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stangtjk 02-16-2020 02:54 AM

Motorized Rocker Panels
5 Attachment(s)
My blazer is lifted and currently wearing 37s so I was looking at step options and haven't seen anything I was crazy about. I like the stealth power steps that tuck behind the rocker but since its not possible with the blazer rocker boxes I had the crazy idea of turning the outer rocker into a motorized step.

My idea was to cut the lower section of the rocker off just above the door ledge and fabricate a new lower section out of some thicker material for the step. I think there is just enough room between the inner and outer rocker to put some linkages to let the step drop down. Worst case, a shallow pocket would have to be made into the inner rocker.

I'm thinking a miata headlight motor wired up to the courtesy light switch and a crank/rocker 4 bar linkage would eliminate the need for any type of motor controller. The motor and 4 bar linkage would be behind the inner rocker in the rocker box area. Not sure if the motor would be strong enough on its own but could easily put some helper springs somewhere to help take some load off.

I made a rough cad model of the concept. See it in action here >

Any thoughts?

boonedogs72 02-16-2020 12:27 PM

Re: Motorized Rocker Panels
Damn cool idea!

DemkoG 02-17-2020 04:38 PM

Re: Motorized Rocker Panels
Defiantly a cool idea. would they hit a stop or would the motor have to support the weight of the person?

stangtjk 02-17-2020 06:49 PM

Re: Motorized Rocker Panels
As long as no one ever tried to jump on the step while it's in motion the motor should never be supporting the weight of a person. With the step all the way down it would just be hanging by the two big linkages.

stangtjk 02-18-2020 04:10 AM

Re: Motorized Rocker Panels
2 Attachment(s)
Worked on this idea a little more.

I plan on having some 1/8 plate CNC plasma cut for the step structure. I added locating tabs in the design to make fit up and welding easier. To maintain the contour of the outer rocker I was thinking it would be easiest to keep the lower section that gets cut off and reattach it to the step skeleton.

I went ahead and ordered some miata headlight motors to figure out the wiring and judge whether or not they'd be sufficient to raise the step.

I've got access to a manual mill and lathe however I have no machine skills so I tried to keep things simple in that perspective. For the hinge points I'm looking at off the shelf 3/4 stripper bolts and oilite bushings. Only machining work will be drilling, tapping and cutting a couple counter bores.

One part I'm still contemplating is how to pin together the links of the crank/rocker mechanism that will be driven by the motor. My thought was to use some pins/rivets similar to how a hood hinge is put together. I don't want to use nuts/bolts because that would require bends in the links for clearance and I think I'd have a hard time keeping the links the correct length to allow the 4 bar to operate correctly.

Will also need to factor in some kind of adjustment to maintain alignment of the rocker with the step closed. Not expecting a lot of slop but things have a way of moving around over time. Maybe a little adjustable bump stop similar to how the front of a car hood is aligned.

mcmlxix 02-18-2020 08:40 AM

Re: Motorized Rocker Panels

stangtjk 02-18-2020 12:26 PM

Re: Motorized Rocker Panels

Originally Posted by mcmlxix (Post 8680426)

This ain't no jeep.

mcmlxix 02-19-2020 04:34 AM

Re: Motorized Rocker Panels

Originally Posted by stangtjk (Post 8680537)
This ain't no jeep.

Your design looks like the same mechanical architecture as the Rockslide Engineering design as opposed to the AMP Research design...

stangtjk 02-20-2020 12:11 AM

Re: Motorized Rocker Panels
Yeah, very similar. I tried looking for photos of the internals on those but not many images of the inner workings online. My design is a mix of the rock slide engineering steps and the Kodiak steps shown here>

stangtjk 02-20-2020 01:17 AM

Re: Motorized Rocker Panels
1 Attachment(s)
I sketched out a rough outline of the cross sections of the bottom of the door, outer rocker, inner rocker/floor and rocker box to adjust the design to fit. The model of the generic window motor I grabbed off grabcad looks bigger than what a window motor should. Not sure how accurate its dimensions are but I'll compare with the miata motors when they get here.

I originally tried keeping everything but the motor between the inner and outer rocker but it wasn't working out that great as the top of the step would have only been about 1-3/4" wide. So I'll be making a pocket in the inner rocker give room for a wider step. The top of the step in the image below is about 2 3/4" wide but I'll play around a bit more to see what I can gain. Would like to get close to 4" but its looking like 3 1/4" might be the limit without cutting into the rocker box.

More tweaking to do. One advantage to using a pocket is the assembly can be all put together off the truck and mounted all at once. Not exactly a bolt on mod but close as it'll get for being completely hidden.

Ol Blue K20 05-25-2020 01:05 PM

Re: Motorized Rocker Panels
Any updates on this?

IGOR 05-27-2020 11:18 AM

Re: Motorized Rocker Panels
Cool idea!

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