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moldingppm
16th October 2013, 09:52 PM
I have a job running HIPS, the piece that is stuck is about .100"W x .100"H x .250"Deep inside the mold/cavity and it's a "U" Shape. I started up this mold only to find that I didn't remove it last time this job was ran, so what would be the best way to remove this? It's an alum mold, so I'm afraid to make any harsh moves. How about an oven? I've used a soldering iron with no luck so I'm stuck at this point.

Suhas
17th October 2013, 04:11 AM
Can you shoot another shot over and see if it will pull out? Be careful if you are going to try it. Use low speeds and pressures, may be slightly higher melt and mold temps. Make sure the plastic in that area has solidified but not very cold before you pull out the part - slowly.
Regards,
Suhas

moldingppm
17th October 2013, 05:27 AM
Can you shoot another shot over and see if it will pull out? Be careful if you are going to try it. Use low speeds and pressures, may be slightly higher melt and mold temps. Make sure the plastic in that area has solidified but not very cold before you pull out the part - slowly.
Regards,
Suhas

That's usually what I do. Usually run a second shot, extend the cooling time 3-4x and open the mold slowly. Nothing. I'm figuring there are burrs keeping it in there. I need to check it and polish when it's cleared out...

rickbatey
17th October 2013, 12:25 PM
Get out your hot melt gloves and purge a fairly large lump of resin. Place the blob onto the part/mold then close in set up squeezing the mass as much as possible. Then wait for it all to cool enough to eject.
Only other chance is to use a hot air Lazor or chemical to set the HIPS in heat and break it down.
Rick.

brentb
17th October 2013, 04:30 PM
Another (the others are great) is to place toilet paper (not Charmin) over the cavity with the part and clamp up ( make sure it is safe as far as molding surfaces getting damaged) clamp up and slowly open. Sometimes pulls out part.

Keep on Molding!

brent

brentb
17th October 2013, 04:31 PM
Can you shoot another shot over and see if it will pull out? Be careful if you are going to try it. Use low speeds and pressures, may be slightly higher melt and mold temps. Make sure the plastic in that area has solidified but not very cold before you pull out the part - slowly.
Regards,
Suhas

Maybe soften the HIPS part with a heat gun or a bit with a propane torch before doing above?

KOM

brent

moldingppm
18th October 2013, 12:50 AM
Maybe soften the HIPS part with a heat gun or a bit with a propane torch before doing above?

KOM

brent

Tried that, didn't work.


Another (the others are great) is to place toilet paper (not Charmin) over the cavity with the part and clamp up ( make sure it is safe as far as molding surfaces getting damaged) clamp up and slowly open. Sometimes pulls out part.

Keep on Molding!

brent

Care to shed some light on this? I've never heard of doing that...


Get out your hot melt gloves and purge a fairly large lump of resin. Place the blob onto the part/mold then close in set up squeezing the mass as much as possible. Then wait for it all to cool enough to eject.
Only other chance is to use a hot air Lazor or chemical to set the HIPS in heat and break it down.
Rick.

That's what my last option is, but I'm sure if I try running a cycle and it doesn't work, doing a hot melt won't work.


I'd hate to be getting out the good old drill and mini bits...

Chris
18th October 2013, 05:53 PM
I'd hate to be getting out the good old drill and mini bits...

I would never do that, is there enough room to smash some screws flat or use paper clips to heat up and melt into it ?

Spray it heavily with mold release and pull out.

Chris

moldingppm
18th October 2013, 07:24 PM
I would never do that, is there enough room to smash some screws flat or use paper clips to heat up and melt into it ?

Spray it heavily with mold release and pull out.

Chris


Yeah, I'm not too keen on doing it either. I didn't think about the paper clip, Let me try and get back to you guys,
Thanks!

Mitchell

Chris
18th October 2013, 07:45 PM
yea, take the end and squeeze it so there is about 1/4 of an inch, heat that baby up, almost glowing and eaze it into the plastic, then spray that sucker with mold release. it may not work the first time, but eventually after loosening it up and taking some plastic out, it will eventually come out.

moldingppm
18th October 2013, 08:51 PM
yea, take the end and squeeze it so there is about 1/4 of an inch, heat that baby up, almost glowing and eaze it into the plastic, then spray that sucker with mold release. it may not work the first time, but eventually after loosening it up and taking some plastic out, it will eventually come out.

Squeeze it in a hook shape? That should work. I'll run out and try it now.

moldingppm
19th October 2013, 01:26 AM
Welp, I tried the paperclip method, and the broke inside the mold...

Chris
21st October 2013, 04:59 PM
Time to squish down some brass screws.

brentb
22nd October 2013, 05:08 PM
yea, take the end and squeeze it so there is about 1/4 of an inch, heat that baby up, almost glowing and eaze it into the plastic, then spray that sucker with mold release. it may not work the first time, but eventually after loosening it up and taking some plastic out, it will eventually come out.
The mold release cools it quickly!

brentb
22nd October 2013, 05:09 PM
I have a job running HIPS, the piece that is stuck is about .100"W x .100"H x .250"Deep inside the mold/cavity and it's a "U" Shape. I started up this mold only to find that I didn't remove it last time this job was ran, so what would be the best way to remove this? It's an alum mold, so I'm afraid to make any harsh moves. How about an oven? I've used a soldering iron with no luck so I'm stuck at this point.
Did you get it out?

kelly c
23rd October 2013, 12:46 AM
I know I am late to the problem..But..I always use small hobby saws..they got the teeth..are hard..and you can find all types of sizes..thin thick long short...or band saw blades..hack saw..and so forth...I just break them to the size I need...
then of course get them glowing red..with a torch..And have plenty of Mold release ..for the cool off..!!
Then a pair of side cutters to pull with..dont rush..Patience is a true virtue when using this method.!

I work with aluminum tooling 95% of the time..and some small scratches can be removed with a nail file from your local beauty shop ..LOL !!
Hope this helps in the future !.... Keep on Molding !

moldingppm
23rd October 2013, 04:11 PM
Thanks for the ideas everyone.

Nope, I ended up pulling the job to put another in. Luckily, this job isn't ordered yet, I was just trying to run some stock. Looks like I've got another project on the good old mold table...

rickbatey
24th October 2013, 03:43 AM
BTW-I teach all I train to grind off the teeth on hacksaw blades since they tend to be made of carbide and damage molds! If you need something to lock the rib to the blade grind some notches into the blade. I don't use mold release as I see it as a huge waste of money! Just compressed air.
Rick.

Chris
24th October 2013, 06:19 PM
BTW-I teach all I train to grind off the teeth on hacksaw blades since they tend to be made of carbide and damage molds! If you need something to lock the rib to the blade grind some notches into the blade. I don't use mold release as I see it as a huge waste of money! Just compressed air.
Rick.
I like to think the mold release as a lubricant, it may get back into different spots when there is a melted area and help the part to come out ?

brentb
25th October 2013, 06:09 PM
BTW-I teach all I train to grind off the teeth on hacksaw blades since they tend to be made of carbide and damage molds! If you need something to lock the rib to the blade grind some notches into the blade. I don't use mold release as I see it as a huge waste of money! Just compressed air.
Rick.
Rick,
Stuck parts waste money and compressed air ain't cheap!
keep on molding!