Quick tutorial for weld lines using epoxy.

Hokeh!

I was thinking this out the other night to help out builders wanting a better looking weld line. Since most are using some type of 2 part epoxy putty, I think this will really help out.

Lets start?!?

First you’ll have to make the tool. I used a little piece of aluminum I cut to about 2" x 3/4".

About a half inch from the end, drill a hole in the center line about the size of the bead you want the weld to have. I used a 3/16" bit for the bead around the n-filter. Smaller sizes for smaller beads like around gun handles. Then trim off the excess according to the image below.

Next you’ll cut a small section of the epoxy. I have the kind that comes rolled together and you just gut a section off and mix together. Work small because time is short with quick epoxy. About an 1/8" section is enough.

Roll a little snake about the same size as the hole (3/16") and press it onto the edge where you want the weld. Compress it down to about half its original diameter making sure it holds weld to the [clean] surface. Press down along both edges to almost flat with the surface. Wet finger to avoid lifting the epoxy.

Take the tool and quickly start at one end of the line and push down at an angle of about 15-20 degrees. Move up about 3-4 mm and press down for another bead. Evenly repeat all the way down the line. If the tool sticks to the epoxy and lifts it, just keep a little wet sponge to moisten the tool after each press.

As the epoxy is starting to harden, use a razor blade to trim excess epoxy from both sides and use your fingers to press down the edge to blend it into the surface on both sides of the line. Use the tool to retouch any of the beads if needed.

Make sure to work in small sections to avoid the epoxy hardening before you finish the process. About 2" lines.

Now for the illustration.

Awesome! I’ve been using a bent paperclip to make my welds but this is definitely worth a try.

Holy crap! Great idea. Why do you post this when my pack is almost finished? :cry:

Thanks CPU64!

Sometimes its the simplest of things.

Nice!

i used hotglue to secure my rear handle to the gunbox!

it happened by accident!

because i used more hotglue than needed, the more of hotglue swelled out after i pushed it into the right position!

i mean, i was aware about the fact that it would happen, but the idea of using the “not needed” hotglue for the weld line came just before i wanted to clean it up!

i am happy i didnt, so i painted it!

looks also good and is an easyer solution i think

Bump for the newbs!

Awesome. I’ve been looking for this post.

Thx for the bump:)

May be this should be a sticky or tagged thread

Thanks for sharing this; I’m about to add the weld line on our packs, and this is going to be a big help!

Nice tutorial am guna use this method :slight_smile:

Another thing that I had done (by accident at first) was I used gorilla glue to build a lot of my pieces. It expands and bubbles up nicely creating little weld marks. It certainly isnt as easy to control but it looks pretty good at the end.

The pic is not the greatest but hopefully it shows what im talking about. everyone who seen my pack thought it was welded up out of steel.

Just discovered the tutorials section you all have here and I’m LOVING these!

I’m in process of my very first scratchbuild and opted to use styrene for a majority of the build

I’m tackling the EDA this weekend then the ION Arm next but i’ve been racking my brain on techniques for how to make the weld lines. Then like god-rays after a heavy rain I come across this thread! Just what the Dr. ordered.

thanks CPU64 and evallded, I’m definetly going to test out both of these weld-line method to see what works best for me

Hay anyone tried using crayola foam clay…that stuff works amazing

The only problem with it though is that it can shrink and crack during the drying process

True True

SO after using Crayola foam clay it worked out PERFECT!!! It was easy to use and once i spray painted it it become twice as tough. The best part is since its black foam if it gets chipped its black underneath and easily fixable

Sorry for the blurry image. Ill get a better one.

I had a thought occur to me today. I’ve been trying to make weld lines with epoxy and mark it like posted in the beginning of this thread. Why don’t I try to make lines the same way welders do? Instead of a tig welder, I can try to use a syringe (no needle) with epoxy or bondo and work on my welding technique.

Of course, 5 minute epoxy is too dense to go through the syringe, but here is a pic of my first attempt using bondo. The one closest was the first line, farthest being last, and a little difficult as the bondo was starting to set already.

![image](http://www.gbfans.com/images/pb/Hudgensusaf/Mobile Uploads_20140203_234626_RichtoneHDR.jpg)

Please, give me some input whether or not I’m just asking for trouble doing this, because I’m sure somebody’s done it before at some point.

Technique for this method is key, and will definitely take practice to make it look really good.

That is basically the hot glue technique. The problem is, Bondo is not a sculpting material. It will become brittle and chip very easy. It is meant to be used in very thin layers. 2 part epoxy is a lot stronger than bondo.

Thanks man! This tutorial helped me, looks way better than the bead method.

This is what I did with the “bead” method.

…And this is with your tool method!

Way better!