Spray Rack News


April 29th, 2018

Effective immediately, our main phone number is changing to 952-471-2623. Orders will be taken between 9:30 and 2:30, Monday through Friday.

RM Group to present at RCI Convention

March 11th, 2016

Todd Mikkelson, inventor of the Rain Maker spray rack and owner of the RM Group, will be presenting “ASTM in the Real World” at this week’s RCI Convention and Trade Show in Orlando, FL. The convention is being held at Rosen Shingle Creek Resort March 10th – 15th and Todd will do two presentations the morning of Monday, March 14th. If you’re attending the convention, come by and say hello!

NEW — ASTM C1715 Masonry Device

February 19th, 2016

Our new ASTM C1715 Masonry Wall Drainage System Performance Device can be used alone or connected in line with more than one. It’s ready to go right out of its padded carrying pouch. Sets up in seconds. Comes with six hoses.

Price:  $780.00
includes ground shipping in the continental U.S.

Rain Maker Horizontal for Roof and Surface Testing

February 19th, 2015

For testing horizontal surfaces. Add to your current Rain Maker spray rack, get a full Rain Maker with added horizontal feature, or get the Rain Maker Horizontal on its own.

Click here for pricing and details

Rain Wand Boom extension arm

April 11th, 2014

The Rain Wand Boom extension arm extends up to 6 feet. Attach the Rain Wand AAMA 501.2 device to this telescoping extension arm and test high surfaces, while staying out of the spray yourself!

PRICE: $235.00
(does NOT include Rain Wand)

Spray Bar Stabilizer Clips

February 21st, 2014


Add these to the Rain Maker spray rack to help stabilize the extended spray bars in commercial applications where the bars cannot be reached to adjust if needed. Choose set of four, six, eighteen, or any amount.

4 – $125.00
for a regular Rain Maker

6 – $175.00
for a Rain Maker with Horizontal Extension Kit

18- $450.00
for a Rain Maker with Horizontal and Vertical Extension Kits

Booster Water Pump

December 4th, 2013


Introducing our NEW booster water pump — our choice for boosting water flow on the job site. This multistage, 660 GPH, 1/2 HP booster pump will boost PSI up to 110, allowing you to achieve the necessary pressure when using additional spray bars with the Rain Maker spray rack.

We converted and pre-assembled all electric power and hose fittings so you can hook up regular garden hoses with quick-coupling ease.  Very durable.

PRICE: $595.00



Testing in high places

November 26th, 2012
Recently, the Rain Maker spray rack and the Wind Maker PLUS test kit were used to test new windows being installed in the Minnesota State Capitol building.

Check out how our products can help YOU
Visit our newly-designed web site:  www.sprayrack.com


Differences between ASTM E331 & ASTM E1105

April 20th, 2012

“I have read both ASTM E 331 and ASTM E 1105 and can’t find any difference between the two test methods. It stands to reason that there is a difference, otherwise why two test methods? Can you please explain the difference between them?”

There are fundamental differences that are revealed in the titles of each standard.
These are identified with italics below:

ASTM E 331 — Standard Test Method for Water Penetration of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static Air Pressure Difference

ASTM E 1105 — Standard Test Method for Field Determination of Water Penetration of Installed Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform or Cyclic Static Air Pressure Difference

Other differences:

  • The E 331 describes the test specimen being affixed to the air chamber
  • The E 1105 describes the air chamber being affixed to the test specimen

Hence the 1105 adding the specification of Installed test specimens, and specimens in the field. Included diagrams show these differences. In short, the 1105 is easier to comply with in the field.

It is difficult to find these and other differences without actually placing the two standards next each other, page by page. There is another very similar test method, ASTM E 547, which only allows for the cyclic air pressure procedure. It is also interesting to note that there are two AAMA standards that refer to these ASTM standards for most of their procedures and are performed in nearly identical fashion.