Question for Blade-Builders

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Alright - I've finally acquired all of the supplies to make a few blades and have another couple questions for those of you who have built blades before:

1. All of my veneers came full length (over 3 meters), and are just shy of being wide enough for two blades (i.e., 295mm wide, while my blades template is 150mm wide) - what is the best way to minimize waste and maximize my veneer? Is it acceptable for the medial plies to not be a single sheet of veneer, and instead be two pieces butted up next to one-another? Would it be easier to make two blades per 295mm by 295mm square if I flip the orientation of the blades around so the handle of one is next to the blade-face portion of another?
 
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Alright - I've finally acquired all of the supplies to make a few blades and have another couple questions for those of you who have built blades before:

1. All of my veneers came full length (over 3 meters), and are just shy of being wide enough for two blades (i.e., 295mm wide, while my blades template is 150mm wide) - what is the best way to minimize waste and maximize my veneer? Is it acceptable for the medial plies to not be a single sheet of veneer, and instead be two pieces butted up next to one-another? Would it be easier to make two blades per 295mm by 295mm square if I flip the orientation of the blades around so the handle of one is next to the blade-face portion of another?

Either of those ideas will work, especially if your medial ply is at 90 degrees. Most of my 90 degree medials are in two pieces. One of Bobpuls's videos shows you how to this. It's simple, a touch of glue on the edges and then join with masking/joiners tape until cured. Don't forget to clean the excess glue up. Then remove the tape and (very) lightly sand.
You could also 'flip the orientation' too, i've done that frequently. I always try to maximise my veneers, I just don't join outer plys unless the join is low down and under the handle.
 
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Either of those ideas will work, especially if your medial ply is at 90 degrees. Most of my 90 degree medials are in two pieces. One of Bobpuls's videos shows you how to this. It's simple, a touch of glue on the edges and then join with masking/joiners tape until cured. Don't forget to clean the excess glue up. Then remove the tape and (very) lightly sand.
You could also 'flip the orientation' too, i've done that frequently. I always try to maximise my veneers, I just don't join outer plys unless the join is low down and under the handle.

Awesome - that is VERY helpful! I will keep all of that in-mind. I cut a few pieces slightly diagonally so that I can get it just a bit wider for the widest part of the blade and it's a little narrower in the portion near the handle (these are limba for the outer ply, so I want them running 180 degrees). I think that might work out okay - I just haven't glued any plies together yet since I'll be getting a vacuum bag in the mail 2 days from now. I'd rather keep things consistent in terms of the construction, as opposed to introducing extraneous variables if some of my blades are clamped while others are vacuum pressured.

First on my list will be the effectiveness and playing characteristics of g-flex vs titebond polyurethane. I think my plan is to make the first blade or two out of balsa cores, mahogany veneer, and mahogany handles (mostly because material costs are going to be about $4.50 USD to make a full mahogany blade) - I have no idea how well the router is going to cut my pattern, so I want to get good practice and minimize destroying good wood as I learn to navigate blade-building. I'll save my more expensive Limba for once I have it figured out.
 
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Awesome - that is VERY helpful! I will keep all of that in-mind. I cut a few pieces slightly diagonally so that I can get it just a bit wider for the widest part of the blade and it's a little narrower in the portion near the handle (these are limba for the outer ply, so I want them running 180 degrees). I think that might work out okay - I just haven't glued any plies together yet since I'll be getting a vacuum bag in the mail 2 days from now. I'd rather keep things consistent in terms of the construction, as opposed to introducing extraneous variables if some of my blades are clamped while others are vacuum pressured.

First on my list will be the effectiveness and playing characteristics of g-flex vs titebond polyurethane. I think my plan is to make the first blade or two out of balsa cores, mahogany veneer, and mahogany handles (mostly because material costs are going to be about $4.50 USD to make a full mahogany blade) - I have no idea how well the router is going to cut my pattern, so I want to get good practice and minimize destroying good wood as I learn to navigate blade-building. I'll save my more expensive Limba for once I have it figured out.

