The Bucket Foundry

[oxracer]

Oxyracer, good links there, thanx. Might try the investment recipe using the fibreglass as a reinforcement.

I bought a bag of SRS stuff designed specifically for the block casting method, my intention was to vacuum cast it in the same way that jewellery makers do but on a larger scale.

https://specialplasters.co.uk/foundr...nvestment.html

[jt-87]

Here is my first ever casting: https://youtu.be/o47dTbucaNo
I have modelled(fusion 360) and machined it by myself but aluminium pour was made by local casting factory. Next cylinder I'm going to create all by myself. My intension is to make these small series and sell them. I'm already selling pipes so this is natural next step!
Oh, and here is video showing cylinders performance a bit better: https://youtu.be/oINAXzxXRSs
On first video, Christmas was coming and I just had to make it to run. There were couple of holes in casting and only two bolts out of six were holding cylinder down. On this second video, it runs lean(choke is on all the time) and it already seized ones before shooting the video. It also tends to leak a bit under the head and as you can see, there is quite slippery so this was basically only me having a little bit fun before 2019

Next cylinder is already being modelled and with it, I'm going to make better "how to" videos.



Edit. Cylinder is bolt on for Suzuki PV50 / DS50 / GT50 / OR50 / RM50 / TS50 / ZR50 and with little tweaks for 3d-model it will fit to RM80 1977-1982 and GT80 / TS80. This will not be the most powerfull two stroke on earth but I'm aiming this to be the most powerful bolt on cylinder to models listed above. That means it has to have at least 15 rw-hp on dyno I'm building.

And some info not seen on video: plaster is mixed with sandblasting sand 50/50 and mold was dried about 12h in increasing temperature from 250-370 dergees celsius. Temperature of the mold at the time of the pour was about 100-150 dergees and should have been a bit more. Also risers were badly designed and few first plastermixes ( I mixed plaster about 1 liter batches) were too stiff. Those errors made some extra work.

[husaberg]

Here is my first ever casting: https://youtu.be/o47dTbucaNo
I have modelled(fusion 360) and machined it by myself but aluminium pour was made by local casting factory. Next cylinder I'm going to create all by myself. My intension is to make these small series and sell them. I'm already selling pipes so this is natural next step!
Oh, and here is video showing cylinders performance a bit better: https://youtu.be/oINAXzxXRSs
On first video, Christmas was coming and I just had to make it to run. There were couple of holes in casting and only two bolts out of six were holding cylinder down. On this second video, it runs lean(choke is on all the time) and it already seized ones before shooting the video. It also tends to leak a bit under the head and as you can see, there is quite slippery so this was basically only me having a little bit fun before 2019

Next cylinder is already being modelled and with it, I'm going to make better "how to" videos.

Blood flash work

[Michael Moore]

Here is my first ever casting:

Juha, that makes for a very nice end to the year, and should give you a lot of enthusiasm for future progress in the new year!

Since you are doing investment castings what material/filament are you using for the plug that gets burned out of the investment?

cheers,
Michael

[ken seeber]

Juha,
Excellent work and informative vid.
I'm amazed that there are no (or none that I could see) Z increment contour lines on the fins. Did you use a very fine Z increment or even a mechanical or vapour/liquid polish process. I guess this might be dependent on the filament material you used, as MM has asked.
As you printed it in 2 halves, how did you join them?
Anyways, great stuff.
Thnx.

[Michael Moore]

I hope the filament printers have improved since 2013 (and I suspect they have) when Jeff Henise had a test print done in ABS of a section of Yamaha CT1 cylinder I quickly modeled . I don't think it was meant to be more of a "here's an example" part from the person with a printer, but the surface finish and straight sections that weren't very straight didn't favorably impress us as something that we wanted to use. So Jeff spent 200+ hours making patterns the traditional way for his F37 cylinder.

Speaking of the F37, Jeff will be racing it at Phillip Island in a few weeks. I guess he's going to be made to race in a later (than in AHRMA) 250 class against TD2 Yamahas, so he's fitted a larger carburetor in the hopes of getting a bit more power. He's mainly looking to have a good time and enjoy the races. If you are at the event, watch for him pitted with the Crussells and the other folks from the States.

cheers,
Michael

[jt-87]

Michael:
I couldn't agree more! This was completely perfect first casting and it's 100% certain there will be many more.

ken:
Filament was PLA and printer was Prusa i3 almost straight from box and in too cool room. It made parts to bend a bit. I fixed it by sanding and hot glue. I also bended worst parts by hot air gun but I can't recommend that to anyone, there will be unwanted shape shiftings as well. For future I think I will use soldering iron with temperature control to melt PLA where extra material is needed. Hot glue is faster but it is quite hard to sand to correct dimensions.
Infill was 10% and quality was coarse(or some other fast quality setting). It took about 37h to print both halves.

Parts were joined with PVAC glue and cylinder liner was left in mold. That is very effective way to reduce work hours after casting and it seems to fix enough to casting without any tricks!
In joining I made one mistake: I used play dough to fill some gaps but it turned out that it does not burn out completely and leaves ash in mold. Hot glue and PVAC worked like charm.

[Michael Moore]

Juha, now you need to buy 3 more printers so you can have two cylinders ready to invest every 20 hours. Or two cylinders every 40 hours if you decide you need to go to a slower/higher resolution setting.

