Jump to content

How to Precisely place PE


Recommended Posts

Can you suggest a manner in which I can precisely place tiny PE items on the model.

 

I've tried ... 

1. a droplet of water, or just moisten the PE, to keep it in place until I CA it ... nope, it moved

2. I tried a droplet of paint to keep the PE in one place till I CA it ... that sort of worked. But the PE item was just off level by an RCH.

3. these tiny PE pieces are too small to use tape

 

Any suggestions gents?

 

Here's an image of the PE and where I wanna place 'em ... on a curves surface

 

Tips for PE.JPG

Link to post
Share on other sites

get a post-it or similar little piece of paper with straight edges

 

temp. place the pe parts onto their locations and secure em via something sharp or pointy, like a blade or syringe (tinier the better)

 

get your ca glue onto some flat surface then wet the post-it/paper letting it soak the glue evenly overall. depending on the shape of the surface area you may want to bend the edge or a corner of the paper into an L shape here!

 

use the paper as a glue applicator, slide it in-between the part and the surface! if your ca is not of a lightning fast drying type then you should have ample time to work those tiny parts. also understand since you are holding/pressing the part down from one end it can not be entirely glued, but just wait for the ca glued section to cure, then repeat for the opposite end and it should be easier this time since the part is half stuck and hanging on it's own already. 

 

alternatively if the surface is plastic you can initially "soften" the area with extra thin cement, making it tacky enough for the pe to grab, then work again with ca as well. however this won't work on any other surface since extra thin can only work ps and nothing else.

Edited by murad
.
Link to post
Share on other sites

Mold the PE to the surface shape. Ideally against the plastic surface but you may need some other object to make the PE shape more consistent with its destination. 

 

Then, as @muradsuggested, pin it down with a pointy object in one hand while you apply CA with an applicator in the other hand. Paper is fine as an applicator but I prefer a metal tip for a knife handle, like these from RB Productions.

Link to post
Share on other sites

The gel glue is too thick for those tiny parts, it will just make a mess of things. I use the gel CA for filling gaps.

You need to purchase some "fresh" CA so it will flow. I use 34 gauge wire to apply my liquid CA. I cut a length of wire @2 inches long and put a little bend on the end (this resembles a hockey stick with a straight blade). I use chunks of clay from the craft store to hold my puddle of CA. I make a small indentation in the clay with the end of an X-ACTO knife, add my liquid CA and, dip my wire in the puddle and apply that way and let it flow. When the end of the wire gets too much glue on it, I simply cut the end with some sharp wire cutters and start over.

Hope this helps.

 

Steve

Link to post
Share on other sites

Thanx guys ... but no joy yet.

A-10 Loader, that's exactly my technique. But when my wire loop gets clogged, I hold it over a lighter and burn off the dried up stuff.

The CA I use bonds instantly which is why I need to place it ex-act-ly.

 

If you look at my image, those little circles at the top of the fret, will be cut off  and THOSE need to be applied. A sharp point won't be fine enough. Like I said these are ti-i-iny-y-y parts and they have to go on pre-cise-ly.

 

So my question is ... how do I hold those itty bitty bits onto my surface prior to gluing? I'm just looking for a real temporary solution so I can adjust the position of the PE and then instantly adhere it. The Gel, which I have, will just ooze out of the part ... that's not acceptable.

 

Man ... I hate tiny PE parts!  :whistle:

 

Thanx gents!

Edited by K2Pete
spelling .. darn auto-correct!
Link to post
Share on other sites

Thanx viper730 ... 'twas an interesting read. My first thought is "it may be too thick." I mean, even CA, applied with a small applicator, leaves a droplet that is too big.

 

Now, I'm not looking at replacing the glue, CA works fine, I'm just wondering how to place it, remember these parts, disks, are about 1 mm in diameter and I just want to hold 'em, precisely in place, while I apply the CA.

 

Hm-m-m-m ... Future eh? ... now THAT sounds like a good idea! ... Many Thanx cag_200! I'll hafta try this out and I hope the CA displaces the Klear ( Future )

 

Thanx guys!

Edited by K2Pete
added a response
Link to post
Share on other sites

That was IT!! Thanx guys!   :thumbsup:

 

When I started modelling about 12 years ago, I pored over all the modelling sites looking for tips and tricks ... one of 'em was that Future can adhere delicate parts or clear parts. The bond isn't super strong, but it's strong enough. And as I read cag_200's suggestion ... it dawned on me that I had indeed used this technique many years ago and simply ... forgot it!

 

Thanx alot for your suggestions gents! 

