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geekhack Projects => Making Stuff Together! => Topic started by: berserkfan on Sun, 24 August 2014, 15:34:09

Title: cutting of Model F AT and other plates
Post by: berserkfan on Sun, 24 August 2014, 15:34:09
I want to mod my F AT. How do I cut the plate to accommodate two new keys next to the spacebar? I have seen very little treatment of this topic and it seems everyone has the cutting wheel WCass mentioned. My dremel set lacks such a wheel, and I am trying to figure out what else I can do. The plate is pretty heavy duty.

Are there ways by which amateurs like me can cut keyboard plates (as well as make switch moddable plates by cutting notches) safely using commonly available power tools?
Title: Re: cutting of Model F AT and other plates
Post by: fohat.digs on Sun, 24 August 2014, 15:52:23
The Dremel cutting wheels are cheap, you should get one. There are also little spherical or conical grinders (just like the dentist uses on your teeth!) that might help.

Otherwise, you might consider drilling holes at every corner (and perhaps in between) and cutting the rest with a very thin saw blade or file.

A cutting tool on the Dremel is by  far the best option.
Title: Re: cutting of Model F AT and other plates
Post by: berserkfan on Sun, 24 August 2014, 16:01:11
The Dremel cutting wheels are cheap, you should get one. There are also little spherical or conical grinders (just like the dentist uses on your teeth!) that might help.

Otherwise, you might consider drilling holes at every corner (and perhaps in between) and cutting the rest with a very thin saw blade or file.

A cutting tool on the Dremel is by  far the best option.

care to show me some photos? I have zero experience dremeling and have literally no clue how to use a dremel successfully. I do have plenty of these round/conical attachments although they seem to have zero effect when trying to cut sideways into a steel plate. When going top down as in trying to drill a hole, they simply won't stay still. Pre punching a dent using a hammer and nail, holding dremel with both hands, don't help.

my dremel is 8000 rpm and seems weak.

what can I find that can cut notches into a keyboard steel plate for switch modding or inserting new model F barrels?
Title: Re: cutting of Model F AT and other plates
Post by: E TwentyNine on Sun, 24 August 2014, 18:57:55
There might have been an easier way, but I use a combination of a cutting wheel, cutting bit, and a drill bit.

Here's the different types of the first two:

http://www.dremel.com/en-us/Accessories/Pages/SubCategories.aspx?catid=2058

http://www.dremel.com/en-us/Accessories/Pages/SubCategories.aspx?catid=2060

I used the brown cutting wheels, they broke occasionally but worked.  I didn't use a dremel though, have a rotary tool with adjustable speed, don't even know the brand, something I grabbed at a big box store years ago.

The thing is you don't need to be super precise.  When you get the barrels mounts in there, the square base butted up against the spacebar base keeps things aligned.

My results are in my sig: http://geekhack.org/index.php?topic=52379

You can see some of my cuts are far from perfect but the keyboard ends up spaced out fine.
Title: Re: cutting of Model F AT and other plates
Post by: berserkfan on Sun, 24 August 2014, 22:51:19
There might have been an easier way, but I use a combination of a cutting wheel, cutting bit, and a drill bit.

Here's the different types of the first two:

http://www.dremel.com/en-us/Accessories/Pages/SubCategories.aspx?catid=2058

http://www.dremel.com/en-us/Accessories/Pages/SubCategories.aspx?catid=2060

I used the brown cutting wheels, they broke occasionally but worked.  I didn't use a dremel though, have a rotary tool with adjustable speed, don't even know the brand, something I grabbed at a big box store years ago.

The thing is you don't need to be super precise.  When you get the barrels mounts in there, the square base butted up against the spacebar base keeps things aligned.

My results are in my sig: http://geekhack.org/index.php?topic=52379

You can see some of my cuts are far from perfect but the keyboard ends up spaced out fine.

Here is my result.

10 minutes. My hands feel awful trying to hold that thing steady.

Result? Negligible.

I had nearly as much success using rough sandpaper on the rust spots.

