The Glazing Putty Test

By Scott Sidler May 29, 2017

glazing putty testFrom time to time I like to do product testing here on the blog because it helps me find the best products out there and share them with you. You can check out my most popular test to date the Wood Filler Test (Year 1 and Year 2) for some useful testing. Today I thought it was about time I did some head to head testing on glazing putties.

In my shop we glaze about 600 LF of putty every week so making sure we are using the best putty that is not only easy to use but performs better than the other products on the market is of vital importance. I’ve written about Which Glazing Putty is Right For You previously, but have never done head to head testing of multiple products. Plus I’ve included some additional putties that I don’t have experience with but are readily available so I’ll be learning right along side you.

For this test I have glazed a 3-lite sash with the various putties and left the sash in my shop for approximately 4 weeks before taking it outside and leaving it exposed to the elements unpainted. Here’s what I’ll be looking for in the testing and will rank them on a scale of 1-10 (1 being the worst and 10 being the best)

  1. Easy of Application
  2. Clean Up
  3. Appearance
  4. Cure Time
  5. Mildew Resistance
  6. Long-Term Performance

Below are the products that will be a part of my glazing putty test. I also snuck in my own glazing putty recipe to see how it performs with the rest. Soon we may have some of our own glazing putty available for you readers too! Test points 5 and 6 won’t be evaluated this year but in the upcoming years we’ll be able to see how the putties perform on these items.

Crawford’s Painter’s Putty

crawfords glazing puttyThis a new putty to me that I have seen on the shelves at paint stores but never tried until now. This is a linseed and calcium carbonate putty with titanium added. It’s a natural product with no harsh chemicals and very similar to the traditional putties of the old days.

The putty comes in a sealed metal can and has a layer of water on top that needs to be poured off and blotted dry with a rag before digging out some putty. The water keeps the oxygen off the putty and prevents it from developing a skin on top which saves you from loosing a layer of cured putty which is nice.

Right out of the can the putty was simple to work in my hands and tools pretty nicely. I didn’t have any problems with the putty sticking or clumping and it was easy to work with my glazing knife. It is oil-based so clean up really consists wiping it off your hands with a rag and then washing a couple times with soap and water, but in the end it does come off.

As far as the cure time, I was impressed that after only about 1 week the putty had developed a good enough skin that it was ready for paint.

  1. Easy of Application – 8
  2. Clean Up – 6
  3. Appearance – 8
  4. Cure Time – 9

DAP “33”

dap 33This is an old standard for a lot of window glazing. I’m not a big fan of it from past experience, but I decided to give it another try for this test since it had been a few years since I last used it. In my opinion the greatest strength of DAP 33 is that it is available at almost every hardware and paint store in the country.

The putty was very thick and oily and difficult to work with a putty knife compared to the other putties I tested, but I was still able to get a smooth putty line. The clean up is much like the other oil-based putties requiring wiping off then washing thoroughly. It took just about 16 days before the putty had a sufficient skin enough for painting which is on the long side for glazing putties.

One small benefit of DAP is its white color. Since a vast majority of the sashes I paint are white it is much easier to ensure good coverage of the paint on the putty rather than with the natural tinted putties.

  1. Easy of Application – 4
  2. Clean Up – 6
  3. Appearance – 8
  4. Cure Time – 5

Sherwin Williams “66” Glazing Compound

66 glazing compoundI’ve seen this putty on the shelf at my local Sherwin Williams store and have wondered how it performed so I forked over a few bucks and brought a quart back to the shop for testing. The putty is white in appearance just like DAP 33 and when I dug it out of the container I found it to be a sticky, gooey mess to work with. It stuck to everything including my gloves so much so that I had to take them off and use my bare hands.

The stickiness of the putty made it feel more like a paste than a knife grade putty. The stickiness did make it easy to adhere to the glazing rabbet but other than that I did not enjoy working with this putty one bit. Trying to tool a smooth finish was not an easy task and I’m a pretty darn good glazier.

Cure time was about 13 days before it was ready for painting. Even if this putty performs amazingly I would not recommend it because it was such a pain to work with.

  1. Easy of Application – 1
  2. Clean Up – 3
  3. Appearance – 6
  4. Cure Time – 6

Sarco MultiGlaze

multiglazeAt the time of this writing this is the putty I use everyday in our shop. I included it in this testing even though I am immensely familiar with MultiGlaze because I wanted to have a baseline by which to judge the other putties with. MultiGlaze is a linseed oil putty and has a beige/grey appearance. It is extremely easy to work with and has just the right consistency to stick to the sash and not stick to your hands and tools.

It tools easily and leaves a super smooth bed of putty. Not only that but it cures in about 3-4 days and is ready for paint at that point. The only down side to it is that it is not meant for on-site application. Sarco recommends that it be glazed in the shop and then painted before it is placed into service.

  1. Easy of Application – 9
  2. Clean Up – 6
  3. Appearance – 9
  4. Cure Time – 10

Scott’s Putty

For this test I decided to add my own mixture of putty into the testing. I used a traditional glazing putty recipe of raw linseed oil and whiting. It was a little difficult to find a good mixture because when I made it thick enough that it wouldn’t sag it was then very hard to work with my glazing knife. When it was thin enough to glaze easily it was too thin and would sag.

Clean up was much the same as the other putties which wasn’t surprising. I knew that by using raw linseed oil instead of boiled linseed oil the drying time would be extended but I was surprised by how much slower the skinning over time would be. It took about 26 days before the putty was ready for painting which is crazy long!

While it was helpful to see how a traditional linseed oil putty performed compared to modern glazing compounds it was particularly helpful for my testing while I try to develop my own putty. Right now I would consider this putty a fail, but testing and learning is never a failure in the end.

  1. Easy of Application – 3
  2. Clean Up – 6
  3. Appearance – 5
  4. Cure Time – 1

This is only the first year of my glazing putty test so be watching for future posts to show how these putties perform out in the elements.

2 thoughts on “The Glazing Putty Test”

  1. Nice to see this head to head. We used SW 66 on the advice of a man who does colored glass restoration since he learned it decades ago as a teen from the originator of the shop he now runs. he said it was much better than DAP, but maybe he had never used sarco.
    My daughter did a fine job in spite of using SW. We’ll have to get the sarco.

    I am assuming that one can use sarco in place, not in the shop, if one protects from rain before it is painted, or am I missing something??

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