The Bucket Foundry

[Flettner]

Yes Will I know both sides, Bruce and Hank, the guy thats wanted the models gone. I sold Hank a gyrocopter some years ago, he crashed it twice, nervous flyer, so he is not too happy sharing the airspace with model aeroplanes. The gyro is long sold (after it's second rebuild) but he now has a modern fast little microlite. Hasn't crashed that yet. Hank and Bruce were in bussiness together at one point but that soured, don't know why. Hanks old gyro is now in Wanganui (H?) still flying but now with a turbocharger attached, approx 160HP. Each to their own.

[husaberg]

Well there is a story that goes with this, some years ago (true apparently) Bruce was approached by an off shore buyer for his pules jet engines. An Arab group, so Bruce contacts the NZ trade embassy to see if there is no problem selling these engines to the Arabs. It seems the NZ trade people contacted the US embassy to see if there would be a problem.
The next morning as Bruce unlocks his shed door he noticed a big black SUV parked near, two guys dressed in black suits appeared out of the morning darkness (Bruce said wearing dark glasses too), pulled their lapels back to display a pair of large hand guns. The story goes that the conversation went along the lines of 'Bad things will happen if you continue to entertain ideas of exporting your engines to Arab states' Bruce was suitably encouraged to drop the idea. I kid you not.

Probably already told this one on ESE.

I don't doubt it for a second.
There was a kiwi who invented a submarine compass during WW2 (ie worked surrounded by metal)he was locked away during the war on sommes island to work on what was described as a "death ray" but actually was more likely radar.
He never got paid for the compass either, despite becoming standard issue for the RN
https://booksellersnz.wordpress.com/tag/victor-penny/
http://www.no8rewired.kiwi/nz-inventions/death-ray/

Some more of Bruce
http://aardvark.co.nz/pjet/scrapheap.shtml

[WilDun]

Some more of Bruce

Very entertaining (the video) - think that Bruce is a 'never say die' type of guy - I'd be a bit worried if he was the opposition and not on my side in an argument!
Bet he'd have one or two ideas on how to construct a burner for a furnace!

[TZ350]

Well there is a story that goes with this, some years ago (true apparently) Bruce was approached by an off shore buyer for his pules jet engines. An Arab group, so Bruce contacts the NZ trade embassy to see if there is no problem selling these engines to the Arabs. It seems the NZ trade people contacted the US embassy to see if there would be a problem.

The next morning as Bruce unlocks his shed door he noticed a big black SUV parked near, two guys dressed in black suits appeared out of the morning darkness (Bruce said wearing dark glasses too), pulled their lapels back to display a pair of large hand guns. The story goes that the conversation went along the lines of 'Bad things will happen if you continue to entertain ideas of exporting your engines to Arab states' Bruce was suitably encouraged to drop the idea. I kid you not.

I remember this, talked about a bit in the media at the time.

[Flettner]

Patternmaking is therapy, especially using bits of wood from old things that would otherwise be thrown out, I like that. Mum's old ironing board, best use for it. What good is an ironing board anyway? I'm not sure I've ever seen one used. With wood and bondi, there are no mistakes just continual refinements.

[ken seeber]

Slider update. Well old mate did a trial O ring groove machining. Looks ok. Other than the fact that he used a ball end cutter rather than a flat bottomed tool. Also scabbed a reed block and carb adapter. Getting there, but these things seem to take a lot of time to get done. Not all though, as this aging process seems pretty snappy.

[Flettner]

Ken, good, I was just about to say, send the cylinder back to me and I'll cut the oval / circular o ring groove on my new milling machine attachment just made to do this very job. I'm am so convinced that this is a good idea I've decided to make this o ring groove attachment as there will be a few to do in the future I think. Not just FOS, I think this will work great also on a stanadard cylinder but we are yet to see.

