The Bucket Foundry

[Michael Moore]

Here are some useful videos for rubber/urethane press forming. It looks like 60-90 Shore A is used for the urethane forming pads.

http://www.eaavideo.org/video.aspx?v=1277219627001

3/8" sides, 1/2 bottom, laminated chunk o' rubber, old inner tubes

The following are a few videos from a series on constructing a home-built airplane:
https://www.youtube.com/watch?v=EMlbOkrVxZM
https://www.youtube.com/watch?v=EWGAIVDpDLc

60 Shore A, correcting for spring-back

Quintus Technology videos:
90 shore A throwpads (presumably urethane)

part 1

https://www.youtube.com/watch?v=RA_a0pD5-UU

part 2

https://www.youtube.com/watch?v=RhG8gISbWMA

part 3

https://www.youtube.com/watch?v=mUSljM05pzo

[ken seeber]

Ages ago, we did a cylinder that was going to double the power output of 2 strokes. This (only) had two exhaust pipes, unlike today where 3 is the new norm. These were hydroformed. As MM said, there are 2 ways to do this, one being to do an edge weld, the other being to roll the edges and do a butt weld. We chose the former, as at the time didn’t have anything to effectively roll the edges around. Did a bit of a calc on the material that was to be “lost” in forming the resultant seam and simply added this to the design size.
Bends certainly did overbend and the 30% allowance sounds about right.
There were wrinkles which, to some extent could be hammered down whilst under hydraulic pressure, the surface was far from flat. No probs, just fill it with shop air pressure (around 120 psi) and then locally heat with an oxy torch. Male wrinkles could be easily flattened and female wrinkles would expand out and then blended with heat and hammer.
Without any appreciation of the possibility of accelerated mortality, we decided while the torch was burning and the pressure was still on, that it’d be interesting to see what might happen if one locally (over)heated a small area. No big deal. The target spot firstly went red, then whitish and then just a small Mt Vesuvius of around Ø5-6 mm. With the cool escaping gas, it cooled pretty quickly. Certainly no tearing or splitting from the “stress raiser” spot.

[ken seeber]

Whoops, here's the pics:

[Flettner]

Whoops, here's the pics:

Bugger that, I won't be showing off my pipes then That looks real nice Ken,

Frits, when the Super Charged Honda 100 was finally abandoned and I saw the writing on the wall, if you can't beat them join them, the first thing I built was a cone roller. One of the useful things I've done with my life
I spent a bit of time trying different pressing methods but finally just gave up and made my pipes as straight as possible.

[Frits Overmars]

Ages ago, we did a cylinder that was going to double the power output of 2 strokes.

A teaser if ever there was one, Ken. I hope you don't mind me lifting a tip of the veil .

[Flettner]

Ok you press tool junkies here is a rough arse press tool.
This is to make a tuned induction for the four port Subaru EA81 engines I build up for Autogyro's. This tool was made years ago (pre CNC) and cunningly as you can see the curved end swaps around for left and right hand pressings. Curve not tapered but straight section is. Pressings are in 1.6mm alloy and welded together via the seam, if all works to plan you don't even need filler rod.
Center plenum chamber is made in a large press tool (CNC machined). I haven't pressed any for a while but I seem to remember it takes a good 60 Tons. All seam welded construction, finished product weighs less than half the original (about a third ) and together with the four port heads I make (and a special cam) boosts the engine from 72 HP to 130 HP (NA), no extra rev's just much higher BMEP via better cylinder filling. There is a lot of effort building up these tools but in the long run when finished well worth it.

[Ocean1]

Ok you press tool junkies here is a rough arse press tool.
This is to make a tuned induction for the four port Subaru EA81 engines I build up for Autogyro's. This tool was made years ago (pre CNC) and cunningly as you can see the curved end swaps around for left and right hand pressings. Curve not tapered but straight section is. Pressings are in 1.6mm alloy and welded together via the seam, if all works to plan you don't even need filler rod.
Center plenum chamber is made in a large press tool (CNC machined). I haven't pressed any for a while but I seem to remember it takes a good 60 Tons. All seam welded construction, finished product weighs less than half the original (about a third ) and together with the four port heads I make (and a special cam) boosts the engine from 72 HP to 130 HP (NA), no extra rev's just much higher BMEP via better cylinder filling. There is a lot of effort building up these tools but in the long run when finished well worth it.

Reckon you'd press 1.6mm mild steel in that?

And how do you weld the alloy seams? TIG? Purged?

[Flettner]

Reckon you'd press 1.6mm mild steel in that?

And how do you weld the alloy seams? TIG? Purged?

Yes tig, no purge, not needed with the seam welding. The male half of the curved press tool is the one I poured from zinc, it's lasted well. Here is one manifold running on an EA 82 , home cast twin cam heads, cams, and all the other rubbish that goes with a fourstroke engine.

[WilDun]

Yes tig, no purge, not needed with the seam welding. The male half of the curved press tool is the one I poured from zinc, it's lasted well. Here is one manifold running on an EA 82 , home cast twin cam heads, cams, and all the other rubbish

Neil, in the EA 81 version did you retain the pushrod operation?

[Drew]

Neil, in the EA 81 version did you retain the pushrod operation?

Not by the look of the cam wheels and belt.

[WilDun]

Not by the look of the cam wheels and belt.

Drew, that is an EA 82, which I think was already OHC.
I think the EA 82 may have been basically an EA 81 already modified (from pushrod) to OHC. ......... then Neil got it to actually work properly!

[Drew]

Drew, that is an EA 82, which I think was already OHC.
I think the EA 82 may have been basically an EA 81 already modified (from pushrod) to OHC. ......... then Neil got it to actually work properly!

Oh yip. I get what ya mean.

[Flettner]

EA 81 push rod head original Siamese port, After market push rod head with four ports, my second attempt at a head but for the EA 82. Subaru had an ugly single cam Siamese port head so I thought a quad cam four valve twin plugs per cylinder might be the go. Built an flew two engine's but get too expensive to build

[Flettner]

Another view, EA82 and EA81

EA82 engine with quad cam heads

[Flettner]

Look at all that nasty complexity. This is the engine where I lost all respect for fourstrokes. Gave them away to a guy down in Christchurch who was going to run one in a classic rally car. Don't know what ever happened to them?