I suspect that if you designed a water-cooled cylinder you might be able to print them a lot faster. Fins add a lot of area/complexity to the pattern. Close-spaced and deep fins make machining a pattern a bigger job so I presume they will slow down the printing process too.

How many meters/spools of filament does it take?

Every now and then I go and look at the information on the Formlabs Form2 SLA printer and their resin designed for investment casting. Being able to get a pattern that is very smooth (compared to a filament printer) right off the printer is appealing, but it all gets pretty expensive and I would need to be using it a lot to be able to justify it, especially since I've already got a nice 4 axis CNC milling machine. But printing the patterns would allow some complexity that would be hard to achieve with subtractive machining, and being able to let a printer run at night would be nice compared to having to sit and babysit the mill.

If you have filling issues with the casting you might try adding vacuum or centrifugal force to help fill the mold fully/quickly.

Have you considered printing core boxes and maybe an inverse pattern that you could use to make a positive pattern from a sturdy epoxy (or an aluminum casting) so you could do sand casting? If you want to make a production run sand casting would let you make a lot more molds for a given time investment.

cheers,
Michael

[WilDun]

Michael,
It looks like you have been looking into this process and have done quite a bit of research on the subject. As you more or less say, I would think that casting of finned cylinders using a 3D printer probably takes just as much time (and skill) in the long run as the traditional casting methods! - to wait for the printer to make the (1 time use only) patterns does make this process very slow and most suitable for 'one off' production, but I guess this thread is all about small scale production.

JT
Congratulations - a very good start to 2019 and being able to start off by making a finned cylinder will give you a massive head start!

I am about to try some castings soon - the fact that there is no longer any draught (draft to others) required for pattern withdrawl will be a bonus.
I'm not too clear on just how long it takes to burn out the PLA, - I heard someone, somewhere, suggest that when the mould reaches a dull red is adequate?....... then, what is the best way to ensure that all the ash has been removed? air blast ? vacuum? or both?

I have acquired a very small printer (Malyan 200) - it actually works very well despite it's cantilever design and small size, but I think the best of the cheapies - very suitable for learning the skill without breaking the bank!.

I bought a roll of PLA from Jaycar but it was totally brittle and unuseable so I took it back and they replaced it - no worries!! it probably had been left exposed to our fierce ultra violet rays here in NZ - so keep it covered Kiwis!

I'll be looking forward to learning a lot from you guys this year!

Ken,
Got your printer going?

Happy new year to you all.

[Michael Moore]

WilDun, I find manufacturing technology a very interesting subject and it is easy to spend time thinking about how to make things/make use of new technology. It is much easier to think about it than to then go and make something, but I'm probably not the only one who has that problem, we can't all be like Neil making new engines at the drop of a hat.

I saw some photos on FB of some guys in NL making their own twin-cyinder 2T 50cc race bikes, engines and all, and wow, that is very cool. I've attached a few photos of one of those.

I wish we had bucket racing in the USA, there's not much in the way of a "builder's" class, racing seems to all be about some sort of production bike with limits on what can be changed. The glory days of singles/twins racing seem to be in the past, and there are sure not many 125/250GP bikes showing up at club races any more.

Good luck with your printer, I'm sure you'll have some success once you figure out the secrets of the printing process.

cheers,
Michael

[WilDun]

WilDun, I find manufacturing technology a very interesting subject and it is easy to spend time thinking about how to make things/make use of new technology. It is much easier to think about it than to then go and make something, but I'm probably not the only one who has that problem, we can't all be like Neil making new engines at the drop of a hat.

No, I'm really much the same as you then!, (not Neil!) - hard to do but on the odd occasion, I force myself to actually do it - Neil is something else, a rarity and is internally driven! - I, (like a lot of people) need a swift kick from behind to get me moving!

The glory days of singles/twins racing seem to be in the past, and there are sure not many 125/250GP bikes showing up at club races any more.

I think they still persevere with those in the UK club races, (and of course Moto 3.) - two strokes seem to have been successfully wiped off the map as far as road bikes or racers are concerned, ie whether we like it or not, or whether it was ever necessary at all! I hope Neil can reverse that - not many others have made their mark in any revival attempt!.

Good luck with your printer, I'm sure you'll have some success once you figure out the secrets of the printing process.

Yes that is really the only quiet clean and safe option for me as I will eventually move (slowly) into a late retirement situation - but i'll just keep going till someone finally takes it off me!
I don't want it for making plastic gimmicks - patterns only, in conjunction with Fusion 360 (or similar) - a different challenge but interesting and I now have an incentive to learn 3D stuff.

[husaberg]

Future

https://www.exxentis.co.uk/porous-al...s/suppressors/


Same as bones on birds
http://en.havel-mf.com/seriesproduct...med-components

unless they stuffed it in tubes?
I have poste bubble metal before but no idea how they can do it with a sealed surface?
Steel and Aluminium

[Michael Moore]

My 750GT Ducati had crankcases of that porous aluminum decades ago.

[husaberg]

My 750GT Ducati had crankcases of that porous aluminum decades ago.

As did my Zetor tractor after they gave up trying to make em thicker to stave off the porosity they hit appon the more practical solution just painted the insides and outsides with some rubberized paint

[Grumph]

Interesting...You'd have to assume that the outer surface is chilled so solidifies first - possibly before the air is introduced.

Sorry Michael - Birmabrite alloys mastered the porous casting well before the Italians. As thousands of british bike owners will attest....