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Forum topic by HammerH posted 09-08-2019 08:25 PM 284 views 0 times favorited 13 replies Add to Favorites Watch
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HammerH

14 posts in 11 days


09-08-2019 08:25 PM

Hello,

I am brand new to the forum and am hoping for a bit of guidance on sanding wood.

First a little about me. I know nothing about woodworking!

I have been looking for a wood rack to hold my vinyl records and turntable for quite a while and decided I would try to build one myself. Please note, I have never built anything out of wood before. I bought a table saw, mitre saw and a brad nailer and went at it. I used birch plywood for the frame and 1” poplar for the casing in the front to hide the cut plywood.

Now to my questions. How should I sand it to prepare it for wood dye? Based on some videos I’ve seen they are all over the board with recommendations. Some suggest going 120-150-180, while others say 120-180-220. What should I use to sand it? I experimented with some scrap using an orbital sander which was fine on the plywood, but started to leave rings in the poplar. When I tried a hand sanding block it worked great on the poplar but left scratches in the plywood.

Any help would be greatly appreciated!

Thanks,
Hammer


13 replies so far

View Bill White's profile

Bill White

5225 posts in 4441 days


#1 posted 09-08-2019 09:25 PM

Light touch, let the sander do the work, work through the grits, use clean (or cleaned) sanding discs, move the sander slowly.

-- [email protected]

View bilyo's profile

bilyo

821 posts in 1583 days


#2 posted 09-09-2019 01:38 AM

The birch is probably slightly harder than the poplar. So, you might use the 120-150-180 on it and use the 120-180-220 on the poplar. You might even be able to start the poplar with 150. Veneer plywood is usually pretty smooth to start with. So, you might not need many strokes with the coarser grit.

The main concern is the plywood veneer. These days, the top veneer is frequently very thin. It is easy to sand through which tends to ruin a project for any finish but paint.

I strongly recommend you sand by hand with a flat block. Make some test panels to get a feel for how much to sand before applying your dye. You can check for scratches before proceeding with the next grit by wiping liberally with mineral spirits.

Always sand with the grain. Never cross grain.

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HammerH

14 posts in 11 days


#3 posted 09-09-2019 01:17 PM



The birch is probably slightly harder than the poplar. So, you might use the 120-150-180 on it and use the 120-180-220 on the poplar. You might even be able to start the poplar with 150. Veneer plywood is usually pretty smooth to start with. So, you might not need many strokes with the coarser grit.

The main concern is the plywood veneer. These days, the top veneer is frequently very thin. It is easy to sand through which tends to ruin a project for any finish but paint.

I strongly recommend you sand by hand with a flat block. Make some test panels to get a feel for how much to sand before applying your dye. You can check for scratches before proceeding with the next grit by wiping liberally with mineral spirits.

Always sand with the grain. Never cross grain.

- bilyo

Thanks for the tips! I watched a video last night on finishing poplar & it echoed your suggestion as well. The project is 56”x18”x40” so that’s a lot of sanding by hand, but I guess I will just have to adjust my timelines for completion and have Advil on hand for my shoulders.

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Robert

3516 posts in 1961 days


#4 posted 09-09-2019 01:38 PM

Usually 220 is about as high as you want to go. Stepping up from 120 or 180. If you need to get a joint flat or sand out a defect, then 80.

My advise is don’t be so quick to pick up an orbital sander. In fact, some cases its best to hand sand.

With your project, hand sanding will do it. If you’re getting scratches, its probably because you’re technique. Sand int a straight line, with the grain and you’ll be fine.

-- Everything is a prototype thats why its one of a kind!!

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HammerH

14 posts in 11 days


#5 posted 09-09-2019 02:33 PM



Usually 220 is about as high as you want to go. Stepping up from 120 or 180. If you need to get a joint flat or sand out a defect, then 80.

My advise is don t be so quick to pick up an orbital sander. In fact, some cases its best to hand sand.

With your project, hand sanding will do it. If you re getting scratches, its probably because you re technique. Sand int a straight line, with the grain and you ll be fine.

- Robert

Thanks!

View PaulDoug's profile (online now)

PaulDoug

2124 posts in 2184 days


#6 posted 09-09-2019 02:57 PM

I don’t see anyone recommending a pre-stain conditionar for the plywood. I know Minwax makes one. It is applied after sanding, before staining. Helps prevent the blotches that happen, especially with plywood. What is the consciences on that?

