The Bucket Foundry

[TZ350]

That's it.
Attachment 304245

I would like to know more about this generator stator and flywheel and where to buy them....

[Muciek]

Ebay and chinesee scooter stator. They are here (in Poland) cheap as chips You can get stator and flywheel for 15$. Propably in Your case taper machining will be necessary.

[husaberg]

http://i1056.photobucket.com/albums/...ps14c5c5a6.jpg

Like that?

I would like to know more about this generator stator and flywheel and where to buy them....

Ebay and chinesee scooter stator. They are here (in Poland) cheap as chips You can get stator and flywheel for 15$. Propably in Your case taper machining will be necessary.

That's what I was thinking it was too.Neil?
Or is it a std late Honda single alternator off say a crf150/230

[husaberg]

So no bastard is to pour scorn on my photoshop.

here is the basic layout I have preliminary decided on until I get an unmolested frame I can't set the front mount position.
Once that is decided I have a couple of datum points to work within.

I hope to have the balancer and the water pump both on the already busy clutch side with the generator here as well.
The disk entry on the output side Reversal of the Rotax Aprilia design.

I was worried with the water entry going on top and under the engine but seeing as it didn't worry Derbi and Aprilia.


Balancer shaft.

[Flettner]

I get those flywheels from Wobbly, I've used one in my Kawasaki for a few years now, seems to work ok. I have had one of the regulators fail.

[Michael Moore]

I'd like to start off by thanking Flettner for sharing the great information on foundry practice. I've found it very informative and have pointed several friends at this thread.

My friends and I have been thinking about having some items cast, but the first (and most local) foundry I went to with a couple of aircooled 2T cylinders in hand as examples quickly told me that was going to be outside their comfort zone. That's too bad as they are the only one whose website made any mention of being willing to work with loose patters one-offs for hobbyists. The others are 30-60 miles away and my impression is that they are more interested in commercial/production work so I haven't made a trip to visit them yet.

One of the things we are interested in is replicating some VMX aftermarket 2T cylinder heads and tomorrow I'll organize a couple of photos and questions about how best the molds might be fed. We can handle making patterns, but we don't have anyone to advise us on the sprue/gates/riser system. Perhaps that is something the better foundries might do, though I suspect they won't do it for free.

I've got a large heat treat oven with programmable control that goes to 2000F.

http://www.paragonweb.com/HT22D.cfm

It requires 240v 30A single phase and is rated at 7.2 KW. It is 13.25" high on the inside which would accommodate a 16 pound (aluminum) crucible (9.3" tall). I have the impression that it is best to melt the aluminum quickly so it has the least amount of time to oxidize. Do you have any idea if the HT oven might do the job quickly enough for oxidation to not be a problem? My house is an urban area where the lots are 25 feet wide, so gas furnaces and smoke/noise are not a good idea. I can't say that I'm keen on the thought of what would happen in the garage if there was a crucible failure in the oven or while the crucible was being carried to the back yard. Maybe it would be best to stick with making patterns and farm out the rest of the process.

Earlier there was a post in which someone asked about buying pieces of wrought material to machine parts instead of casting. While NZ seems to have better access to foundries, here in the US we seem to do better on the availability of large offcuts at reasonable prices. I just bought two pieces of 6061-T651, 3.5" x 12" x 12" off of eBay for US$160 each, including shipping to me. Since I have a CNC mill and do a 3D model anyway it makes machining a one-off vertically-split crankcase look more economical than dealing with a foundry.

cheers,
Michael

[husaberg]

I'd like to start off by thanking Flettner for sharing the great information on foundry practice. I've found it very informative and have pointed several friends at this thread.

My friends and I have been thinking about having some items cast, but the first (and most local) foundry I went to with a couple of aircooled 2T cylinders in hand as examples quickly told me that was going to be outside their comfort zone. That's too bad as they are the only one whose website made any mention of being willing to work with loose patters one-offs for hobbyists. The others are 30-60 miles away and my impression is that they are more interested in commercial/production work so I haven't made a trip to visit them yet.

One of the things we are interested in is replicating some VMX aftermarket 2T cylinder heads and tomorrow I'll organize a couple of photos and questions about how best the molds might be fed. We can handle making patterns, but we don't have anyone to advise us on the sprue/gates/riser system. Perhaps that is something the better foundries might do, though I suspect they won't do it for free.

