Engine rebuild

[gavin comptonParticipant @gavincompton68796]

Hi All
i bought this engine from flebay the other week i have no idea on its age or whats it based on here a few pictures of the engine before i stripped it down.(from flebay)

from looks of things almost nothing has been machined. IE: the bushes and spacers are rolled sheet metal.

.

my plan is to repair any broken or wornout parts and then update the looks of the engine mainly the base. i have notice that the last owner has sanded off the paint from all the parts. this makes them looks nasty so i have desided to repaint them. but i plan on polshing some of the brass etc.

one thing i dont like is on picture two is the two oversized nuts connecting the rods to the things on flywheel shaft (i can't spell the name). what do you all think if i brazed them togeather to do away with the nuts ???

what do you all think ??

thanks

Gavin

[gavin comptonParticipant @gavincompton68796]

[JasonBModerator @jasonb]

I think I would stay with nuts to join the eccentric rods to the eccentric straps but if you can identify the thread used you could use a smaller size nut then drill it out and tap to the existing thread.

The way the strap is shaped to meet the "L" bend in the end of the rod would look wrong if you silver soldered the parts IMHO

[gavin comptonParticipant @gavincompton68796]

Hi Jason

thanks for reply. thread is removeable they are studs. you right about the "L" looking werid. guess im just being picky. i could thread a bit of round bar and then blend the round bar on to the other end of the eccentric rods,if the angle wrong i would sliver solder at correct angle. then again if it not broke………..

i also removed the wood lagging it was rather uneven and unsightly not sure if to put wood back on or sheet metal color matched.

thanks

Gavin

[gavin comptonParticipant @gavincompton68796]

Hi all

here a few more pics

As you can see i changed the color of the flywheel and striped and repainted most parts. during the strip down i found some lagging as in picture one it came from the center of the cilnder plate where the piston rod go though See pic 9 .it i guessed was used to seal the piston rod it looks like hemp and plumbers mate putty ??????.

can anyone ID this for me ? also what would you all recommend as to replacement of this seal ?????.

also in my last two pics are the results of bit of metal polshing

 

Thanks

Gavin

Edited By gavin compton on 09/12/2015 18:24:03

[JasonBModerator @jasonb]

Graphite Yarn would be the traditional material, this is a hemp type cord with what smells like tallow and graphite powder added, not to be mixed up with the modern dry version that does not last too well.

You can get it from most model engineering supplies such as Blackgates, bruce engineering, Reeves, etc.

There is also a modern PTFE version and it is also posible to take plumbers PTFE tape and twist several lengths into a rope but as yours is quite a lareg engine I would not roll my own.

[gavin comptonParticipant @gavincompton68796]

Hi jason

thanks yet again

what one would be best ? the "old" type or the "modern" one ?

Thanks

Gavin

[JasonBModerator @jasonb]

I still like the old type. One advantage is that you can unravel it and get smaller size strands, it also packs down into an almost solid section to fill the packing cavity.

J

[gavin comptonParticipant @gavincompton68796]

Thanks Jason i order some for the rebuild

i also noticed the based is warped there a 10mm twist/lift on front left to rear right. there no screws just two studs clamping the two cross members in place. i had to cut the studs as the nuts and holes was filled with epoxy. inspecton of the cross members showed they are not cut sq. so i can either repair and true up the base or start again,im not sure yet i hate wood work lol.

thanks

Gavin

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Gavin, "it came from the center of the cilnder plate where the piston rod go though" so you can explain it easier, it is known as a stuffing box and the stuff you put in it is refered as gland packing. I'm agree with Jason, I like the old type for the same reason. Nice bit of cleaning, painting and polish, should look good when you've finished it.

Regards Nick.

[gavin comptonParticipant @gavincompton68796]

Hi all

Thanks for that Nick . Before I start putting engine together can I double check with u lot on how to work out amount of power and steam usage/pressure, is it cylinder diameter x piston stroke?. I have some 4mm thick copper tube that's 175mm od that I want to use to make a true cornish boiler (brickwork flues the lot) want to workout what this engine will need to run to see if the boiler in mind would run it.

I also built the new Base today much better now just got fill screws holes in and prep for paint

Thanks

Gavin

Edited By gavin compton on 10/12/2015 23:41:08

[JasonBModerator @jasonb]

Area of piston x twice stroke as its double acting

[gavin comptonParticipant @gavincompton68796]

Hi all

I having trouble with my maths I think dia of the piston is 4.5cm so I worked out area as 15.90cm2???? Timing this by stroke X2 at 13.5 gives me 429.3 now if that's right, I don't think it is how do I then work out stuff like amount of steam needed to run and pressure etc??

