Might be able to find a different Dremel head designed for plastic?
1 Like
Another mistake is believing the can’s drying and curing time. Even in Texas heat the cure time takes way longer than they state on the can for full strength. testing it with your finger nail in an area you won’t see normally will give a good indicator on if it cured or not.
Give it a week before doing anything on the deck to avoid denting the finish.
How soft is the plastic? if it is on the softer side you can use an exacto knife and carefully cut it out. It’ll require you to cut in the same spot multiple times. You want long continuous cuts where possible and plenty of blades. Buy the blades on amazon and not in store or else you’ll grossly over pay. Switch to new blades often so get at least a 40 pack
Using a straight metal edge will help keep the cuts clean and straight for the straight sections. I use a giant completely metal ruler with my exacto knife
You want this style of knife:
Alternatively, use a metal cutting disk on the dremel and a low speed. Higher speeds are where I noticed the plastic starting to burn when using one. Downside is it’ll take forever.\
An exacto knife will work on harder plastics too but it is just a pain in the ass to do it that way since you have to cut the same line over and over and over again
id probably avoid trying to cut the final shape directy with something like a dremel. maybe try cutting it to rough shape but leaving everything a bit proud of where it needs to end up. Then leave the wood guide bolted on and use a file to bring the piece to final size. This would make it very hard to make any serious mistakes since it is very hard to do any serious damage quickly with a file but this also means it could take a while. Depending the file you use, this could be quite quick or very slow. I’ve never used abrasives on delrin but i doubt doing so would pose any issues in a general sense.
idk just a thought.
1 Like
That’s a good idea, I’ll try that
I tryed cutting it with a knife, it’s a no go, hardly do anything
1 Like
Is there such a thing ?
1 Like
Definitely exists, although I can’t attest to the effectiveness
Dremel EZ476 1 1/2-Inch EZ Lock Rotary Tool Cut-Off Wheels For Plastic - 5 pack https://a.co/d/ebCm1IP
Ah, yeah I don’t think it’s a problem to cut it with a disk, I was tryimg to route it with a bit like that
3 Likes
I used the disks made for metal and then clean it up with a sand disk or what you used to cut it originally. for abs
So I tryed all of the above:
all of the bits I tryed were melting the plastic
the disk worked but it was loud as hell and I had pitty for my neighbours (I get back from work late and almost never start hobby things before midnight) also it still need a good bit of filing afterward
Starting from a chunck and using a file all the way through works, but well every time I tryed I was interrupted by colorfull flashback of rock-lee sensei explaing that I should not waste my better years and the fire of my youth doing this kind of things
option 1) trying to temporary dye it dark so I could laser-cut it ? not sure you can dye delrin and not sure you can get it back to white afterward
option 2) using some junk motor and esc to build some kind of belt sander
option 3) harassing the woodworker nextdoor until he lets me using his cnc
option 4) maybe I can thermal-cut it somehow, I need to try
1 Like
Coping saw might work, cut outside the lines and sand it flush?
1 Like
So thermal cutting works,
It’s not perfect jet but it’s the best I got so far, maybe I can build a hot wire rig somehow
1 Like
I’m back from holidays and w’re back at it !
- I got some guitare strings to put up an home made hot-wire cutter
- todays’ task is to modelise the deck complex concave shape of the deck so I can start working on the enclosure itself
1 Like
Started modelling the enclosure and all, here is a little mathematic riddle for you nerds : 
One cells has a diameter of 21mm
The minimum width of the enclosure is 225mm
I want to feet 12 cells parallel to the deck
How do I calculate the angle between each cells using only algeabrae and not geometrie ?
Here is what I did, geometrically, it’s good enough to work with but I’d have loved to find a more mathematical approach :
225 - 21 (that is half the diameter on both side) = 204
204 / 11 = 18.5454 Which is the string at contact point between each circle
and then it’s geometrically immediate to feet them, and I can measure the angle
Yeah your logic is correct. 18.5454 is the length of that bottom edge, which is 21*cos of the angle. So the angle is just arccos(18.5454/21) = 28 degrees
Yeah but still, how to do it from the start without using cad trick ? only with nymbers
Usually it’s easiest to solve geometry problems with geometry 
And thanks to it you discovered the formula!
L = total length available
n = number of cells
d = cell diameter
angle = arccos((L - d)/(n - 1)/d) 
P.S. I would suggest wrapping the ends of the cells with fishpaper and then measuring the diameter, and using that / the middle of the two numbers if you only go with a single layer.
1 Like
Sure, I still haven’t got the cells on hand, I’ just trying to get and idea of the internal management of the enclosure
