Plastic Binding Gaps

[Clancy]

Never used plastic binding before.
Normally use wood & hide glue!
Wish I did this time too.

So what's the best way to deal with gaps in plastic binding?
In this case it's black so should I....
...fill the gaps with ebony dust & CA?
...fill the gaps with plastic filings & melt with acetone?
...use more WeldOn in the gap to melt the plastic a bit & force the gap closed?
...???

Cheers

[Kim]

I find plastic OK to work with Craig and never had to fill, but I would imagine CA would do the trick depending on where the gaps are...you would know that unsealed endgrain spruce will suck it right up and stain yellow. Anyhow its worth knowing in case you didn't that plastic bindings swell up when first glued, so it is important to wait a few days to let them gas off any thinners from the glue and return to their original size 'before' you even thing about scrapping them back.

Cheers

Kim

[Clancy]

wait a few days to let them gas off any thinners from the glue

Didn't know that. Makes sense. Thanks Kim.

[Kim]

wait a few days to let them gas off any thinners from the glue

Didn't know that. Makes sense. Thanks Kim.

Glad you got something from it Craig. As for fill? After a bit of thought I reckon I would go with epoxy. You can add fine ebony dust (use a fine bastard of a file to avoid contaminants) and to help things along a bit, add a bit of compatable black tint, better yet, pigment. Together they should fill the voids nicely, scrape back level at a similar rate to the plastic, and avoid the dreaded gray giveup.

Cheers

Kim

[Dominic]

Can you put a few drops of black dye/stain in the weld-on. BTW, where did you get it?
Dom

[Skip]

I think epoxy putty would work pretty nice. Easily dyed and neat to work with, dries hard enough to get it to a nice shiny finish.

[tippie53]

Here are the issues
When filling gaps , often CA may react with one of the woods , On spruce it can often turn yellow . This may not happen for a while but shows as a stain. On other woods like Walnut and Mahogany the CA wicks deep into the grain and shows as a light spot. You may need to look at your technique on binding. More often than not wood will gap and not plastic. I use stretch tape and a roller to be sure the binding is well seated.
Ok so you have a gap , well this happens to all of us once in a while. It isn't that we may not see them , it is how we hide them. If the gap is sever enough I may redo the binding. Depending on the plastic you may be able to melt is down with acetone and drop fill. If this isn't an option then you have to look at filling with dust. Here is where I have used a few tricks I learned. Often glue and dust will make a nice putty and be fine however when staining or finishing the "putty" will show because the glue seals the wood from accepting the stain and will appear different under clear finish.
What I find that does the best job for me is to make some fine dust from the wood I wish to fill and then drop thinned finish or shellac on it. If I plan on staining I may wait until that part of the process , drop in the dust right after the staining and stain the dust , then drop fill with shellac that is thinned . Allow an hour and hit that will full shellac of sealer. Once the area is well sealed , then I may drop fill with finish or CA depending on the situation. This allows the filled area to have the same color and you won't have that glue print under the finish as the wood dust has color. Test this a few times and you will soon master the technique .

[Clancy]

Thanks everyone. Much appreciated.

As I said, I have always used wooden bindings, and have successfully filled gaps (in the early years) but now use hide glue & simply re-heat & re-work the area of 'non-conformity'

But this is the first time I've used plastic binding (apart from f-holes)
Somehow this time I ended up with a less than perfect job.
I had thought that the binding went into the channel well, and I used green tape to hold it in place.
Maybe I didn't see the gaps because the binding is black, my eyesight has certainly deteriorated in recent years.

Got flu at the moment, so I'll dwell on it for a while before chosing an action.

Thanks again.

[Clancy]

Sorry Dom. Got the WeldOn at ACT Plastics in Lyell St Fyshwick.

[Clancy]

So I sorted the gaps.
On the top & back joins I drizzled WeldOn in to the gap, gave it a minute to melt the binding a bit, then forced the gap closed & taped.
On the sides I filled the gaps with ebony dust & CA.

Now onto the next new experience with plastic - to what degree do you sand them?
I have been surprised at how soft the plastic is to 'work'.
General sanding leaves deep scratches.
Any sanding, even with 600 grit, leaves the plastic looking like shit!
Will this dissappear under a finish (shellac in this case) or do you 'finish' up the preparation by doing a final scraping of the bindings?

Looking forward to putting these plastic things behind me & returning to wood

Cheers

[Nick]

I usually scrape any bindings Craig but especially Plastic, you end up with a nice smooth,even finish & I've found it's quicker at leveling the bindings too. Just don't scrape in one small area for too long, the heat build up is remarkably quick & it can do strange things to the plastic (don't ask me how I know )

[Kim]

I usually scrape any bindings Craig but especially Plastic, you end up with a nice smooth,even finish & I've found it's quicker at leveling the bindings too.

+1

[Dominic]

I'm just about to put plastic binding on two of those CS336's I made so I'll soon find out but.... A little plane worked good last time and is less likely to dig in than a scaper on the top. Scraper on the sides.
Cheers
Dom

[Clancy]

I've already scraped the bindings flush, but in preparation for the finish I sand the top, back & sides up to around 300 grit.
This is when the bindings have gotten scratched.
I'll have to try lightly re-scraping the bindings after I've sanded.
What a PITA this plastic stuff is.