#6 Silicon Bronze Frearson Flat Head wood screws appear similar to the Phillips head but the Frearson has a more pointed 75° V shape. The Frearson tool recess is a perfect cross which minimizes cam out, unlike the Phillips head, which is designed to cam out.
Traditional boatbuilders love these Silicon Bronze wood screws because they have cut threads and the full-bodied diameter shank. Unlike rolled thread screws with their reduced shank--these screws have a shank diameter that is the same size as the outside of the threads. This completely fills the clearance hole normally drilled for the shank thus creating a waterproof seal.
The item was added to your wishlist.
The item was added to your shop cart.
Silicon Bronze is the traditional choice for marine construction. It is corrosion resistant, helps prevent rot around the screw holes when used under water, and is relatively strong. Although stronger than Solid Brass, Silicon Bronze screws are not as strong as Stainless Steel. They require a carefully sized pilot hole to avoid breakage. We recommend drilling twice (once for the root and once for the shank) as well as using fastener lubricant to avoid breakage.
MET / STD:
Does ANYONE make a standard hand screwdriver for a Frearson recess? Sometimes called a Red and Prince?
We only carry the Bitts, not a hand screwdriver in Frearson. You will see one for sale on ebay.
JD Tech Team
What is the diameter of the widest portion of the head of this screw?
Sorry, I used them all. My best guess is 1/4 in., but surely the supplier should be able to answer your question.
why not buy a few and find out
I don't actually know. I think that is the part that is #6
CHARLES DE ARMAS
Purchase a American Made micrometer, ask any American certified toolmaker to measure the diameter of the screw using the American Made micrometer and you will have your answer to assist the customer. Don't ever waste my time again pulling a stunt like this and wasting my time.
MR. BLAIR M. PHILLIPS
Go to the WL Fuller web site and they have all this information in a chart.google "standard screw sizes" and the WL Fuller site should pop up.
I am fastening 1/4 " marine plywood to the wooden frame of my pram using #8 Frearson silicon bronze screws. Should I use a countersink, or do I just predrill with a # 8 bit given the thinness of the plywood?
Bob Last Name
Definitely use a countersink.
CHARLES DE ARMAS
I Would Predrill The Holes So That THe Plywood Gets PulEd Down Tight To The Frames. I Would Predrill A Countersink So The Screw HEads Don't Pull The Top Veneer Up As It Squeezes Down. Plus You Will Be Able To Fill Over Them For A Better Finish.
If the plywood is soft and being glassed over you may not need to countersink it but if it is a hardwood plywood countersinking will be necessary.
P.S. You should pre-drill whether you countersink or not. May as well do it all in one step with a countersinking bore.
I had better luck with a countersink although some screws went in fine without.
First of all, I think the #8 is probably too large of a screw. A #6 might be better.Regarding the countersink, yes this is necessary. Otherwise the wood around the screw head will be compressed and leave a dimple. The wood could also splinter some. Given the thin plywood I wouldn't drill the countersink deep enough to actually recess the screw head. With just a bit of counter sink the recess can happen with the driving of the screw.
With Bronze and brass, I always counter sink just to be sure that the screw will not break. In hard woods, I usually drive the same type steel screw first and then remove and drive the softer metal screw. I also like to use a hand driver when feasible so I can feel how the screw is setting in the wood. Having broken many screws and going to the trouble of using a screw extractor and a plug to repair, I try to avoid the problem. Marine plywood can be hard due to the amount of glue that they use in it manufacturing.If you are driving many screws, the process above may cause a timing problem.I have found that the strength of bronze screws can vary, some may break when driven with a drill and some may not. I would experiment with some similar scrap pieces to see what happens and determine what process you want to use.Good luck.
Bob, I used a countersink to get a flush , smooth surface. If you do not use one you will get an irregular surface finish, of course do not go too deep with the countersink.
That really depends on how you plan on finishing. Even if the frame material is good enough to pull the screw in below the ply, the screw will force small raised edges of ply around the head. This is especially so if you are using the meranti based ply, much less so for okume. The raised ply is not a problem if you are planing to sand and cover with epoxy and glass, but not ideal if finished bright. Why not use a combination drill and countersink bit?
I would definitively pre-drill with a counter sink as the plywood will split and will not be as strong.
My inclination would be to do both - it would eliminate "crushing and splintering" around the screw head..... and reduce the risk of breaking off the screw heads while driving them. I have yet to snap one off. Nice screws me thinks...............
If you countersink, it should be done minimally. I think it gives a better finish and less stress on the wood itself. Just be very carefully not to go deep at all.Good luck.Bruce
Bob,great question. Plywood is a special case in that you don't want the screws to protrude, but neither do you want them to sink in below the outer ply. My advice is to try it without countersinking first and see if the screw head will countersink itself. The goal is for the head to be nicely flush with the surface. After a try or two countersink as necessary. My experience is that many plywoods will crush easily and don't need countersinking. Sometimes I countersink just a little to give it some help but let the screw draw itself down the rest of the way. Sorry if this is not a straightforward answer - as is often the case, you just have to establish the goal and adjust your process to get there.
Mine is not a marine use, can I drive with phillips bit?Thanks
A phillips will cam out and ruin the screw during final tightening. Get a frearson bit: one size fits all.
D. BRUCE STRATTON
If it is a Frearson screw a Phillips driver will strip the slots. You might be able to coax in one or two without damage, but if you are going to be driving lots you will want to get a set of Frearson screw drivers or bits.
Yes you can use a Phillips bit, but it does not fit into the slots as far as a Frearson so be carful as it may 'round out'.
Does not fit the phills head well and may stirp out the screw head
No, a Philips driver will not fit properly-I tried that myself. They do sell the Frearson drivers; it would be worthwhile getting the drivers. The screws themselves are excellent quality, but bronze is a little soft compared to steel.so you need to use the correct driver.
These type of screw are not very hard, so if you don't use a frearson bit you are going to wear the head of the screw. I ordered then the frearson bit in my order.Best regards.
Most likely. Look on wikipedia for frearson. Explains exactly the difference. If its not a high torque should be ok.
I recommend that you use a hand powered No. 1 Frearson drive bit since the screw is so small. The phillips bits tend to strip out these small heads since they don't go down into the shaft as deeply as the Frearson bit does. But if the wood is soft, and you use a hand powered small phillips screwdriver, it may work. You won't be able to supply much torque like this, and the angle of the driver to screw has to be perfect for this to work. I would actually recommend that you drive all #6 screws by hand. The impact drivers will strip them if anything is even slightly wrong with your method.
A phillips bit will tear up the screw head, Use a frearson bit
great for boats
Good for use in a wet environment
As always, JD delivers
Best price, excellent delivery service, what more can I add?