Recurve Build Log

[Pago]

I didn't take pics of the riser glue up but it's not very elaborate.  Ash with a purple heart accent, the only reason for the accent was to achieve the height I needed.  I built a little hot box and modified a space heater. With my digital control it worked great.  I still need to build the large hot box and will post some pics then.

This ash is super hard nothing likes to cut it.  For those limping by with a 10" craftsman bandsaw like me, don't give up.  I bought aftermarket bearings and followed this setup tutorial.    Band Saw Clinic

Works good and cuts square for the first time.

I cut the riser out today and with a little work go it ready for glue up.  I cut just outside the lines and used the rigid sander the rest of the way.

Test fit to form. I worked it until there was no light showing through between the form and riser.
     

Finished riser.
     
 

The ends of the riser came out great.  This picture doesn't do it justice I'm not steady enough to get the shot. They are super thin.
     

Comments and suggestions welcome.

[bigbob2]

Looking nice, can see how thin those fades are.Keen to see more .  

[Pago]

Time for another update on this saga.  Mostly finished my hot box this weekend.  It was a cool 97 degrees this weekend so I jumped on it. Shop time is hard to come by in the summer here with triple digit temps.  I need an air conditioned shop some day.

 
Outer dimensions are 84'x12'x32"

 
I'm planning to use my hacked space heater with a digital control it has worked well in testing so far. Handles, lachtes and wheels yet to put on.

[Pago]

I'm one happy guy. Set up the oven today, it holds temperature nicely. Setting it up with the space heater was an interesting process it's all about airflow. There has to be enough ventilation so that there is no or very little back pressure on the space heater. I ended up with 28 3/8" holes on each end. This ends up at about 74% of the diameter of the fan opening on the space heater. Good even heat distribution throughout the oven. It reaches temperature in under 4 min.

 

 

[bigbob2]

That is one nice hotbox! I wouldn't want to post a shot of mine!Temp is regulated by 'cracking' the lid as needed.

[mikkekeswick]

That's coming along nicely.

[Pago]

I probably went overboard with the hot box but the hope was to make it once and as user friendly as possible.  With the testing I went through is was apparent that there is a huge temperature difference from the top to the bottom in a box with no air movement be it using light bulbs or otherwise.  With a set point of 170 F I am running 167 F average across the whole area. Now back to mocking up a dry run and hopefully gluing up my first bow soon.

Thanks for the kind words.

PS infrared thermometers are useless for measuring air temp and on foil insulation, you probably all knew this but dummy me just figured it out.

[Pago]

The hot box build was loosely based on this one by bjansen. Its a great build along.  bjansen hot box build

If useful below is a link to download the sketchup file created for my build.

 Sketchup oven plan

[Pago]

Well I don't know where to start maybe I shouldn't have at all.  I hit it at 0630 this morn with a lot to do. I spliced the lams and did a dry run cut all lams to size. This is when things went to pot. The riser that I had fiercely guarded fell off the form when the wind blew into the shop,broke off both ends. I almost burned the whole lot. I started this bow in January. I couldn't bare the thought of building another riser. I cut the riser down from 20 to 18 inches and re-tapered. Added some tip wedges hoping to regain some stability.  It's 106f in the shop by now. I think the heat got to me, I was on mission it was going in the hot box today or never.  Seemed like things were getting better, set up to glue and had a plan.  I had all but the last two lams on and the smooth-on kicked off, boogers everywhere.  Scrambled to scrap them off and mix more epoxy.  Finally got it wrapped and in the hot box at 1830. Out of breath, heat exhausted, heart pounding. As I set it up in the hot box I think I saw that the riser had slid, I didn't ivestigate, couldn't bare to.  It's probably junk, I'm sick. I'll post a post mortem after I check it out tomorrow.  Most of y'all make it look easy, it ain't or I'm just dumb as a post can't decide right now. Hope y'all have better luck.

[bigbob2]

only difference is we haven't posted all our stuff ups Pago! I have absolutely no doubt we all have similar stories if we dared to tell.i wrestled one of my earlier longbows about on the form until it ended up with glue starvation need the top of the fade ramps.And that's only one example!I hope it works for you and can relate to nerves waiting on outcome of hotbox. I think every time a bow goes in mine I still worry about the outcome.

[Pago]

Thanks Bob, now I can't believe I posted that. I did get a touch of heat exhaustion. I was not myself when I wrote that guess I needed to vent. I peeked at the glue-up this morning and riser did move which also created a gap I doubt it will be shootable. If only I could TBT.

Things learned:

In Arizona don't mix up more than 4oz of smooth-on at one time.

In the summer here glue ups need to happen early-early in the A.M.

Always put the riser back on the bench.

When you apply the second round of rubber bands double check the riser even if you know the epoxy is already kicking off.

Better yet, use a firehose, I may use the glued up mess to make a template for a top to the form.

[Mad Max]

I have never broke the fades off the riser
       :rolleyes:      

[bigbob2]

and your nose id getting longer by the second!        Pago have you thought of drilling a hole under center line of riser form and just using a zip tie to really hold that sucker in place . I do and it wrks well.

[Mad Max]

I use a 1/8" wood dowel, close to the edge of the riser where it will be filed off to pin the lams to the riser/ form

[mwosborn]

I am betting you get a bow out of it by the time your done.  The first is normally not the best bow you will ever make - there is most definitely a learning curve.  It does get easier.  I am working on my 5th fiberglass bow now - the glue up go smoother after you have done a couple - however, it seems like there is always something that comes up!  Those that are way up on that learning curve sure make it look easy!

[Pago]

The pictures tell the story.

 

 

 

 

 

 

 

 

[Pago]

Tip wedge

 
Other tip wedge

 

 

 

[Pago]

I'm wondering if I could split the back lams away from the riser.  Does anyone think it will be possible to cut a section out of the center of the lams on the riser and glue them back down? I could cover the split with an overlay?

I hate to bin it the glue lines look pretty good to me everywhere else. Input appreciated.

[inksoup]

if limbs glues are fine, you can drop some epoxy on those holes and C-clamp it. you may save the bow.

[Pago]

I don't know where this is going at this point may not be anywhere good.  The misadventure continues....

I was able to do what I wanted and split the back layers away from the riser and cut them horizontally. This will allow me to do some sanding behind the glass and smooth things out.  I'm going to thin some smooth on and inject it in a few places, then glue everything back down and cover the split with a fiberglass overlay.

One limb is two inches longer than the other, there was some of this in the design but it is exacerbated by the movement of the riser. I'm still working out this problem, initially my plan is to put the longer limb on top and see where I end up.