3M Ribbon Butyl Tape: what size is best?

[Topcat]

Getting ready to install front windshield.

What diameter Ribbon butyl tape is the best/right thickness to use?

3/8" or 1/4"?

[67vertman]

Mike, I used 3/8 on mine and still needed to add some extra in a few areas. 

two tips, first leave the cover paper in place and test fit the windshield to see if you need to add some extra thickness in any areas.  second, test fit you trim molding to make sure it works as well. 

It also held to have a friend or two handy to put the windshield in, or those siction cups to hold the windshield.

[Topcat]

Mike, I used 3/8 on mine and still needed to add some extra in a few areas. 

two tips, first leave the cover paper in place and test fit the windshield to see if you need to add some extra thickness in any areas.  second, test fit you trim molding to make sure it works as well. 

It also held to have a friend or two handy to put the windshield in, or those siction cups to hold the windshield.

I picked up 15 feet of the 1/4".

will that be enough?

[johns cuda shop]

I believe it has to do with the thickness of the windshield .A original glass like a AMD is thicker than the type you would get from your local glass supplier. Wasn't the factory bytle tape 5/16 ?  I thinking a 1/4 might be too small. I would like to know myself. I'm sure someone will chime in.

[Kapteenikosmos]

I also used 3/8 which was mostly fine. I had to add some extra into couple of corners though. 1/4" would have been way too small in my case but I have a local repro glass and never compared the thickness of it to the original.

[acudadude]

Just started my windshield removal and read some old posts here ; most were using 5/16'' 3m ribbon if you used the thicker 3/8'' they said your trim moulding would not fit. I did use 5/16'' on my old 70 cuda for the back window ....you my want to reck the 1/4'' just my 2 cents.

[anlauto]

3/8 is what you want.

[mopar jack]

I went with the 3/8 for my AMD front window. Figured it would allow for a little settling over time when it sits in the sun. The trim is just a tad high in a couple of spots but nobody  seems to notice. I don't like the new stuff that the glass repair shops use. That stuff sets to hard and our cars flex more than new ones so I worried that the window might crack. Have a friend with a challenger let a glass shop install his with the new stuff and they got some on the interior trim (A pillar covers) and can't remove them.

[acudadude]

Mike what size did you use on your install please let us know thanks.

[Topcat]

Now I find a version that is flat log style.

Is this a preferred design or the round?
Perhaps it doesn't matter?

http://www.ebay.com/itm/171224097333?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2648#ht_460wt_900

[72cudamaan]

    Inquiring minds want to know. 

[Topcat]

I believe it has to do with the thickness of the windshield .A original glass like a AMD is thicker than the type you would get from your local glass supplier. Wasn't the factory bytle tape 5/16 ?  I thinking a 1/4 might be too small. I would like to know myself. I'm sure someone will chime in.

AMD glass requires the smaller butyl rope. You're correct that AMD glass is thicker than OEM and needs to be taken into account for that.

Put on the 3/8" on and the glass sat too high.
We had to pull it off, clean the mess and put the smaller 1/4" on.

Trim sat right. Lucky I bought both sizes just in case.

[Skunkworks Challenger]

I have AMD glass and the 3/8 rope (round) style worked perfectly.  I mocked up using smaller sizes but went with the 3/8.

[jimynick]

Mike, 3/8's was what we used back in the day and you want the fresh stuff as it'll flatten as you install it and the old stuff was too hard to do so properly. There was also a butyl primer you used, as well. It came in a can with an applicator brush and was black. Having said that, you can get different modulus rated urethane which has different settling characteristics/heights. They cut this stuff out everyday on all makes of cars so don't be afraid of it. Good luck. Ian

[ToxicWolf]

I have the front and rear out at the moment on my 70 Challenger.  I was going to look for some 3\8 square since my glass is original.  Should I use round instead?