Home |
Search |
Today's Posts |
|
Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
Hi all,
Iīve the following situation: 4 mm mild steel plate in which I made 6 mm holes with thread. In these holes I put bolts which I first dipped in epoxy to fix them in position and seal the thread waterproof. I screw the bolts in only for the thinkness of the plate, so a large part of the bolt and head is above the plate. After the epoxy is cured I cut the bolts with the angle grinder and grind what is left of it down until itīs surface is flush with the plate. The problem: cutting the bolt makes it really hot and the epoxy is only capable of withstanding temperatures up to 150 deg c. Above this it burns and does not seal anymore. What I tried to do is spray water onto the bolt while cutting. It seems to keep the proces a lot colder, but also somehow the cutting becomes slower with the water. Does anyone have a suggestion how to do the cutting and/or the cooling differently, better? greets, Joost Jager |
#2
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
wrote: (clip) After the epoxy is cured I cut the bolts with the angle grinder and grind what is left of it down until itīs surface is flush with the plate. (clip) ^^^^^^^^^^^^^^^^^^^^ If I've got this right, you drill and tap a hole, and then you plug the hole so you are back where you started. Why? Since you don't put any torque on the bolt when you screw it in, why not saw most of the way through it before you screw it in? After the epoxy sets, break it off or finish sawing, and then grind off smooth. |
#3
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
If I've got this right, you drill and tap a hole, and then you plug the hole
so you are back where you started. Why? Well, indeed, without the context this sounds pretty strange Iīll explain it. The metal plate is actually the deck of my boat, which was covered with teak wood. All these strips of teak were fastened to the deck with screws. After removing the teak (because it become really rusty underneath) I ended up with 800 holes, 5 mm. Which have to be closed. At first I wanted to weld them, no worries about corrosion or waterproofness. But on the inside there is sprayed-on foam which makes the welding unsafe. To remove the foam all the ceilings have to come out of the boat and to do that a lot of cupboards need to come out as well. Unfortunately the boatbuilder used nails on a lot of places, so it is really hard to remove interior parts without damage. Filling the holes with some epoxy based filler would have been easy, but after that it is impossible to sand blast, which is really necessary looking at the condition of the deck. So, therefore I figured out this method with drilling, tapping and glueing bolts. Since you don't put any torque on the bolt when you screw it in, why not saw most of the way through it before you screw it in? After the epoxy sets, break it off or finish sawing, and then grind off smooth. I thought about something like this too. Only I tried to do it with the angle grinder. Problem was that this made the bolt so hot that the zinc plating started looking strange and I had doubts whether the epoxy would still adhere to it. What you suggest, using a saw, would not be hot. But I donīt know if it is possible to do this quickly for all the 800 bolts. I also live on this boat. Well actually we are sailing around with it and have a working break now. But I donīt have many nice tools. Handsawing this quantity of bolts seems not very attractive to me. Maybe mounting the jigsaw upside down? How would you do it? |
#4
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
|
#5
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
wrote: (clip) Handsawing this quantity of bolts seems not very attractive to me. (clip) ^^^^^^^^^^^^^^^^^ I would use a portable, hand-held band saw like a Portaband or a Milwaukee. (A cheapo from Harbor Freight might work, but I don't know whether it would last through the whole job.) Hold each bolt in a vise, and cut it until it is easy to break. Another way would be to use a Saws-all to finish the cuts--the blade is flexible, so it can cut flush while the saw is held at an angle. If you can afford a boat, I would think you could easily handle the cost of a saw. If you don't feel like adding to your toolchest, you could rent a saw and easily cut the bolts in half a day. Is there a shop where your boat is docked? Maybe they would cut them for you for a fee. |
#6
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
|
#7
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
|
#8
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
|
#9
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
|
#11
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
|
#12
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
wrote in message ... Hi all, Iīve the following situation: 4 mm mild steel plate in which I made 6 mm holes with thread. In these holes I put bolts which I first dipped in epoxy to fix them in position and seal the thread waterproof. I screw the bolts in only for the thinkness of the plate, so a large part of the bolt and head is above the plate. After the epoxy is cured I cut the bolts with the angle grinder and grind what is left of it down until itīs surface is flush with the plate. The problem: cutting the bolt makes it really hot and the epoxy is only capable of withstanding temperatures up to 150 deg c. Above this it burns and does not seal anymore. What I tried to do is spray water onto the bolt while cutting. It seems to keep the proces a lot colder, but also somehow the cutting becomes slower with the water. Does anyone have a suggestion how to do the cutting and/or the cooling differently, better? greets, Joost Jager I would fill the holes with 3M 5200 sealant. It remains flexible, so sandblasting will have little effect on it. |
