Fitting Pintopower's no-need-for-a-3rd-shock-mod transmission retainer

[XV Pilot 1937]

This morning I received an exciting package with a Shapeways logo on it:

Inside were a pair of Pintopower's no-need-for-a-3rd-shock-mod thingies. Here is one prior to fitting:

First order of business is to clean out the mounting holes with a drillbit:

How big you drill the holes depends on your choice of mounting hardware. I found these in my bits box:

They were the right length, and the wide, flat heads meant minimal intrusion into the battery bay.

In preparation for installing the retainer on my runner Hornet, I had removed the gearbox:

It was then a simple matter of holding the retainer in place and using its holes to guide the drillbit when drilling the chassis tub:

The screws are then put in place, passing through the tub and into the retainer:

This version allows the use of the stock battery door:

One can then reinstall the gearbox:

The retainer fits perfectly and is very neat and unobtrusive:

In practice it works just like the central peg on the DT-01, allowing full articulation of the rear suspension while keeping the midpoint of the gearbox leading edge from moving up and down, thus avoiding the annoying "click" on acceleration and braking.

An excellent piece of design which I can thoroughly recommend!

[Shodog 1847]

I haven't been paying attention but I would assume this would work on a lunchbox/midnight pumpkin chassis?

[mongoose1983 3362]

What a fantastic piece. Totally genius!

[Nitomor 2122]

Please let us know how you get on with it after a few packs. I wonder if riveting it on would be effective, my Lipo is a very tight fit in there, I fear the protrusion of those screws although minimal would nevertheless rub and wear into the lipo!

[taliesin 262]

Aluminum rivets of the proper length should work without breaking the plastic or stressing it too much. Steel or too short of rivets would probably stress it though.

[Pintopower 1499]

How did you get it so fast!? You just ordered that. I must say I was terrified when I saw your thread, I mean even though I overly test my stuff I am always worried that some anomalous issue will occur on someones car any my part will explode taking an entire city block with it. The DT-01 was the inspiration once I realized how close my battery door mod was to the tranny. Keep me posted of any issues you may come across. It takes a couple of packs to break it in a bit more.

Oh and I hope you dont mind me responding to a couple of replies:

I haven't been paying attention but I would assume this would work on a lunchbox/midnight pumpkin chassis?

I don't think so. The trans on a MP is farther away. I have been planning to make that mod though since the slappy tranny is by far the worst on those chassis.

What a fantastic piece. Totally genius!

Thank you!

Please let us know how you get on with it after a few packs. I wonder if riveting it on would be effective, my Lipo is a very tight fit in there, I fear the protrusion of those screws although minimal would nevertheless rub and wear into the lipo!

I have used mine for around 20 or so packs before I put them up for sale. I was worried about friction but everything seems to be fine. I am surprised to hear your LIPO's are that long. My full size soft packs are around 6mm shorter than a NIMH. I also use tiny lipos so my battery compartment is lined with foam on the car I have at the office. I too worry about wear so I use a lot of thin adhesive backed foam on all my cars to prevent batteries moving about.

Aluminum rivets of the proper length should work without breaking the plastic or stressing it too much. Steel or too short of rivets would probably stress it though.

Maybe if they are alu/alu but i think they would still overstress the retainer. It is a good idea since they heads are shorter. I really didn't want the heads in the battery area but that was by far the simplest solution.

[kontemax 1794]

I believe yes. Rear gearbox is the same.

Max

I haven't been paying attention but I would assume this would work on a lunchbox/midnight pumpkin chassis?

[mongoose1983 3362]

I believe yes. Rear gearbox is the same.

Max

Gearbox might be the same, but there is a huge gap Pintopower between the gearbox and the chassis so Pintopower's piece can't touch it.

Might need to be reworked in the future to work on the LB/MP.

[XV Pilot 1937]

I wonder if riveting it on would be effective, my Lipo is a very tight fit in there, I fear the protrusion of those screws although minimal would nevertheless rub and wear into the lipo!

How about countersinking the chassis tub holes and using the short 3mm screws from the underside of a TT-01? This should give no intrusion whatsoever.

[XV Pilot 1937]

I haven't been paying attention but I would assume this would work on a lunchbox/midnight pumpkin chassis?

This version wouldn't, but I'm hoping it's success on the Hornet will motivate Mr Pintopower to create equivalent pieces for other clicky Tamiyas such as the Lunchbox, Rising Fighter, etc.

[Pintopower 1499]

This version wouldn't, but I'm hoping it's success on the Hornet will motivate Mr Pintopower to create equivalent pieces for other clicky Tamiyas such as the Lunchbox, Rising Fighter, etc.