That seems a very wise move. Mahogany is a very underrated wood, genuine mahogany has characteristics that put it somewhere between limba and koto. You need to be careful though as there a loads of different types of mahogany and some are quite hard and heavy. Also if you are using epoxy you need to be mindful of bleed through which leaves nasty stains on your beautiful outer ply. I don't have problems with pu or hide glue, just epoxy. Sometimes it will sand out, sometimes not. To counter this I put a couple of layers of varnish on the outside of the veneer before gluing. I then sand it off after I remove from the press. What size balsa core are you using, if you have two layers of mahogany I'd suggest 5 or 6mm.
The other advantage of balsa at this stage is that you won't have to worry about weight. Even with a thick core the blade should only be 76 - 82g. When you start using cores such as ayous then the weight is more of a consideration.
 
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Alright, so I finally got a chance to build some blades.

#1: Koto-Mahogany-3/16" Balsa-Mahogany-Koto, Mahogany handle, 85 gm
#2: Koto-Koto-3/16" Balsa-Koto-Koto, Walnut Handle, 81 gm
#3: Limba-Koto-Koto-3/32" Balsa-Koto-Koto-Limba, Mahogany handle, 85 gm
#4: Limba-limba-1/8" Balsa-Limba-Limba, Walnut Handle, 73 gm

I've found a woodworking shop, and am now a member (only $50 a year!), so I can cut other core woods. I have a 7-ply blade drying right now that uses a Western Red Cedar Core, but it's looking like it's going to be around 100 gms! In the future, I'm going to try out some Port Orford Cedar (single ply and cores). Any suggestions for what I should use to seal/protect the soft balsa edge/core on these 4? I've already put on two coats of polyurethane, but that doesn't seem like enough to protect it.

Koto-Mahogany 85 gr.jpgKoto-Koto 81 gr.jpgLimba-Koto-Koto 85 gr.jpgLimba-Limba 73 gr.jpg
 
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Great work, some really nice looking blades. Consideringthey are your first blades, they are superb. Well done!
Thanks! I couldn't have done it without all of the helpful hints and tips! Any suggestions for a really durable edge protection for the soft balsa?

Yes they are really nice . Congrats and Welcome !!

Bob, your assembly videos were very helpful - especially your blade cutting video, which gave me the confidence to plunge on in with my flush trim router bit!
 
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Thanks! I couldn't have done it without all of the helpful hints and tips! Any suggestions for a really durable edge protection for the soft balsa?



Bob, your assembly videos were very helpful - especially your blade cutting video, which gave me the confidence to plunge on in with my flush trim router bit!

Try the Ross Leidy way of attaching a thin piece of veneer. In short, soak a strip of veneer, wrap it around your blade using loads of elastic bands, leave overnight. Attach with pva and loads of elastic bands and then trim and sand. It takes a bit of practice but judging by your skills you'll be fine. Contrasting colours seem to work best. I've started doing it on my blades, mainly because I like the way it looks!
 
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These blades have been amazing to play with! My current favorite is the 5-ply (koto-koto) with 3/16" balsa core. The 7-ply with 3/32" balsa core has nice control, but relatively slow speed. The 7-ply with Western Red Cedar core is incredibly fast with high throw, but it's too heavy (103g) for quick BH flicks and fatigues my wrist.

I have planed and sanded some Port Orford Cedar (POC) cores, but it looks like my limba-koto-POC-koto-limba configuration (with mahogany handles) comes out to 97g, which is still too heavy. I'm not sure how to drop some weight, as my handles are only 20g, and the PU glue isn't adding more than a few grams to the overall weight. I could make the cores thinner, but I worry that it would be too thin - the blades are right around 5.8mm right now. I cut a single ply of POC to 9mm, but it weighs 113 grams before handles...so maybe POC is just too heavy (a similar thickness of hinoki is much lighter)?

What are my options for dropping weight? Thinner cores, less glue, hollow handles or lighter handle woods? Also, what's the best way to cut the angled grip bevel?
 
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These blades have been amazing to play with! My current favorite is the 5-ply (koto-koto) with 3/16" balsa core. The 7-ply with 3/32" balsa core has nice control, but relatively slow speed. The 7-ply with Western Red Cedar core is incredibly fast with high throw, but it's too heavy (103g) for quick BH flicks and fatigues my wrist.