#13
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
The other degreasing method is hot alkaline wash. A tin can with water,
half a cup of laundry detergent, boiling merrily on the stove will take off most everything (including paint!) . Do a finish wash in plain boiling water, spread out on a clean surface. Joseph Gwinn wrote: In article Ru8aj.27658$UZ4.27060@edtnps89, Trevor Jones wrote: wrote: If I've got this right, you drill and tap a hole, and then you plug the hole so you are back where you started. Why? Well, indeed, without the context this sounds pretty strange Iīll explain it. The metal plate is actually the deck of my boat, which was covered with teak wood. All these strips of teak were fastened to the deck with screws. After removing the teak (because it become really rusty underneath) I ended up with 800 holes, 5 mm. Which have to be closed. At first I wanted to weld them, no worries about corrosion or waterproofness. But on the inside there is sprayed-on foam which makes the welding unsafe. To remove the foam all the ceilings have to come out of the boat and to do that a lot of cupboards need to come out as well. Unfortunately the boatbuilder used nails on a lot of places, so it is really hard to remove interior parts without damage. Filling the holes with some epoxy based filler would have been easy, but after that it is impossible to sand blast, which is really necessary looking at the condition of the deck. So, therefore I figured out this method with drilling, tapping and glueing bolts. Since you don't put any torque on the bolt when you screw it in, why not saw most of the way through it before you screw it in? After the epoxy sets, break it off or finish sawing, and then grind off smooth. I thought about something like this too. Only I tried to do it with the angle grinder. Problem was that this made the bolt so hot that the zinc plating started looking strange and I had doubts whether the epoxy would still adhere to it. What you suggest, using a saw, would not be hot. But I donīt know if it is possible to do this quickly for all the 800 bolts. I also live on this boat. Well actually we are sailing around with it and have a working break now. But I donīt have many nice tools. Handsawing this quantity of bolts seems not very attractive to me. Maybe mounting the jigsaw upside down? How would you do it? Buy a couple boxes of set screws from an indistrial supplier. Clean the hole with a brush on a cordless drill, install each set screw wet with epoxy, and fill the slot or hex head on the screw with the same on installation. You can use stainless set screws, if that works. To this I would add that the setscrews should be degreased before use by washing in solvent. The standard approach is three tubs of solvent and one basket. Tub 1 has the newest, cleanest solvent. Swish basket full of screws first in tub 3 (dirtyest solvent), shake excess off. Then swish in tub 2, and shake excess off. Then tub 1, shake excess, allow to dry. As tub 1 gets dirty, dispose of the solvent in tub 3, fill with new, clean solvent, and renumber the tubs: old 3 is new 1, old 1 is new 2, and old 2, is new 3. Repeat as needed. Solvents. I would use acetone. If you have access to a vapor degreaser, use it and skip the tub dance. Joe Gwinn |
#14
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
You don't have to hog it off in 2 seconds...blip it with the cutoff
wheel in time increments to reduce the heat. Grind flush the same way. Clamp a vice grip to the top of the bolt to help sink the heat. JR Dweller in the cellar wrote: Hi all, Iīve the following situation: 4 mm mild steel plate in which I made 6 mm holes with thread. In these holes I put bolts which I first dipped in epoxy to fix them in position and seal the thread waterproof. I screw the bolts in only for the thinkness of the plate, so a large part of the bolt and head is above the plate. After the epoxy is cured I cut the bolts with the angle grinder and grind what is left of it down until itīs surface is flush with the plate. The problem: cutting the bolt makes it really hot and the epoxy is only capable of withstanding temperatures up to 150 deg c. Above this it burns and does not seal anymore. What I tried to do is spray water onto the bolt while cutting. It seems to keep the proces a lot colder, but also somehow the cutting becomes slower with the water. Does anyone have a suggestion how to do the cutting and/or the cooling differently, better? greets, Joost Jager -- -------------------------------------------------------------- Home Page: http://www.seanet.com/~jasonrnorth If you're not the lead dog, the view never changes Doubt yourself, and the real world will eat you alive The world doesn't revolve around you, it revolves around me No skeletons in the closet; just decomposing corpses -------------------------------------------------------------- Dependence is Vulnerability: -------------------------------------------------------------- "Open the Pod Bay Doors please, Hal" "I'm sorry, Dave, I'm afraid I can't do that.." |
#15
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
If it was me, I'd install the screws with epoxy.
