FD-Heavy Duty blades not cutting it

[shinzam]

Hi
I need some help with blades. I am cutting 2" tulip wood and a mixture of cedar, walnut, Douglas fir and mahogany strips glued together 2" thick to make sue mey inlay box. I have been using FD- Heavy duty blades but they seem to be snapping at the first tooth, after speaking with mike and doing every thing which has been suggested they are still snapping (one even broke cutting the cedar section with no pressure).
Has anyone used these blades before and had any problems with them? I have been trying every combination of speed and feed rate from dead slow to fast with no pressure at all. It has taken me 45 minuets to cut 22" of oval pattern with 3 breakages. Any suggestion on how to resolve (careful now!!!!) the breaks, should it take this long to cut. I have tried using FD-SR ~12 but with no luck, I am using a Henger with variable speed. I have spoke to Mike but he has not used these blades before.
Are there any other blades that would cut 2" wood.
Regards Graham.

[Jediscroller]

Sorry I can't help ya much Graham. I did order some of the HD blades but never got around to trying them. What problems did you have with the #12's? I cut 2" thick stuff with those or the #9 FD-SR's and never had a problem with them (this is why I never got around to trying the HD's, the 9's and 12's work so well that I never bothered).
From your description of where the blade is breaking, it sounds like too much force while feeding the wood. I do know that cutting 2" thick stock is very slow going but that's just the nature of the work.
The fact that the wood is glued up with make it somewhat tougher to cut due to the glue but it sounds like your using fairly soft woods so I don't think that would be all that big of a deal.

[KtownScroller]

Hi Graham - You are really cutting through a lot of wood all at once. Did you try a skip tooth blade? It appears that either the blades are too hard and brittle or the wood chips are not evacuating from the cut. Either way I think the blade is getting hot and snapping. Sometimes a thinner blade works better than a heavy one. You might have to feed a little slower, but it might help. Sorry I can't be of better assistance.

[tstagman]

Sorry Graham, but I have no information for you as yet. I bought some from Mike a few weeks ago but haven't had the oppportunity to use one yet.

I have some 1" seasoned oak that gives me a fit everytime I try to cut it. It's definitely some serious blade eating wood. I'll put one of the new blades in my saw later on tonight and give it a whirl. I'll let you know the outcome as soon as I can.

[tstagman]

Graham,

I cut on the oak for about 15 minutes with no problems at all. Then I decided to make some sharp turns and broke the first blade on the 4th 90 degree turn, about 3 or 4 teeth down from the top. I put another one in and slowed down my speed at the turns and made about a dozen of them without much problem other than the corners being a bit rounded instead of being nice and square and some mild scorching. (although I've never been able to cut real sharp turns with the larger blades).

They seem like they will work real well for cutting the long outside lines of a pattern done in thick wood, but I don't think after playing with it I would personally attempt many intricate inside cuts. I'm also fairly new to scrolling so hopefully one of the seasoned veterans on here will be able to help you a little more than I can.

[lucky788scroller]

I did have a couple of those thick wood blades a couple years ago and tried them. I dont really remember what I thought of them, but I know I didnt break them.In fact, I have never ever broke any flat blade while sawing on my Dewalts. A bunch of spirals, but never broke a flat blade in all the years of cutting (I imagine now I'll go break a dozen in a row!).Cutting through 2 inches of wood is a lot, even if its not really to hard of wood.The saws stroke isnt long enough to expell a sufficient amount of the sawdust to allow the teeth to keep on cutting.Your 22 inches of cut really doesnt seem like a bad distance considering the thickness of material your cutting.Apply a couple layers of clear packing tape on the top and also on the bottom of your wood. If you have any of the FD Polar blades in about a size 9 , thats what I would recommend using. My guess is the sawdust is packing in the cut because it cant escape,and with the gullets between the teeth filled with sawdust it is causing your blade to get hot and not be able to cut, so your pushing a little harder to get it cutting,causing the blade to snap. Also, do not even bother trying a reverse tooth blade, no matter what size, that wont solve your problem, only compound it.

[shinzam]

Thanks for all the replies,
I think Dale and Rick have hit the nail on the head with the sawdust packing the cut heat is being generated. I have been pulling back every so often to clear the cut but there is still a lot of sawdust. Mahogany, Douglas fir and tulip dust seams to stay in the cut longer and is finer than the harder woods. I am at the top end of the cutting limit of the Hegner I might have to reduce the thickness of the wood to accommodate the stroke length so it can remove more sawdust.
I have packaging tape on the top of the pattern but not underneath I will try that.
I will let you know how things progress.
Kevin what type of #12 are you using on what types of wood? I might need the thiner blade as suggested by Rick or get some #9 polars
Graham