I've got a large heat treat oven with programmable control that goes to 2000F.

http://www.paragonweb.com/HT22D.cfm

It requires 240v 30A single phase and is rated at 7.2 KW. It is 13.25" high on the inside which would accommodate a 16 pound (aluminum) crucible (9.3" tall). I have the impression that it is best to melt the aluminum quickly so it has the least amount of time to oxidize. Do you have any idea if the HT oven might do the job quickly enough for oxidation to not be a problem? My house is an urban area where the lots are 25 feet wide, so gas furnaces and smoke/noise are not a good idea. I can't say that I'm keen on the thought of what would happen in the garage if there was a crucible failure in the oven or while the crucible was being carried to the back yard. Maybe it would be best to stick with making patterns and farm out the rest of the process.

Earlier there was a post in which someone asked about buying pieces of wrought material to machine parts instead of casting. While NZ seems to have better access to foundries, here in the US we seem to do better on the availability of large offcuts at reasonable prices. I just bought two pieces of 6061-T651, 3.5" x 12" x 12" off of eBay for US$160 each, including shipping to me. Since I have a CNC mill and do a 3D model anyway it makes machining a one-off vertically-split crankcase look more economical than dealing with a foundry.

cheers,
Michael

Michael someone in the US is doing some DG I think heads MR Wobb;y here in NZ had one. (Oh it was Webco)
I guess what you want looks like one of these though. Click on the arrow after the user name to follow the link

There is a tiny bit of gold buried in here, can you find it Rob...

That air cooled would have blown to pieces even on Methanol with that sort of com - insane.
I mentioned awhile ago a project I was doing for the Webco type RD series of heads, 250,350,400
The prototype has just been cut on the CNC, so I could be able to supply blanks, or a special design with precut toroidal chamber, quite soon.

That air cooled would have blown to pieces even on Methanol with that sort of com - insane.
I mentioned awhile ago a project I was doing for the Webco type RD series of heads, 250,350,400
The prototype has just been cut on the CNC, so I could be able to supply blanks, or a special design with precut toroidal chamber, quite soon.

http://www.kiwibiker.co.nz/forums/at...3&d=1405899033

That air cooled would have blown to pieces even on Methanol with that sort of com - insane.
I mentioned awhile ago a project I was doing for the Webco type RD series of heads, 250,350,400
The prototype has just been cut on the CNC, so I could be able to supply blanks, or a special design with precut toroidal chamber, quite soon.

Ha Ha, amazing - guess who just got the job to do the solid modelling for CNC machining new replica head chamber shapes made on the Webco dies.

[Michael Moore]

Since I only found the forum yesterday I've not gotten anywhere near that part of the ESE thread yet but I'm working on it!

I was able to get a Webco head for my CT-1 VRR project but I've got to pull the helicoils out and weld up the spark/compression release holes and the chamber so it can be redone. One of my friends would like a Webco head for his DT-1. Milling deep and moderately close-spaced fins is not something I want to do unless it is a parallel fin head (like the CT-1) and I can find an affordable large OD (about 8-9") cutter, and even then I'd prefer to not have to do that. Having new castings done seems like a much better plan.

cheers,
Michael

[Grumph]

Michael - a large dia, thin cutter is the least of your problems - HSS skillsaw blade works on alloy just great. Replacements are cheap too...Even available with carbide tips attatched.

Peter Jones of ChCh NZ - Oyster on here - has made replacement barrels for a very unusual Kiwi special he rescued which uses a chainsaw based twin 2T motor. The finning was cut with i believe a slightly modified skillsaw...For gaps wider than one blade thickness, simply gang one or two more blades.

[husaberg]

Michael - a large dia, thin cutter is the least of your problems - HSS skillsaw blade works on alloy just great. Replacements are cheap too...Even available with carbide tips attatched.

Peter Jones of ChCh NZ - Oyster on here - has made replacement barrels for a very unusual Kiwi special he rescued which uses a chainsaw based twin 2T motor. The finning was cut with i believe a slightly modified skillsaw...For gaps wider than one blade thickness, simply gang one or two more blades.

i had posted this before.
The Begg workshop was obviously a hot bed of special building.

