I viewed Cheng Concretes instructable on how to make a concrete door stop and liked it very much. I have been making concrete letters for some time and found their technique interesting. See here: https://www.instructables.com/id/DIY-CONCRETE-Door-Stop/. I know, however that their door stop would last about two door openings/closings before it broke at my house. So I thought of how I could make the stop block but do it in a more substantial manner, i.e., one that would last for a good long time. Thanks to Cheng Concrete for their informative and interesting project!
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Step 1: All You Need to Make a Concrete Doorstop
1. First, make the letters for STOP. As suggested by Cheng, I used my word processor, selected "impact font", and sized it to fit on one page, 8.5 by 11, the standard copy paper size.
2. Two cement/concrete products: the first is for the letters themselves and is a product called Cement All. It is used for repairing cracks, anchoring bolts and other, similar tasks. It is rapid setting and is considerably stronger than regular cement or concrete mix due to special additives and hardening agents.
3. You'll need to make a form for the project, mine was cut from scrap shelving, plastic covered mdf and was about 7 by 11 inches.
4. Sundry other supplies/toools such as trowel, wheelbarrow, measuring can, basin to mix in, etc.
5. While the Cheng instructable used a hand held jig saw to cut the foam with, I chose to use my hotwire machine.
6. Styrofoam, or similar product, 1 to 2 inches in thickness. I had some that was about 1.25 in. thick, and this was fine.
Step 2: Cut Letters
Make letters to size you want. Mine are about 4 inches high. See more instructions on photo included.
Step 3: Pin Letters to Styrofoam Block
Secure letters by tacking onto the foam blank. Since I had used regular copy paper, I used more pins than would have been necessary had I used card stock to print out my letters. Either way works.
Step 4: Cut Out Letters on Hotwire Machine.
By using the hotwire, there is no particles of styrofoam flying all over the place and the resulting cuts are very smooth and reguire no further treatment such as sanding to ensure smooth sides of the letters.
Step 5: Make Form
Form is made out of available materials, I had a piece of laminated shelving that I could use. I cut out the four sides which are 4 inches thick, and the base which was 11 by 7 inches. All pieces are then screwed into place with drywall screws.
Step 6: Glue Letter Piece Into the Form
I used Elmer's white glue for my adhesive here. I have found that it dries sufficiently overnight so that It can be used effectively. Alternatively, spray adhesive can be used as well. By painting the styrofoam block first with acrylic paint, the spray on adhesive will not "melt" the foam. It also allows the white glue a better grip. I have used both and either one works equally well.
Step 7: Make Concrete Mixtures: Cement All for Letters; Regular Premix for Base
I mixed the regular cement mix first as it has a longer setting time and can be allowed to sit for 15 to 30 minutes...long enough to mix the the Cement All for the letters, and get that poured into the recesses as shown on included photos.
Step 8: Pour Both Concrete Mixes Into Form
Letters are done first, as shown. I colored the letters with regular colorant so that the final product would have a two tone appearance. The base is poured right onto the wet letters, and will weld or join all parts into one block.
Step 9: Un-Mold the Project
After a cure/setting time of at least 48 hours, the form can be removed.
Step 10: Remove Styrofoam From Letters
Using tools shown, styrofoam is cut or stripped away from letters and base.
Step 11: Put Into Use
This was a fun project, and doesn't necessarily have to be limited to a door stop. Other fonts could be used and garden markers, signs, directional items, etc. could be utilized.