I did what I could to prevent my spars coming out warped, but still wound up with 3 out of the 6 taking some kind of curve. The worst are the main yard and main mast. I worry less about the yard; it is the easiest to remake if I decide I can’t live with it. The main mast originally had a very slight curve which I chose to orient with the concave side facing aft. At some point after the second coat of epoxy it developed a curve which, if left unchanged, will have a concavity to starboard as well. It is quite noticeable when sighting down the length or laying on a flat surface but I’m not sure it can be readily seen otherwise. I won’t know for sure until it is standing in the boat. I know wood is never perfect, so If it looks ok I’ll be happy.
The materials were stored indoors in an air conditioned room flat on a laminate floor for the latter part of summer and into the fall. After assembling in the fall, the spars moved from my office/den to the workshop for shaping. My workshop is indoors as well, but it is cooler than the rest of the house, and probably more humid. I epoxied them as soon as I could but it took several days. The warping appeared almost immediately after epoxy and has remained unchanged since then.
I’m getting ready to finally finish this boat now that I have time again and we’re emerging from the deep-freeze 
I can’t think of much you can do once they have epoxy on them. What wood are they made of?
Maybe move them outside a while and see if they un-warp?
Steam bending or just heat bending comes to mind. Clamp it to the right shape (plus allowing for spring back). However: softwoods don’t bend well this way, it would soften up the epoxy, and if the bend is over a long length it will be difficult to set up.
if the spars are usable, I think I’d just use them. You may enjoy the sailing so much you forget about it, or it will gnaw at you every time you look at the mast. If it’s the latter, then keep sailing and resolve to make new spars. If you make new spars, a common trick is to cut your material in half lengthwise and flip one piece end for end and over so that any bending stresses counteract each other. On my Passagemaker I sorted through the box store hem-fir 2x8s and found one where I could cut two pieces and avoid the flaws and large knots. The bigger boards are ‘usually’ better. Did the double flip and epoxied them together.
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I’ve consulted with AI on how to potentially reverse the bow (heat and steam both came up. Steam would require removing the epoxy first). I’m not sure I will attempt a reversal since the spars seem to have stabilized as is. I could make things worse, or they could return to their preferred state anyway.
@Steve_Sawtelle I think I agree. Hopefully the effects are minimal and I can remake the spars while the current set are in use. I won’t delay sailing the boat if I don’t have to. In the conversations I’ve had with AI, the robots feel that the lug rig can accommodate the amount of curve I am looking at with no ill effects. So it will be down to aesthetics as to whether or not I can live with it.
I’ve always wanted to learn more about spar making anyway 
The fore/aft bend can be compensated for, up to a point by moving the boom fore and aft and by adjusting the rigging of the yard parrel.
The starboard bend can also be compensated for, again up to a point, by wedging the mast to port and adjusting the downhaul tension.
In general, your primary goal should be a good sail shape. Once you’ve got that, try it on the water to see if there’s any adverse helm. Only of there is do you need to worry about re-positioning the mast. Remember, half the time a balanced lug is fouled against the mast and that seems to make no difference at all. Unless your mast is badly curved you shouldn’t see any difference at all, unless you’re a cutthroat racer.
Laszlo
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