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Discussion Starter #1
For a quick winter project, I wanted to add the brake duct cooling ports to my beast. I didn't want the shiny silver sink drains, so I bought a new stock lower grill for $37 on ebay and tried drilling my own 1/2" holes for a more stealthy approach. (following the helpful DIYs on this site).

Unfortunately the holes that I made resulted in copious excess plastic shavings stuck on/around the holes... How did I managed to bungle this very simple task?? Maybe my drill bit too dull? Did I press too hard/soft with the drill?

I went around the holes with a skinny file, a razor knife, and even some sand paper... which helped clear away much of the excess, but it still looks like some amateur garage job... which is exactly what it is... but I can't have it looking that way right?... :)

Attached a few photos for illustration. Any ideas what I did wrong? Anyone else have this problem? I'm pretty sure I'll splurge on the $89 grill now with the built in sink drains since this one looks too low rent to mount... I just wish I could find a black sink drain grill instead of the shiny aluminum version...

All input welcome :)

Thanks!! Nathan
 

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Discussion Starter #2 (Edited)
After all my filing/sanding, this is the best I've been able to get it. Better for sure... and one might argue that once it's mounted in the bumper one might not notice such hackish workmanship, but I don't think it's good enough for my standards... Any other suggestions?

Thanks!
 

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Try a round file to smooth things out. For future reference, drill from the front next time.
 

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As Silent said, drill from the front. The cleaner hole will be on the side you drill on, not the exit. Maybe start with one size smaller drill, then go up 2 sizes and just ream/chamfer the holes by turning the larger drill bit by hand on them.

You maybe able to get some needle files and just file out the remaining material in the corners of the mesh and make the mesh look real if you have that kinda time to spare?

There's someone on here selling grills that are complete mesh for under $100 I think? That maybe easier given the time spent on doing the drilling and cleaning it up etc.
 

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Discussion Starter #6
But I did drill from the front heh. Doesn't look that way though does it. The last photo is after 45 mins with the skinny round file. I started with 1/8th inch bit for starter holes in hopes of getting them more even, but that didnt work out all that well. I like the idea of going up two sizes and just hand turning the bit to clear away the edges. Id have to go buy a new bit as 1/2 inch is the largest i have atm.

I really like the idea of an all mesh grill though...That's what I was hoping to find when I started this mod. I did a grill search and all I found was the sink drain options. Any idea who the person was selling them??

Thanks!!
 

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I really like the idea of an all mesh grill though...That's what I was hoping to find when I started this mod. I did a grill search and all I found was the sink drain options. Any idea who the person was selling them??

Thanks!!
Yeah I think it's the way it should have came. I've just been searching to try and find that thread. Haven't found it yet. I think it was only about 2-3 months ago when it was posted? All I was coming up with as the sink drain threads too. I think the poster of said thread was getting the all mesh grills from fee-bay? Maybe in Europe? So maybe a search on there too may yield some results. They were an aftermarket brand I think but looked OEM.
 

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Look at is as a positive outcome. We all break stuff when trying something new or experimenting and sometimes just by having a bad day. The lesson is to learn from these things, but you already know this. You're just fortunate this venture won't cost you more than $100 if you decide to buy another one.


Sent from AutoGuide.com Free App
 
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I would break out the dremel/file and just make those holes square. Some cutting tools don't do well with soft plastic. But you know that now :cheers:
 

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Discussion Starter #13
Yeah, for $37 I was willing to try the diy method... i didht think operating a drill would be too complicated, but clearly it's more of an art form than I anticipated. I might still go after it with the Dremel anyway... great idea Brebdan... how did I not think of that before all that time with the file lol.

Huge thanks to Mordor for finding that for sale link btw. Pretty sure that's the direction I'm headed if my hack job doesn't get much better.

Thanks!
 

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Think I can help you. What you did wrong was use a wood bit instead of a plastic bit. Plastic bits have a drill tip angle of 60 degrees IIRC which is much steeper/pointier than a wood or metal bit. The softer the materiel the pointier the bit will be, is a general rule. The other thing is the drill speed was likely too fast, well atleast for the wrong bit. Lastly if you want a clean hole in metal or plastic coolant/lube is useful.
Here is a simple page with a good explanation.
Drill Bits Designed for Plastics | eHow

It is not screwed yet, you are just not finished. To get a nice clean perfectly round hole you bore with a bit and then ream. You still need to ream. I would suggest that you use a tapered ream as you just want it to look good. The holes don't need to be the exact same size nor a specific size.
These can be purchased for hand or machine. If you are going to do it with a drill it needs to be run slow. Cordless drill will get slow enough, corded drill will likely be too fast unless it was a good quality metal drill. In an hour you could ream them by hand and they will be spotless.
Tapered Reamer | Taper Reamers
 

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Discussion Starter #16
You're exactly right, I used my standard wood bit that I had laying around. Never occurred to me to get a plastic specific bit... I'll see about a reamer or chamfer bit. Sounds like this might be salvageable! Thanks!!
 

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Too late now, since the holes are already drilled, but sharp Spade, Forstner, or Brad point drill bits can give a really nice finish on plastic holes if you go slow rpm. Drill from the front side. These style bits are made for wood, but do a good job on not brittle plastics as they self pilot and then cut the hole perimeter clean at the start of drilling. No wander or excessive flash. Stepped drill bits can do a good job too. A taper reamer or file can likely clean up what you have done already. You can't use one of these wood type bits now that the holes are made. Good luck.
 
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I did the exact same thing and had the same outcome for the same reasons. Looked bad because of wrong bit and no skill. However my solution was simply taking a fairly wide flat head screw driver and basically just scraping the plastic filing mess right off from the front, hole by hole. It's not perfect, but it is 90% better and absolutely not noticeable without standing on your head out in sunlight. You will probably get better results with the fine suggestions for chamfer bits and such, but this worked for me.
 

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It is probably best to simply go with Slimmbones. I have one but waiting for the opportunity to do a bunch of things at the same time.
 

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Plus 1 on the step bit to clean it up. I bet if you put it on the car you would not notice it after a week as it is. It's always dark up there and shadowed.
 
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