Welder - a simple plugin about constraints

Hey! Glad to see you here, this is Welder, the first plugin I made in Roblox. It was created for personal use as a way for me to replace the old and classic Constraint Editor Plugins with outdated UIs.

After months receiving notifications from this post, I realized that +300 users already saw and got my plugin. Even though 300 is not a big amount of users, it is a big amount of users for me and I thought that re-doing from 0 this plugin to give it a better look would be a nice idea for those +300 developers who use this plugin.


So there it goes; Welder, a simple and lightweight plugin about constraints. Just install Welder, select which Constraint you want to create and create it.

Welder has got a simple and clean modern-looking UI with a bunch of options that are quite handy when creating Welds or Motor6Ds. You can also adjust the size of your menu and the amount of information displayed by the menu.

The plugin interface is pretty self explanatory, but if you don’t understand how to use this plugin check the GIF shown at the beginning.


Welder is free and open-source at github forever, enjoy! This plugin was made for learning purposes.


This should be in #resources:community-resources. But I will definitely check it out.


Plugin is great! It works realy good!


Wow! This looks amazing, and I see that a lot of hard work was put into it. I will use it, looks amazing! Great job. :+1:


Also, sorry for late response. :frowning:

Hey! I recently edited this thread since I decided to make this plugin again from 0 to give it a better look. My apologies if someone got pinged due to my edit.

Anyway, Welder probably changed a lot from the last time you saw it. Not only it has a new UI but also new functions and support for a new object, Motor6D. Welder will also check automatically for updates now so if a new feature or patch comes out, you will get notified in the output.

I would really like to thank everybody who gave me feedback by posting a comment, leaving a like in this thread or just getting the plugin, that really motivated me to start working again.


Well, I got pinged 6 months late so, what did you change about it?

Damn, actually nothing. Just changed its category from Resources to Cool Creations since I really think that there are many plugins and modules that cover this in a better way.

But now you’re asking, some days ago I started using back this plugin for Motor6Ds in my animations and while using it I realized the blurry and low-quality icons, so probably I’ll be changing those. Also though about making it open-source, now that I know how to use github.

Update: As I said, made a quick update just to fix some of those things that I didn’t like about the plugin.

  • New button icons and plugin icon


  • Plugin is now open-source at Github

  • Updated the way the plugin synced its UI theme with the Studio theme, it’s a little bit better now.

  • Replaced all the old wait() with task.wait() from the new task library.

  • Got rid of “math abbreviations” like using local insert = table.insert instead of directly table.insert since those micro-optimizations can’t really be noticed in such things like this plugin. Since now the plugin is open-source, although many will learn nothing from it I wanted to keep the source code as clean and readable as possible.

    Could’ve changed a lot from the source code to make it easier to read but it would’ve take me a lot of time that I don’t want to waste so I just focused on those little things.

  • Added some new warn() that were missing in some situations.

  • Changed a little bit the way in which weld parenting worked. Old behavior was: if you don’t have a parent I’ll make a folder to act as one. New behavior: if you don’t have a parent no welds for you.

  • Changed default and minimum plugin widget size to also include the parent display section since I was tired of manually expanding my plugin widget to check if the parent was selected correctly or not.

  • Changed the way table.insert() was used to match with the new Luau behavior.

    Luau Recap: July 2021

    Behavior changes

    table.insert will no longer move elements forward 1 spot when index is negative or 0.

    This change also fixed a performance issue when table.insert was called with a large negative index.

    The ‘TableOperations’ lint mentioned earlier will flag cases where insertion at index 0 is performed.

  • Got rid of all the :WaitForChild() since they were not necessary due to the hierarchy of the plugin.

  • Added a custom name to the plugin widget to display as WeldingMenu under the PluginGuiService tab instead of PluginWidget.


Does Welder support WeldConstraint? If not i might end up switching the class.

Here you are Sir,


Just keep in mind that welder is not being maintained anymore. Even though it should work like normally, I recommend you to find a more updated and maintained welding plugin that could support all the things you’re looking for (if you’re looking for something more).

That’s ok, I usually use Reclass to change the constraint to the one i wish. I only use welders to help me weld stuff that i needed. Only for me to change the class to the one i truly needed.