8" Steel Scotch Boiler

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tel said:
The cradles it is sitting in?

Yup I am sure what ever your design...won't go anywhere Bob ;D

Just couldn't tell from the 3/4 iso view.

Dave

 
Bob,
That is looking really good. I see there is a plate on one end of the grate, as the grate is only about half the length of the furnace tube I am assuming the plate goes in the middle to act as a back stop for the coal.

You mentioned a fan for solid fuel a few posts back so I am wondering where the forced draft opening is?

Dan
 
Dan Rowe said:
Bob,
That is looking really good. I see there is a plate on one end of the grate, as the grate is only about half the length of the furnace tube I am assuming the plate goes in the middle to act as a back stop for the coal.

You mentioned a fan for solid fuel a few posts back so I am wondering where the forced draft opening is?

Dan

Hi Dan,

Thanks for stopping by. :bow:

Yes, the plate on the end of the grate is basically a poor mans brick arch.

My 1st idea is to fire it with a blowlamp type burner using kerosene/paraffin.

For solid fuel, I am torn between induced draft using a blast pipe in the base of the funnel coupled to engine exhaust and using the lower half of the air space at the front, with some holes drilled through the lower half of the furnace tube and a sliding damper with handles on the front, (similar to an Admiralty closed register).

Best Regards
Bob
 
Bob,
If you go with solid fuel and induced draft do you plan a steam blower for the engine to idle, and I think a suction fan would be needed for start up.

Some folks with locomotives have been using perforated metal for the grate. Here is a link for those on this side of the pond for perforated metal 1/4" thick with 1/4" holes.
http://www.onlinemetals.com/merchant.cfm?pid=15701&step=4&id=1004&top_cat=849

Dan
 
Dan,

You've really got the old grey matter bouncing around. My initial thought was that with the engine stopped there would be little requirement for draught but if needed a supplementary supply from the auxiliary stop could be arranged. For start up I had envisioned using compressed air. Don't ask me why but the suction fan has little appeal.

Best Regards
Bob
 
Yup induced draft blower would be a good one to have. as well as injector nozzles with nice dry steam.

Dave
 
Nice one Bob, on my watch list now.

I'd say you'll need the blower, the little gas fired Scotch I did the other year had to be started on a very low gas to get thing warmed up before it started to draw. I came to the conclusion that the folded design doesn't help this. If you are going to solid fire it I guess there would be even more need for a blower, although design is shorter and better proportioned to the real thing.

Pete
 
Dave and Pete,

It's been awhile but at the moment I'm waiting for some bits for the electrics on the Hit and Miss. So without further ado Today was the day to see if I could abuse my lathe to the point where it would machine the shell which is 8.75" OD.

Here's the result

Shell1.jpg


Shell2.jpg


Shell3.jpg


Shell4.jpg


I managed a recess on each end to locate the smoke box plates which seemed like a better idea than welding in some blocks for screws.

If anybody tries to tell you 8" boiler tube is round, take it from me............it ain't :eek:

Best Regards
Bob
 
Looking good Bob. Can we have some more detail on the + at the tailstock end please. Are there adjusting bolts fixed to the back of the cross pieces?
 
Herbiev said:
Looking good Bob. Can we have some more detail on the + at the tailstock end please. Are there adjusting bolts fixed to the back of the cross pieces?

Hi Herbie,

The gizmo is commonly called a spider. The back side has a 1/2" nut welded near the end of each piece then 1/2" bolts are screwed into the nuts. This allows for it to be adjusted and centralised. Normally it's not a big deal but in this case I needed the adjustment for when I turned it around to machine to length and cut the second recess.

Best Regards
Bob
 
Good to see some progress Bob, I will be watching as the project moves along.

My own scotch had to be put on hold for a while as with the rest of my projects,
Life has an uncanny knack of upsetting ones playtime. :(

Cheers Neil
 
Maryak said:
Hi Herbie,

The gizmo is commonly called a spider. The back side has a 1/2" nut welded near the end of each piece then 1/2" bolts are screwed into the nuts. This allows for it to be adjusted and centralised. Normally it's not a big deal but in this case I needed the adjustment for when I turned it around to machine to length and cut the second recess.

Best Regards
Bob

It's also been called a "cats head" though was semblance it has to a cat is beyond me.... ;D

Turned up some bronze plunger pump rams using a rig similar to that....they were'nt round either :big:

Dave
 
Hi Guys,

Well here we are again.

I hope you are finding your way around. OK we were all familiar with the old setup and to be honest I think it was way more intuitive than this version.

Having said that, my tip is keep your eyes peeled as there are many more drop down menu's which give similar if not quite the same outcomes as those with which you were familiar.

Now about that boiler..............some time ago I bought a 3 in 1. Well today was the plasma cutter's first outing in earnest. I had to cut the 2 end plates from a biggish lump of 3/8" plate.

I faffed about with test cuts, playing with amperage and air pressure until I managed a clean cut :eek:

The cutter performed beyond my expectations and gave a better result than my friends single purpose cutter for which he paid close to $AU1000.

Now all I have to do is weld them together, marked them off, drill, bore, shape and chamfer them.

Avagoodweekend.

Oh and did I say I received the bits for my Hit and Miss Electrics. So next week I hope it's Chitty Chitty Bang Bang. :eek:

Best Regards
Bob
 
Hi Bob.
I am still watching this build. I am thinking about a similar boiler for my Stuart Cygnet.

What is a 3 in 1 other than a plasma cutter? I have never been happy with my skill with an OA gas axe.

Dan
 
Hi Bob.
I am still watching this build. I am thinking about a similar boiler for my Stuart Cygnet.

What is a 3 in 1 other than a plasma cutter? I have never been happy with my skill with an OA gas axe.

Dan

Hi Dan,

The other 2 are TIG and MMA welding. It's a DC machine so, It will not successfully TIG weld Aluminium.

Best Regards
Bob
 
I too could not believe the power of these plasma cutters. No more ridiculous rent for oxy/ acet bottles. Just hook up to the compressor and a clean smooth cut every time far better than I could get with the oxy/acet rig. Good investment Bob.
 
Hi Guys,

Yesterday was yet another test of my lathe, as I attempted to machine the furnace tube down to manageable sizes. The tube I scrounged was around 70mm dia with a wall thickness of 10mm. I wanted it to end up around 2-5/8" with a wall around 1/8"

With some 8" hanging out of the chuck I made up a kind of pipe centre to fit my running centre and the outside was machined to size.

DSCF1602.jpg


Next came the inside. The tube is 7-3/8" long and so first up I had to remove the tailstock to get enough travel for the saddle and boring bar. My fixed steady was another problem as the provided maximum diameter was 2." More faffing about saw this modified to accept the 2-5/8" requirement.

DSCF1603.jpg
.

At this stage all I can say is, the gods must be smiling, because I fluked the size of this thing just enough that my machinery will handle it. :eek:

Best Regards
Bob
 
Machining the furnace tube.

Outside

DSCF1602.jpg


Inside

DSCF1603.jpg


Best Regards
Bob
 

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