Six pieces of thick acrylic cut and drilled ?

[Al (astral highway)]

Is it within forum rules to ask for a request like this here?

I’m looking for someone who has access to acrylic /or even better , a heatproof dialectric about 1cm thick who will be able to

: cut some matching pieces, drill holes to a spec, cut in half so holes are halved and polish all sides. It means the halved drill holes will be uppermost.

The approx dimensions (to see if this is manageable) are 125 mm long pieces. -*Details will be confirmed clearly to the interested party.*

Mods please move if this is the wrong section.

I will obviously pay a fee dodger work , materials plus packing and postage

Thanks folks .

[Ed_Dinning]

Hi Al, have a look at the material details , especially dielectric constants and losses for the frequencies you will be using or it may get a bit hotter than you think.

Ed

[Radio Wrangler]

If you drill a hole and then cut the material in two, you can't get a halved hole. You'll be out by half the saw thickness on each part... plus a polishing allowance. If it's critical you my have to make two pieces, drill two holes and cut offset to leave one halved hole, and one piece of scrap.

Standard engineering question; What accuracy do you require?

David

[Al (astral highway)]

Originally Posted by Ed_Dinning

have a look at the material details , especially dielectric constants and losses for the frequencies you will be using

thanks Ed, I’ll bear that in mind .

[Al (astral highway)]

Originally Posted by Radio Wrangler

If you drill a hole and then cut the material in two, you can't get a halved hole. You'll be out by half the saw thickness on each part...

Hi David , yes , I had conceptualised that but was thinking the millimetre or so loss from sawing wouldn’t matter.

A 10mm copper tube needs to be clamped from underneath and in fact it’s ideal if the clamp doesn’t take up half its circumference. It doesn’t matter that the copper will be slightly more proud of the clamping body.

Originally Posted by Radio Wrangler

what accuracy do you require ?

Plus or minus 10%. If it’s minus, it gives me some work to do.

[Station X]

Could you use off the shelf tube clamps? They come in various forms of which this is one.

https://www.ebay.co.uk/itm/Tube-Clam...-/162072521478

[David G4EBT]

For the avoidance of doubt, if you are intending to use 10mm copper plumbing tube (ie, 10mm microbore, which is usually half-hard annealed and comes coiled up - not in straight lengths), as with all plumbing copper tube, it does refer to the outside diameter - not the bore, so you'd be OK in that regard. (10mm annealed tube has 0.8mm wall thickness - hard drawn tube is 0.5mm wall thickness).

https://www.engineeringtoolbox.com/c...sure-d_20.html

If you want hard-drawn 10mm OD straight copper tube you may have to search for it. Most suppliers who supply short straight lengths of 10mm OD copper tube will state that it is 'off the coil', which I guess will be fine for your needs as you're only using 75mm lengths and well supported.

Good luck with your project Al.

[Al (astral highway)]

Originally Posted by Station X

Could you use off the shelf tube clamps

Great idea, although I’d have to stagger the supports. Also I’d need to look up what temp polypropylene can deal with.

But kudos to you for your ingenuity, knowledge of materials and ability to come up with a creative solution!

[Al (astral highway)]

Originally Posted by David G4EBT

For the avoidance of doubt, if you are intending to use 10mm copper plumbing tube (ie, 10mm microbore, which is usually half-hard annealed and comes coiled up - not in straight lengths), as with all plumbing copper tube, it does refer to the outside diameter - not the bore, so you'd be OK in that regard.

Good luck with your project Al.

Hello David,

Very relevant and clear, thanks.

The loose spiral coil of 10mm O.D microbore has arrived , with its distinctive golden hue which must arise during the annealing process. )

For context , it’s about 5m long and will form an inductor using the entire length . I just need to form it into the correct geometry, with the spaces between turn the same as the OD.

As with many of these things, for me, the challenge is around managing materials in the simplest way. Here, good looks are also important .


Cheers !

[Malcolm G6ANZ]

When I needed some perspex to make electron trees I used this company:
https://www.perspexsheet.uk/?-kSRvGw...MaAi_4EALw_wcB
They may be able to help.

Malcolm

[Al (astral highway)]

Hi Malcolm,

Thanks , that’s a useful resource and I’ve ordered!