Gavin

[gavin comptonParticipant @gavincompton68796]

Well that this project over flywheel and shaft rolled off work bench and broke the flywheel snaped the spokes im rather shocked it broke ,now i got bits of a engine that going to waste.

gavin

[roy entwistleParticipant @royentwistle24699]

get another flywheel

Edited By roy entwistle on 14/12/2015 18:12:56

[gavin comptonParticipant @gavincompton68796]

Posted by roy entwistle on 14/12/2015 18:11:36:

get another flywheel

Edited By roy entwistle on 14/12/2015 18:12:56

i would if i could find one machined i only got a small lathe its not big enough to machine a 8" flywheel

[gavin comptonParticipant @gavincompton68796]

ok so i might of be mistaken as to what size i can turn. i might be able to turn a 8" flywheel. where would people recomend getting a casting from ??

thanks

gavin

[JasonBModerator @jasonb]

If you want to stick with curved spokes then in te Uk you could go with one from a 3" Little Samson traction engine which is 9" dia

Available here

Or Polly will probably supply just a 9" one from their R&B gas engine.

Engineers Emporium have 7.25" and 8.5" curved ones but not shown on their site, they will also machine them

 

From the states you have Martin Model & pattern who do a nice 8" one but postage is not the cheapest.

In Europe there is Atelier who do a 9", TS have a good range but not large curved ones

Edited By JasonB on 14/12/2015 19:17:54

[gavin comptonParticipant @gavincompton68796]

Wow Jason i been googling for past hour and found nothing lol thank you i look into them, yes i would rather stick with a curved buy depends on what about to buy .

thanks

gavin

[Ian S CParticipant @iansc]

Gavin, if all else fails, you could carve one out of a slice of steel, or brass. This is one made of two pieces of hot rolled steel plate about 10 mm thick for one of my hot air engines, the 812 is the weight in grams. Ian S C

[Michael GilliganParticipant @michaelgilligan61133]

Gavin,

A couple of weeks ago we were at the big Tesco store [at Handorth Dean, Greater Manchester] where they were selling-off 10kg cast iron barbell weights for £3 each … regrettably, I didn't buy any but it might be worth you checking for local availability.

MichaelG.

.

Edit: Oh "Bother" … It looks like they were a seriously good bargain.

http://www.tesco.com/direct/v-fit-herculean-2-x-10kg-cast-iron-weight-plates-hammertone/159-1048.prd?pageLevel=&skuId=159-1048

Edited By Michael Gilligan on 15/12/2015 16:15:40

[Ian S CParticipant @iansc]

A source of quality cat iron is an old automotive flywheel, OLD, 4 cylinder truck, tractor, lower the revs, bigger the flywheel. I'v looked at barbell weights, and the ones I'v seen look as they might have blow holes, and some had holes drilled in the rim to correct the weight. Some of them are mild steel with a plastic covering, which ever you look at in sports shops here, its an expensive way to buy metal. It's quite possibly different else where.

Ian S C

[gavin comptonParticipant @gavincompton68796]

Hi All

thank you all for your replys,i ordered a 8.5 inch curved casting from engineers emporium i have to read up on how it correctly machine it only thing is the old one was a 5 spoke new one 6 spoke but at least it look close to how it should. last night i had to re-machine the shaft as the drop damaged the part that sits in the bearing.By the time it was anywhere near round it was to small O.D so i machined a sleeve that i heat pressed onto and machined to correct OD.

i would of make a complete new shaft but i couldn't find a way to remove the eccentrics.

thanks

gavin

[gavin comptonParticipant @gavincompton68796]

hi.

would a displacement lubricator be a good idea on this engine ???. specially as it has a cast iron piston ring ??

the engine has no way to lub the piston currently in fact a lot of this engine has no oil points where i would of thought there would be the only oil points are on the two bearing blocks and piston slides. am i over thinking it all or should the likes of the eccentrics ,crank pin etc have a way to oil them ??

thanks

gavin

[JasonBModerator @jasonb]

Difinately need to lubricate, displacement will do if running on steam, if only on air you will need mechanical methods.

As it's quite a large engine a few oil points won't hurt, a simple way to do them on teh smaller items is to use a No 1 centre drill which will leave a cone to hold the oil and if the pilot hole is not long enough to break through it can be extended with a 1/16" drill

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