I switched to a drill because the cutting wheel broke right away. You can see the pieces.

Any suggestions welcome! I can't find a metal shop that will help me cut plates locally, or I would try them also.
Title: Re: cutting of Model F AT and other plates
Post by: berserkfan on Mon, 25 August 2014, 00:45:46
fohat and friends

at this point I am desperate. Have not been able to find metal shops locally that can cut plates for me. I have a bunch of intended projects to do over the next few years, and I expect to do cutting of various keyboard plates or casings (Model F and others, so the standard is 1.5mm thickness steel). Sometimes I need to cut holes for switches and stabs and I also expect to cut a lot of, a lot of notches for switch modding. I don't have to be very exact and don't consider it important to have nice finish. I am also budgeting up to $200 on tools and $50 more on protective equipment.  (I only have low end gloves, clamps and glasses / face mask now.)

What should I go for and what should I start reading up and research on? I originally thought that I could buy a low end plasma cutter, until further research told me that I would have to buy a lot of protective equipment, compressed air, and other things I simply am not aware of.

Title: Re: cutting of Model F AT and other plates
Post by: jacobolus on Mon, 25 August 2014, 03:59:52
Where is locally? Maybe someone else around here knows of metal shops (either near you or elsewhere) that have a waterjet or similar, and don’t charge inordinately much for custom one-off jobs?
Title: Re: cutting of Model F AT and other plates
Post by: Oobly on Mon, 25 August 2014, 04:47:24
First off, drills usually don't have hardened cutting edges on the sides, so you're not going to get far like that.

Better to drill an outline of holes using a small bit and file between them using a small file. Or find a big HSS bit the right diameter for the hole. Or use a stepped hole cutting bit. Or use a grinding bit on your Dremel. Or use a fret saw. Or a jigsaw with a narrow blade. Lots of options, really.

With just a drill, jigsaw and some files you can do a lot of mods to a plate.

For cutting plates a waterjet is very good, but rather expensive for a small home shop and I don't expect it will pay for itself with the type of work you'll do with it. I suggest you find a nearby shop that has a water cutter and use them when needed.

I don't consider adding notches to an existing plate for switch modding to be worthwhile. Better to have a new plate cut on a water or laser cutter. It's about the same amount of work as far as the cutter is concerned and you don't have to align the plate precisely before cutting. Manually cutting notches is way too much work.
Title: Re: cutting of Model F AT and other plates
Post by: berserkfan on Mon, 25 August 2014, 06:48:31
First off, drills usually don't have hardened cutting edges on the sides, so you're not going to get far like that.

Better to drill an outline of holes using a small bit and file between them using a small file. Or find a big HSS bit the right diameter for the hole. Or use a stepped hole cutting bit. Or use a grinding bit on your Dremel. Or use a fret saw. Or a jigsaw with a narrow blade. Lots of options, really.

With just a drill, jigsaw and some files you can do a lot of mods to a plate.

For cutting plates a waterjet is very good, but rather expensive for a small home shop and I don't expect it will pay for itself with the type of work you'll do with it. I suggest you find a nearby shop that has a water cutter and use them when needed.

I don't consider adding notches to an existing plate for switch modding to be worthwhile. Better to have a new plate cut on a water or laser cutter. It's about the same amount of work as far as the cutter is concerned and you don't have to align the plate precisely before cutting. Manually cutting notches is way too much work.


Oobly, the white patch on top was caused by my small drill bit moving around and not getting any holes drilled. In theory I was trying to drill some holes from the top (that was my smallest bit) and use a file on the rest.

I will look at some of the keywords you’ve used eg stepped hole blade which I’ve never heard of, but I am not sure of you have ever done any of this before. Nothing I have has made any traction on various steel plates I’ve tried. Only one file has made progress and I’m not doing that again.

Everyone says its easier to get a new plate cut. I’d like that in theory also. In practice I have not found any shop willing to do the work for $50 a plate. (Note these are one off, not group buy, projects. But even being to pay modestly more isn't working.)
Title: Re: cutting of Model F AT and other plates
Post by: fohat.digs on Mon, 25 August 2014, 07:42:53
Patience.