I will do the MP but I forgot how horrid the Super Hornet is. Uhg. Yeah one day...I am working on my SH and RF so I think It will be sooner than later. Me thinks MP body mounts first. Those should take all of 10 min.

[taliesin 262]

I didn't think about the stress factor on the 3-D printed part, I was just imagining the stress on the chassis! Derr.

I wonder how the 3-D material would tolerate the sudden "snap" of the rivet setting? Might be a good experiment to make with some test pieces.... Surely there is less stress with a hand set screw than the rivet.

Counter sinking is a thought, but there isn't much material there and many of the counter sink bits are too steep of a conical point for very thin material. I tried to countersink the heads of rivets in .040 aluminum and it was not a great result - the material got too thin and the center opening too sloppy so I eventually gave it up as a bad job and dealt with the rivet heads protruding.

[kontemax 1794]

This is bad, I have both models but they are both nib, sorry.

Max

Gearbox might be the same, but there is a huge gap Pintopower between the gearbox and the chassis so Pintopower's piece can't touch it.

Might need to be reworked in the future to work on the LB/MP.

[mongoose1983 3362]

This is bad, I have both models but they are both nib, sorry.

Max

I'd say build them Max, that way you can have both ready for the time Pintopower's have the solution ready to order

Oh, and obviously, pictures of the building process would be fantastic

[Pintopower 1499]

I'd say build them Max, that way you can have both ready for the time Pintopower's have the solution ready to order

Oh, and obviously, pictures of the building process would be fantastic

I have 2 CW01's on my shelf. I will need to look at them. I know the gap is huge.

[mongoose1983 3362]

I have 2 CW01's on my shelf. I will need to look at them. I know the gap is huge.

That would be great, Alberto!

[Wooders28 5137]

That looks like a factory hop up,excellent job!

Does it effect handling (more bouncy bouncy than normal) in anyway, presumably you loose what little independent suspension you have on the live axle?

[shenlonco 1187]

just curious is the attachment holding the gearbox in the up position?

If it does this is in the position that makes the suspension harder to compress when driving the suspension works better with the front of the gearbox held in the down position of the side pivot slots.

[kontemax 1794]

I would like but I have no time, no space and no money to build them at the moment.

Max

I'd say build them Max, that way you can have both ready for the time Pintopower's have the solution ready to order

Oh, and obviously, pictures of the building process would be fantastic

[Flat_Out 57]

Ah but there's something cool about running 5 you-g's. Haha

[GregM 1113]

just curious is the attachment holding the gearbox in the up position?

If it does this is in the position that makes the suspension harder to compress when driving the suspension works better with the front of the gearbox held in the down position of the side pivot slots.

It holds the gearbox in a middle position. So the retainer acts as a central pivot, still allowing movement in the side slots. If you've ever build a DT-01, you'll understand the advantages over a regular Hornet setup.

So the live axle gearbox is still allowed to roll and compress, but will be less negatively affected from quick acceleration/braking.

[XV Pilot 1937]

That looks like a factory hop up,excellent job!

Does it effect handling (more bouncy bouncy than normal) in anyway, presumably you loose what little independent suspension you have on the live axle?

I haven't been able to get out and do any significant testing yet, but initial impressions from street and garden running show a reduction in bounciness, which makes sense since without the mod there is no damping to the front gearbox movement, but with the mod any movement of the gearbox is controlled by the oil dampers.

[shenlonco 1187]

It holds the gearbox in a middle position. So the retainer acts as a central pivot, still allowing movement in the side slots. If you've ever build a DT-01, you'll understand the advantages over a regular Hornet setup.

So the live axle gearbox is still allowed to roll and compress, but will be less negatively affected from quick acceleration/braking.

I built a few of the hopper type chassis.... then that answers my ? It is best to hold down the front of the gearbox at the bottom with just a little play so it still fully twists side to side... the higher the gearbox front goes up the worse the rear suspension works and gets harder to compress the rear shocks down.

would have been nice if the part was made to hold the gearbox down in the front as far as it can.

[mr crispy 2297]

That's a nice neat solution. Can you post up a link to the shapeways page? Knowing the material they use for printing it'll be more than enough for the job! 😉

[XV Pilot 1937]

Here we go:

http://www.shapeways.com/product/RHD88KMMX/hornet-transmission-retainer-with-no-trans-tab?li=shareProduct

Pintopower also has other Hornet upgrades available from Shapeways. Here is a link to his thread on the subject:

http://www.tamiyaclub.com/forum/index.php?showtopic=79012