Petter Pins

Because Petters eat their gudgeon pins, I've bitten the bullet and ordered a batch for delivery around Easter. I ordered a few spares for 1 1/2, 3, and 5
so if you need one please contact me direct. The final price is to be confirmed but it will be around 25 which is a fraction of the one-off cost. regards
--
Roland Craven
nr Exeter Devon, UK
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Roland and Celia Craven wrote:

ordered a

3, and 5

is a

Hello Roland and Celia, I was looking at the picture of the ''0GLE'' crankcase, would I be correct in assuming that all or most of your engines,are reconditioned as show pieces in working condition,and that this same criteria would apply to most other collecters of old Stationary engines. You mentioned WELDING.as a large chunk of the side of the crankcase was missing,and if I am right, it was badly cracked,[did this damage cross any oil gallerys ]?...how did you repair it? did you weld in a patch and weld the crack? My reason for asking these questions is that before I retired I for 17 years overhauled and tested most sorts of engines in the Transport industry. In the very early days engines would come in for repair, cracked perhaps the whole length of the side of the crankcase possibly affecting oil galleries as well.Or maybe a thrown connecting rod smashed a bit out of the side the size of a hand. The CRACK.was stitched with 1/4 copper rod,process involved drilling and tapping into the crack,screwing in a bit of the rod then drilling 1/2 into copper rod and 1/2 into crankcase,this process was continued until the CRACK was STITCHED by one solid line of screwed in copper rod,[sealant was used on the threads as each piece was screwed in],A water pressure test was then applied to both water and oil gallerys, and the copper stitching PEENED with a round nose hammer if any leaks showed. Where a piece of the case was missing,this was repaired using ANNEALED 1/8 COPPER plate moulded to the contour of the crankcase at the point of damage, then drilled tapped and screwed with cork gasket. As most of these engines were relatively larger ,this method although time consuming apparently avoided the risk of distortion. I would appreciate your comments, All the best for now,and keep up the good work, John.
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Yes I like to get my engines into full working condition, and I work them, but not always to "show" standard. It all depends on what they look like. I've bought Petters with MS pins flopping about, like a sausage up North Street, and seen Silver steel pins fail so will only use properly made replacements The Ogle damage is to the water jacket only so is not critical. However the jacket was full of cement like scale and the CI has suffered sea-water attack. Its going to need a whole circle cut out and a ring brazed, or perhaps stitched in. The whole engine is such a challenge that it keeps going backwards in the queue :-( ttfn Roland
I was looking at the picture of the ''0GLE'' crankcase, would I be correct in assuming that all or most of your engines,are reconditioned as show pieces in working condition,and that this same criteria would apply to most other collecters of old Stationary engines. You mentioned WELDING.as a large chunk of the side of the crankcase was missing,and if I am right, it was badly cracked,[did this damage cross any oil gallerys ]?...how did you repair it? did you weld in a patch and weld the crack? My reason for asking these questions is that before I retired I for 17 years overhauled and tested most sorts of engines in the Transport industry. In the very early days engines would come in for repair, cracked perhaps the whole length of the side of the crankcase possibly affecting oil galleries as well.Or maybe a thrown connecting rod smashed a bit out of the side the size of a hand. The CRACK.was stitched with 1/4 copper rod,process involved drilling and tapping into the crack,screwing in a bit of the rod then drilling 1/2 into copper rod and 1/2 into crankcase,this process was continued until the CRACK was STITCHED by one solid line of screwed in copper rod,[sealant was used on the threads as each piece was screwed in],A water pressure test was then applied to both water and oil gallerys, and the copper stitching PEENED with a round nose hammer if any leaks showed. Where a piece of the case was missing,this was repaired using ANNEALED 1/8 COPPER plate moulded to the contour of the crankcase at the point of damage, then drilled tapped and screwed with cork gasket. As most of these engines were relatively larger ,this method although time consuming apparently avoided the risk of distortion. I would appreciate your comments, All the best for now,and keep up the good work, John.
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Talking to Phillip Gallimore, he remembers that the replacement gudgeon pin on his Scott SE (which I now have) was made from silver steel. I wondered at the time if this was an entirely appropriate material - I take it you would say not?
--
NHH



