Centre of flywheels and lateral centre of weight for a twin engine.

[Monkeypants]

thanks for the offer Howard, and you're right, Hastelloy makes a rod for welding mild steel to SS. I ordered a 2" bung and cap in 316 SS today, it should be here shortly.
If I hadn't already ordered this 2" set, the 1.5 inch set with Al. cap and O ring seal in the link Bruce provided would be a good choice.
The set I am getting relies on pipe thread to seal, so some pipe gunk will be needed, especially with stainless as it doesn't mush together like steel or brass.

 

[bmetcalf]

Be aware of SS threads' desire to gall and seize. Johnny Mac may have some pipefitter tricks or special sealant to suggest.

 

[Howard]

Be aware of SS threads' desire to gall and seize. Johnny Mac may have some pipefitter tricks or special sealant to suggest.

Too right! I've had to cut off bolts on outdoor installations where the original fitter has not used copper slip, and the nut wouldn't come off or tighten. One of the reasons I suggested gearbox cover, not a SS plug - copper is another option for the plug.

H

 

[Monkeypants]

I had similar problems with stainless years ago. I bought some SS bolts to be used in dock construction. This is a dock that I partially disassemble and bring out of the water every fall, then reassemble and put back in the water in spring.
I tack welded some of the stainless nuts to large washers to make things easier. This works fine with steel nuts and bolts, but didn't with the stainless, every one galled. With stainless threads, the thread won't come out of it like steel might, the more you turn the worse it gets. In the end I made up some nut/washers and ran a tap thru. The bolts have been in and out about 20 times now, no problem.

I have quite a bit of SS on the OZ Rapide and have had no problems. If I ever feel a bit of resistance in the threads, time to stop, back the thread off and correct the problem.

 

[Pushrod Twin]

Nice one guys. We have all had dramas with SS binding, mine was honing Breeze Hooks for helicopter rescue winch hook parts we manufactured in house. Hand fitting 2 parts with only tenths of a thou clearance & honing oil instead of the full 3-5thou with antisieze, oops! in the bin!
Apart from my jests about cleaning out bigend detritus, one of the real reasons I wanted access in there was to clean out welding/ brazing scale. I felt that was likely to contribute to bigend failure. I guess you will be gas purging during TIG welding, but you will now be able to acid etch inside with relative ease.
I have posted pics of my efforts, if they are of any interest to you, under Egli Replica. R.

 

[Monkeypants]

Lovely job , PT. What sort of big bore setup did you use?

I haven't been able to make much progress lately, too many interuptions and a couple of interesting paying jobs, one of which was welding a $5,000 casting on a German built bakery machine that had some problems. I don't know if I should have been trusted for that one, but it turned out OK and the machine is back in production.

The little bobbins in the photo are some weld-in pieces I made this AM for the frame to swingarm bolt attachment. Other than that I made the front motor mount tangs and tacked them in place after much aligning of things.

I have bungs coming from 2 sources, the small O ring type from the BungKing link that Bruce provided, plus a 2" pipe thread one sourced locally.

Glen

 

[Pushrod Twin]

Looks good. Rear mounts? I expect you are aware of the folk lore concerning rear mounts? In case not; I have read, & heard from a variety of sources, that Fritz & the Slaters never fitted rear head to frame bolts. Supposedly for the same reason the factory slotted the UFM, engine expansion stressed & cracked things. Confirmation from people like Howard & David D would be good. I can confirm that some NZ frames were built with no rear brackets at all based on these theories, just had tidy triangular gussets from outside of spine to down tubes. Because of a bolt on gearbox fixing, I chose to include brackets, but will slot holes & not tighten bolt excessively. I also cut the bottom out of the spine between the rear mount tangs & created a small sump for the oil pick up, I calculated that under heavy braking there could be enough forward surge to leave the back of the tank emptyish. I know standard Eglis take their oil from the front, but I wanted mine to be more like the standard Vincent set up, for better or for worse! R.

 

[bmetcalf]

never fitted rear head to frame bolts. .

I thought I remembered that from an Egli at Shadow Lake '77, but on jtan, knowledgeable people said no, they had a slotted clip and head bracket with bolt. I forget if David weighed in on this.

 

[Howard]

They're not that knowledgeable Bruce, mine never had a rear bolt, and I've never felt the need for one - Owners of real Vin frames go into cold sweats when they see there's no bolt. There's a rear head bracket that's a snug fit between 2 frame brackets, the front head has the standard Vin stud with necked down nuts and locknuts.

Roy, my frame has the oil feed at the back, and return at the front, I don't think oil surge is a problem, but can't see a problem with a small sump anyway.

H

 

[Monkeypants]

I'm planning on bolting the rear up the way a standard Vincent is done and will follow the tightening procedure in Rider's handbook. That has worked OK on the OZ Rapide for 63 years so far!
One concern is the al. head brackets on the Glenli.
I got thinking about the heat expansion of the head brackets (beyond the exp. of the hanger bolt) causing the rear mount to get tight and prevent the slide. But then, by the time much expansion of the head bracket has happened, the slide should also have happened, so maybe it's nothing to worry about.
In any case, the cross bolt will be stainless which has a thermal expansion coefficient approaching that of al.

Glen