Pete

Link to post
Share on other sites

I use clear gloss acrylic lacquer as an adhesive.  You can buy a giant spray can of it at most auto parts stores.  Decant a little into a cup of some sort.  Then apply the lacquer with a paint brush to the PE part where you would normally use CA. The lacquer takes a few minutes to dry so you can use it as an adhesive directly to the plastic, and have some work time to move the part.  If you mess up, be ready with some 91% isopropyl alcohol to clean up the plastic, and PE part.  Conversely, you can apply the lacquer to the plastic part then press the PE part to it.  It really depends on the parts used, and where they are on the model, as to which method will be better.

 

Alternatively, You can let the lacquer dry on the PE.  Once the lacquer dries, it basically becomes a layer of plastic.  Now you can use regular MEK type liquid cement to attach the PE part to the plastic part of your model. You can tack things in place this way and it makes a strong bond on its own.  However, once glued down with MEK, you can use very thin CA, along with capillary action, to wick an added bond with the CA. Just makes sure you let the lacquer and/or MEK dry for 24 hours before you apply the CA.  Otherwise you may seal the still soft lacquer/MEK under the part with no way for the volitols to escape.  Think of the CA as putting a microscopic layer of caulk around the PE part.  You want the Lacquer/MEK bond to have full strength before you apply the CA.  Now you have two strong bonds holding the part.

 

 I make my own CA applications out of a single 5 inch very thin piece of wire pulled out from the inside of a scrap electrical wire. The thinner the better.  Bend it around the end of a tooth pick or needle, then twist the two ends down to the tooth pick, then slide the loop off of the toothpick. The toothpick or needle can give you different diameter loops, depending on where you make the loop.  At the point, you can make a tiny loop, further down, you can make a larger loop. What you are trying to make is a tiny loop at the end of a stem.  Like a very tiny lollipop.  This loop and stem can be glued to a toothpick to act as a handle.  This tiny loop can be dipped into a drop of extra thin CA.  The loop is then just touched to the joint between the PE and plastic.  Capillary action pulls the CA along and under the joint to bond the two pieces.  I keep a tea candle burning within reach so that after each application, I can pass the loop through the flame to burn off any CA that may have cured on the loop.  The loop needs to be clean so that the capillary action works better.  Use small loops and don't try to apply too much at once.  Just wick some CA in there and let it cure.  Then if you need more, add more.  When you put some extra thin CA into a container to dip your loop into, only put in a few drops.  As that CA starts to dry in the container, it get thicker and loses some flow for the capillary action.  One or two drops at at time, and as many trips to the models as you can make in less that 3 or 4 minutes.  Then you need fresh CA.  I make a half dozen applicators at a time, and my loops are usually no more than 1/16" in diameter or less.  The repeated burning of the CA in the candle will weaken the wire and eventually it will break or crumble.  I also make a few applicator that are "U" shaped.  Make the loop as stated above then cut the loop oposite from the "handle" with a razor blade.  Carefully shape it into a narrow "U".  On some parts/joints, this works a little better.  

 

For larger flat PE parts, mask off the areas you don't want the lacquer on, and spray it directly onto the PE part.  Let it dry for about 30 minutes, then use the MEK and CA as described above.  Always rough up the PE part surface with a swipe or two of 600 grit sand paper. It helps the lacquer and CA "bite" onto the PE part.  If practical, it also helps to do the same on the plastic surface, if you can avoid sanding away any precious molded in detail.

 

The lacquer dries to the touch quickly, but I have found it really takes about 24 hours to dry between parts.  It is a "paint" product, and the volitols need to off-gas for it to fully harden.  When it is sandwiched between two parts, there is not a lot of space for the volitols to escape. So be patient.  On it's own, the lacquer makes a nice strong bond that is not as rigid as CA, and won't snap off as easily if the part has some side force applied to it.  However, I do recommend the combination of CA as described above.  If the model allows for it, meaning there is no risk of getting CA where you do not want it, then make a combination joint of lacquer and CA.

 

If you have any scrap model parts and leftover PE parts, practice with these first before going to your current project.  The applicators work great, but you need some practice to get the "feel' of the process and the qualities of the Acrylic lacquer.

 

These same techniques can be used to glue brass to brass.  To use the MEK method, just apply the lacquer to both surfaces first and let dry before using the MEK..  Or simply apply some lacquer to one part and bring the two pieces together while the lacquer is still "wet".

Edited by James B
Link to post
Share on other sites
On 8/14/2019 at 11:59 AM, K2Pete said:

Can you suggest a manner in which I can precisely place tiny PE items on the model.

 

I've tried ... 

1. a droplet of water, or just moisten the PE, to keep it in place until I CA it ... nope, it moved

2. I tried a droplet of paint to keep the PE in one place till I CA it ... that sort of worked. But the PE item was just off level by an RCH.

3. these tiny PE pieces are too small to use tape

 

Any suggestions gents?

 

 

Maybe like this, with Blu Tack blobs:

 

rq7-03.jpg

 

Just be sure to avoid CA from flowing under the Blu Tack too.

 

Rob

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...