frame

[dozer]

What is the best way to stretch frames ? anybody have pics! Thanks Dozer!

[The Modeling Hermit]

I'm not up to the quality that many of the other members are, but I cheat and use a donor frame. I decide how long I want the extension to be, and then I just simply cut the frame pieces at the desired location. From the donor piece, I cut the length that I need, and put it in place. I then use Plastruct or scrap pieces to back the splice. I use just a touch of Testor's tube glue to hold the pieces in position, and after I'm satisfied with the fit, and the glue has set enough to hold it there, I add liquid glue to bond it.

Do remember that when you stretch a frame, that it might be enough to also have to include another cross brace. You will also have to lengthen the driveshaft. These are not hard to do; you will just have to plan for them.

In this picture you can see where I've made the cuts and splices. This is for a wrecker rebuild that I've been working on.

After things have set up and are secure, I do the necessary sanding and smoothing. After that I go in and do the rivet and bolt detail. I'm sure that there are others that have a much better technique than mine, but this works for me. I hope this helps.

Edited March 11, 2009 by Kodiak Island Modeler

[SpreadAxle]

What Douglas is showing in his pix is pretty much how I do it. You will note the plastic pieces at the joints in the frame section for strength.

What I usually like to do is use a crossmember right at the joints to add strength. This is where I always start. Also, another thing I do for strength is if it's possible, mount things like fuel tanks, toolboxes, or whatever on the outside of the frame rail at the joint. If you straddle a fuel tank(for instance) across the joint, it is glued to both sections of the rail, and covers up the joint if you can't get it to look right. Even a deck plate right there helps. All that is just my long winded way of saying never rely solely on just glueing the ends of the frame rails together.

It's my understanding that when real trucks have their frames stretched, we'll use the example of a conventional with a sleeper, the cut in the frame is usually made under the sleeper. Doing this, allows you to mount the fuel tanks as I mentioned, and, will hide flaws. Or if it's a straight truck, which usually has a longer frame, make your cuts where the truck body will be sitting over the top of the splices. The body will be glued to both sections, giving the rail sections the added strength of being glued to a large item.

Also, from watching Mackinac359's recent work, if you get the right size Evergreen/Plastruct channel, cut to desired length, you can use your existing frame rails as a template for detailing the new rails, including shaping the front and rear ends of the frame rails. You will then have a one piece, stronger frame rail, then you can use the kits crossmembers to tie your rails together. It's something I will be trying on a future project.

Edited March 13, 2009 by FlatbedKW

[The Modeling Hermit]

Dozer, notice the area between the spices. That's where I added a cross brace as Ray mentioned. The wrecker body covers most of the spiced area, and where it doesn't, I've added fuel tanks and other items to span the spices. One thing that I forgot to mention, is to make sure your measurements are correct. One doesn't want a truck where the front goes one way and the rear goes another. LOL

[cargostar]

Also, make sure that your splice plates are exactly the same length, or else one side of the truck will be longer than the other!

[dozer]

Also, make sure that your splice plates are exactly the same length, or else one side of the truck will be longer than the other!

Once again thanks guys for all the info! The rivet & bolt detail is it just for looks or does it help hold things together? I don't have either item so I will have to locate those items.

[Aaronw]

I do pretty much as described by the others but have found off setting the cuts provides a stronger joint.

When possible I will try to cut one side 1-2" off from the other side, that puts the weak point at differant spots and reduces the tendancy for the frame to want to break in half.

[mistermodel]

I do pretty much as described by the others but have found off setting the cuts provides a stronger joint.

When possible I will try to cut one side 1-2" off from the other side, that puts the weak point at differant spots and reduces the tendancy for the frame to want to break in half.

I off set the cuts on the last one I did,its much better.I also cut the frame on an angle wrather than straight.This gives more glue surfice,and its how its done in 1:1

[The Modeling Hermit]

Dozer, for our purposes the detail is cosmetic. Any place where there is a cross brace or attachment there will be some means of connecting it. You can use other cross braces for a pattern.

[dozer]

Dozer, for our purposes the detail is cosmetic. Any place where there is a cross brace or attachment there will be some means of connecting it. You can use other cross braces for a pattern.

Thanks again for all the info It will be very useful! I have another question what size channel are you guy's using I have the international f-2575 model and my frame rails measure 7/16 or 11mm and I can't seem to find any styrene that size. All I can find is 5/16 at Riders.

[cargostar]

The frame size depends on how the truck is Spec'd. IH S-series frame were 11",with an optional 12" frame and various reinforcments available. Most other builders are 11 or 12". I have used Plastructs 1/2" I beam for a couple of frames, you just have to trim the flanges from one side.

[SpreadAxle]

Also, make sure that your splice plates are exactly the same length, or else one side of the truck will be longer than the other!

Note that sometimes this is the hard part. Check measurements often as looks are decieving. I've had to redo frames that looked perfect until I went to mount items like the front and rear suspensions.

Edited March 13, 2009 by FlatbedKW

[Aaronw]

Note that sometimes this is the hard part. Check measurements often as looks are decieving. I've had to redo frames that looked perfect until I went to mount items like the front and rear suspensions.

I always re-assemble the frame against a straight edge. It isn't foolproof but it does make measurement errors more noticable while there is still time to fix them.

[SpreadAxle]

I always re-assemble the frame against a straight edge. It isn't foolproof but it does make measurement errors more noticable while there is still time to fix them.

Good point. I had a bad habit of doing it by eye. I'm going to try the straightedge next time, along with some other cool ideas I read.

Edited March 16, 2009 by FlatbedKW

[dozer]

Thanks for all the tips I have ordered some parts. Does anybody have more pics? Thanks Dozer

[mackinac359]

One of my first Trucker's Corner columns was titled "Frame up" and discussed the methods of frame stretching and cutting.

I can't remember which issue it was. Anyone? (my mind is a blur anymore)

Tim