Often, starting to drill a hole in metal is the hardest. I put down a small piece of masking tape and drill through it to keep the drill from walking. You can also use a nail as a punch to make a crater (I use nails because they are cheap and I don't want to ruin multiple awls).

In order of preference for cutting something metal, my preferences are: hacksaw>file>drill>Dremel

For the Dremel, there are metal cutting wheels (like mini circular saw blades), discs (flat disposable discs that screw onto a shaft), and a variety of cutting bits and burrs. Often I wind up using more than one of these attachments during the process.

I will drill small (1/16" or 1.5mm-2mm) holes at every corner and cut between with cutting wheels and/or discs. These are ceramic or fiberglass discs coated with ceramic crystal dust and you must use the edge without applying more than the slightest pressure. You should assume that each cut might take several (perhaps many) minutes and you will break and/or wear down a disc with for every 1-2 holes.

I have not done the ANSI mod on my F AT yet, although it has been near the top of my project list for over a year.
Title: Re: cutting of Model F AT and other plates
Post by: dorkvader on Mon, 25 August 2014, 07:57:47
Also when using the cutting wheels on your rotary tool, I would turn the speed all the way up and cut with speed not force. Don't apply force to it to keep the cutting wheel from shattering.
Title: Re: cutting of Model F AT and other plates
Post by: berserkfan on Mon, 25 August 2014, 11:13:56
Patience.

Often, starting to drill a hole in metal is the hardest. I put down a small piece of masking tape and drill through it to keep the drill from walking. You can also use a nail as a punch to make a crater (I use nails because they are cheap and I don't want to ruin multiple awls).

In order of preference for cutting something metal, my preferences are: hacksaw>file>drill>Dremel

For the Dremel, there are metal cutting wheels (like mini circular saw blades), discs (flat disposable discs that screw onto a shaft), and a variety of cutting bits and burrs. Often I wind up using more than one of these attachments during the process.

I will drill small (1/16" or 1.5mm-2mm) holes at every corner and cut between with cutting wheels and/or discs. These are ceramic or fiberglass discs coated with ceramic crystal dust and you must use the edge without applying more than the slightest pressure. You should assume that each cut might take several (perhaps many) minutes and you will break and/or wear down a disc with for every 1-2 holes.

I have not done the ANSI mod on my F AT yet, although it has been near the top of my project list for over a year.

OK fohat, for the immediate F AT conversion project what do you recommend? All I need to cut are two relatively small semicircles, and it's such a pain.  :mad:
Title: Re: cutting of Model F AT and other plates
Post by: 0100010 on Mon, 25 August 2014, 11:26:46
Could you fit one of those hand held hacksaws in there to get a cut started?

(http://images.lowes.com/product/converted/076812/076812069160lg.jpg)

You should be fine with a cut off wheel on a dremel.  I use low speed and low pressure myself - and tape off the entire surrounding area.  That way when you slip (and you will), you don't mar up anything else.  Saftey glasses are a must!
Title: Re: cutting of Model F AT and other plates
Post by: 0100010 on Mon, 25 August 2014, 11:38:46
Maybe this video will help?


It is correct in that you can't use the cutoff wheel to cut a curve.  But what you can do is cut a series of straight slots to the curve and then remove them one by one - like this :

(http://collectiveidea.com/assets/50c74364dabe9d0bda00ccfe/original/IMG_0006.jpg)

Then once you have the curve roughed out - you can clean it up with a cylindrical abrasive bit.
Title: Re: cutting of Model F AT and other plates
Post by: wcass on Thu, 28 August 2014, 14:45:09
Use a cutting disk to make cuts like the blue lines in the picture below. Go very slowly - if the motor starts slowing down more than a little, you are trying to go too fast.
[attachimg=1]
Then go back over it cutting down the center of the "teeth" until there is no more "teeth". Finish off with a grinding bit.