[Michael Moore]

A guy in Sweden just posted some info on Alloy Avenue about 3D printed patterns /castings for a new turbine engine for his LSR bike

http://www.alloyavenue.com/vb/showth...inted-patterns

The new engine will be about 2X the size of the one he's been running.


Jeff has been busy traveling to the AHRMA nationals in the middle part of the country and I think normal maintenance chores on the bike have kept him from doing anything foundry related (though the F37 cylinders that were cast do seem to be working well).


I'm throwing in the towel on the wooden pattern for the Webco CT-1 replica head. There's waaay too many square inches of fin to seal/sand/seal/sand/seal/sand. Wooden patterns might be OK to deal with for less involved projects but I'm tired of them for this one. Maybe I can revisit the wood fin stock for some future pattern.

So the plan now is to CNC the upper and lower parts of the pattern from machinable wax, pull silcone rubber molds off of those, and then cast urethane patterns (probably from Freeman's Repro One).

There's been a few stumbling blocks along the way.

First, I had a lot of "let's start over again - again" moments with the modeling, but I think I've got a pretty good idea of how to do fins now. I can get a basic finned head very quickly, it is all the little details like fillets, adjusting fin locations, filling in between the fins for the spark plug, etc that provide a lot of aggro.

It may be hard to see but the way the Webco head is designed there is a boss on the top section filling between the three center fins for the spark plug. The other flat surfaces at the fin-base level get spot-faced for the cylinder head nuts. The Webco had a truncated-cone plus squish combustion chamber which is pretty deep compared to the more modern hemi+squish I plan on using, but that will just mean countersinking a little deeper for the plug.

Second, is I decided to order a training package for my RhinoCAM software (for the CNC code) because I was not finding it very intuitive with the minimal documentation it comes with. After a couple of weeks the package with the DVD containing the videos and expanded manual arrived -- except when I opened the DVD case it was empty. So instead of spending this weekend studying the material I will have to wait until a replacement arrives (probably Tuesday).

Third, I ordered some tapered ball-end mills on 01 June -- 1/8" nose radius, 2.25" LOC, HSS x 3 flute, in 1, 1.5, 2 and 3 degree/side tapers. I'll be using the 1 degree on these fins to let me finish the gullet at the fin base and the sides of the adjacent fins in one pass. A week after placing the order I followed up to get a tracking number because I'd expected to have received the parts a day or two before. I was told "oh, they won't be able to make those for a week or two". It would have been nice to have been informed of that without needing to prompt them. After another week they are now expected to ship Mon/Tues of this next week. By the time they arrive it will have been close to four weeks since the order was placed. It is a good thing the wax is supposed to cause little to no wear on the cutters, because I'd prefer to not have to order more of them.

On the bright side, with the delays I've had more time to look at my 3D model in Rhino and think about the machining operations and fixturing.

Perhaps by mid-July I'll have some urethane patterns on hand.

cheers,
Michael

[WilDun]

So the plan now is to CNC the upper and lower parts of the pattern from machinable wax, pull silcone rubber molds off of those, and then cast urethane patterns (probably from Freeman's Repro One).

I ordered some tapered ball-end mills on 01 June -- 1/8" nose radius, 2.25" LOC, HSS x 3 flute, in 1, 1.5, 2 and 3 degree/side tapers. I'll be using the 1 degree on these fins to let me finish the gullet at the fin base and the sides of the adjacent fins in one pass.
cheers,
Michael

Michael, how will you go about milling the deep fins in wax - are you planning to mill those straight in from the sides, or do it in smaller incremental depths with your tapered cutters?
I just ask because it might be a little difficult because of the thickness (or is it thinness) of each fin and the fragility of the wax - maybe, I'm being a bit neurotic, ie not having tried it myself (but interested in trying it) - just a thought........

[Michael Moore]

WilDun, the fins will be done in incremental steps in the Z axis.

