Monday, 20 May 2013

3D Printing parts for the 10KW charger build

After spending a brief lunch break over at the mechanics last week I roughed out a box in cardboard to give me an accurate idea of how much space I have in the micro boot on the Honda Beat to fit the charger into, I will be using the right hand half of the mini boot space for the charger, this will give me simple access to the charger (for charging) accessed via the boot which should be ideal for charging, I also hope to put a “Standard” (there are several standards by the look of it) socket for connecting the power to charge into the ex-fuel filler cap.
The left hand half of the mini boot space will hold the Soliton, by coincidence there is an access plate from the mini boot into the main “Engine” area of the car this access plate is exactly the right size to hold the Soliton, Brent was considering mounting the Soliton directly on this plate which is cool as it would make removal of the Soliton easy if necessary.

I am also thinking this is a good plan, so once I got the box home and considered how I might make (fold) a box out of 3mm Ali, I moved onto roughing out the part placement for the charger.

It looks like it will be fairly straight forward, I am intending to mount the very large single capacitor onto the rightmost wall of the charger box using 3D printed brackets which I constructed in 3D using OpenSCAD, after making a simple hoop strap with mounting bar and holes (photo coming soon) and printing it I then decided to modify the second strap into a cap for the “Dangerous” connection end of the very large capacitor, this will protect the bare connections from accidental shorting if anything comes lose in the charger box whilst driving, I also intend to mount this large capacitor connection end down also for safety sake (although this is not absolutely necessary if I am going to “cap” the Capacitors connection end, so this could change)

Very large capacitor with 3D printed bracket & bracket-cap

I have also been thinking how I will mount the toroid transformer (also very large) it needs to be close but not touching the heat sink and the air flow needs to be unrestricted by any mounting solution, the instructions with the charger build suggest using a sheet of thick HDPE and cutting “C” brackets from this, this is a no brainer for 3D printing as I could print HDPE if I needed to although ABS should be fine as there is little difference in heat tolerance of these 2 thermoplastics.

I will fabricate a CAD toroid mount bracket which has fins that slide between the veins of the heat sink with a ring the same size as the toroid fixed to these fins I can then mount 2 (or 3) “C” brackets that are joined to the ring and hold the toroid from moving anywhere, this should give me a firm mount with plenty of heat dissipation capability.

Toroidal 3D printed bracket on printer with support 
Toroidal 3D printed bracket support removed

This does meant that my charger component placement will be a little unusual but this is a consequence of the size of the box I have to fit this into and the need for serious cooling when the car is charging.

Brent tells me he can drill out the old battery plate that sits in the bottom of the mini boot where the old 12V car battery used to be located, this will give me a few extra mm of height which is going to be required to get it all in if I want a lid for the charger, which I will as the charger controls will be mounted on the lid.

But all in all it looks like it will all fit quite nicely.

Lots more photos coming as soon as I figure out why my canon camera has suddenly refused to be recognized by my PC!

Thursday, 16 May 2013

Battery Box discussions

Spoke to Brent last night on what he had discussed with Steve about the battery box placement and sizes/costs etc.

It looks like it is going to work out quite nicely, it seems I will have 3 battery boxes, 1 each side of the forward motor mount, and a third in the front bonnet underneath the spare wheel (should be able to retain the spare wheel and tray in the flip forward style bonnet)

He also said that he had mocked up the boxes and sent the details to the box fabricators (TIG weld specialists) and that they were getting back to him with prices, he also thought that they would not be happy to use the old “Dirty” Ali that I have and that they would probably want to use new Ali to avoid any extra time being wasted cleaning the Ali before welding.

Ho Hum, it seems that welders just like builders don't like to reuse and recycle! Oh well it is more important to me now to just get the boxes made pronto as I am desperate to not have the build stall for any reason, so I will probably just go with the welders Brent uses depending on cost. 

Brent was concerned about me supplying the charger for sizing purposes as he need to know if there is any more cutting of the boot required before they begin jet washing the underneath and wire brushing ready for under sealing (I have specifically requested this as I need the car to last 10 years to be economically viable)

I have told (guaranteed) Brent that I could make the charger fit the right hand side of the “mini” boot without the need to cut anything, I am going to pop over to the mechanics this lunchtime to mock up a box in cardboard so I can be sure I can fit the space available, I also need to make sure that I can cool the charger effectively, I will discuss options for this with Brent, there is a convenient fan sized hole right where the charger will go that I hope to use for air cooling with a fan/s.

Brent also mentioned the need for a transformer to convert the output from the Soliton JR to 12V (it does not supply this) Brent thought that I should already know about this (I do remember a brief discussion with Steve on this but was not aware of extra parts required, I will check this with Steve).

Motor & Gearbox fitted

I visited the Mechanics last Friday 10th May to take a look at the Motor and Gearbox fitted (temporarily), took lots of photos

Series of Photos showing motor fitted (temporarily)
with custom steel mounting brackets courtesy of SMD (Brent & Luke)
The green MG is underneath the Honda which is up on the lift.

Brent had made up some custom steel motor mounts also fitted and discussed the need to get the batteries over for sizing up the battery trays, along with the rest of the bits.

We will be removing everything and cleaning the (very dirty) car inside and out before prepping, rust protecting, (although there is very little rust considering this is a 20 year old car!) and under sealing.

If I am not bankrupt by the time I have finished this build I would also love to get just the outside prepped and re-sprayed in metallic black ready for some decals or maybe a whole car wrap graphic (sweet).
I immediately mailed Steve from Jozztek asking for some batteries for sizing purposes and updating him on the swift progress recently.

I dug out the 2 sheets of 3mm Aluminum this weekend, they turned out to be 6x4 (foot) sheets rather than 8 x 4 as I had remembered  but there should be enough for the boxes.

Steve has just mailed me to say he will be catching up with Brent tomorrow (Tuesday 14th) to give him the batteries (for box sizing) and to discuss details mounting positions etc.

I must now get busy with the charger build.

Friday, 3 May 2013

Coupling plate & splined “low inertial” coupling made & fitted

Called Brent yesterday to check on progress and discovered that he has received the motor/gearbox back from the CADCAM engineer as of Thursday 2nd May.

We (Brent) decided that it would be simpler for the CADCAM engineer who was tasked with milling the coupling plate & splined collar to supply the motor & gearbox coupled, avoiding potential mistakes in manufacture or fitting of the plate & collar.

Brent tells me that he is collecting the Honda from me next Tuesday for fitting of the motor /gearbox into the Honda Beat.

Then we should be ready for Steve (Jozztek) to take a close look at where best to position the controller pack (Soliton Jr)  the Charger & Battery Boxes/Trays, my friend  who was going to do the TIG welding has now gotten held up on other business so it looks like I will have to find another TIG welder (person) but all in all things are really starting to move forward on the build now, I am still hoping I may get to drive this beauty before summer is over, after all it is a convertible.

I will try and visit the mechanics tonight to get some photos of the Motor/Gearbox before it is fitted.