A simple copy jig for Proxxon Mill ??

Tony P said:
The MDF is bolted on the X/Y table yes. The aluminum bar has two feet the small round one and a bigger block of aluminum on the right. Agree the shorter the guide pin the easier it’ll be to stay parallel. The template is wood here but I wouldn’t use that in practice. I have Teflon I can use for templates, the pin will slide easily, it’s tapered and round at the very tip. Clamping both template and work piece will be dependent on how many and how complex they are. Maybe I’ll make a piece of plexiglass as big as the MDF and drill and tap it like my other one then I’ll have many work holding options. The work piece is not going to be easy to hold, have to think of something. Have to test it still as it is. I want to try to mill on the side closest to me too to get a true copy not a mirrored one.
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Now that I'm viewing your photos on something other than my phone, I can see the bevel in the end of the guide pin. very nice.

It looks like you have the same cross-slide as I do, but I feel like I'd have too much slop if I put a table that big on it. I like yours, though.
 
This morning I started changing it. Different work piece holder. Tomm I’ll drill and tap it, it’ll be much better, I found a piece of aluminum I missed the other day. I’ll be able to mill both with the pattern in front and in back of the mill. The compound table came with the mill. The big table is only for the copying parts process. This plexi pictured is for normal milling.

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What did you use for spacers? Also curious about having wing nuts on the back, but hex on the front. Is that for a specific purpose, or just shortage of wing nuts?
 
The spacers are just some plastic things I had. I save everything. No wing nuts in the front because they’re always in the way. The less obstructions the better. Plexi is tapped so I don’t have to mess around with any nuts and bolts to hold work down.
 
There is another way of doing this. The item pictured is a flush-trim router bit. As you can see it has a bearing below the cutting section of the tool. To use it you fix your template beneath the piece you want to shape. The bearing follows the template, and the cutter follows the bearing. These don't generally go below 5mm in diameter but if you want to go smaller you can put a short fixed guide pin on the machine table. This should be exactly on the centre line of the cutter and the same diameter. As before the fixed pin follows the template, and the cutter does the rest. This second method can go as small as the cutters allow. I think it may be a bit more limited than a saw blade when it comes to making very narrow vee-shaped notches but on the other hand way safer than a naked saw-blade.

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Tony P said:
The spacers are just some plastic things I had. I save everything. No wing nuts in the front because they’re always in the way. The less obstructions the better. Plexi is tapped so I don’t have to mess around with any nuts and bolts to hold work down.
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Nice. I’m forced to get rid of stuff due to space limitations, which frustrates me no end because invariably I have a need for something or other I just got rid of.
 
Alan Smith said:
There is another way of doing this. The item pictured is a flush-trim router bit. As you can see it has a bearing below the cutting section of the tool. To use it you fix your template beneath the piece you want to shape. The bearing follows the template, and the cutter follows the bearing. These don't generally go below 5mm in diameter but if you want to go smaller you can put a short fixed guide pin on the machine table. This should be exactly on the centre line of the cutter and the same diameter. As before the fixed pin follows the template, and the cutter does the rest. This second method can go as small as the cutters allow. I think it may be a bit more limited than a saw blade when it comes to making very narrow vee-shaped notches but on the other hand way safer than a naked saw-blade.
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Familiar with these, and even have some, but not going to find many that produce results at the small scale we’re talking about. I’ve heard the concerns about naked blades, and while they are not wrong, I think they may be a bit overblown. It’s when you’re applying lots of pressure to get a tool to do something it doesn’t want to do that risk really starts to amp up. Pay attention, avoid complacency, don’t force things, and you will be fine.
 
Yes bearing router bits would work but they really don't go as small as we need I think. What I'm having trouble visualizing is the actual start and stop point left to right and if I'm making a mirrored image or not. Depending on how the pattern is cut would rectify that. Working on it today again, we'll see the results.
 
Namabiiru said:
I’ve heard the concerns about naked blades, and while they are not wrong, I think they may be a bit overblown. It’s when you’re applying lots of pressure to get a tool to do something it doesn’t want to do that risk really starts to amp up. Pay attention, avoid complacency, don’t force things, and you will be fine
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I spent 20 years working full time as a cabinet-maker and wood machinist so I have seen a couple of accidents and dodged a couple myself. It's when people are rushing or distracted that accidents happen.
 
Alan Smith said:
There is another way of doing this. The item pictured is a flush-trim router bit. As you can see it has a bearing below the cutting section of the tool. To use it you fix your template beneath the piece you want to shape. The bearing follows the template, and the cutter follows the bearing. These don't generally go below 5mm in diameter but if you want to go smaller you can put a short fixed guide pin on the machine table. This should be exactly on the centre line of the cutter and the same diameter. As before the fixed pin follows the template, and the cutter does the rest. This second method can go as small as the cutters allow. I think it may be a bit more limited than a saw blade when it comes to making very narrow vee-shaped notches but on the other hand way safer than a naked saw-blade.

View attachment 491733
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I use these for full scale routing. There's a limit as to how small a cutter diameter you can find (or would be safe) Here's an example from Whiteside - one of the best bit manufacturers. Go to their web site to see if it's useful.


Spiral Flush Trim Up Cut​

1/4"SH, 1/8"CD, 3/8"CL​

RFT1600

​

 
Tony, the potential shortcoming I see with your current set-up is that it’s going to be awfully fiddly trying to work the cross-slide in both axes to follow your pattern closely. I think your carrier needs to be free-floating in one axis using either hand or a spring to fold the guide against the pattern. That way you only have to control the traverse.
 
Namabiiru said:
Tony, the potential shortcoming I see with your current set-up is that it’s going to be awfully fiddly trying to work the cross-slide in both axes to follow your pattern closely. I think your carrier needs to be free-floating in one axis using either hand or a spring to fold the guide against the pattern. That way you only have to control the traverse.
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Oh yes the aluminum bar free to move by hand. I never intended to use the XY table. The clamps you see are holding the work piece to the bar.
 
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Namabiiru said:
Gotcha, but I trust you still have it captured in some way to maintain alignment with the pattern.
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No I don't I'm hoping it can be done by hand. It'll only be used for small parts. There's no way to do that because it has to be moved X and Y at the same time. It will take more jig work for specific parts to be done no doubt.
 
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I was thinking on the problem, and hit on the idea of a 3-piece holder for the work piece. The bottom is attached firmly to the bed and has a dovetail groove or dado running laterally. The second piece sits on that and has a tongue on the bottom that mates to the groove in the first piece so the second can slide laterally. The second piece also has two tongues on the top running transversely (right angle to the tongue on the bottom). The third piece has two grooves on the bottom that mates to to the tongues on the second piece. Your work piece mounts to the third (top) piece. I think this would permit you to easily slide the work piece freely in both axes without permitting it to rotate.
 
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Ok yes. I can picture it. I’ll do some tests. The base board would have to be a couple inches bigger but that’s no big deal. Awaiting delivery of CAF’s La Belle !
 
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