Gee that took some finding.............I not kidding that was like 15 minutes gone forever.........
http://www.kiwibiker.co.nz/forums/sh...post1130433397

[TZ350]

HSS skillsaw blade works on alloy just great. Replacements are cheap too...Even available with carbide tips attatched.

Here you go......

Attachment 304307

Needed to trim the cylinder head heat sink, I don't have a mill so got the trusty old skill saw out.

Attachment 304308 Attachment 304309

[Flettner]

Here are some copy cast heads. Just filled up the original holes in the head and cleaned between the fins with fine wet and dry paper. It's even got made in Japan replicated on the heads. These were cast in CO2 core sand, pattern pushed into the sand, wriggled the head pattern around a little, hardened the sand and out came the original head pattern leaving a cavity ready to accept hot metal.

[Michael Moore]

I think we'd probably want to do a proper pattern and add on the fins that were trimmed off for up-pipes. Plus, the foundry personnel wouldn't have to try and expand the mold by wiggling the head but would just ram up and withdraw the pattern as they usually do. I like to reduce the places where error can creep in, since Mr. Murphy can mess with even a perfect set up. And if Mr. Murphy isn't around I can sometimes manage to screw up without his help.

I've attached a photo of the underside of the head. It would be good to have the gasket surface larger so one casting could have enough material to fit different engines with some small variation in stud spacing. That could be done with the underside fins and a larger center boss which I guess might mean a two-part pattern, or the bottom could be made thick and flat and the short fins could be milled in when the combustion chamber was cut.

Would having a thick section like that across the head cause problems? I've read that ideally cross-sections should be kept as even as possible. Would that thick version need to be scaled up a little more because it would be more prone to shrinking than one with a small chamber boss?

I'd also appreciate advice on what shrink allowances to use for things like this head, and if different, crankcases like the YZ in the video. Material would be A356, comparable to LM25 or your 601 (I think that is the correct designation). 8-12% seem pretty common and I suppose it wouldn't hurt to make the pattern to the larger end of the range on a cylinder head that isn't as critical on the final dimensions as a crankcase would be. 4% difference on a 12" long crankcase seems like it would make for patterns that were significantly different in size.

On the heads you did was the sprue gated into the thick pad at the mold split in one place or would several gates be better? What about risers - one right in the middle of the chamber area or several? Would the gating be different if the underside fins were cast in so there wasn't a thick section near the edges? I'm wondering if the Webco head had a gate coming into the side where you can see the thick polished section in the side view photo.

You can see that the OEM Yamaha MX175 head had a big pad next to the gasket surface which I'm thinking might have been used for a riser though they probably have much more freedom on the feed system in a die casting.

I know that the carbide table saws can cut aluminum (with great noise) but I think that by the time I had them modified for a corner or full radius I'd be better off getting a large OD side cutter of an appropriate thickness off of eBay and then have the radii added if I was only able to find a square-tooth cutter. The square tooth side cutters are not uncommon even in 8" diameter which should allow a 3" deep cut. I'd want a good radius at the base of the fins.

cheers,
Michael

[Flettner]

Generally speaking, thinner sections to the bottom and thicker sections to the top with the riser running out of the thickest part. As the part cools there is a "freeze line" running up the component, as each part below freezes off it draws molten metal in from above. Finally the freeze line runs up the riser ( sometimes called the feeder ). All shrinkage should end up in the riser. Yes, my feeder ran off the thickest section, the soild combustion chamber. Runner ( inlet ) ran off the side of the head at the part line, usually quite thin.

[Michael Moore]

Thanks for the info. Deep thin fins look hard to keep from having flaws, but maybe it isn't such a problematic area. My mental impression of the molten metal is like a weld or brazing puddle since that is what I'm familiar with, but the videos show something that is much more fluid than that. I guess if the molten aluminum can run like water and not warm treacle then it has a good chance of completely filling the fins before they start to solidify. And since aluminum is heavier than water it may help it to push all the way to the bottom/tip of the fin quickly.

I haven't gone back to watch the videos again, but I think on the YZ case your pattern incorporated the gates which seems like a good idea to help avoid bits of loose sand from cutting the gates with a spoon.

I've got a number of books on casting and pattern making but it sounds like designing the gates and risers is not always something that can be "cookbooked" with an assurance of a perfect part the first time.

Interesting stuff!

cheers,
Michael