To remove the extra length of bolt above the deck, a cold chisel and hammer, or sawzall. To finish, a belt sander, but not dwelling in one place, keep moving. Or if all you have is a body grinder, get a wet or dry sanding disk,. Since you don't have much patience, that can be run wet. DJ On Dec 18, 11:07 pm, wrote: If I've got this right, you drill and tap a hole, and then you plug the hole so you are back where you started. Why? Well, indeed, without the context this sounds pretty strange Iīll explain it. The metal plate is actually the deck of my boat, which was covered with teak wood. All these strips of teak were fastened to the deck with screws. After removing the teak (because it become really rusty underneath) I ended up with 800 holes, 5 mm. Which have to be closed. At first I wanted to weld them, no worries about corrosion or waterproofness. But on the inside there is sprayed-on foam which makes the welding unsafe. To remove the foam all the ceilings have to come out of the boat and to do that a lot of cupboards need to come out as well. Unfortunately the boatbuilder used nails on a lot of places, so it is really hard to remove interior parts without damage. Filling the holes with some epoxy based filler would have been easy, but after that it is impossible to sand blast, which is really necessary looking at the condition of the deck. So, therefore I figured out this method with drilling, tapping and glueing bolts. Since you don't put any torque on the bolt when you screw it in, why not saw most of the way through it before you screw it in? After the epoxy sets, break it off or finish sawing, and then grind off smooth. I thought about something like this too. Only I tried to do it with the angle grinder. Problem was that this made the bolt so hot that the zinc plating started looking strange and I had doubts whether the epoxy would still adhere to it. What you suggest, using a saw, would not be hot. But I donīt know if it is possible to do this quickly for all the 800 bolts. I also live on this boat. Well actually we are sailing around with it and have a working break now. But I donīt have many nice tools. Handsawing this quantity of bolts seems not very attractive to me. Maybe mounting the jigsaw upside down? How would you do it? |
#16
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On Wed, 19 Dec 2007 10:52:50 -0500, with neither quill nor qualm,
"Chas Hurst" quickly quoth: wrote in message ... Hi all, Iīve the following situation: 4 mm mild steel plate in which I made 6 mm holes with thread. In these holes I put bolts which I first dipped in epoxy to fix them in position and seal the thread waterproof. I screw the bolts in only for the thinkness of the plate, so a large part of the bolt and head is above the plate. After the epoxy is cured I cut the bolts with the angle grinder and grind what is left of it down until itīs surface is flush with the plate. The problem: cutting the bolt makes it really hot and the epoxy is only capable of withstanding temperatures up to 150 deg c. Above this it burns and does not seal anymore. What I tried to do is spray water onto the bolt while cutting. It seems to keep the proces a lot colder, but also somehow the cutting becomes slower with the water. Does anyone have a suggestion how to do the cutting and/or the cooling differently, better? greets, Joost Jager I would fill the holes with 3M 5200 sealant. It remains flexible, so sandblasting will have little effect on it. If he's just going to fill and seal them anyway, why not just NOT drill and tap those holes in the first place? What a timesaver! gd&r -- Seen on a bumper sticker: ARM THE HOMELESS |
#17
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On Dec 19, 1:37 am, wrote:
Hi all, Iīve the following situation: 4 mm mild steel plate in which I made 6 mm holes with thread. In these holes I put bolts which I first dipped in epoxy to fix them in position and seal the thread waterproof. I screw the bolts in only for the thinkness of the plate, so a large part of the bolt and head is above the plate. After the epoxy is cured I cut the bolts with the angle grinder and grind what is left of it down until itīs surface is flush with the plate. The problem: cutting the bolt makes it really hot and the epoxy is only capable of withstanding temperatures up to 150 deg c. Above this it burns and does not seal anymore. What I tried to do is spray water onto the bolt while cutting. It seems to keep the proces a lot colder, but also somehow the cutting becomes slower with the water. Does anyone have a suggestion how to do the cutting and/or the cooling differently, better? greets, Joost Jager Spend 2 seconds on each, then go to the next one. |
