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Hi Lee,

Let's say I rediscover CAD tools. Back in last century (should say last millenium, really :-D), I was student in Industrial Engineering. I did use some CAD softwares, but they were clearly not as user friendly as the one we are having today. In my studies I had probably about 60 hours of work on those tools (early nineties). Software were slow, rendering inexistant, and to do it correctly, you had to be able to do it on paper first (which I was very good and very fast at). Plus, at that time, there was no real application of having it in CAD for small projects, except to learn about it. It was eventually interesting for big project when you can save prototyping using CAD to check parts assembly...

Basically, I went back to CAD in the last few weeks, and in two hours starting from scratch with no training, I probably did more complexity than when I was student 30 years back.

I did try Fusion360, Tinkercad and Freecad. Fusion360 seems the more powerful of those.  There is some tutorials on youtube for each of them, but I did not really look into them: I'm not able to keep looking at a tutorial, I prefer from far playing with the things by myself...
The more complex in what I did today was to find the right way to take the measurements. It is always a question of using the right reference point. And it may be easier in some cases than others : symmetry helps, but not everything is symmetrical... I'm curious to see if I'm able to reproduce a Hunter chassis in CAD for example (it might be easier to start from scratch than to try reproduce something)...

Fantastic Silvertriple, I did pass my exams in technical drawing but never used it in my career. CAD side of things I have never used anything and onlr recently looked at it. Tinkercad first which I was able to design a hard to find plastic part for my 1978 Honda. I don't think it was done correctly but it looked ok. I will have to try and find the stl on my computer and see if I can slice and print it. 360 is great, I can't wait to do the designing of rc parts myself. Looking forward to seeing your designs. 

Went a bit further on the shock tower reinforcement to build a prototype for an repair attempt for broken shock tower.It will help me to define the solution, as I need to check multiple things. I have a idea in mind, but will have to verify it is feasible. In the meantime, this part can be use to reinforce non broken shock towers. It was tested yesterday night, and did not have the time to post about this earlier... I tested it on the 3 proper chassis I have and it fits in all the case...Material is currently PLA. But I intend to print this either in PETG or ABS (PETG is probably easier to print).Next step is to design the lower parts... I still need to think about this, and it may require a modification of the part you see on the pictures, as I may need to complete the inside of the shock towers, at least partially. That said, measures are proper, so I believe i'm in the good direction...

A pretty nice reinforcement piece

Another NIP part arrived today


I had some hope that TGB was back in business on June 1st, but they are not yet back on ebay. Next date is 30th of June. I know they do reproduction of the Marui Hunter body, and I would need a least 2 or 3, and a wing....

In the meantime, it smells well for a chassis rebuild within one of the next evenings/week-end, except I still need to clean the parts.

I also have other things to do. I plan to print 3 of the single sided shock tower brace in black PETG (got the filament today), and 1 set of rear tires... For the front tires, they are not on Thingiverse, I'll have to model them myself...
 

Finally printed the shock tower braces  in PETG. The finish is nice, and the final product seems good in terms of properties (flexion like ABS, but strong in the long direction). I have printed an extended version as there is one of the chassis where the screw was torqued too much apparently, so this is to be on the safe side.


Also launched a print for 2 tire set and sleeves as found on thingiverse in TPU. Interest one: it will save the nice and new tires for the shelve, and the second interest is it will allow me to check how much this is a good solution for running a Hunter. I will need to model front tires (as the guy who published it on Thingiverse did not). The print will be fairly long : more than 24 hours, so results will be visible only within next days.

Next step for the afternoon :
- cleaning reinforced nylon parts and metallic parts
- group the parts per build to be able to take a full stock take of what is remaining missing
- model roll bar and rear bumper

Let's see if I can put some pictures later on today...

State of the stock after reinforced nylon cleaning. I do have whatever is required to rebuilt 3 Hunters (minus some exceptions).

• Grey chassis. Will be completed with all new parts, and the only exception to the original will be the color of the gear covers and radio box which are coming from a Galaxy cluster. It is complete, including pilot, roll bar and bumper.
• Black chassis. Will be complete with some new parts (coming from the remains of the clusters) and parts in very good shape. Black gear box covers are having a white fog due to a reaction with the cleaning agent . Radio box is coming from Shapeways. Missing : pilot, roll bar and bumper.
• Black chassis with holes at the rear end, probably to mount an alternative bumper. We'll use the rest of the parts, but for reinforced nylon parts I'm now sure I have what is needed. Gear box covers are coming from Shapeways. missing pilot, radio box, roll bar and bumper. I will have to improvise a motor mount, probably using PETG print.

on the metal part side, I'll be probably missing 2 spacers for one of the lower wishbones of the front train on the third one, and one headless screw used to fix the shafts in the transmission. I've not cleaned them yet, but will have to do this. INext steps is likely to be in some time as next week-end is full of activities already.

Print results before removing all support


First, this is encouraging, there is a lot of wrong things in my first print of tires (stl found on Thingiverse):
- wall were not setup right, I believe this did not helped to get it right. I will make the walls thicker.
- temperature probably too high, as there is a lot of oozing on the print, which did not help to make it right
- layer was too thick. Need to do it thinner.

That being said, the tire is flexible. It won't be as sticky as a rubber tire, but that should do it for some type of surfaces... As matter of fact, as there is not enough layer, it does not keep well together, and it was not possible to remove the inside support. That being said, I can mount them on wheels this way... I did not tried to run, as there is too many imperfections on this tire set. I'll need to work out in the slicer for different and better parameters... 

Tapping screws topic again
I had a doubt, so I order what was needed to measure the step of the screws...

Marui tapping screws are :
- diameter 4, step 1.5 mm. For information the Plastite screws I could find on Bricovis have a step of 1.75 mm for the diameter 4
- diameter 3, step 1.25 mm. The Plastite screws from Bricovis have the same step for a diameter of 3 (this is perfect match).

For the machined thread screws, they are all Metric, with the proper step for the diameter, as per the norm (M3 - 0.5, M2 - 0.45).

I measured as well the body mount, as I will need at least 2, because I have only one. A friend propose to turn them, so I had to measure the step. It's a diameter of 4 but with a step of 0.8 (basically what you would find on a metric screw of 5 in terms of step, 4 si supposed to be 0.7)

For the tapping screws in diameter 4, I have 2 options
- Find the good screws
- fill in with resin, drill and use Plastite screws

In short, if you know where to find tapping screws of 4*12 with a step of 1.5mm, please tell me :-D
 

I did think about something like this, but Optimaforever made it, and it is so much better than what I thought about...

www.facebook.co...maforever/ ... 2760819205
It seems that soon, we will have solution to revive our Marui Hunters and Galaxys...