Allchin Construction

[Deleted]

Reading the Allchin construction manual I cannot find Ref. as to
what stage the hornplates are rivetted to the stays in the boiler.
Having never built a traction engine before I am preparing a build
schedule and sequence of operations. Have I missed this info or
is it obvious.
Can anyone set me straight.
Many thanks
Peter Woodley

[jasonb]

I would leave it for as long as possible, Infact making fitted bolts would not be a bad idea, thats what I have done with my 2" Fowler, at least that way you can always get the engine to bits if needed.

Jason

[Deleted]

Dear Jason
Thanks for your reply. Good idea making fitted bolts. At least you can get the engine to bits.
Are you suggesting not rivetting at all. Sorry if this is a stupid question but I have not built a TE before.

[jasonb]

Thats it no rivits. I think the Alchin and the Fowler (MJ Eng) are the only models that have them rivited on all the others are bolted or have studs into the stays with nuts on the outside.

On my Fowler I can undo the 18 (9 each side) bolts and the whole hornplate/gear train and tender will come off. Makes it easier to work on the engine during construction and when its done if you ever had to work on the boiler its a lot easier than drilling out rivits.

This is quite a good build diary of a 3" Alchin mostly without castings that you may find useful, if your French is not much good use an online translator or just enjoy the pictures

Jason

[Deleted]

Jason.
Thanks. Makes sense, studs into the stays and nuts on the outside. Thanks again Jason

Peter

[2tenths]

Sept 2, 2010 17:34:41 GMT @woodleys said:

Dear Jason
Thanks for your reply. Good idea making fitted bolts. At least you can get the engine to bits.
Are you suggesting not rivetting at all. Sorry if this is a stupid question but I have not built a TE before.

Hi

To add to Jason's comments (I don't want to teach granny suck eggs) suggest you have axle boxes and shaft bearings mounted on the horns so that you can put shafts through them to get the correct alignment to mark off your stay holes.

I suppose that I was lucky in drilling the boiler stay holes and the horn plates by co-ordinate drilling and having a big enough milling machine to mount the boiler on and skim the stay heads to width. Even then the boiler came out 2 thou under size ;D

Regards

Tony

[jasonb]

Looks like I forgot the link to that french guys site

mbc-usinages.e-monsite.com/

And as Tony says build your horns up separately, I used 4 bits of rod machined to teh boiler width to set mine up and plain bar to to set the bearings etc, as you can see here

Jason

[weldsol]

On my Allchin & Burrell I made up bolts in stainless with rounded heads to look like rivets and nuts on the inside.
If you use studs into the stays with nuts on the outside you will have to split everything to remove ( to clear stud length) if you use bolts then you can do a straight lift / pull to remove the boiler.

Paul

[klendo]

Probably not uber friendly, but being a bit more of a purist, my father and I never used the bolting arrangment on the last traction engine we built. A traction engines original design was that the hornplates themselves actually for the sides of the firebox.
Whilst having to sucombe to current boiler rules and so forth, what we did was to ( steel boiler ) weld the hornplates to the boiler and use dummy stay heads, this way its looks as it should rather than in my opinion an un gainly protruding set of bolts etc which shouldnt be there.

Its actually quite easy to allign the hornplates themselves, personally speaking we used the old method of using string, as this was good enough, bearing in mind that the main crank bearings have adjustment in 2 plains anyway

[rodwilson]

Nice to have some TE discussion My first model boiler is well advanced.

The hollow stays on my 2" Burrell Gold Medal Tractor are specified as phos. bronze while other stay are copper. Is there a reason for this? The stays are not threaded and the instruction is to rivet the hornplates on.

The hollow stays I've cut appear rather soft. How can I confirm that they are phos. bronze as I ordered?

If I go down the s.s. bolt road (which I rather like) is there a possibility of the nuts becoming loose is the fire box?

[Deleted]

Gentlemen.
Thank you all for the advice. I have certainly gone a step further. The decision which way to go I will decide later.
I noticed today that the Brunell website has been closed down. Any comment !

[weldsol]

rodwilson
Re stainless bolts and the nuts coming loose, you could give them a light peening

Woodleys.
Just tried their site and it states it is closed due to them not paying the hosting fee

Paul

[jasonb]

You should be OK with either bronze or copper hollow stays, the only reason I can think it states bronze is its a bit easier to drill. My Fowler which is also an MJ Eng design specifies "copper or bronze"

If you tap the stays and then use the nut on the inside as a lock nut it should all stay (sorry) together. Button head socket screws don't look too far off rivits once painted.

Bronze can be quite soft like gun metal does depend on teh exact type, SA660, PB102, Colphos 90 etc.

Jason

[Jim]

The hornplates on my Burrell SCC are bolted to tapped pads on the fire box side. I have a Briggs boiler with a dry sided firebox.
I found that a lot of care was needed when mounting the hornplates to maintain the alignment of the the crankshaft, second shaft and axle bearings. I did some painstaking shimming to ensure it all remained true as the bolts were tightened up.
Good luck with your build the Allchins are lovely looking engines and powerful too.

Jim