packing risks breaking the spoke, or if like most of my flywheels the spokes will bend as they are made of hot rolled plate.

Ian S C

[Nick_GParticipant @nick_g]

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Bit of help please guy's.

Whats the best machining process / order to turn this rascal :-

Into this :-

I presume the spigot in the bottom of the casting is to assist in holding during the process.

Many thanks, Nick

[Paul LousickParticipant @paullousick59116]

Nick,

I would center it in the lathe chuck, face the back and turn the boss first which will give you a datum face and location diameter to machine the opposite sides and remove the location spiggot.

The drawing does not show any surface finish or tolerance for dimensions. Check it they are required before you start machining.

Paul.

Edited By Paul Lousick on 14/11/2014 22:43:55

Edited By Paul Lousick on 14/11/2014 22:47:25

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