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javafiend
05-13-2005, 10:08 AM
I figured this would be the place to ask my questions since I've seen some of the things I've been trying done so well here.

1. How can I cut L-shaped aluminum at 45 degree angles to build a frame?
I've tried doing this using a mitre box and hacksaw, but the cuts come out so inconsistent that the pieces don't line up.

2. What are the best methods of cutting plexiglass?

Crimson Sky
05-13-2005, 11:46 AM
;) A rough cut with a hacksaw and then a cleanup with a benchtop disk sander (http://www.grizzly.com/products/item.cfm?itemnumber=G0547) that has a tilting table and miter gauge is the least expensive way to get precise 45 degree corners. A small (say 9-14") bandsaw (http://www.grizzly.com/products/item.cfm?itemnumber=G1052) is a great replacement for that hacksaw as well.

If you get a combo disk/belt sander, you can clean up (straight) plexiglas edges and cuts on the belt section. I suggest a 4x36" belt size minimum. I decent jigsaw will make nice cuts in plexi with the proper blade. Also, nothing beats a set of good hand files (http://www.grizzly.com/products/item.cfm?itemnumber=G8073) for fine cleaning up of both plexi and aluminum cuts.

Lots more info can be found in my book the MaximumPC Guide to Extreme PC Mods (http://www.amazon.com/exec/obidos/ASIN/0789731924/thebestcase06-20/002-8841673-2223222?creative=327641&camp=14573&link_code=as1)

http://www.thebestcasescenario.com/gen_images/scratchbuilt-assemble9-(2).jpg

javafiend
05-13-2005, 01:11 PM
Wow, those definitely look like they would get the job done. Unfortunately, though, my workshop and budget are both small and I don't think my wife would necessarily approve those purchases. I currently have an assortment of basic handtools (hammer, saws, assorted pliers, files, and screwdrivers), a drill, and Dremel with various accessories including rotary tool attachment. If new tools are needed, I could probably squeeze $40-$50 out. This budget would also need to cover a framing clamp, but I'm not sure if that is necessary or not. What other tools might I need to complete these corners? I'm not above using handtools and a bit of elbow greese if I have to.

Crimson Sky
05-13-2005, 01:54 PM
welp then get some good files like I said, and maybe a machinist's 45 degree square-a bench vise--and just file clean by hand, using the square as a guide to check for accuracy

Guttenaffe
05-14-2005, 01:52 AM
Use a butane torch to lightly heat the edge of the plexie after you file/sand it smooth and you can remove the "white" look it will get.
The trick it to not over heat the plexie and make little melt marks in it.

I only use butane because other gases seem to burn "dirtier" and I never like their look as well as the 1300deg blue butane flame. Plus most butane torches are small and easier to deal with in small areas where you may have cut.

javafiend
05-16-2005, 08:19 AM
Would you get the same effect with a heat gun as you would a butane torch? Or is there a level of control you have with the torch that you can't get with the heat gun?

Would this fill the requirements of the band saw and benchtop disk sander mentioned in Crimson Sky's reply:
Dremel Scroll Station (http://www.homedepot.com/prel80/HDUS/EN_US/diy_main/pg_diy.jsp?BV_SessionID=@@@@1797778591.1116245487@ @@@&BV_EngineID=cccgaddejfgfmdhcgelceffdfgidgmk.0&CNTTYPE=PROD_META&CNTKEY=Super%20Categories/Tools%20%26%20Hardware&MID=9876&pos=p07) ?

Xato
05-16-2005, 09:53 AM
I didn't notice the disc sander on that dremel station at first. As far as the sander would go, it seems that it would serve the purpose. Even tho i hate tiny little disc sanders like that. =P
I would also like to express my extreme hate for scroll saws at this point. (they are the ones that bounce up and down to cut right? i'm not sure if i have the name right) And in the case that it is a scroll saw, i cant see it being a very good metal cutter.

Lol, i love how you're still pimping your book out crimson =D... i've been looking around for a copy down here in Oz, might have to get it shipped if i cant find it.

Guttenaffe
05-17-2005, 01:55 AM
Xato is right, a Band Saw is better for metal cutting, due to constant downward force, but not everyone can afford or has space for one.

If your jig/scroll saw has a good foot on it and you use it properly you can cut metal with the right blade if it has a good motor.

As for the heat-gun, hmmm I don't think I'd use one they have a large area of effect and would be anoying in tight spaces. A little torch made by Ronson is sold at wal*mart for ~$25 with hot air attachments.

javafiend
05-17-2005, 10:51 AM
Thanks for the tool tips. I'm might be rethinking the scroll station. That's ok, it's not like I was going to get it anytime soon...

I kind of figured that would be the case with the heatgun/torch comparison. Now to convince my wife that I can find a safe place for one. How does it work for heating the acrylic for shaping and will it work for other materials as well?

I picked up a corner clamp from Home Depot the other day and managed to finish the case door frame I'm building. The corners are definitely not perfect, but they'll do for now. The clamp helped a lot with joining the corners. I had to do a lot of filing just to get them to the point they are now. I'll try to post a worklog with pics sometime today or tomorrow to give anyone interested an idea of what I'm doing.

Xato
05-17-2005, 09:54 PM
Yeh, most of the time i use a jigsaw with metal blades (the teeth are much smaller and closer togethor) when doing metal working, as i dont have a band saw of my own. It serves my purposes. I would suggest starting out with tools such as that (hand based), and not delving into the larger 'station' based tool until you think your work quality is being reduced by not having them. Unless you have the spare cash ofcourse =P

But of course, modding is an art, and whichever way you think will get the best results is up to you. Though i will definately be on the cheaper side of modding for a while =D

Guttenaffe
05-18-2005, 03:22 AM
One thing annoying about a band saw is making an inside cut without an exit or entrance…

JesDer
05-18-2005, 11:36 AM
If your jig/scroll saw has a good foot on it and you use it properly you can cut metal with the right blade if it has a good motor.


The Dremel brand scrollsaws seem to be decent. I picked one up a while back and have been happy with it.

Malatory
05-18-2005, 03:21 PM
Plexi also has less clean up if you cut it slowly. if it melts as you are cutting it. Then your cutting it way to fast.

javafiend
05-18-2005, 03:35 PM
I read somewhere that a rotary tool cuts plexiglass pretty well. Is that true? I have the rotary tool and circle cutting attachments for my Dremel and was thinking about using those for the straight cuts and opening for the fan grill. I also have a basic acrylic cutter, which would only be used for straight cuts. What would be the better tool to use?

Malatory
05-19-2005, 10:12 AM
I read somewhere that a rotary tool cuts plexiglass pretty well. Is that true? I have the rotary tool and circle cutting attachments for my Dremel and was thinking about using those for the straight cuts and opening for the fan grill. I also have a basic acrylic cutter, which would only be used for straight cuts. What would be the better tool to use?

usplastic sells router bits to cutting plexi (Plastic based products) it is for a low RPM based router.

I used a dremel with a drywall bit (Has more cutting teeth and will cut through at a higher temp) @ the slowest speed. I rushed things and shattered one peace of acrylic that I was trying to cut.