Modern Vespa

Hi guys,

I'm new to the forum and the Vespa world. Having a bit of a nightmare here since I decided to change the original bag hook with a metal hook instead which involves removal of the glovebox.

Long story short I managed to round off the screw inside the glovebox itself and I need the part number to order a new one. Unfortunately I cannot find it anywhere. If anyone knows this info please share.

Along side this I also removed all other glovebox screws during my attempt. Howver when putting the screws back there lower left and right (longer screw) won't grip on. Is there something extra I have to do in order for it to grip.

I've attached 2 images of the issues above.

Thanks in advance!

Been there, done that, friggin plastics!

I've recovered buggered plastic threads in the past by filling the hole with adhesive and them inserting the screw to full depth loosely. You need to coat the screw with a release agent prior to insertion so it won't stick to the adhesive, a very light coating of oil or grease works.

When the adhesive is hard you carefully rotate the screw out and assemble your parts, being careful to not over tighten the poor thing again.

If the hole is truly ripped out you can fill it in completely with adhesive and drill it to size once its hard. With self tapping plastic screws of the sizes on bodywork, try to find a drill about 0.006 to 0.008 inches smaller than the OD of the screw.

If the plastic post is split vertically fill the crack as well and lightly coat the outside of the post with the adhesive.

2 part epoxy works well for these jobs.

As plant engineer, I used to recover damaged in production automotive lamp assemblies for fun at my last job and got pretty good at this. Seemed worth the effort as the lamps were scrap otherwise and were worth several hundred dollars if salvaged.

Thanks for the speedy reply. I doubt the plastic is damaged in any shape or way and the bike is brand new (3 months old max). I believe something is supposed to be behind it so the screw grips onto, I've done a little more research since posting.

Brand new plastics strip easily if over torqued. When I started at my last job the company was scrapping hundreds of dollars a day in damaged lamps and components because they were still using hand tools for assembly. We had adjustable power drivers put on the production line and purchased a torque meter for setting them up. Even though the screw guns were $1800 a piece and the torque meter about $4000 we paid off the tools in no time in reduced scrap.

Even then, if the screws weren't properly aligned, the plastics not perfect or the guns not maintained properly, the holes could partially or completely strip on assembly. Partially damaged product was difficult to detect and could easily get out the door. I'm pretty sure my own GTS has a few of those.

Working for years in plastic components design and manufacturing I know that self tapping fasteners are not really designed for multiple uses and can strip very easily if disassembled. Their extensive use on the Vespa's bodywork in areas which must be pulled apart for maintenance pisses me off every time I work on it as it is obviously cost savings at the expense of serviceability and longevity.

I would remove everything again to compare that hole with the others to see what is different. Test the screw without the panel on.

1.) Does it catch? If so, is it the right screw for that placement?
2.) Does it slip? If so, try the other screws to see if they catch and try the "bad" screw elsewhere.

If the screw is bad, you can take it to a hardware store to find a workable replacement. If looks is an issue, I'd you can find the same screw size in use from a hidden location to swap with the new, different one.

If the hole is bad, try what suggested Fritz suggested. If you want an easy old woodworkers trick, place a flat toothpick in the hole and then insert the screw. That should hold for a while while you track down a more permanent fix.

I think the other posters have forgotten that these parts aren't held in place by plastic threads. Metal clips (sometimes with machine screw threads, sometimes with a bent piece of metal simulating a thread) straddle plastic tabs, and the fasteners grab onto those.

The clips fall off, rust, and otherwise get lost very easily. I've taken to smearing a dab of R3000 adhesive in the bent part of the clip before reattaching them, so they fall off less easily. Replacements are easily found at Home Depot but are much cheaper by the dozen on Amazon.

They have a variety of names but I think of them as "automotive clips."

Models do vary somewhat and you may be correct. Maybe Yizi will chime in and let us know. I I referenced photos and asked my husband, who's taken ours apart several times, before making my recommendations.

Good point... I'm assuming we're dealing with damaged plastics here, but missing speednuts are a common enough problem. Which is why I keep a package of them on the shelf.

And... no matter how temping it may be... don't use a friggin woodscrew to replace a missing screw into plastic ( or a speednut )
You'll only burst the post in the long run.

One of the problems with plastics is that if the wrong fastener is used the parts may assemble fine and seem solid, but the now overstressed plastics may fail down the road. In only a few days if its acrylic, out to 6 months later if its polycarbonate. There's at least a dozen self tapping screws thread types for plastics and finding the right one can sometimes be a bitch involving a long of longterm destructive testing.

Although.. I must admit... destructive testing was often the highpoint of my workday. Sometimes it was so much fun we had to go outside and test behind a scatter shield, keeping a fire extinguisher handy to boot.

Most of the panels on the Vespa are ABS or alloys of this material, ABS works well when assembled using thread type A or trilobal type screws. McMaster Carr sells these ( and every other screwtype ) off of they're website and deliver in 24 hours as a rule. Expect to have to buy a pack of 25 or so and you may have to find a way to up you order to 25 bucks... but there's so much useful shit on that site that I never found that a problem. Back when they issued a paper catalogue it was over 2000 pages!

Also known as Tinnerman Nuts.

Never used the website below but it has good illustration of what types are available:

https://www.fastenersuperstore.com/category/tinnerman-style-nuts

Chris from CLE

for the screw in the glovebox, maybe you can pound a torx bit into it and ease it out, otherwise you're looking at a removal tool or drilling it and extracting. which, ugh. on the other one, I think it's probably just hung up, or more likely, it's just spun in the fastener and you can pull it all out and replace.

good luck!

Quick update for everyone just in case someone else has this issue. I ended up going to the garage and they checked the screw which was rounded (it was a T30 and and not T25 like the remaining screws! That teaches me to try work in day light and not with a torch)

Now regarding the two longer screw at the lower part of the glove box. They have a little metal clips behind the plastic which the screw holds onto. When I opened the screw and took it out they dropped out! Not the best design and the only way you can put them back is to take part of the floor panel and place them back on.

Thanks everyone for the help!

Make sure you get them the correct way round. The longer screw goes on the outside and the shorter screw goes on the inside as there are rubber hose pipes behind the glove box which can get punctured.