Hot-rodding the Toyota MGR

[Cyruscosmo]

Originally Posted by freebeard

CNC is so 20th century. 3D printing is the future.

That is next on the major tool list. I have all the components and plan on printing parts in PLA and then encasing the plastic parts in ceramic slip and sand layers and then firing the thing to burn out the plastic.

What I have left is a hot ceramic mold that I can then fill with aluminium or iron...

This method is used for making cast parts with internal passages and flanges that can not be machined otherwise.

Yes I could use the traditional sand cores but then I would have to make molds for all the cores as well. With 3D printing I could print all of the "cores" in place in the first go round...

Cyruscosmo

[e*clipse]

Originally Posted by Cyruscosmo

That is next on the major tool list. I have all the components and plan on printing parts in PLA and then encasing the plastic parts in ceramic slip and sand layers and then firing the thing to burn out the plastic.

What I have left is a hot ceramic mold that I can then fill with aluminium or iron...

This method is used for making cast parts with internal passages and flanges that can not be machined otherwise.

Yes I could use the traditional sand cores but then I would have to make molds for all the cores as well. With 3D printing I could print all of the "cores" in place in the first go round...

Cyruscosmo

It would also be a good way to produce a mold for composite parts.

- e*clipse

[Cyruscosmo]

Originally Posted by e*clipse

How do you do that??

Horsepower = (Torque * RPM) / 5252

At 0 RPM, you have 0 HP. That's why all the HP graphs start at 0.

Sorry I was thinking more along the lines of gas vs. electric torque curves starting from zero RPM. The electric motor would get up and go in the lower gear ranges much faster than a gas engine.

Watch the electric cars get off the starting line next to a gas car. They accelerate like they are steam catapult powered.

Remember I am a gear head making the transition to electric.

Cyruscosmo

[freebeard]

Originally Posted by Cyruscosmo

Actually even 201HP would work well with a modified C4.

One would hope. The White Zombie has tandem motors and it's a race between burning rubber and melting cables.

The rear mounts are in plane with the ends of the frame arms. There are two other arms that hold the tops of the shock absorbers. The front motor mount is about 9" above the forward stock transmission mount and points up. A bar that is bent similar to the Toyota bracket and about 29-32" wide would bridge between the shock mounts and pass above the transaxle mount point. I'm concerned about the 9" lever arm if it is only perched atop the front mount

That could all be rigid mounted with Toyota bushings all around.

e*clipse -- Someone with more resources than you or I will figure it out. Maybe it has to do with cryogenic tempering to tweak the grain structure. Certainly, that would be a good precursor step to final machining of the raw part.

Thanks for reposting those links. I should take a look. I'm already concerned about the part supply drying up.

[Astro]

Originally Posted by Cyruscosmo

That is next on the major tool list. I have all the components and plan on printing parts in PLA and then encasing the plastic parts in ceramic slip and sand layers and then firing the thing to burn out the plastic.

We used a similar technique in our secondary school art class to mould pewter. We used wax to create the form of the item. This was placed in a steel cup, then we pored liquid plaster into the cup to surround the wax form. Once the plaster set the whole thing was heated in an oven. The wax ran out. Then we just pored the molten pewter into the void left by the wax. Then the whole thing was immersed in water and the plaster dissolved away leaving the pewter item. Because the plaster was so fine the finished object had all the fine detail of the original wax form.
Certainly the wax was easy to work with and was easy to remove from the mould without leaving residue that affected the final result.
I just checked wiki and plaster moulds are good up to 1200C so aluminium's 660C melting point shouldn't be a problem.
Can 3D printers use wax as the medium rather than plastic?

[Cyruscosmo]

Originally Posted by e*clipse

It would also be a good way to produce a mold for composite parts.

- e*clipse

Pretty much... You could extrude the A and B parts of the epoxy resin into a small heated mixing chamber and print with that. But that will be an experiment for someone else. My next door neighbor laughs at me when I help him lay up carbon fiber or fiber glass. It always gives me such a headache.

He has been working with that stuff since the late 70's when he started building electric cars, boats, trucks, gokarts, barcaloungers... Yes I said barcaloungers. He is an old school builder... "Think The World's Fastest Indian" and you would have a good idea.

Anyway I got the EV bug from him but I tend towards the new fangled tools...