I have planed and sanded some Port Orford Cedar (POC) cores, but it looks like my limba-koto-POC-koto-limba configuration (with mahogany handles) comes out to 97g, which is still too heavy. I'm not sure how to drop some weight, as my handles are only 20g, and the PU glue isn't adding more than a few grams to the overall weight. I could make the cores thinner, but I worry that it would be too thin - the blades are right around 5.8mm right now. I cut a single ply of POC to 9mm, but it weighs 113 grams before handles...so maybe POC is just too heavy (a similar thickness of hinoki is much lighter)?

What are my options for dropping weight? Thinner cores, less glue, hollow handles or lighter handle woods? Also, what's the best way to cut the angled grip bevel?

Are your handles 20g each or 20g in total?
 
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Mahogany = 20g in total
Walnut = 30g in total

I aim for between 10 and 12g for each handle, which means they often need hollowing out especially if it's a heavy hardwood. Standard blades tend to be 9 or 10g, i like the balance the extra weight in the handles brings even if its is only 3 or 4g. You can sand down the blades, which can help reduce weight and speed, by 0.2mm or so. Blades often reduce in weight by as much as 3g over a period of a few weeks.
I'd also say a well balance blade at 98g feels better than an unbalanced/head head one at 92g. It's always tricky getting the weight down on 7 ply, you'll get better at predicting it over time. I would recommend weighing all your wood before you glue up. Always cut your pieces to the same size so you learn what it an acceptable weight. I can generally predict the final weight based on the weight of the uncut veneers.
 
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Thanks! What would be the consequences of dropping the overall blade thickness down to the 5.3mm range? My core (POC) is so heavy...

It could feel a bit thin and fragile, too many vibrations perhaps, however, I've never used POC so don't know! 5.3mm isn't too thin for a blade. I often make blades at 5.4mm and they feel solid. It will more than likely have good flex. Looking at the stats for POC it does look a touch heavy and hard for a core though. What about keeping it as a core but only as a 3 ply? Or perhaps use balsa as a medial ply to compensate for weight and hardness. Both of these ideas may work well but don't blame me if they don't!!!!!
 
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One thing you can do is bake the blade after the glue has set before you put handles on it. I’ve done this numerous times to take a few grams of moisture out. I bake at 185 degrees for several hours with the blade in between two heavy pieces of mdf to avoid any potential warping during the drying process. I’ve made blades in the 5.e-5.4mm thickness range and they felt fine to me. Personally I agree with Alan that Port Orford Cedar is too hard and heavy for a core wood unless it’s very thin. It is a good 70% heavier than western red cedar which is already heavy for a core wood. I think something like Engelmann spruce is about as heavy as I’d want to go for a core wood, though I know some blade builders have done some exotic things with much denser woods in very thin layers at the core. In the end it is up to your imagination to experiment with whatever seems interesting.
 
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Paulownia (KIRI) is available in the US at worldpaulownia.com,and some on Ebay.

The density of the wood I received was .27g/cm^3,which is similar to very light ayous.

Some western red cedar salmon cooking blanks I found had a density of .33.

Ayous can have quite a bit of variation in density,and I have not found a US based source in small quantities.
I used to buy .8 mm obeche veneer for roughly 1 USD per square meter around 1990 in Germany.
Small quantities of Sitka Spruce are available at Aircraft Spruce.

When glueing with epoxy you can use cabosil powder to minimize bleed thru.Basically cabosil is used as a thickening agent,
it's what makes ketchup and toothpaste stay put.
 
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One thing you can do is bake the blade after the glue has set before you put handles on it. I’ve done this numerous times to take a few grams of moisture out. I bake at 185 degrees for several hours with the blade in between two heavy pieces of mdf to avoid any potential warping during the drying process. I’ve made blades in the 5.e-5.4mm thickness range and they felt fine to me. Personally I agree with Alan that Port Orford Cedar is too hard and heavy for a core wood unless it’s very thin. It is a good 70% heavier than western red cedar which is already heavy for a core wood. I think something like Engelmann spruce is about as heavy as I’d want to go for a core wood, though I know some blade builders have done some exotic things with much denser woods in very thin layers at the core. In the end it is up to your imagination to experiment with whatever seems interesting.

Just be mindful of the glue you use. Hide and PVA won't like this but as Chris says it works well with blades with epoxy and Pu glue, I lost 7g on one blade this way. It's best to do it before you put the handles on as you risk warping otherwise.
 
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