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General => Cosmetic and bodywork matters => Topic started by: LowlifeDubber on 03 February 2011, 21:04

Title: Plastic welding advice.
Post by: LowlifeDubber on 03 February 2011, 21:04
Ayup.
Im just about to embark on my 1st stint at plastic welding.Cutting a MK4 Golf recess into a MK3 Golf rear bumper.
I was looking at different plastic welders on fleabay and then a mate said he had a basic one.
(http://www.machinemart.co.uk/images/library/product/large/04/040215340.jpg)

I think this will be alright for tacking it up but not for doing a proper job.
Ive seen these on ebay.

http://cgi.ebay.co.uk/1080W-Plastic-Welding-Welder-Hot-Air-Gun-/170595883731?pt=UK_Home_Garden_PowerTools_SM&hash=item27b84e9ad3

http://cgi.ebay.co.uk/1500W-Plastic-Hot-Air-Welder-Fast-Welding-Kit-Sp-Heater-/190497850109?pt=UK_Home_Garden_PowerTools_SM&hash=item2c5a8e82fd

Or am i better off getting a hot air gun and buying a speed welding nozzle seperate?
(http://www.machinemart.co.uk/images/library/product/large/06/060815002.jpg)

Also, is there anything i need to take into account before i start welding(like what type of rods i need?Do i need to clean the prepped area with a solvent 1st?

Any help would be great.
Thanks
Title: Re: Plastic welding advice.
Post by: thai-wronghorse on 03 February 2011, 22:14
BUMP - Id like to know some more about plastic welding as well.
Title: Re: Plastic welding advice.
Post by: MrAnderson93 on 04 February 2011, 00:12
ive plastic welded my bumpers, i used a bog standard soldering iron  :drool:

i smoothed the front bumper, i used blanks cut from a spare rear bumper and i made my own rods from the rear bumper lol (hopefully you have a complete mk4 golf bumper to make your welding rods from)

its pretty simple, just make sure the reccess piece is about 3mm widert than the hole on the mk3 bumper,then you can use that excess plastic to weld and melt into the mk3 bumper, use the rods then to add strength and fill in places.

after that simply smooth the plastic welds, fill prime and paint  :smiley:

ive even had a crash, bumper bent and the filler cracked but my welds stayed strong :P so you got no worries with strength

hope this helps
Title: Re: Plastic welding advice.
Post by: LowlifeDubber on 04 February 2011, 07:19
Great stuff.Thanks for that.Will be tackling it today :)
Title: Re: Plastic welding advice.
Post by: badboybunty on 18 February 2011, 16:43
try wurth re-plast as plastic welding aint much good anymore u only achieve 60% of origanal strengh but with re plast 90% and is strong as anything u can hang of the bumper and it wont snap

but is mighty expensive tho  :cry:

http://www.wurth.co.uk/catalogue/pdfs/UK-CD_05_0685.pdf
Title: Re: Plastic welding advice.
Post by: thai-wronghorse on 18 February 2011, 17:09
http://www.performancemotorcare.com/acatalog/Wurth_Replast_Plastic_Repair_Kit.html
Title: Re: Plastic welding advice.
Post by: Tazzy on 19 February 2011, 11:39
just make sure you weld all the way along, not just tacks, both sides as well if possible, its time consuming but you know itll stay strong

a mate and icut his rear puma bumper in half and extended it 6 inches, as well as shortened the number plate recess by 8 inches, looked mint!
Title: Re: Plastic welding advice.
Post by: LowlifeDubber on 03 March 2011, 22:01
Here we go,welded both sides,sanded down,refilled,sanded down,rewelded(repeat to boredom) :evil:

Then plastic filler and plastic primer agogo.
(http://img696.imageshack.us/img696/6756/img0028xsm.jpg)
(http://img687.imageshack.us/img687/3197/img0029pp.jpg)
(http://img146.imageshack.us/img146/9829/img0031dw.jpg)
(http://img135.imageshack.us/img135/6411/img0034sf.jpg)
(http://img824.imageshack.us/img824/6906/img0035rsv.jpg)
(http://img268.imageshack.us/img268/1702/img0042ynr.jpg)
(http://img138.imageshack.us/img138/8499/sta70266.jpg)
(http://img580.imageshack.us/img580/2963/sta70267.jpg)
(http://img232.imageshack.us/img232/7682/sta70262.jpg)
(http://img132.imageshack.us/img132/7406/sta70263.jpg)
Title: Re: Plastic welding advice.
Post by: tweed on 19 March 2011, 13:11
Good effort dude!!
but I think smooth mk3 boots look  :sick:
I want to plastic weld us spec rear valance to my bumper
Title: Re: Plastic welding advice.
Post by: shepgti on 19 March 2011, 15:17
nice work on that mate, how easy did you find the process?
Title: Re: Plastic welding advice.
Post by: LowlifeDubber on 19 March 2011, 17:19
Cheers lads.
The process itself was easy,very easy intact.it was just very time consuming,I wanted as little filler in there as poss so every pin prick I found I dug it out and refilled with plastic.
Maybe I'm a little anal but it took about 20 hours in total.
I'm guessing a bodyshop could do it in a quarter of the time but it was my first go and I didn't want to mess it up ha ha
I am actually wishing I did put a us tub in now but I will be reworking the front bumper to take an intercooler in a few months so may do another rear one while I'm at it.
Title: Re: Plastic welding advice.
Post by: shepgti on 19 March 2011, 17:26
im sure you could sell that bumper youve made anyway :wink:
Title: Re: Plastic welding advice.
Post by: LowlifeDubber on 19 March 2011, 17:32
Yeah I'd like to think I could get £40/50 for it.but I need to source a us mk4 bumper 1st.oh and then upset my sprayer with a handful of bits to paint again ha ha
Title: Re: Plastic welding advice.
Post by: shepgti on 20 March 2011, 00:57
how much did you pay for the tool in the end as i may be modding some bumpers in the near future
Title: Re: Plastic welding advice.
Post by: LowlifeDubber on 20 March 2011, 09:17
I actualy borrowed a mates.The 1st picture in the 1st post shows a link to a soldering iron and soldering gun set up from machinemart.Its £17.99 for the whole kit and its a bloody bargain!
I used the gun with no problems at all.
If i was doing some major filling like a mk4 golf bumper recess i would buy the proper welder,just for quickness really.Theser are about £90 on ebay.
But if your doing anything like what i have then you will get on just fine with that gun.
Just remember to clean your tip every now and again and if your doing hours at a time,swap your ends regularly as i found if they get too hot after and hour or so they are a little bit harder to use(as daft as it sounds)
But there are 2 supplied in the kit so its all good :)
Title: Re: Plastic welding advice.
Post by: shepgti on 20 March 2011, 15:45
nice one, cheers