1970 Flatback 222 - Barn find Revival

[Ulysses485]

Rickk, I actually started off with chopped strand matt to fill the 20'' transom void and then another full layer of 3/4oz matt over the whole transom before I started laying the rest. The 3610 is a 0/90 25'' roll that is indeed heavy stuff but I have gotten use to using it and wetting it out properly. Takes a lot of time, finesse, and A LOT of resin. Nearly the entire inside bottom of my 240cc got a layer of it so I have had my fair share of fight with it. The 2408 is basically the same as 1708 but a little heavier and I used a 12.5'' roll. I have to taper the edges of the few lap sections and I may or may not add another layer or two of 1708 for good measure. I have a 60” 240lb roll of 1708 that I plan to use for decks. I would have never bought such a large roll if I knew what I know now. Managing shorter /lighter rolls for me is much more doable.

I may just add biaxial glass to both sides of the 1.5'' coosa on a table but I haven't decided yet. I was over exhausted when I was done with this at 2am that evening and couldn't go further but still ended up with 1/4”. I’m considering using a vinyl-ester based core bond in pails so I can also use it for coring the hullsides.

Question: how many gallons of resin or bonding agent do people typically use the bed in the core? I was thinking a gallon would be plenty but guess I should do some sf calculations.

[Duffy1470]

I will also be interested in gallons / Sq ft for core. Ulysses, I didn't realize you were in the middle of a build. Don't know how I missed that.  Looks awesome.

[Ulysses485]

I think I figured it out based on flooring material spread through a trowel. I have a bunch builds going on. The links are all in my signature below.

[Ulysses485]

Looks like a 1/4'' x 1/4'' trowel will spread a gallon over 32SF so using the 1/4'' x 3/16'' trowel that I have, a 1/2 gallon of "peanut butter" should suffice to bed the coosa. Probably get 4 quarts ready to be on the safe side. I'm thinking of laying up 2 layers of 1708 on coosa (both sides) a few days prior. A layer or two of matt on the exterior skin to go wet on wet with the 1/4'' layer of "peanut butter" troweled on the Coosa. Id much rather overbuild than under build.

[Ulysses485]

Got the transoms skinned with 2 layers of 1708 on the inside where the the core will meet the outer skin. Trimmed and ready for Arjay 4001 Corebond. Note: These are two (2) 1.5'' transoms for two (2) different builds. See signature for other rebuilds

[Duffy1470]

Super cool. Used the chart you posted last night. That is by far the best thing I have gotten off the internet. Thank you again.

[Ulysses485]

  I’m glad it helps. Not sure why I didn’t think to post it sooner in my threads. I don’t think it’s a “manufacturer secret” but I’ll give the credit where credit is due and that is Mirage Manufacturing in Gainesville, Fl. I bought most of my materials from them since 2019. Only recently have I started using a more local supplier because I changed jobs and their pricing is also more competitive. The first thing I do before layups and catalyze my resin is reference this chart.

[Ulysses485]

Did a quick test fit for my DIY 2x4 clamps. Should do the trick!


Decided to put a tape line on the inside where the core bond will eventually ooze out. I marked just outside the coosa when it was set in place with magic marker. This should help me from having too much cleanup after I create a radius to the inside corners. Once I get the radius completed I can pull the tape for no cleanup...at least that's the plan. We will see how it goes.

[RickK]

Nice clean work Ulysses   

[Ulysses485]

Transom core was set in early December. Solid as a rock. I thickened some resin with cabosil and some cut up matt. The coosa (which has two layers added of 1708) was prepped with a grinder and then a layer of Core Bond Arjar 4001 was used to set the core.

Need to grab a couple more pails of resin to get the inside layers done so i can start the hullside coring. The hull side will get cored with 1/4'' Divinycell (scrimmed and scored) .....I don't think the 3/8'' that I also have will fit (will be used for my 240). I plan to use the original liner that will get an added layer of 1708 on it. I think there is enough of an existing gap between the hull and liner but we will see when things start coming together. 

[Ulysses485]

The outside stringers are now re-filled with foam. Once the transom inside liner is done, I can tie the stringers to the transom, and cap the outside stringers with a layer of glass. They will get capped on the hull side up about 4-6'' and in between the next stringer with 1708 tape. Once they are capped, the hull sides will get cored with the 1/4'' divinycell and capped with at least one layer of 1708 before the inside liner goes back.

[Duffy1470]

More progress! Double excellent.

[Duffy1470]

Any updates? Certainly not racing you, but definitely motivating to see progress on your build. Been using the chart. What a great asset you bestowed upon us all. I can't believe the product doesn't come with one.

Anyways, hope all is good and give us a Pic or two.

[Ulysses485]

Any updates? Certainly not racing you, but definitely motivating to see progress on your build. Been using the chart. What a great asset you bestowed upon us all. I can't believe the product doesn't come with one. Anyways, hope all is good and give us a Pic or two.

Unfortunately, I ran out of resin back in January and haven't had a chance to run out to Daytona to pick more up. They only had one pail when I went out there last which I was not expecting. I am hoping to be able to get a bunch of grinding done over the long weekend so I can get ready to core the hull sides of this one. Thanks for the motivation!

[Ulysses485]

Got some motivation/time over the long weekend with some well needed cooler weather (its February, what happened to winter?!! LOL) and figured I would take advantage of it!! Got the cap lifted with the carport frame and got the gelcoat up front knocked off and all the hullsides hit with 40 grit. I will be coring the hullsides with 1/4'' or 3/8'' scrimmed and scored divinycell and capped with a layer of 1708. Before that I plan to layup a 12'' tape of 2408 on the outside stringers to cap them off and stiffen up the hull and outside stringer form. All the stringers are going to get at least a layer of 1708. They didn't build the flatback stringers with anything else but chop strand matt so it needs it on rebuilds.