Clamping quandary

[slownlow]

I had a situation where I needed to clamp an area where none of the clamps I had would work. Then remembered how my dad repaired a cracked canoe paddle. It worked well and the only refinement would be to create an X

 

 

 

 

 

[Ace-Garageguy]

Looks really good.

Another option might be these welding clamps for holding sheetmetal flush...or getting crazy and making up some small ones for model work:

 

Edited December 8, 2024 by Ace-Garageguy

[peteski]

I guess I have hard time seeing a "clamp" (at least going by what the word "clamp" means to me). Are those metal staples considered clamps?

[Ace-Garageguy]

1 minute ago, peteski said:

...Are those metal staples considered clamps?

Not really, but they do solve the "clamping and alignment" problem.

A more exact term might be "temporary alignment and fixturing solution employing wire as staples".  

[slownlow]

45 minutes ago, peteski said:

I guess I have hard time seeing a "clamp" (at least going by what the word "clamp" means to me). Are those metal staples considered clamps?

Maybe I should have included a picture of the other side too. The wires are fed through pre drilled holes and then twisted together. The loop created becomes smaller as the wires are twisted and the gap between the panels closes and tends to maintain the curvature of the panels.

[peteski]

Ah, ok, so that's the clamping action. Got it!

[Bills72sj]

I may have attempted your task with mini magnets. Assuming they have enough strength to accomplish the alignment part.

[peteski]

To be honest, I would feel weird  about building a model where certain parts will be assembled under stress.  I would be worried that after some time problems (such as cracks) might develop.  When customizing 1:1 vehicles, the body's sheet metal can be shaped (bent, etc.) so any stress is minimized, but with plastic the stress will remain forever.

Maybe that's why I don't do any serious body customizing on my models.

[Speedpro]

Instead of using wire or magnets, just take small strips of 0.030 sheet styrene, set the part in place and glue the strip to the outside of the body part that is being joined staying away from sharp radiuses and it's done. Finish glueing the part in place and sand the strips off. Seems like a lot of work using the wire method.

If the part is cut correctly, you won't need any of this stuff anyway. Better results. 

[1930fordpickup]

I like this idea. Plastic models do not always give a perfect fit option when it comes to modifications. Different ways to clamp or hold while the glue dries are always welcome.

[slusher]

On 12/14/2024 at 1:49 AM, 1930fordpickup said:

I like this idea. Plastic models do not always give a perfect fit option when it comes to modifications. Different ways to clamp or hold while the glue dries are always welcome.

I have small Ratchet clamps that work good on most tasks..

[Oldriginal86]

In the boat building world that is called “stitch and glue “ construction.

[slownlow]

On 1/2/2025 at 7:13 PM, Oldriginal86 said:

In the boat building world that is called “stitch and glue “ construction.

Just when you think you’ve come up with something new. 

[Chariots of Fire]

I agree with Pete.  Gluing plastic together while it is under stress is asking for trouble.  Not only is there a good chance of misalignment but the bond is not going to be as strong.  Better to work the parts until they fit or do a tack job with the glue in only those places that meet without clamping and then filling in the gaps with small pieces of plastic.  Small gaps can also be closed by putting glue in the joint, wiping off the surface and then sanding the joint before the glue sets.  Sanding residue mixes with the glue and forms a good bond.

[slownlow]

On 1/27/2025 at 3:54 PM, Chariots of Fire said:

I agree with Pete.  Gluing plastic together while it is under stress is asking for trouble.  Not only is there a good chance of misalignment but the bond is not going to be as strong.  Better to work the parts until they fit or do a tack job with the glue in only those places that meet without clamping and then filling in the gaps with small pieces of plastic.  Small gaps can also be closed by putting glue in the joint, wiping off the surface and then sanding the joint before the glue sets.  Sanding residue mixes with the glue and forms a good bond.

There seems to be  misunderstanding about my reason for clamping. This technique is to hold seams in alignment while the glue dries. The cuts serve two purposes. One is to remove material. The second is to relieve stresses and as modeling  plastic is not a rigid material it will tolerate some distortion with no ill effects. The Mercury pictured has a pie section just below the contour line starting at the front of edge of the doors and growing to 1/8” at the back. A stress point is created at the front as the two portions are brought together. The model is 20+ years old and is showing no ill effects.

[johnyrotten]

6 hours ago, slownlow said:

There seems to be  misunderstanding about my reason for clamping. This technique is to hold seams in alignment while the glue dries. The cuts serve two purposes. One is to remove material. The second is to relieve stresses and as modeling  plastic is not a rigid material it will tolerate some distortion with no ill effects. The Mercury pictured has a pie section just below the contour line starting at the front of edge of the doors and growing to 1/8” at the back. A stress point is created at the front as the two portions are brought together. The model is 20+ years old and is showing no ill effects.

I fully understand this technique,  on certain jobs in my profession I've welded blocks to plates in order to push/pull them into place, either with clamps or hydraulic force. This is similar,  and as long as the "stiches" aren't too tight and methodically spaces, MOST stresses can be controlled and minimized. I like the idea, there's 1000 ways to get something done, this is another tool in the belt. 

[Chariots of Fire]

Has anybody checked out Doug Whyte's U-tube video on how he blended in body sections without glue!   Kind of a neat way to do things. 

[johnyrotten]

15 hours ago, Chariots of Fire said:

Has anybody checked out Doug Whyte's U-tube video on how he blended in body sections without glue!   Kind of a neat way to do things. 

That was the altered wheel base video, correct . If so I watched it. Cool technique, yet another way to do something. And another tool for the arsenal, so to speak. 

[Skip]

On 1/2/2025 at 5:13 PM, Oldriginal86 said:

In the boat building world that is called “stitch and glue “ construction.

I thought the same thing; with the stitch and glue technique, the stress may be minimized by doing the stitching progressively. Place a stitch or two then glue…. Until the panel and contour you’re looking for is close enough to finish off with filler. This also might be an application where either medium Viscosity Super Glue and Baking Soda or Acrylic powder is mixed onto the body work then sanded in. Creates a harder than styrene filler which is less prone to cracking. I have also used the lightweight fiberglass cloth the kind for RC Aircraft modeling.  The super glue as it is lighter than most of the common hobby shop and big box polyester resins, without going something specialized read that expensive resin. Work the superglue into the mat just like you do with resin, it will set much like resin as well. I was thinking this might be used to reinforce the inside of your bodywork and be thin enough to work around.

idea #2. Create a lofted latticework which fits the contours of the interior, a contour gauge (pin gauge) would be useful here to get the outside contour minus the thickness of the body will give you the inside dimensions of a part or panel applied lofted section. Depending on how much the contour developers the contour splines (cross ways) could be spaced every 1/4 to 1/2 inch with 2 - 4 stringers to connect the contour splines. Which is exactly what you’re creating cross slices along the bodywork, you’ve likely seen this type of latticework lofting on shows featuring Foose and other custom bodywork shops.  Ace has probably done this too in some of the plaster and plastics shops he’s worked at, with 3D printing I fear this old technique could be lost.  In some of the more intricate contour development the splining may run lengthwise as well, normally in the aircraft  tooling shop I worked the contour between splines would be filled in with either self curing modeling clay or just plain old plaster.  Something like lofting might be way overkill just to develop a clamping point. Although it could work on a less developed lofted section too where you develop the contour over a shorter section to give a clamping point.  

You are only limited by what you can dream up, any tool you can get the job done and it works is the tool needed, who cares what it looks like it’s not the finished product anyway!