Product review for the Rockin H MA18 grain body kit

Wanting the best for Rockin H customers I seek out evaluations on products and ask for honest feedback about the quality, fit and finish. I had been receiving coaching on the 71 GMC/Chevy project from a custom builder, Tony Dixon, who not only knows that year of truck but has spent much time repairing and rebuilding the real trucks. His knowledge was valuable.

I asked Tony to give an evaluation of the Rockin H 3D printed 71 cab and interior plus an MA18 bed kit. Full disclosure, I gave Tony the cab and bed kit a $100 value with the request to be honest and to do with the parts as he saw fit in exchange for pics and a write up. In phone a conversation I deliberately told him nothing about the parts so his opinion would not be biased except for what he may have read online. This is the first in a series of evaluations that include this bed and associated parts plus the 71 GMC/Chevy cab.

Below is Tony’s unedited evaluation. This will help Rockin H customers buy with confidence.

My initial response to the kit is that it is a beautiful kit containing 1 dump box, a tailgate and a silage rack for the box and tailgate. Although i do not plan on using the silage rack it was a nice option to have. the finish of the pieces lends itself well to primer and the detail is outstanding.

Upon further inspection and removing the components from their sprues with a pair of micro side cutters and a X-acto knife. (see below for pics and captions) I found the tailgate to be printed to one of the front hoist mounts on the bottom of the bed, I carefully cut the tailgate free using a X-acto knife and trimmed the remainder of the pivot that was still connected to the tailgate off. After separating the component parts I carefully trimmed and sanded the sprue marks away using a flat micro file. To further pre-paint prep I drilled the holes in the body sides, front hoist mount, and rear pivot mount with a 1/16″ drill bit to true the holes, I also inserted and glued 2 1/8″ long pieces of 1/16″diameter styrene rod into the holes for the tailgate to mount to the body using Testors liquid cement for plastic models, with the bulk of the rod toward the inside of the body. Once the glue had dried I carefully test fit the tailgate on the pins and filed the outside end of the pins to match the couture of the body. Using a small piece of scrap styrene I had on hand I was able to replace the part of the front hoist mount that was removed with the tailgate and shaped it accordingly.

For final paint prep before priming I used my normal procedure of wiping the areas to be primed and painted with a Q-tip dipped in rubbing alcohol or acetone (i used Acetone in this instance) and let air dry for a few minutes. Once dry I proceeded to prime the component parts with Duplicolor sandable primer which rendered outstanding results.

In conclusion this kit would be a great addition to any collection or farm display and I would not be afraid to recommend it to even the moderately skilled modeler who has the patience to build it.

On a scale from 1 to 10 (1 being the lowest)
Durability 8 (there are a couple pieces that could easily break during removal from the sprews)
Ease of assembly 8/9
Appearance 9
Detail 9/10
Overall 10

On a side note the finished product closely resembles a Mid American Trucks 18′ “combo” bed, a Brehmer 18′ aluminum silage bed, and a SWS 18′ steel silage bed among others from my research. Granted there are probably other manufacturers out there producing this style bed these are just 3 examples I found.

Parts cut away from sprue Parts dry fit Tailgate attached to sprue
IMG_20140312_193329_919 IMG_20140312_192440_696
Repaired hoist pivot point Pins to attach the endgate Gate and body primed
IMG_20140312_194041_971 IMG_20140312_195951_052 IMG_20140312_200138_850
Primed end gate Primed body Showing silage racks with sprue




  1. Tony on April 4, 2014 at 11:40 pm

    Thanks again for the oppertunity