Product Spotlight: Arjay 6011


We have spent lots of time talking about coring material. Coring is a big part of the fiberglass industry and an essential component in boat making. However, not all coring comes in sheets. One of our many really interesting products is a putty by Arjay products called 6011 Ceramic Putty, and this product can save a lot of work!

The Pourable Ceramic Transom putty is sold in 5-gallon pails and is meant to be a liquid coring material that dries extremely hard and rigid; perfect for transoms or stringers in a boat. Why is that exciting you may wonder? Simple; if you are repairing a soft transom, which is when the wood gets wet and needs replacing; instead of completely replacing the transom, you can simply dig out the wood and pour this product in. Once the gap is filled, and the putty is cured, you are done! Often times, the transom is harder and stiffer than ever before!

So, let’s talk specifics. The exotherm on this putty is relatively low, which means that you can catalyze the entire pail and pour the full five gallons without worrying about combustion. Arjay recommends you catalyze at 1%, so an 8oz bottle of MEK-P Catalyst should do it. Gel time is about 18-20 minutes, so you have some working time with this product. Obviously, you can extend that time by cooling the product down ahead of time.

With large pours, Arjay recommends one single pour, so you want to get everything ready to go ahead time, so you can maximize your time. You CAN do multiple pours with this product. Ideally, you want to perform multiple pours before it cures, but even after it cures, you can add another pour, but it isn’t recommended on anything structural because it does create a bit of a seam.

One important bit of information I learned first hand is not to spill it. Once this stuff cures, it’s extremely hard. It’s a tough grind to get off a surface, so make sure you clean it before it cures.

We even have a Handy-Dandy estimator for how many pails you need. Download it HERE: Arjay6011Calculator

Tech-Tip: Coring Material

Coring Material is a very important step in your fiberglass project. Coring is what takes a sheet of fiberglass and turns it into a solid panel, for decks, boats, and so much more. Coring material can give the sheet flexibility, rigidity or even insulation (which is important when making a cooler). We carry several different kinds that offer pros and cons. It’s important to find the material that works best for you.

Honeycomb –


  • PVC honeycomb with a fiber covering.
  • Very flexible and light-weight.
  • Does not rot and has great bonding properties.
  • 5lb density sheet

Diab –


  • Offers several densities (3, 4 and 5lb denisty) for different jobs.
  • Much more rigid than plain polyurethane foam
  • Tan color (used to be multi-colored).

Polyurethane foam –

Polyurethane foam

  • Great in-expensive coring
  • Light-weight
  • Does soak up resin and has a good bond.
  • Does compress if you aren’t using the proper density.
  • Greatest R-Value (insulation) of any of our options.
  • Sold in 2lb and offered in 4lb density

Kay-Cel –


  • 25lb density sheet with 18 oz Woven Roving in the middle
  • The most dense, heavy material we have
  • Perfect for transoms or pieces with a heavy load

Balsa-Core –


  • Seal-coated wood to reduce resin consumption, keeping the weight down and increasing the bond.
  • Very lightweight, and inexpensive solution.
  • Does eventually rot without proper sealing.
  • Very good compression tolerance