#18
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
wrote in message ... Hi all, Iīve the following situation: 4 mm mild steel plate in which I made 6 mm holes with thread. In these holes I put bolts which I first dipped in epoxy to fix them in position and seal the thread waterproof. I screw the bolts in only for the thinkness of the plate, so a large part of the bolt and head is above the plate. After the epoxy is cured I cut the bolts with the angle grinder and grind what is left of it down until itīs surface is flush with the plate. The problem: cutting the bolt makes it really hot and the epoxy is only capable of withstanding temperatures up to 150 deg c. Above this it burns and does not seal anymore. What I tried to do is spray water onto the bolt while cutting. It seems to keep the proces a lot colder, but also somehow the cutting becomes slower with the water. Does anyone have a suggestion how to do the cutting and/or the cooling differently, better? greets, Joost Jager Get lengths of nylon threaded rod, goop-up the end, thread it in, cut it off with a hot-knife...next! |
#19
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
See if you can find stainless steel blind pop rivets. Coat the deck
with waterproof material and it is done. Since you are just trying to plug the holes, why not a plastic or rubber plug? Bob |
#20
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
RoyJ wrote:
The other degreasing method is hot alkaline wash. A tin can with water, half a cup of laundry detergent, boiling merrily on the stove will take off most everything (including paint!) . Do a finish wash in plain boiling water, spread out on a clean surface. TSP! |
#21
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On Dec 18, 10:37 pm, wrote:
\ Iīve the following situation: 4 mm mild steel plate in which I made 6 mm holes with thread. {and want to close the holes with steel plugs} Three options: Use rivets (i.e. put the overlength bit of threaded rod into place then hammer it, pneumatic riveter recommended, against a steel backing block). Sealant goo optional. Use glue (there are silicone adhesives that wouldn't have a problem with grinder cutoff temperatures). Use a shear plate. Basically, a hard steel 'nut' that snugs up on the allthread rod after you've plugged the hole, that takes a sidewise hammer blow and shears off the not-in-the-hole length of rod from the plug. |
#22
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
Idea 2; if not structural, why drill/tap for metal? Get a cheapy 4"
table saw from HF, cut wooden dowel of suitable dia. into lengths. Pound flush w/interference fit and a dab of 5200 sealant. JR Dweller in the cellar wrote: Hi all, Iīve the following situation: 4 mm mild steel plate in which I made 6 mm holes with thread. In these holes I put bolts which I first dipped in epoxy to fix them in position and seal the thread waterproof. I screw the bolts in only for the thinkness of the plate, so a large part of the bolt and head is above the plate. After the epoxy is cured I cut the bolts with the angle grinder and grind what is left of it down until itīs surface is flush with the plate. The problem: cutting the bolt makes it really hot and the epoxy is only capable of withstanding temperatures up to 150 deg c. Above this it burns and does not seal anymore. What I tried to do is spray water onto the bolt while cutting. It seems to keep the proces a lot colder, but also somehow the cutting becomes slower with the water. Does anyone have a suggestion how to do the cutting and/or the cooling differently, better? greets, Joost Jager -- -------------------------------------------------------------- Home Page: http://www.seanet.com/~jasonrnorth If you're not the lead dog, the view never changes Doubt yourself, and the real world will eat you alive The world doesn't revolve around you, it revolves around me No skeletons in the closet; just decomposing corpses -------------------------------------------------------------- Dependence is Vulnerability: -------------------------------------------------------------- "Open the Pod Bay Doors please, Hal" "I'm sorry, Dave, I'm afraid I can't do that.." |
#23
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On Wed, 19 Dec 2007 18:43:20 GMT, "Tom Gardner"