Cyruscosmo

[Cyruscosmo]

Originally Posted by Astro

We used a similar technique in our secondary school art class to mould pewter. We used wax to create the form of the item. This was placed in a steel cup, then we pored liquid plaster into the cup to surround the wax form. Once the plaster set the whole thing was heated in an oven. The wax ran out. Then we just pored the molten pewter into the void left by the wax. Then the whole thing was immersed in water and the plaster dissolved away leaving the pewter item. Because the plaster was so fine the finished object had all the fine detail of the original wax form.
Certainly the wax was easy to work with and was easy to remove from the mould without leaving residue that affected the final result.
I just checked wiki and plaster moulds are good up to 1200C so aluminium's 660C melting point shouldn't be a problem.
Can 3D printers use wax as the medium rather than plastic?

Oh hell yeah! The process for printing wax is a bit more fiddly though. You have to deal with hot wax and cooling times, the balance needs to be spot on.

The usual method for wax is an inkjet type arrangement. Trying to "extrude" hot wax would be a royal *&$%^!

Here is a vid that covers a lot of 3D printing processes at 6:06 they show one of the wax type printers. Those things can print some very very fine detail!

https://www.youtube.com/watch?v=5voxz39QjcQ

I have actually tried to use plaster and found that it tends to fall apart to easily which is the reason for going with ceramic. It is a bit labor entensive but it can capture very very fine detail as well. This vid shows the process I am going to use but instead of a wax part it will be a 3D printed part in PLA plastic. PLA is a plant based plastic and burns out of the mold with very little residue. The narrator is a bit odd, either it is a computer generated voice or this guy is just 2D.

https://www.youtube.com/watch?v=HcOJ...eature=related

Cyruscosmo

[freebeard]

So I see there was a whole another page of comments. I mentioned 3D printing for the humor, but it sounds like you are right there. I just got a drill press. And torque is what moves you off the line.

Printing will be available as a service in a variety of techniques like laser sintering. And Local Motors is doing interesting things with ABS/Kevlar.

[Cyruscosmo]

Originally Posted by e*clipse

Ok here's some real info (not just my fuzzy memory)

The papers below go into amazing detail and will require many cups of coffee to help with the short-circuiting brain .... They go into testing stuff that no other testing organization gets remotely close to.

The main thing that is important here is that Toyota made a major improvement in motor technology around 2005. Most of their new hybrids use this technology; this is why I say the controller for all of them can be very similar. The paper about the development of this technology is here:
http://e-mobile.ch/pdf/2005/321.pdf

Here's the ORNL paper about the 2010 Prius:
http://info.ornl.gov/sites/publicati...s/Pub26762.pdf

For your project, it actually seems like the system Toyota developed for the Lexus 600h sedans and the Camry would be a good starting point:
SciTech Connect: Evaluation of the 2008 Lexus LS 600H Hybrid Synergy Drive System

There are others, detailing the 2004, 2007, Camry, etc. available from these links.

I know some folks w/ CNC's. It may take some interesting trades, but I may be able to get some time...

I do have solids modeling software, and CNC code generating software (and know how to use it). I do have a Bridgeport mill w/ a DRO and a Clausing lathe. I could get accurate bearing locations with the DRO. It would require some clever design, because machining it from a solid chunk would require a LOT of $$$.

Oh, regarding output splines, etc: The local driveline shop is extremely good and he just got a CNC and broaching equipment. A custom spool or output shaft is no problem here. I'll check his prices today.

- e*clipse

WoW!!! so much math... That was an enjoyable read though, Thank You E*clips! I will leave the math to the powers that be. I am interested in that transmission setup. Can the generator rotor be used as a motor as well?

It would require some clever design, because machining it from a solid chunk would require a LOT of $$$.

That's why I was leaning towards the 3D printing of a case instead of trying to machine it from billet. Splines would have to be made so your contact would come in handy.

I do have a Bridgeport mill w/ a DRO and a Clausing lathe. I could get accurate bearing locations with the DRO.

GAH... you lucky dog. I am working on the mill part. Got a nice lathe already.

I have about 2000 pounds of cast aluminum pieces waiting. I have all the parts for a furnace to melt it and a kiln to process the investment castings. All I need is 48 hours in a day and I may have all this done in a few years! Well not that long but ya know what I mean, life keeps getting in the way of my fun plans...

Cyruscosmo

[freebeard]

So, PLA to ceramic to metal inhouse, then off to NorCal for the touchup machining?

What do you plan to make with a ton of aluminum?