Iam working on a project that requires that a bolt be tightened to secure a saw blade. My problem is, I have lost the bolt and is now stuck. I would like to make a mold of the bolt threads ,which are in the motor body, to find the thread size, etc and would like to know what material to use and how to make the mold. I would appreciate any advise. Thanks in advance. Nalom.
I agree with Brian, please use a bolt and don't try to make one. I would make a copy of the threads but ONLY to use it to find a bolt in a hardware store to match what you need. I'm one to prefer making things myself and I wouldn't even attempt to make a bolt especially for anything that needs strength. Now if you're just trying to make a mold to bring to the store to match the bolt, you can use Amazing Mold Putty as it won't drip into places you don't want it to like the liquids and it fully cures in 20 minutes. That said, make sure to be quick when mixing it as it starts setting up at 2 1/2 minutes and you won't be able to do anything with it once it hits that mark.
...I might add either taking the saw, if its portable enough, or remove the motor body from the saw itself and go to your local hard ware store....that way you can test fit the various bolts available for proper fitment and size.....keep in mind this could be a reverse thread bolt which will be a bit more difficult to locate. If indeed it is a reverse threaded bolt ,check with someone who deals with electric motors ....this could be either automotive type (alternators/generators) or AC electric type as they would use the same type of bolt to keep a pulley set attached to an electric motor.
Thanks Brian and Notoes for your prompt and informative replies. Now, here's how I plan to proceed from here, 1. purchase the Amazing mold putty kit,2. mix the resin, 3. pour it into the thread cavity,let it cure 4. insert a small allen wrench into the top of the opening, let the resin cureand 5. screw the molded threads out. Will this work?
If you have the kit, I would use the mold putty instead of the resin to make a copy of the threads - it sounds like you're trying to use the resin as the copy material. The resin will want to bond with the threads instead of making a copy of them so they'll be pretty hard to remove. The mold putty on the other hand is meant to not bond on any surface (unless the surface is a silicon) so it can more easily be removed. Also the mold putty will still be hard enough to hold the shape so you can match the threads.
Think of it this way, when making a copy of something you need a hard surface and a soft surface to make the copy easy to remove. You already have the hard surface in the saw so you need to use a soft surface as the copy. Trying to remove a hard surface from another hard surface can result in one or both surfaces getting damaged.