New on here with problem # 1

[simk]

Hi everybody 🤗

Lurkin' around here on the quit for a few years already and was always impressed and interested in the wealth of laminating knowledge. Thanx everybody for sharing!

I myself make wooden bows. Selfbows, backed bows and multilams.
I recently got a batch of tropical wood and ran into issiues. Some of the wood seems so oily that my thickness-sander and beltsander both refuse their work. instead of dust it produces kinda oily abrasive immediately clogging the pores of my sanding paper and burning the wood...

I'm using 80grit paper. Would it help buying 40 or 60 grit?

Is it maybe due to the poor quality of my sandingpaper?

Other ideas to tackle this?

Thank you very much!

Best Greetings, Simon

[Roy from Pa]

Welcome Simon

I would try 40 grit.

Nice bows.

[simk]

Thank you very much Roy 

My follow-up Q now was..: Does a 40grit sanded surface visually affect my gluelines, make them look less precise?

Cheers

[Roy from Pa]

Are you referring to the surfaces being glued together, then no.

After I get my lams to where I want, I run a toothing plane down them to increase my gluing surface before glue up.

And final sanding after bow is all tillered will take out any small irregularities.

[mmattockx]

Thank you very much Roy 

My follow-up Q now was..: Does a 40grit sanded surface visually affect my gluelines, make them look less precise?

Cheers

Welcome Simon, good to see you over here. 40 grit will not make the glue lines any visually different than 80 grit.


Mark

[simk]

Thanks again Roy 🤜🤛
That is more than answering my question.
I sometimes slightly toothed some glued up handles and remarked the toothed grooves on the finished product...but of course its located different and probably less visible from the sides...
I used a metal saw to tooth the lams but its a lot of extra work which I nowadys just skip. Do you have a pic of your toothing plane or a link to a pic of such device - sorry....the newbie just wants to know evetything 😅 found

Hello Mark, that's another good news, thank you 
Cheers

[Jeff tech]

80 grit is too smooth. 40 will be just fine. JF

[mmattockx]

80 grit is too smooth.

Not according to Smooth On, they recommend doing surface prep with 120 grit.


Mark

[Jeff tech]

120 grit yeah right, I wouldn't no way

[kennym]

Most bowyers I've talked to like at least 50 grit, some down to 36. I use 50 on lams I grind.

Overlays where you feather them in may show a smoother transition with finer grit, but they aren't holding the limb together.

[Roy from Pa]

I use 60 grit on my edge sander and I still get a rather smooth finish, which I don't really want for glue up. After the lams are close I run them through the drum sander with 60 grit paper. That's why I use a toothing before glue up. But I make all wood bows.

[mmattockx]

120 grit yeah right, I wouldn't no way

That's fine, but I'm just pointing out that the manufacturer of the epoxy most of us use recommends prepping with 120 grit. If they don't know their product, who does?


Mark

[simk]

Nice to meet more all wood laminators 👍 I ordered some 60grit too now because 40 was nor available in my dimensions (or google did just not found).
I think Roy might makes what works and feels best for him Mark 🤗 everyone in this mystic art has their own recipes to a certain degree, so do I sometimes...

[mmattockx]

everyone in this mystic art has their own recipes to a certain degree, so do I sometimes...

I agree and I don't use 120 grit, either. But it is always good to know what the manufacturer recommends as a starting point.


Mark

[Roy from Pa]

Who the heck has time to read the instructions on a can?

 

[Jeff tech]

Manufactures and real life are two different things. I will go finer on overlays because I don't want that feathered look when it gets thin, on the mating fine edges. 40 grit gives great adhesion between laminations and it does not show up under clear glass.... I've built a few, no failures.JF

[Jeff tech]

I use smooth on epoxy. JF

[Kirkll]

  I've been using 36 grit and 40 grit on my lams for 15 years and never had an issue.... But keep something in mind.... With all epoxy, they typically don't recommend high pressure lamination. So gluing two smooth pieces together using 120 grit will be stronger with less clamp pressure. Same thing with glueing other smooth surfaces.

I've done limb lay ups with an air hose system at 25# pressure that came out fine.

You will get a lot of debate on toothing, vs smoother surface lay ups from different people with different applications. but bowyers using air hose forms and 50-60# of pressure use 36-40 grit toothing with  EA-40 with excellent results.

One other thing that hasn't been mentioned here is the importance of cleaning your sand paper often with oily woods. and go easy on how much you sand in one pass. if you are running a drum sander, run your boards in different locations on your feed belt, and clean the paper with one of these often.

https://www.amazon.com/POWERTEC-71002-P2-Abrasive-Cleaning-Sanding/dp/B099WMPH2W/ref=asc_df_B099WMPH2W?tag=bingshoppinga-20&linkCode=df0&hvadid=80470626682203&hvnetw=o&hvqmt=e&hvbmt=be&hvdev=c&hvlocint=&hvlocphy=&hvtargid=pla-4584070155902425&psc=1

 Kirk

[simk]

thank you Kirk - that is some real solid advice!
Interesting to hear that the Pro's mostly use low to very low grit. I've usually only sanded to 100grit in the past, using all types of glue (fishglue, different epoxy's, pva) and everything held up. Only issues I had 2 or 3 times were starved glue joints when using epoxy. In my imagination low grit or even the use of a toothing plane could minimize the risk of starving gluejoints because there will always remain enough space for some glue to stay in place instead of being squeezed out. would you comprehend/support this thought? It's just about better understanding what is going on in there...
cheers

[Roy from Pa]

In my imagination low grit or even the use of a toothing plane could minimize the risk of starving gluejoints because there will always remain enough space for some glue to stay in place instead of being squeezed out. would you comprehend/support this thought? It's just about better understanding what is going on in there...
cheers


Yes that is true.