Thinner For Dap Weldwood? All I See Is "cleanup" With Mineral Spirits.

[Tallbald]

Several on the forum mention thinning contact cement for easier spreading. It takes almost four ounces of un thinned Weldwood to double coat one of my belt blanks (once isn't enough as first does soak in) 60 inches long by 1 1/2 inch wide. Thinner consistency would be faster and I believe more economical. But I've can't find on the quart can label what to thin it with. Just "cleanup" with mineral spirits, which isn't what the glue smells like to me. Maybe it is indeed thinned with mineral spirits. Thought it couldn't hurt to ask here.

Appreciate information. Don.

[mlapaglia]

Product Description:
DAP® WELDWOOD® Contact Cement Cleaner and Thinner is a clear solvent for cleaning dried or fresh
adhesives from tools and brushes. Cleans up oil, grease spots and floor wax. Can also be used to delaminate
contact cement assemblies and other bonds.
Suggested Uses:
• Can be used as a cleaner or thinner.
• Can also be used to delaminate bonded panels.

AS A THINNER: Replace lost solvent with an equal volume of Cleaner & Thinner. Stir or mix until
evenly dispersed. Over dilution can cause loss of bond strength. Recommended only when the adhesive
has thickened beyond the point of easy application. CAUTION: Do not use to thin waterborne contact
cement.

[Tallbald]

Hmm. I don't see it next to the cement at either store I buy Weldwood at. Must have to order it site-to-store. I wish I knew what the stuff is. Thank you. Don.

[mlapaglia]

According to the MSDS its 99.9% methanol and 0.1% 2,5-dibromotoluene

You can also thin it with Xylene

FYI Xylene is nasty carp.

Suspected of damaging fertility or the unborn child

Causes damage to organs (lung) (inhalation, oral)

Causes damage to organs (nervous system) through prolonged or repeated exposure (inhalation)

May cause damage to organs (kidneys, hearing organ (loss of hearing)) through prolonged or repeated exposure

[Dwight]

Tallbald, . . .

Bubba, . . . you are doing something wrong.

No, . . . I don't know what the heck it is, . . . but I just made 4 belts the other night, . . . did not have to double coat any of them, . . . they will in all liklyhood NEVER, EVER, EVER, come apart, . . . and I maybe used 2 ounces, . . . maybe.

When you coat it, . . . use a bristle brush, . . . think metal handled acid brushes used by plumbers, . . . and just cover it, . . . believe me it does not "soak in".

It forms a grabbing surface that will grab another like surface, . . . and if you roll it with a rolling pin or press it with the palms of your hands, . . . you will rip the leather off one side or another taking it apart.

You can tell by the color, . . . if you are putting it on right. If the leather you are coating turns brown, . . . you have used WAY, WAY, too much. It'll be brown when it is wet, . . . but 20 minutes to 40 minutes later, . . . it should be very close to the natural color of the leather. That is when it is dry enough for you to put the palm of your hand on it and it not stick to you. THAT is when you stick it together.

Edited: Acetone is the product you use to thin this with. It too is nasty stuff, . . . so read the label. A very little bit is needed to thin out the bottom of the can when it gets down there. I usually thin mine just before using it, . . . and you have to stir it real good. At first it will not look like it is thinning, . . . but you keep stirring, . . . it'll be OK.

And, . . . I checked, . . . maybe 1 1/2 ounces used for a 47 inch belt, a 40 inch belt, and two 38 inch belts. Thats something under 3 square feet, . . . covered with 1 1/2 ounces of weldwood contact cement.

May God bless,

Dwight

Edited August 14, 2015 by Dwight

[Tallbald]

Dwight thanks. I took your advice last week and bought acid brushes at Harbor Freight. Gotta love the 20% off coupons with a free tape measure to boot. Yeah, my leather turns brown so it looks like I AM overdoing it. I've been palm pressing it and tomorrow plan to lathe turn a hardwood roller to ease things. I'll try using less, but I definitely don't want the edges of my straps to separate over time. I'm able to sew to within 3/16 or 1/4 of an inch while using a roller guide. Honestly I was of the belief that the contact cement would reinforce the laminates bond out past the stitches. Your experience in this matter? Don.

A comment here. I had never used contact cement before beginning leather crafting. Instructions were that "two coats may be needed on porous surfaces". I accepted that and ran with it, evidently mistakenly thinking I needed to use two. Don.

Edited August 14, 2015 by Tallbald

[Bob Blea]

Hi Tallbald,

I use Weldwood too and I may be in group that doesn't use it quite right, but I sometimes use two coats when I install pigskin liners in my notebooks. I put it on thinly (I don't thin the Weldwood at all, just thin application) and I do see my leather darken a bit at first. That quickly goes away and yes the leather can soak up the solvent. I find that occasionally I don't get a good bond in places and I need to do a second coat, but as I said I'm probably doing it wrong. And I might be putting it on too thin.

Bob

[Tallbald]

Bob I appreciate you sharing your thoughts. I'll give the one-coat a try and see how things turn out. I worry about laminate separation at an edge on a strap or belt, but know my stitching should hold things together fine. I don't see a lot of stress forming on the edges of my projects really. And for time and cost reasons I do hope a single layer of cement will suffice. Oh. Your Etsy site is beautiful and nicely done. Beautiful creations! Don.

Edited August 14, 2015 by Tallbald

[mlapaglia]

The back side of leather provides such a rough surface of the contact cement that 2 coats are not normally needed. If you glue top to top (I am not sure why you would) then you need to rough the grain up first.

As long as I get the cement out to the edge I have never had a problem with it separating at the edge.

FYI, just make sure you have a coat of cement on both sides to be glued together.

[Tallbald]

Thank you all. I do have acetone here and may give it a try experimentally. I'm a devotee of Weldwood, but I need to better learn to use it as another one of my "tools". Don