I need to fill some holes that were drilled in the wrong place in some sheet acrylic. It is .090" thick. I have Squadron Green Putty and thought of using that and there are fillers available in hardware stores but they have metal in them. I’m not sure how either would look against the acrylic–rough texture against the acrylic’s smooth surface. I will have to paint the plugs white. I also thought of styrene rod, but no one stocks the sizes I need (3/16" and 1/4"). Before I start experimenting with those things, I thought I’d ask here and see if anyone has a better idea. Anyone got any ideas on anything better to use and how to keep the plug from falling out of the hole?
Plastruct Inc makes acrylic rod in the size you need.
Looks like you already got an answer.
Back in the mid '50’s when I first started out as a Gas Fitters Helper for the Gas Company, the fitter that I first went out with kept nagging me with the old carpenters prayer. “Measure twice, cut once”. At 16 years old, I thought that I knew better than that old f**t so when he told me to measure up for a 1/2 dozen pieces of 4" steel pipe that were to be identical lengths at about 15 inches long, I went and did a quick measure. I went out to the truck and proceeded to cut and thread the pieces by hand as we were on a new construction site with no power. Do you know how hard it is to cut & thread 4" pipe by hand with a chain vise bolted to the back of a truck? Long story short, I had to go and do them all over because I cut them all 1" short. [banghead][banghead][banghead] Needless to say, I made sure to listen and do exactly as I was instructed from then on.
As Norm says on the New Yankee Workshop. “Measure twice, cut once”.
Blue Flamer.
BNSFNUT: Yes, I know Plastruct makes it, but no one locally stocks those sizes. I’m trying to avoid ordering from the U.S. and paying shipping on a small order (I live in Canada). Okay, I’m cheap, but I guess I’ll have to go that route
Blue Flamer: It wasn’t a case of cutting wrong, I modified some control panels and there are holes where switches used to be and I changed the mounting method and there are holes where screws used to be. Your pipe story reminded me of something that happened to me as a trainee many, many years ago in the electronics industry. I was installing a rack of equipment that was located under a cable tray. The cables for the rack came down from the cable tray. There were 4 or 6 fifty pair cables that I had to solder connectors onto the ends of. I pulled the cable ends onto a table and spent the best part of a day attaching the ends. When I went to attach the connectors to the rack I realized that I had pulled the cables over the edge of the tray instead of feeding them through the slots in the tray and the connectors were too big to pass through the slots. I had to cut off the connectors, feed the cables through the tray and reattach the connectors. I never made a mistake like that again!
I cut it 3 times and it’s still too short…
Drill 1/4" plugs from a piece of scrap .090" thick acrylic; enlarge your 3/16" holes to 1/4"; wasn’t that simple?.
I personally would use something like this, If I am reading your post correctly You have made some modifications to a control panel and no longer need the switches that occupied the holes in question. So rather then attempt to make it appear as if the holes were never there in the first place I would simply pick the correct size or even the next size up and snap in a plug. Neat and clean and call it done. McMaster Carr has endless uses for the model railroader trust me they have gotten a lot of my business over the years.
http://www.mcmaster.com/#polycarbonate-finishing-plugs/=67s15h
R.T.Poteet Your idea would be the best solution as I could cut the plugs from the same material as the control panel. But… 1) Wouldn’t there be a hole in the middle of the plug from the guide drill if I used a hole cutter? I have heard of special drill bits for making plugs from wood for cabinetry, but I’m not familiar with them. Maybe I’ll check them out in a hardware store. 2) The small holes from the mounting screws are too close to the edges to be able to enlarge them to 1/4". However, you’ve got my thought processes going off in another direction that I hadn’t thought of before. Thanks.
Allegheny2-6-6-6 Hmmmmmm, I think I’ve got some of those things somewhere. I’ll just have to try and find them and see if they’re the right size. Thanks for another idea I hadn’t thought of.
This is on the right track! Or you can do what I do. Cut a square out of some sheet acrylic that is larger than the hole and glue it over the hole to hide it. No one has ever noticed the patch nor have mentioned it to me when looking at my control panel and I have about 4 patches on them…chuck
Bob,
A few questions:
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What is the acrylic you are wanting to till being used for? [Edit: Oops! I just read your comment about the holes being in a control panel, Bob. I would therefore take R.T.'s suggestion: Oversize the hole with a larger drill bit identical to the OD of the rod you plan to fill it with. Only one side needs to be flush so the length of the plug isn’t critical.] -
Is it clear acrylic or tinted? Translucent or opaque?
If it’s clear, use clear silicone adhesive (e.g. DAP) to fill the void. Once the hole is completely filled, the important step is to squeegee both sides of the hole flat with something stiff that won’t also mar the finish of the acrylic. Once the silicone adhesive cures, it will adhere very well to it.
If the acrylic is not clear and will be painted, use a water-based filler. Acrylic is sensitive to stress and solvents - e.g. CA. A filled hole can develop either stress-fractures or discoloration from solvents.
Hope that helps…
Tom
The bit you are refering to is a plug cutter. This link shows a set, but individual cutters may be found (even at a home center/ hardware). 1/4" is the smallest that I’ve found, I generally use a 3/8" regularly.
http://www.jamestowndistributors.com/userportal/show_product.do?pid=501&BECOME
http://www.woodcraft.com/Family/2020057/SNAPPY-Tapered-Plug-Cutters.aspx
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Cover the hole on the front side with vynl tape (Like electrical tape). Make sure it’s stretched tight.
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Fill the hole from the backside with epoxy and you will have a flush fitting plug. Use a toothpick to run around the edge of the hole to remove any air bubbles. I use JB Qwik.
That was the method I was leaning towards and I think I’ll go with it. I’ll be in a large hardware store tomorrow and I’ll see what they’ve got for fillers, but I think I’ll go with the epoxy. No matter what method I use, it’s going to show to some degree or another. I used the fill the hole with epoxy method once before but I had the plug come out when something hit the front of it so I thought I’d try to find something else more durable. Maybe I didn’t get all the bubbles out that time.
Round the edges of the hole from front and back, this will lock the plug in.
I finally got the holes filled. I found a product called PC-11 epoxy paste, made by Protective Coating Co., Allentown, PA in a hardware store. It’s a marine grade 2-part epoxy paste. I chose it because after reading the directions on all the packages of fillers on the shelf, this one seemed to be the easiest to work with. And it cures white, which is a bonus for this application, although it can be painted. It stays workable for 30 mins. after mixing and cures in 12 hours. According to the packaging it can be used to fill holes, cracks, and will bond almost anything to anything, it can be sawed, drilled and sanded, and it cures wet or dry, even under water. I found it very easy to use and it did the job well. The only drawback, and it’s a very minor one, maybe even an asset, is that the paste is quite stiff. At least it means that it’s not going to run all over the place. You just have to make sure you pack it tightly.
Thanks to every one for all your suggestions. Even though I didn’t use most of them, they all gave me ideas to keep in mind for future situations.