Mounting bodies - how to help would be appreciated

[black3sr]

[HomeRacingWorld]

[black3sr]

[mattb]

While I only do 1/25 scale, the mounting process is about the same as 1/32, just a little more room to work with. I have used lots of techniques but there are two I use most. There are lots of pictures here, so I will do two threads.

This picture shows the plastic I use most. The tubing is Plastruct or similiar and the small 3/16 slides inside the bigger 1/4 inch size.
The other piece is a resin piece I make. I use the resin piece to mount full 1/25 scale bodies and will cove that method in this post.
The 2 free standing post mounts are one style I have used. P1010033.JPG
This is how the plastic piece fits the chassis, H&R frame here but could be extended Womp, or any kind of flat brass like I build. I mount this to the frame first. I mount with holes the same diameter as the screws.
P1010034.JPG
P1010035.JPG

After this is mounted to the chassis, I put slightly oversize tires on the chassis and fit the chassis inside the body. If the sides of the mount need some re-contouring to fit the body shape I have all ready done that. I use a little cya to glue the mount to the body while the chassis is screwed to it. I unscrew the chassis and use epoxy to solidly glue the mount in. I drill the holes in the chassis over size to allow the chassis to fit loosely and give some body float. When I put the regular tires back on, I end up with 1/16 or so clearance.

I used to make plastic copies of the old AMT sidemounts which work like Harry's method above. I found it easier to make a one piece mount, as I always end up with mounts being crooked or something. I have used balsa to do the same thing and it can provide lots of options and is easily cut and shaped. Next up method 2.

[mattb]

Here is the tubing method, most used for open wheel cars. The smaller size slides inside the bigger size.
I drill mount holes in the frame (Sprintsplus) and lay the chasis in the body to get appx, length of the mount posts.
Push a drill bit thru the whole and then you can add 1/4 or so to that length. Cut a piece of each size tubing that length.
Screw the smaller piece to the frame and slide the bigger piece about half way over it. You don't care about the mounting height at this time. Mix up some epoxy and put it inside the body where the mount posts will hit. Lay the chassis in and level it or hold it till the glue sets up to keep things level.
P1010036.JPG
P1010038.JPG
After the glue sets up, you just pull the chassis off, the tubing on the frame is not glued, just the big piece that is left inside the body. You can see that the small piece cannot slide up to the glue area when you glue the large posts, it must be kept apart 1/4 inch or so.
P1010039.JPG
When you pull them apart, you can glue the large posts more if they need it or else you just mix some epoxy and slide your chassis back onto the large posts until you have the correct height.

[mattb]

Here's the finished mount on the Harvey Aluminum Special I just started, made the body yesterday! Ready for paint and decals to build the 1962 Micky Thompson/Dan Gurney car.
P1010041.JPG
I have done the two mounting post style on a few full size bodies, but body float is much easier if you use side mounts on the bigger bodies, like Harry's example above. I also have some 1/8 by 1/2 inch plastic sticks that sometimes I have used one behind the front wheels from side to side with a screw on each side and one single post at the rear. Balsa or plastic shapes all offer lots of methods. My biggest problem was always tire clearance and level body mounting and these methods have helped me eliminate that.

[VTECFOUR]

Going to mount my Bugeye body with my usual method, a single post front and rear.

I use brass flat head threaded screw inserts for 2-56 or M2 screws press fit into Evergreen 3/16" styrene tubing.



Screw the insert with tubing onto the chassis and then cut the lengths for my desired body ride height. Then secure to body with 5 minute epoxy, adjusting the position constantly while the epoxy cures in a hurry.



Works well on small bodies.

Dan

[mattb]

Those threaded inserts are a better choice then the brass plated screws I get at Harbor Freight. I have some but don't use them very often. You can get them from McMaster Carr pretty cheap. I should start using them!

[munter]

I use plastic tube glued to the underside of the body just like Dan does. I also support the tube with some popsicle sticks glued in place like a buttress on an old building.

For screws I use a variety but they are all self tapping not machine screws...why? because I want to leave the screw not fully screwed in . This allows body float and the self tapping screw can be left part way home without worry of it coming loose and falling out...(99% of the time)

[mattb]

Also when the self tapping screws start to get loose, I put a drop of cya glue on them and then they won't loosen up. Lot of the cars we race, I have to take apart every week or so and the plastic holes eventually allow the screws to work loose and not hold the right amount of tension.

[munter]

CA glue is your friend and mine too.

Have had the same problem with the holes wearing after many many dismantling and reassembling episodes of club race cars.
I also get it during some scratch builds due to body on, body off, body on, body off scenarios.

[gascarnut]

Look here for a different way to mount bodies: viewtopic.php?f=58&t=16050&start=15

Dennis

[black3sr]

[mattb]

When I have used threaded inserts, I drilled a hold slightly smaller than the insert. Then put a screw in the insert, just one or two threads, not enough to spread it. I hold the screw with a pair of pliars and hold it over a flame to get it good and hot, then push it in the tube while it is hot and melts it's way into the tube and locks itself in. Maybe aqll this isn't necessary. simple epoxy is easier with the right size tube.

One of the guys has a threaded collar he puts over long 4-40 screws and when it is tightened down all the way, it leaves about 1/16 inch of the threads uncovered next to the screw head. He then puts this in his lathe and turns it, and removes the threads next to the screw head with a file, his bodies float easy on this smooth part of the screw, which he cuts off so they bottom out in the insert. All that is too technical and too much work for me.

This is a good thread with lots of ideas.

[HomeRacingWorld]

For the plate style mount, I set the body on the chassis and then use a variety of material to shim the body until the ride height is where I want it.

Then install the plates and tack them in place with CA. When dry, I then add the rest of the adhesive to secure the plates/wood.