The more stickout of the cutter, the more flex for a given cut and feed. So it looks like the first 3/4" can be done with 1/4" EMs in 2 or 3 passes, while the last ones at 2.25" below are in .015" or so. I'll use regular square end cutters as far as I can since ball end cutters have the middle of the ball with effectively zero motion and probably just mush the material out of the way at the very tip/center of rotation. If you need a radius in the cut many times an EM with a corner radius is a better bet than the ball-end, because it keeps the SFM up. But for some things you can't avoid using a ball-end EM.

I bought some more ER collet chucks and 1/4" EMs in various OAL/LOC. I'll probably have 4-5 different EMs with varying stick-outs before the tapered EM is called into play. Though the final cuts may only be .010-.015" deep, since they'll be cutting nearly full length on the sides that is plenty of load on them.

I bandsawed a slice of wax (roughly .187") off of a block I have. It is not too hard to snap with moderate finger pressure, so I'll try and leave about .005" of stock for the final passes on the sides of the fins. I think the gullets will be the determining factor as that is the hardest bit of cutting due to the problems of no SFM at the tip.

I figure the wax is treated as recyclable after I get a good rubber mold from it If it breaks while being removed, no big deal, it all goes into the "to be re-melted" tub. With a good rubber mold a large number of urethane patterns could be made, though I anticipate making a few heads for my own use and then maybe doing another 5-6 or so to see if I can recoup a little money by selling them to other vintage racers.

That's the problem with vintage racing, there's only so much demand for these parts so you've got to do them for your own use and if you can peddle a few extras, that's all found money (even though you are actually still losing money, you aren't losing quite as much).

cheers,
Michael

[Grumph]

That's the problem with vintage racing, there's only so much demand for these parts so you've got to do them for your own use and if you can peddle a few extras, that's all found money (even though you are actually still losing money, you aren't losing quite as much).

cheers,
Michael

You're not wrong about the economics of vintage racing...I just sold the last Aermacchi replica frame i had hanging round here. That makes 12 made and sold. Which is market saturation....I had a brief talk with Sammy Miller some years back at a Classic meet here in NZ about the replica frame business. we agreed he had a huge advantage in name recognition which meant he would keep selling frame kits as long as he cared to make them.
FWIW, 3 kits to Australia, 2 to Canada, balance here in NZ. More than I originally thought I'd make.

[Flettner]

I figure the wax is treated as recyclable after I get a good rubber mold from it If it breaks while being removed, no big deal, it all goes into the "to be re-melted" tub. With a good rubber mold a large number of urethane patterns could be made, though I anticipate making a few heads for my own use and then maybe doing another 5-6 or so to see if I can recoup a little money by selling them to other vintage racers.

That's the problem with vintage racing, there's only so much demand for these parts so you've got to do them for your own use and if you can peddle a few extras, that's all found money (even though you are actually still losing money, you aren't losing quite as much).

cheers,
Michael

Ha ha ha , recoup costs, yer right.

[ken seeber]

Slider update. Grooves now in cylinder to accept O rings that surround each of the 3 exh ports. As we had to get some laser cutting done, we also did some exh flanged and spring hanger brackets. Little bit of work req'd on cylinder then off for plating.

[Flettner]

Found the wifes old camera, who remembers these beasts, fit for purpose. Saved it from heading off to the scrap yard 20 years ago. fitting the 250F clutch to the 250T gearbox. Clutch cover pattern is under construction, this weekends job to finish it. Water pump will be in the clutch side case run off the ballance shaft, these engine cases are water cooled.

[Michael Moore]

Shapers are cool! I had a Rhodes 9" from the early 1920s but it was just too small for the things I'd want to do (like fitting a good-sized rotary table as in your photo). I've got a lot of shaper info on my website:

http://www.eurospares.com/shapers.htm

It is nice to see a shaper being put to work. Most people don't need a shaper, but when you've got a shaper job, you need a shaper.

Nurserys probably need to have shapers, the sound of a shaper peeling off chips should put a baby to sleep for an entire night, they are so soothing/mesmerizing.

cheers,
Michael