Vacuum forming coil housings.

[lunamay]

hi
i was wonder.. how did you resolve problem with hermetic between frame with plastic and vaccum box .did you use any seal or something like that?..also what should be the number of holes in vaccum box and how big shuld they be..is it important?

best regards
martin

[bernte_one]

hello
you had to put the holes there where you want it gets close to coil
for example the border line of your form
it is not necessary to get it hermetic, the plastic is half liquid when you put it over your form and press on at the vacuum cleaner
more important is the right temperature and one big hole for the vacuum cleaner and not too much little holes the holes they are not needed are closed with tape
to get more vacuum effect at the right points

ps polystyrol works but not thicker than 1,5mm next try i use 1mm it is very stable after hot forming 1mm should be enough and it is cheaper too

[lunamay]

in my country this abs sheet is very expensive..i don't know why..i'm looking for an alternative..maybe buttom of a big bucket for paint (plastic) like 10L or bigger would be good:P

best regards
martin

[bklein]

Go to a (big) company that does packaging solutions for larger companies. They typically use this material to create vacuformed accessory/product packaging pieces for volume shipment boxes and containers. They have huge vacuform ovens that use this plastic in huge roll form. When the material gets near the end of the roll at the end of a product run they often just scrap the remainder. They use the thick clear and black. Maybe the black isn't quite thick enough - not sure. I am friends with head of one of this type company and hope to someday get some material from him to try making coilforms with. Or you could pay them to make you hundreds/thousands of them if you pay for the aluminum tool.... They are willing to make things like RC car bodies that become pretty profitable in retail.

Barry

[bernte_one]

@ lunamay

use polystyrol instead of abs
here abs cost double than polystyrol thats the reason for my experiment

the plastic bottom of a paint bucket is not so good if you meld this plastic it gets holes and it shrinks

[mikebg]

Don, I would like to produce housings for a model differential sensing head. My loop configuration is DOD as shown below.
My question is how to form robust ears for clevis tube? With your former they will be hollow and will have thin walls.

[bernte_one]

strenghten the sensible parts with epoxy and glasfibre
1 liter can 10euro in hardware store in the corner with yacht or boat articles and paints

[taliesin]

tip for fiberglass

strenghten the sensible parts with epoxy and glasfibre
1 liter can 10euro in hardware store in the corner with yacht or boat articles and paints

rub hands and arms with talcum powder to prevent itching ( if you are affected)

[bernte_one]

as little childs i was a joke to jump into glaswool ahh autsch

no imean this for housing

[bernte_one]

Here my first vacu formed coil form:

https://fotoalbum.web.de/gast/bernd....Vacuum_Forming

thx to dfbowers and forum for inspiration

[habitbraker]

Here my first vacu formed coil form:

https://fotoalbum.web.de/gast/bernd....Vacuum_Forming

thx to dfbowers and forum for inspiration

nice! How thick is plastic that you used? What was your form/mold? Which detector is that ?

[bernte_one]

nice! How thick is plastic that you used? What was your form/mold? Which detector is that ?

I used Polystyren best 1,5mm( tried 1mm too but it is critical but possible for coil cover)
the form was cutted by 18mm strong wood plate
this is the surf pi single sided pcb with external battery pack
ond only on off switch all pots are on pcb ( or my little nephew)

[taliesin]

nice work

they look strong lugs.all you need now is "bernte_ one" stickers on there .

[satdaveuk]

nice! How thick is plastic that you used? What was your form/mold? Which detector is that ?

Im I right thinking that the vacum is assembled to the box after its been taken out the oven
I got to talk the mrs round letting me use the oven first.
Ive got a industrial wet dry cylinder vac will that be ok or to powerful?
Thirdly the temperature deflower states is 400f will it melt Lead within the 2 mins its in the oven? or am i pushing the boat out.
The reason why I ask I have skills in sand casting from old, and it would be easy for me to make a lead casting of a 10" DD minelab coil, I cant use alloy etc because I have no means of getting the temp need to melt It, unless you clever folk have a DIY way of doing it.
And I also like to add how greatful and privilaged I am to be part of this team, and once ive sorted my coil maker out which is almost finshed, and got my detector built and up and running , I will able to contribute some more worthwhile information for you all as a big thankyou.
If you were girls i would give you all a nice big wet kiss
Warm regards
Dave

[dfbowers]

Don, I would like to produce housings for a model differential sensing head. My loop configuration is DOD as shown below.
My question is how to form robust ears for clevis tube? With your former they will be hollow and will have thin walls.

Mike,

Yes, the "ears" for the clevis are hollow and have thin walls but once filled with exopy they they become extremely rigid. I have not broken one yet. I sometimes even mix in short strands of fiberglass. It is easy to make them as strong as needed.

I think that might be the way that Hays makes theirs as well.

Don