I have great results on plywood using gel stains, like General or Old Masters.

Sorry this is beyond the sanding question, but I would hate to see it sanded and then end up with blotches.

-- “We all die. The goal isn't to live forever; the goal is to create something that will.” - Chuck Palahniuk

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HammerH

14 posts in 11 days


#7 posted 09-10-2019 09:48 PM



I don t see anyone recommending a pre-stain conditionar for the plywood. I know Minwax makes one. It is applied after sanding, before staining. Helps prevent the blotches that happen, especially with plywood. What is the consciences on that?

I have great results on plywood using gel stains, like General or Old Masters.

Sorry this is beyond the sanding question, but I would hate to see it sanded and then end up with blotches.

- PaulDoug

No, this is totally on point. I had planned to use a Varathane pre-stain conditioner on all the wood for the project. I plan on using a poly to finish and have a couple questions.

Do I need multiple coats of the poly or is one coat sufficient?

How long after the poly dries is it safe to start loading the rack with stereo equipment and records?

Thanks!

View bilyo's profile

bilyo

821 posts in 1583 days


#8 posted 09-11-2019 12:45 AM

No, this is totally on point. I had planned to use a Varathane pre-stain conditioner on all the wood for the project. I plan on using a poly to finish and have a couple questions.

Do I need multiple coats of the poly or is one coat sufficient?

How long after the poly dries is it safe to start loading the rack with stereo equipment and records?

Thanks!

- HammerH


It depends. Follow mfg recommendations. If you are using a product straight out of the can, I think, most recommend 3 coats and suggest a light sanding with 220 grit between coats. If you are thinning the product or using a wipping product (pre-thinned), you will need more coats. This goes for either oil based or water based.

Most will dry to the touch in a short time. Again, follow the mfg recommendation for cure time before full service. I would wait several days.

View ibewjon's profile

ibewjon

911 posts in 3274 days


#9 posted 09-11-2019 01:09 AM

Don’t rush the dry time. Dry to the touch and fully cured are different. Even if the surface feels dry, if it is not fully cured, whatever you put on it will sink into the surface and stick. I of course learned the hard way many years ago. Water based finish might be different.. Curing depends on your conditions. Just don’t rush it.

View HammerH's profile

HammerH

14 posts in 11 days


#10 posted 09-11-2019 02:40 AM


No, this is totally on point. I had planned to use a Varathane pre-stain conditioner on all the wood for the project. I plan on using a poly to finish and have a couple questions.

Do I need multiple coats of the poly or is one coat sufficient?

How long after the poly dries is it safe to start loading the rack with stereo equipment and records?

Thanks!

- HammerH

It depends. Follow mfg recommendations. If you are using a product straight out of the can, I think, most recommend 3 coats and suggest a light sanding with 220 grit between coats. If you are thinning the product or using a wipping product (pre-thinned), you will need more coats. This goes for either oil based or water based.

Most will dry to the touch in a short time. Again, follow the mfg recommendation for cure time before full service. I would wait several days.

- bilyo

Got it, thanks!

View HammerH's profile

HammerH

14 posts in 11 days


#11 posted 09-11-2019 02:45 AM



Don t rush the dry time. Dry to the touch and fully cured are different. Even if the surface feels dry, if it is not fully cured, whatever you put on it will sink into the surface and stick. I of course learned the hard way many years ago. Water based finish might be different.. Curing depends on your conditions. Just don t rush it.

- ibewjon

Thanks, patience is not one of my virtues and I tend to rush projects just to get them done, which is why I have avoided woodworking for so long. Would you think 7-days at 77*F & 49% RH would be enough curing time?

View Madmark2's profile

Madmark2

485 posts in 1069 days


#12 posted 09-11-2019 03:41 AM

If you ask 1000 woodworkers you’ll get 1,001 answers to how to finish. More coats = more durable = more sanding, steel wool and buffing. Or the cover for all sins – paint.

View wildwoodbybrianjohns's profile

wildwoodbybrianjohns

184 posts in 28 days


#13 posted 09-11-2019 06:12 AM

I didnt see this mentioned above, so, if you are getting ring patterns when sanding with the orbital, then you are pressing down too hard, let the weight of the sander alone do the work.

-- Wildwood by Brian Johns: It is wiser to find out, than to suppose (S. Clemens)

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