wrote: wrote in message ... Hi all, Iīve the following situation: 4 mm mild steel plate in which I made 6 mm holes with thread. In these holes I put bolts which I first dipped in epoxy to fix them in position and seal the thread waterproof. I screw the bolts in only for the thinkness of the plate, so a large part of the bolt and head is above the plate. After the epoxy is cured I cut the bolts with the angle grinder and grind what is left of it down until itīs surface is flush with the plate. The problem: cutting the bolt makes it really hot and the epoxy is only capable of withstanding temperatures up to 150 deg c. Above this it burns and does not seal anymore. What I tried to do is spray water onto the bolt while cutting. It seems to keep the proces a lot colder, but also somehow the cutting becomes slower with the water. Does anyone have a suggestion how to do the cutting and/or the cooling differently, better? greets, Joost Jager Get lengths of nylon threaded rod, goop-up the end, thread it in, cut it off with a hot-knife...next! The guy has a steel boat that had a wooden (teak) deck installed on it. These decks are normally about 1/2" thick and held down with about a million sheet metal screws. Water eventually leaks under the wood and corrodes the steel deck. The guy has removed the old rotten wood and now has to seal all those screw holes BUT the underside of the steel deck is sprayed with (probably) 2 inches of foam insulation that he doesn't want to dig out or weld near. As soon as he gets the holes filled he plans on sandblasting the deck to "white metal" and priming with (again probably) epoxy primer and then fill, fair and finish. How to fill the holes? Bruce-in-Bangkok (Note:remove underscores from address for reply) |
#24
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On Wed, 19 Dec 2007 15:00:35 -0500, Wes wrote:
RoyJ wrote: The other degreasing method is hot alkaline wash. A tin can with water, half a cup of laundry detergent, boiling merrily on the stove will take off most everything (including paint!) . Do a finish wash in plain boiling water, spread out on a clean surface. TSP! That would work, if you can still find the real stuff - AIUI the enviro-nuts don't like it anymore because of the phosphates in the waste water, and the substitutes aren't. Procedural note - Roy, if you want aggressive alkaline cleaning you want 'automatic dishwasher detergent' like Cascade, not 'laundry detergent' like 'Tide'. If you tried doing your laundry with something that alkaline, some items would go into the tub as cloth and come out as lace. -- Bruce -- |
#25
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
Bruce L. Bergman wrote:
That would work, if you can still find the real stuff - AIUI the enviro-nuts don't like it anymore because of the phosphates in the waste water, and the substitutes aren't. The local 'Do It Best' hardware store has it but you got to be careful not to get the TSP substitute. No wonder it was banned, it works! Wes |
#26
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
Bruce L. Bergman wrote:
That would work, if you can still find the real stuff - AIUI the enviro-nuts don't like it anymore because of the phosphates in the waste water, and the substitutes aren't. http://doitbest.com/Floor+Waxes+and+...sku-790574.dib |
#27
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On Fri, 21 Dec 2007 08:17:38 -0800, Bruce L. Bergman
wrote: On Wed, 19 Dec 2007 15:00:35 -0500, Wes wrote: RoyJ wrote: The other degreasing method is hot alkaline wash. A tin can with water, half a cup of laundry detergent, boiling merrily on the stove will take off most everything (including paint!) . Do a finish wash in plain boiling water, spread out on a clean surface. TSP! That would work, if you can still find the real stuff - AIUI the enviro-nuts don't like it anymore because of the phosphates in the waste water, and the substitutes aren't. Procedural note - Roy, if you want aggressive alkaline cleaning you want 'automatic dishwasher detergent' like Cascade, not 'laundry detergent' like 'Tide'. If you tried doing your laundry with something that alkaline, some items would go into the tub as cloth and come out as lace. -- Bruce -- Dead right, in context here. Note that dishwasher detergent doen't get active below 120F. I'm not making this up; I was told this by a P&G chemist. |
#28
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
Thank you all for the reactions. Iīm quite amazed by this enormous