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Nick H wrote:

gudgeon pin

wondered at

would
I'm rather jumping in on Rolands thread here, but....silver steel has the advantage of being accurately sized. Its just about OK for making a gudgeon pin for a four stroke engine which is not going to be driving anything. If you try to harden it, it will get too brittle and in all probability snap, which can cause a lot of damage. In its unhardened state, its not *really* hard enough, and tends to wear fairly rapidly. I would't consider it at all for any of my Petters, which are working fairly hard on the rallyfield. The small end is of course under greater load and conditions of borderline lubrication in a two stroke, all the more reason for using a proper pin
Regards
Philip
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Does anyone know what the pins were originally made from? I would have thought that silver-steel, hardened and then backed-off a bit would be fine. Maybe the problem is that it is not particularly easy to accurately temper the hardened steel without oven facilities. I can't really imagine that the original 1920's pins were anything more exotic than a good grade stubbs or silver steel if that - maybe I'm wrong.
Regards
Mark
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Mark, You cannot harden silver steel and back it off, as Philip pointed out it is not a tough material when soft and becomes like glass when hard, it has no tensile strength when hard and in my experience appears to get harder if treated again. Something like EN 24 with a good case hardening would be a safe bet, hard wearing on the outside and soft in the middle.
Martin P
snipped-for-privacy@ukonline.co.uk wrote:

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On Thu, 3 Mar 2005 21:37:58 -0000, "Campingstoveman"

Nickel-Chrome steel such as K.E. 287, case-hardened 0.025" to 0.035" is the recommendation in Phil Irving's book, "Tuning for Speed".
Peter
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Good point Martin,
I'd still like to know what they originally used - the steel clasifications (EN Nos.) that we know and love (and have been obsolete since the '70's) came into being in the '40's. Were there equivalent standards before this or were pins and the like just unreliable?
Mark
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The drawings simply call for "best mild steel", they have a thick case and are reliable. After 80 years or so most are simply worn out. Not much help to you I fear. regards Roland
clasifications

or
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fine.
the
My trepidation arises from tales of vintage motorcyclists being deposited in the road due to the failure of fork spindles made from this material. Could be poor heat treatment of course. I think the Scott pin has been left soft (that's what file file test says anyway) and is solid so hopefully it won't break, but wear could be a problem - but probably not for me!
--
NHH

http://community.webshots.com/user/n_highfield
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It was somewhere outside Barstow when "Nick H"

I'd expect it to be as good as an original. Probably rather better, if these things are prone to failure. However I'd have it commercially heat-treated, not just heated up a bit and dunked in URHB
If you want a really good one, there are any number of commercial alloys that are somewhat better (I don't think you'd notice) and a production process that involved grinding after hardening. Of course this would cost coppers in mass production, a fortune as a one-off.
How big are these things anyway ? Is silver steel really that easily obtained in such sizes ?
(URHB - urine of a red-haired boy - traditional folk material over in rec.knives)
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wrote:

pin
at
Don't know about Petter pins, but I don't think Scott ones are prone to failure. In the motorcycles it is the piston bosses which take most of the wear and when the death rattle becomes too bad, the usual salvage action is to bore the piston bosses os, loctite in a p-b bush and ream to original spec. On my SE, both bosses and little end have both been bored os and a new gudgeon pin made to suit. Phillip did say that this work was carried out by an 'engineer' and he believed that silver steel was used. I don't know if it recieved any heat treatment but it is certainly not glass hard.
BTW What has Barstow got to do with the price of fish? All it means to me is part of a typically odd song title by The Residents:-
http://www.rzweb.net/app/lyrics/finger.html#barstow
--
NHH

http://community.webshots.com/user/n_highfield
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Just for interest. When I collect my professionally made pins I'll ask what they think of Silver Steel as a pin material. ttfn Roland
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Roland and Celia Craven wrote:

The induction precision ground bar from the likes of SKF has made the job easier especially with the advent of the hollow bar, beats boring out the centre, that my supplier sells by the mm keeps the outlet down to a minimum.
Tom PS the idea of silver as a gudgeon pin, doesn't enthrall me.
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Too late now, but would it not have been possible to acquire a couple of pins from an automotive piston that were approximately correct and make bush and boss to fit?
regards,
Kim Siddorn.
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Nope and don't think I didn't look long and hard. How many modern pins have a peg hole and two oil holes. ttfn Roland

bush
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Ah. I should have known better ;-P
regards,
Kim Siddorn.

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Kim Siddorn wrote:

The problem is that modern gudgeon pins are short and fat, whereas old pins tend to be long and thin. And therein lies the problem :-(
Regards
Philip T-E
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To illustrate Philip's point: for the last three years the local reconditioners have saved all the pins they remove. Its a LARGE pile and there is not one I can use for any old engine. (Actually that's a fib- there is one that will do the Ogle :-) ttfn Roland

bush
pins
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