The original plunge router was made by blokkendoos, and I loved it. But I needed to route precise slots into boxes, and his router lacked a bushing. I also needed the guide plate to never, ever move. The original guide plate bolt moved around a lot when I was trying to route straight lines because the bolt was not secure. It needed to be locked down like it was, well, bolted down.
I used Fusion 360 to add a bushing, a second height adjustment bolt, and bolt holders on the bottom plate which hold the height adjustment bolts down. I used it to route exactly perfect holes into a box, as if I had a real plunge router! Only I was using a Dremel tool.
2x 4 inch 1/4-20 bolts, partially threaded so the guide plate can move freely up/down.
2x 2 inch 1/4-20 bolts, fully threaded for height adjustment.
6x 1/4-20 nuts, 2 for each height adjustment bolt, 2 for the bottom plate.
4x 1/4-20 sleeves, 2 for the guide plate and 2 for the bottom plate. May need to use a rat tail file to allow the sleeves to fit. But once they do, those bolts are NOT wiggling around anywhere.
2x M3x30mm as handles for the guide plate.
2x M3 nuts for the handle bolts on the guide plate
2x M2.5 very short machine screws for the bolt holder lids.
Yes, I mixed imperial and metric bolts. No tears in the space/time continuum yet.
Bushing is a 20mm diameter, 9mm tall.
Enjoy! And thanks again to blokkendoos for the original model.