response. Out of all the suggestions I chose to use the grubscrews. I found some zinc plated grub screws, which seems to be a little rare, so I donīt have to clean the oil off that is on the normal black oxide ones. What I do after removing the deck with brute force: 1. drill all holes with 5 mm 2. tap 6 mm thread into it with the tap on the battery drill in low gear using cutting oil 3. degrease the holes with carb cleaner 4. dip grubscrew in epoxy and screw in until top side of the screw is level with the deck 5. with a syringe I also fill the hex slot of the screw with epoxy 6. sandblast 7. paint 8. fill the hex slots again with epoxy filler, depending on how much of this was shot out by the blasting 9. paint again |
#29
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On Sat, 22 Dec 2007 00:27:29 -0600, Don Foreman
wrote: On Fri, 21 Dec 2007 08:17:38 -0800, Bruce L. Bergman wrote: On Wed, 19 Dec 2007 15:00:35 -0500, Wes wrote: RoyJ wrote: The other degreasing method is hot alkaline wash. A tin can with water, half a cup of laundry detergent, boiling merrily on the stove will take off most everything (including paint!) . Do a finish wash in plain boiling water, spread out on a clean surface. TSP! That would work, if you can still find the real stuff - AIUI the enviro-nuts don't like it anymore because of the phosphates in the waste water, and the substitutes aren't. Procedural note - Roy, if you want aggressive alkaline cleaning you want 'automatic dishwasher detergent' like Cascade, not 'laundry detergent' like 'Tide'. If you tried doing your laundry with something that alkaline, some items would go into the tub as cloth and come out as lace. Dead right, in context here. Note that dishwasher detergent doen't get active below 120F. I'm not making this up; I was told this by a P&G chemist. Which is why our "back" water heater is cranked all the way up, around 160F. You have to be careful at the kitchen sink, but both the clothes washing machine and the dishwasher are much happier. Should go get a couple of point-of-use sized tempering valves for the sinks, but I'm a firm believer in Darwin's Law. The steam is trying to tell you something... -- Bruce -- |
#30
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On Fri, 21 Dec 2007 22:28:05 -0800 (PST), joost
wrote: Thank you all for the reactions. Iīm quite amazed by this enormous response. Out of all the suggestions I chose to use the grubscrews. I found some zinc plated grub screws, which seems to be a little rare, so I donīt have to clean the oil off that is on the normal black oxide ones. What I do after removing the deck with brute force: 1. drill all holes with 5 mm 2. tap 6 mm thread into it with the tap on the battery drill in low gear using cutting oil 3. degrease the holes with carb cleaner 4. dip grubscrew in epoxy and screw in until top side of the screw is level with the deck 5. with a syringe I also fill the hex slot of the screw with epoxy 6. sandblast 7. paint 8. fill the hex slots again with epoxy filler, depending on how much of this was shot out by the blasting 9. paint again Okay, now that you have all the holes sealed what are you going to do with the bare deck? Anti-slip paint with silica sand, ground walnut shells or AlOx particles mixed in? Or make removable floorboard panels that only bolt down at the cross- slats and in the corners? That would be my first thought - they start looking bad every 10 years, pull them up and make new ones. -- Bruce -- |
#31
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
|
#32
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On Tue, 25 Dec 2007 00:06:18 -0500, JohnM wrote:
wrote: If I've got this right, you drill and tap a hole, and then you plug the hole so you are back where you started. Why? Well, indeed, without the context this sounds pretty strange Iīll explain it. The metal plate is actually the deck of my boat, which was covered with teak wood. All these strips of teak were fastened to the deck with screws. After removing the teak (because it become really rusty underneath) I ended up with 800 holes, 5 mm. Which have to be closed. At first I wanted to weld them, no worries about corrosion or waterproofness. But on the inside there is sprayed-on foam which makes the welding unsafe. To remove the foam all the ceilings have to come out of the boat and to do that a lot of cupboards need to come out as well. Unfortunately the boatbuilder used nails on a lot of places, so it is really hard to remove interior parts without damage. Filling the holes with some epoxy based filler would have been easy, but after that it is impossible to sand blast, which is really necessary looking at the condition of the deck. Have been there and done that. Get a bunch of socket head set screws. Drill and tap the screw holes and screw the set screws in after dipping the screws in epoxy or locktite. Make sure that they are flush. Let them set over night and sandblast the deck. Immediately prime, fill, fair and prime with high build primer. Finish sand and paint with 2 part paint. then apply antiskid of your choice. An alternate method would be to sandblast and immediately prime. then fill the holes with epoxy filler, fair and prime and finish. I suggest that the first methow\d will result in the longest lasting repair. Bruce-in-Bangkok (Note:remove underscores from address for reply) |
#33
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On 22 dec, 19:54, Bruce L. Bergman
wrote: On Fri, 21 Dec 2007 22:28:05 -0800 (PST), joost wrote: Thank you all for the reactions. Iīm quite amazed by this enormous response. Out of all the suggestions I chose to use the grubscrews. I found some zinc plated grub screws, which seems to be a little rare, so I donīt have to clean the oil off that is on the normal black oxide ones. What I do after removing the deck with brute force: 1. drill all holes with 5 mm 2. tap 6 mm thread into it with the tap on the battery drill in low gear using cutting oil 3. degrease the holes with carb cleaner 4. dip grubscrew in epoxy and screw in until top side of the screw is level with the deck 5. with a syringe I also fill the hex slot of the screw with epoxy 6. sandblast 7. paint 8. fill the hex slots again with epoxy filler, depending on how much of this was shot out by the blasting 9. paint again Okay, now that you have all the holes sealed what are you going to do with the bare deck? Anti-slip paint with silica sand, ground walnut shells or AlOx particles mixed in? Or make removable floorboard panels that only bolt down at the cross- slats and in the corners? That would be my first thought - they start looking bad every 10 years, pull them up and make new ones. -- Bruce -- Well, thatīs indeed a next problem. I feel most for anti slip paint, but Iīm still investigating the best way to do it. Many methods are not really good. I heard good stories though about some granite grain made by Sika. |
#34
Posted to rec.crafts.metalworking
|
|||
|
|||
Cutting bolt with minimal heat
On 25 dec, 13:02, Bruce in Bangkok wrote:
On Tue, 25 Dec 2007 00:06:18 -0500, JohnM wrote: wrote: If I've got this right, you drill and tap a hole, and then you plug the hole so you are back where you started. Why? Well, indeed, without the context this sounds pretty strange Iīll explain it. The metal plate is actually the deck of my boat, which was covered with teak wood. All these strips of teak were fastened to the deck with screws. After removing the teak (because it become really rusty underneath) I ended up with 800 holes, 5 mm. Which have to be closed. At first I wanted to weld them, no worries about corrosion or waterproofness. But on the inside there is sprayed-on foam which makes the welding unsafe. To remove the foam all the ceilings have to come out of the boat and to do that a lot of cupboards need to come out as well. Unfortunately the boatbuilder used nails on a lot of places, so it is really hard to remove interior parts without damage. Filling the holes with some epoxy based filler would have been easy, but after that it is impossible to sand blast, which is really necessary looking at the condition of the deck. Have been there and done that. Get a bunch of socket head set screws. Drill and tap the screw holes and screw the set screws in after dipping the screws in epoxy or locktite. Make sure that they are flush. Let them set over night and sandblast the deck. Immediately prime, fill, fair and prime with high build primer. Finish sand and paint with 2 part paint. then apply antiskid of your choice. An alternate method would be to sandblast and immediately prime. then fill the holes with epoxy filler, fair and prime and finish. I suggest that the first methow\d will result in the longest lasting repair. Bruce-in-Bangkok (Note:remove underscores from address for reply) Yes, this first method I will follow. It seems to be fast and good. |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
How to grow Ivy (with minimal sun) | Home Repair | |||
Cutting heat effected zone on aluminum | Metalworking | |||
Minimal bathroom... | Home Repair | |||
Removing a Frozen Bolt with Heat | Home Repair | |||
Why heat bolt and not around bolt? | Metalworking |